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A cohort study of epilepsy among 665,000 insured dogs: Incidence, mortality and survival after diagnosis

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... 6,7 To date, most studies have focused on the subset of cases that are classified as epileptic. 8,9 Seizures are either epileptic or reactive according to the classification of the IVETF. Epileptic seizures are manifestations of excessive synchronous neuronal activity in the brain that is usually self-limiting and that are promoted by a predisposition of the brain for ictogenesis. ...
... 1,3 Analysis of a large pet insurance database reported an epilepsy incidence of 18 per 10,000 dog years at risk (DYAR) in Sweden for either idiopathic epilepsy or epileptic convulsions. 8 A study using primary-care veterinary clinical data reported a prevalence of 0.62% for epilepsy in dogs in the UK. 9 A cross sectional study compared period prevalence of epileptic seizures in a 2.5-year observation period between first opinion practices (0.43%) and a referral clinic in southern Germany (1.78%). 12 Among the referral subset of dogs seen at a veterinary teaching hospital in Germany, 2.6% had a history of seizures reported. ...
... Increased risk for epileptic seizures in male dogs is recognized across all dogs types8,9,[50][51][52][53] as well as within specific breeds.10 Our analysis of UK primary-care veterinary data that included both epileptic and reactive seizures also revealed a higher risk for male dogs. ...
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Background: Primary-care veterinary clinical records can offer data to determine generalizable epidemiological data on seizures occurrence in the dog population. Objectives: To identify and examine epidemiologic characteristics of seizure occurrence in dogs under primary veterinary care in the UK participating in the VetCompass™ Programme. Animals: 455,553 dogs in VetCompass™'. Methods: A cross-sectional analysis estimated the 1-year period prevalence and risk factors for dogs with seizures during 2013. Results: The overall 1-year period prevalence for dogs having at least one seizure during 2013 was 0.82% (95% CI 0.79-0.84). Multivariable modelling identified breeds with elevated odd ratios [OR] compared with the Labrador Retriever (e.g. Pug OR: 3.41 95% CI 2.71-4.28, P < 0.001). Males had higher risk for seizures (Male/Entire OR: 1.47 95% CI 1.30-1.66; Male/Neutered OR: 1.34 95% CI 1.19-1.51) compared to entire females. Age (3.00 - ≤ 6.00 OR: 2.13 95% CI 1.90-2.39, P < 0.001, compared to animals aged 0.50-≤ 3.00 years), and bodyweight (≥ 40.00kg, OR: 1.24 95% CI 1.08-1.41, P = 0.002, compared to animals weighing < 10.0 kg) were identified as risk factors for seizures. Conclusion and clinical importance: Seizures are a relatively common clinical finding in dogs. The results for breed, age, sex and bodyweight as risk factors can assist veterinarians in refining differential diagnosis lists for dogs reported with behaviors that may have been seizures. In addition, the prevalence values reported here can support pharmacovigilance with baseline data from the overall population.
... Keywords: idiopathic epilepsy, seizure, phenotype, dog, incidence, breed INTRODUCTION Epilepsy is one of the most common neurological chronic diseases in humans and dogs (1)(2)(3). The prevalence is generally reported to be 0.6-0.75% in the overall canine population and up to 18.3% in certain breeds (1,(4)(5)(6). Epilepsy is described as a disorder of the brain, characterized by a persistent predisposition to produce epileptic seizures (7,8). The definition of seizure etiology has been standardized for veterinary medicine by the IVETF consensus: a distinction is made between structural epilepsy (StE) and idiopathic epilepsy (IE), which in turn both differ from reactive seizures (RS) (7). ...
... In our German GSMD with IE, the median age at death was 4 years with a median survival time from first seizure to time of death of 1.5 years. This outcome was also shown by Heske et al. (5) in a cohort study of epilepsy, in which the median survival time after diagnosis was reported to be 1.5 years. In another study on "Premature Death, Risk Factors, and Life Patterns in Dogs with Epilepsy", the median age of several breeds of dogs at death was found to be 7 years and the survival time was found to be 2.3 years (29). ...
... Statistically, no significant influence on survival time by age at first seizure, sex, number of antiseizure drugs, or administration of phenobarbital or imepitoin was found in the study discussed here. In contrast, Heske et al. (5) and Berendt et al. (29) found that females lived longer than males after a diagnosis of epilepsy, although this refers to a mixed dog breed population. Also, in the mixed population of dogs with IE, a higher age at diagnosis correlated with a shorter survival time (5). ...
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Genetic predisposition of idiopathic epilepsy (IE) has been demonstrated in individual breeds. According to the responsible breeding association in Germany, the average incidence of registered Great Swiss Mountain Dogs (GSMDs) with seizures between the years 1999 and 2019 is 2.56%, a genetic predisposition in this breed is suspected. To describe the seizure phenotype and to examine seizure causes, a retrospective, questionnaire-based study was performed. In cooperation with the Swiss Mountain Dog Association of Germany e.V. (SSV e.V.), 114 questionnaires filled in by owners of GSMD displaying seizures and filled in by their respective veterinarians between the years 2005–2021 were evaluated. Seizure characteristics, clinical and further examinations, treatment, treatment responses, and pedigree information were collected. In this study, 94 (83.06%) dogs had IE (suspected genetic epilepsy) confirmed with confidence level TIER 1, 2, or 3. The remaining 20 dogs showed the signs of structural epilepsy, reactive seizures, or epilepsy of unknown cause and were therefore excluded from further analysis. The average age at seizure onset was 28.83 months. Male GSMDs were significantly more often affected by IE than females. The most common seizure type was focal evolving into generalized seizures (64.5%). Seizures often began with vomiting, retching, or salivation. Cluster seizures (CS) (48.9%) and status epilepticus (SE) (37.2%) were observed in a large proportion of dogs. During the observation time, a total of 49 animals (52.13%) died. Out of those, 19 dogs (20.21%) were euthanized in SE or during CS and 14 dogs (14.9%) died spontaneously during CS or SE. The median age at death was 4 years, and the median survival time for the time, when the dog was suffering from seizures, was found to be 18 months. Both occurrence of CS (p = 0.0076) and occurrence of SE (p = 0.0859) had an impact on survival time. In GSMD, idiopathic epilepsy presents with a severe phenotype with frequently occurring CS and SE. This study could serve as basis for further genetic evaluations as well as to provide individual treatment recommendations.
... The prevalence of epilepsy in the general dog population is estimated to be 0.6-0.75% (1)(2)(3)(4)(5)(6). Breed-specific characteristics (phenotype or clinical manifestation) of idiopathic epilepsy (IE) have been reported for a variety of breeds, but most are based on single studies from specific countries with notable exceptions such as the Belgian Shepherd, Golden Retriever, and Finnish Spitz (6). ...
... Breed-specific characteristics (phenotype or clinical manifestation) of idiopathic epilepsy (IE) have been reported for a variety of breeds, but most are based on single studies from specific countries with notable exceptions such as the Belgian Shepherd, Golden Retriever, and Finnish Spitz (6). Although it is well-established within the veterinary neurology community that Border Collie (BC) dogs show a high prevalence of IE (1)(2)(3)(4)(5)(6), there is only one report that focuses on IE in this breed, based on a cohort of 49 BC dogs from Germany (7). Another study investigated IE in Labradors and Border Collies from the UK and the impact of neutering (8). ...
... The prevalence of IE in the BC breed has been shown to be high in many studies (1)(2)(3)(4)(5)(6). Although a strong indication for a genetic background to the occurrence of IE in BC dogs is reported based on pedigree analysis (7), the causal genetic mutation(s) have not been identified yet. ...
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The prevalence of idiopathic epilepsy (IE) within the Border Collie (BC) dog breed is high. The aim of this retrospective study was to describe the phenotype of BCs with IE and assess correlations between phenotypic variables and owner-provided quality-of-life (QoL) scores. Data of BCs diagnosed with IE during the period of five consecutive years were retrospectively analyzed. All the dogs were presented at least once to a veterinary neurology specialist at one of three veterinary referral hospitals and most were under the continued medical care of that specialist. Owners were requested to complete a standardized online questionnaire including quality-of-life (QoL) scoring questions. Data of a total of 116 BC dogs were included for analysis. The median age at onset of the first epileptic seizure (ES) was 33.5 months (6–188). A total of 34/86 (40%) of medically treated dogs received 1 antiseizure medication (ASM) and 52/86 (60%) received ≥2 ASMs. Phenobarbital was the most commonly employed ASM, used in 70/86 of treated dogs (81%). Four or more side effects were observed in 20/86 (23%) of treated dogs. Age at onset of first ES was significantly lower for dogs having experienced cluster seizures (CSs), status epilepticus (SE), or both (median 27 months) vs. dogs that had not experienced CS or SE (median 43 months). The QoL of BC with IE was scored with a median score of 7 out of 10. Owners scored their dog's QoL to have declined by a median of 30% during the course of life with IE with 39% (37/95) of owners scoring their dog's QoL to have declined by ≥50%. This study confirms the association of age at onset of first ES with the severity of epilepsy (e.g., presence of CS and/or SE) and further characterizes the phenotype of IE in BC dogs. QoL of BC can be heavily impacted by IE.
... Two recent studies identified the Boxer as the breed with the highest prevalence of seizures (16,17). In addition, a predisposition for Boxer dogs to develop intracranial tumors, both intra-axial and extra-axial, is reported (15,(17)(18)(19)(20)(21)(22)(23)(24), as well as a predisposition for hereditary epilepsy (25). ...
... Two studies conducted on the prevalence of epileptic seizures in the general canine population in primary veterinary care reported a percentage of 0.75-0.82% and identified the Boxer as the breed with the highest seizure prevalence (1.8-2.3%, respectively) (16,17). ...
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The prevalence of idiopathic epilepsy and structural epilepsy in Boxer dogs is unknown. The aim of this retrospective study was to evaluate the prevalence of structural and idiopathic epilepsy in the Boxer population. A total of 74 Boxer dogs were included in the study from the database of one referral hospital and the following were recorded: signalment, history, clinical findings and results of advanced diagnostic imaging. Five dogs (6.8%) were diagnosed with idiopathic epilepsy, of which one was in the <6 months age group, three were in the 6–72 months age group and one was in the >72 months age group. Sixty-nine dogs (93.2%) were diagnosed with structural epilepsy. Sixty-six had a suspected intracranial neoplasia: Eight were in the 6–72 months age group and represent 66.7% of the dogs in that age group. The other fifty-eight were in the >72 months age group and represent 96.7% of the dogs in that age group. In our Boxer population, 81.8% of the patients had a suspected intra-axial tumor and 22.7% of dogs with an intracranial pathology nevertheless had a normal neurological examination. In conclusion, in the majority of boxer patients the cause of epilepsy is a suspected intracranial neoplasia regardless of the age at presentation. Considering the finding in this study of a low prevalence of presumed idiopathic epilepsy in the Boxer breed, it is recommended that patients who satisfy Tier I confidence level of the “International Veterinary Epilepsy Task Force” (IVETF) also undergo an MRI study of the brain.
... These results confirm that although RSD are less frequently diagnosed in cats than in dogs, 7,8,37 RSD are a relatively common clinical presentation for cats evaluated by veterinary practitioners, which is consistent with previous reports. 38 Despite substantial progress in recent decades on the classification of neurological diseases in companion animals 5 along with efforts to formally define internationally-accepted diagnostic lexicons and definitions, 19 reluctance remains for primary care practitioners to evaluate and identify their neurological clinical caseloads. ...
... 55 This insurance bias must be considered carefully when generalizing the results of studies that are based entirely on data from insured animals. 37 We did not report the proportion of animals referred for specialist management or that underwent advanced imaging, but it would have been useful to know these because a normal brain MRI and cerebrospinal fluid (CSF) analysis would increase confidence in a diagnosis of idiopathic epilepsy and insured animals are more likely to undergo this level of diagnostic evaluation. ...
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Background: Little epidemiological evaluation of recurrent seizure disorders in cats currently exists in veterinary literature. Objectives: To report the prevalence and risk factors for recurrent seizure disorders (RSD) and epilepsy in cats presented to primary care veterinary practices in the United Kingdom (UK). Animals: A total of 285 547 cats under veterinary care during 2013 presenting to 282 primary care clinics in the UK. Methods: Cohort study using multivariable logistic regression modeling for risk factor analysis. Results: There were 458 confirmed RSD cases, giving a 1-year period prevalence of 0.16% (95% confidence interval [CI], 0.15-0.18). A subset of 114 (24.89%) cases was recorded as having epilepsy, giving a 1-year period prevalence of 0.04% (95% CI, 0.03-0.5). Increasing age was significantly associated with increasing odds of RSD. Breed, sex, neuter status, and body weight were not associated with RSD. Epilepsy was most frequently diagnosed in adult to middle-aged cats. Cats aged 3.0 to <6.0 years had 3.32 times higher odds of epilepsy diagnosis compared to cats <3.0 years of age. Insured cats were more likely to be diagnosed with epilepsy compared to noninsured cats. Conclusions and clinical importance: Although less common than in dogs, RSD and epilepsy still comprise an important disorder group in the UK cat population. Aging is a significant risk factor for these disorders in cats.
... Canine epilepsy is one of the most common neurological conditions encountered in small animal and referral practice, with an estimated prevalence of 0.62 per cent to 0.82 per cent in a first-opinion setting. [1][2][3] Epilepsy is a complex brain disease characterised by an enduring predisposition to generate epileptic seizures. 4 In a clinical context, this definition is generally applied as a history of at least two unprovoked epileptic seizures more than 24 hours apart. ...
... [11][12][13] Larger-scale studies utilising first opinion populations often lack tier II investigations such as MRI, leading to a reduced confidence in the underlying cause of seizures. [1][2][3] Consequently, the true prevalence of IE and SE in dogs experiencing seizures in general practice remains poorly characterised. For example, estimates of IE in the general canine population range from 40 per cent to 60 per cent of all canine patients presenting with seizures and data vary markedly by study population selected and patient signalment; with breed, sex and neuter status all affecting estimates. ...
Article
Due to variation in study designs the prevalence of idiopathic epilepsy (IE) and structural epilepsy (SE) in dogs is largely unknown. The objective was to provide estimates of the prevalence of IE and SE in a large population of dogs undergoing MRI for epileptic seizures. A retrospective study on 900 dogs undergoing MRI for seizures was performed. MRI scans, summary clinical history and neurological examination from the VetCT database were reviewed and a diagnosis assigned by board-certified radiologists. Structural lesions were identified as a cause of seizures in 45.1 per cent (n=406) of cases. No structural lesions were identified in 54.9 per cent (n=494) of cases with presumed IE diagnosed in 53.8 per cent (n=484) of dogs. Dogs between six months and six years were more often associated with IE (P<0.001), small breeds were overrepresented with suspected inflammatory brain disease (P=0.001) and large entire dogs more often diagnosed with extra-axial neoplasms (P=0.001). Over 31.0 per cent of dogs with suspected IE were six years or older. This study is the largest of its kind in dogs and provides accurate estimates of underlying causes of epilepsy. MRI findings should be considered in the context of a detailed clinical history and neurological examination.
... Idiopathic epilepsy (IE) is a common neurological disorder, with an estimated prevalence of 0.5% to 0.82% in the general canine population, and up to 33% in certain families of genetically predisposed breeds. [1][2][3][4][5][6][7] Drug resistance occurs in up to 30% of the dogs with IE leading to a grave prognosis and eventually euthanasia because of limited nonpharmacological treatment options. 8 Repetitive transcranial magnetic stimulation (rTMS) has received attention the recent years as a treatment method that can have neuromodulatory effects on the brain that last longer than the duration of the neurostimulation. ...
... The results are summarized inTable 2. Based on the MSF ratio, the median rTMS effect lasted for 4 months (range, 2-6). Median follow-up of the dogs from inclusion in the active treatment group until termination of the study was 5 months (range,[3][4][5][6]. No adverse effects related to the treatment were reported.4 ...
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Background: Although repetitive transcranial magnetic stimulation (rTMS) has been assessed in epileptic humans, clinical trials in epileptic dogs can provide additional insight. Objectives: Evaluate the potential antiepileptic effect of rTMS in dogs.Animals: Twelve client-owned dogs with drug-resistant idiopathic epilepsy (IE). Methods: Single-blinded randomized sham-controlled clinical trial (dogs allocated to active or sham rTMS) (I) and open-labelled uncontrolled clinical trial (dogs received active rTMS after sham rTMS) (II). Monthly seizure frequency (MSF), monthly seizure day frequency (MSDF), and number of cluster seizures (CS) were evaluated for a3-month pre-TMS and post-rTMS period and safety was assessed. The lasting effectperiod of rTMS was assessed in each dog treated by active stimulation using theMSF ratio (proportion of post-TMS to pre-rTMS MSF) and treatment was considered effective if the ratio was <1. Results: No adverse effects were reported. In trial I, MSF and MSDF decreased significantly (P = .04) in the active group (n = 7). In the sham group (n = 5), no significant changes were found (P = .84 and .29, respectively). Cluster seizures did not change significantly in either group. No significant differences were detected between the groups. In trial II, previously sham-treated dogs (n = 5) received active rTMS and significant decreases in MSF and MSDF were noted (P = .03 and .008, respectively). The overall effect of rTMS lasted for 4 months; thereafter, the MSF ratio was >1. Conclusions and Clinical Importance: Repetitive transcranial magnetic stimulation may be a safe adjunctive treatment option for dogs with drug-resistant IE, but large-scale studies are needed to establish firm conclusions
... Idiopathic epilepsy (IE) is estimated to affect between 0.60-0.75% of the general canine population [1,2]. Unlike structural epilepsy or reactive seizures, where a cause can be found with rigorous clinical investigations, the diagnosis of IE remains one of exclusion [3]. ...
... One database was searched manually and the other using VetCompass. 1 Dogs with IE were required to have at least a Tier I confidence level diagnosis [3] for inclusion. Controls were identified from dogs found to have an unremarkable brain on MRI (for reasons other than seizures) and following thorough examination of their clinical history. ...
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Background Canine idiopathic epilepsy (IE) is the most common chronic neurological brain disease in dogs, yet it can only be diagnosed by exclusion of all other potential causes. In people, epilepsy has been associated with a reduction in brain volume. The objective was to estimate the volume of the forebrain (FB), subarachnoid space (SAS) and lateral ventricles (LV) in dogs with IE compared to controls using Cavalieri’s principle. MRI scans of case and control dogs were identified from two neurology referral hospital databases. Eight breeds with increased odds of having IE were included: Golden Retriever, Labrador Retriever, Cocker Spaniel, Border terrier, German Shepherd dog, Parson Jack Russell terrier, Boxer, and Border Collie. Five dogs of each breed with IE and up to five controls were systematically and uniformly randomly sampled (SURS). The volume of the FB, SAS and LV were estimated from MRI scans by one blinded observer using Cavalieri’s principle. Results One hundred-two dogs were identified; 56 were diagnosed with IE and 46 were controls. There was no statistically significant difference in FB, SAS and LV volume between dogs with IE and controls. Dogs with a history of status epilepticus had significantly larger FB than those without ( p = 0.05). There was a border-line trend for LV volume to increase with increasing length of seizure history in the IE group ( p = 0.055). Conclusion The volumes of the FB, SAS and LV are not different between dogs with IE and controls, so IE remains a diagnosis of exclusion with no specific neuroanatomical biomarkers identified. This is the first time FB and SAS volume has been compared in dogs with IE. Unfortunately, we have shown that the results reporting significantly larger FBs in dogs with status epilepticus and LV volume increase with length of seizure history were likely confounded by breed and should be interpreted cautiously. Whilst these associations are interesting and clinically relevant, further investigation with breed-specific or larger, breed-diverse populations are required to permit strong conclusions. The Cavalieri principle provided an effective estimation of FB, SAS and LV volumes on MRI, but may be too time-intensive for use in clinical practice.
... The data presented in this study highlight significant changes shown in both the fecal microbiome and lipidome as a result of consumption of the MCT-KD. Elucidating the global canine gut response to INTRODUCTION Epilepsy is a common chronic neurological disorder in dogs with an estimated prevalence of 0.6-0.75% in first opinion practice (1,2). Epilepsy in dogs has been associated with increased risk of premature and unexpected death, injuries, neurobehavioral, and cognitive dysfunction and reduced quality of life (3)(4)(5). ...
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Consumption of diets containing medium chain triglycerides have been shown to confer neuroprotective and behavior modulating effects. We aimed to identify metabolic and microbiome perturbations in feces that are associated with consumption of a medium chain triglyceride ketogenic diet (MCT-KD) in dogs with idiopathic epilepsy. We used 16S rRNA gene sequencing to generate microbiome profiles and ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) to generate lipidomic profiles of canine feces. We made comparisons between the MCT-KD, standardized placebo diet and baseline pre-trial diet phases. Consumption of the MCT-KD resulted in a significant increase in the species richness (α-diversity) of bacterial communities found in the feces when compared to the baseline diet. However, phylogenetical diversity between samples (beta-diversity) was not affected by diet. An unnamed Bacteroidaceae species within genus 5-7N15 was identified by LEfSe as a potential biomarker associated with consumption of the MCT-KD, showing an increased abundance ( p = 0.005, q = 0.230) during consumption of MCT-KD. In addition, unclassified members of families Erysipelotrichaceae ( p = 0.013, q = 0.335) and Fusobacteriaceae ( p = 0.022, q = 0.358) were significantly increased during MCT-KD consumption compared to baseline. Blautia sp. and Megamonas sp. instead were decreased during consumption of either placebo or MCT-KD ( p = 0.045, q = 0.449, and p = 0.039, q = 0.449, respectively). Bacteroidaceae , including genus 5-7N15 , have previously been associated with non-aggressive behavior in dogs. In addition, 5-7N15 is correlated in humans with Akkermansia , a genus known to be involved in the neuroprotective effect of ketogenic diets in mice models of seizures. Five metabolite features, tentatively identified as long chain triglycerides, were significantly higher after consumption of the placebo diet, but no unique features were identified after consumption of the MCT-KD. The data presented in this study highlight significant changes shown in both the fecal microbiome and lipidome as a result of consumption of the MCT-KD. Elucidating the global canine gut response to MCT consumption will improve our understanding of the potential mechanisms which confer anti-seizure and behavior modulating effects. Further studies should aim to characterize the gut microbiome of both dogs with epilepsy and healthy controls.
... 20 Sogar innerhalb einer Rasse können sich diese Merkmale in geographisch getrennten Subpopulationen unterscheiden. 20 Während in der gesamten Hundepopulation die Prävalenz zwischen 0,6 und 0,75% 16 Definitionen und diagnostische Kriterien für idiopathische Epilepsie wurden den aktuellen Guidelines der Veterinary Epilepsy task force entnommen. 1,9 Basiert die Diagnose der IE auf einer Anamnese von zwei oder mehr nicht provozierten epileptischen Anfällen, die mindestens 24 Stunden auseinander liegen, einem Alter bei erstmaligem Auftritt des epileptischen Anfalls zwischen sechs Monaten und sechs Jahren, sowie auf normalen Befunden, der in der anfallsfreien Phase durchgeführten Allgemeinuntersuchung, neurologischen Untersuchung sowie Blut und Urinuntersuchung, so entspricht dies der Tier I Kategorie (Zuverlässigkeitsgrad 1). ...
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Introduction: Background: Little is known about idiopathic Epilepsy in Greater Swiss Mountain Dogs. Until now this breed is not listed as a predisposed breed for idiopathic epilepsy. The aim of this study was to estimate the prevalence of idiopathic epilepsy in Greater Swiss Mountain Dogs in Switzerland and to describe the clinical characteristics of epilepsy in this breed including seizures semiology and response to treatment. Material and Methods: Records of the Swiss Kennel Club for Greater Swiss Mountain Dogs were searched for reported cases of epileptic seizures between 1999-2019. The total number of reported cases and the signalment was reviewed. Furthermore, all owners of Greater Swiss Mountain Dogs registered to the breeding club were invited to complete an online questionnaire. Results: In total 600 Greater Swiss Mountain Dog's live in Switzerland: 70-90 puppies are born each year. Between 1999 and 2019 34 dogs (2%) were announced with seizures. Of the 400 owners invited to answer the questionnaire 128 completed the questionnaire. 20 of these 128 dogs were suffering from idiopathic epilepsy. The prevalence for idiopathic epilepsy based on the questionnaire was therefore 15,6%. All affected dogs showed generalized tonic-clonic seizures. Cluster seizures and status epilepticus occurred in 5 (41,6%) and 6 (50%) of the dogs. Long term seizure control was only achieved in 10% of the dogs. Five dogs (25%) died or were euthanized because of insufficient seizure control. Only one dog (5%) showed clinical remission. Conclusion: Prevalence of idiopathic epilepsy is higher in Greater Swiss Mountain Dogs in Switzerland compared to the general dog population. Seizure control seems to be difficult to achieve in this breed and remission-rate is low.
... Idiopathic epilepsy is the most common chronic neurological condition in dogs, with reported prevalence ranging from 0.5 to 5% (1)(2)(3). Of dogs with idiopathic epilepsy, 20-30% are refractory to treatment with standard antiepileptic medications, and less than half are able to maintain a seizure-free status without experiencing side effects (4,5). ...
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Idiopathic epilepsy is the most common chronic neurologic condition in dogs. Approximately 20–30% of those dogs are refractory to standard medical therapy and commonly experience side effects from antiepileptic drugs. Non-invasive vagus nerve stimulation (nVNS) has been frequently used in human medicine as an adjunct seizure therapy with low incidence of adverse events. Canine studies are limited to invasive surgical implants with no non-invasive evaluations currently published. We investigated the feasibility and efficacy of nVNS (gammaCore VET) as an adjunct treatment for refractory epilepsy in dogs. In total, 14 client-owned dogs completed the trial of either 8- or 16-week treatment periods during which they received 90–120 s stimulation three times per day in the region of the left cervical vagus nerve. Owners recorded seizure type (focal or generalized) and frequency as well as any adverse effects. Out of 14 dogs, nine achieved a reduction in seizure frequency and four were considered responders with a 50% or greater reduction in seizures from baseline to the final treatment period. However, there was no statistically significant difference in overall seizure frequency (p = 0.53) or percent change in seizure frequency between groups (p = 0.75). Adverse effects occurred in 25% of dogs originally enrolled, with reports of a hoarse bark and limb trembling, lethargy, behavioral changes, and an increase in seizure frequency. Non-invasive VNS was found to be safe and easy to administer with mild adverse events. It is considered a feasible treatment option as an adjunct therapy in refractory seizures and should be further investigated.
... Epilepsy is a common, chronic neurological disease affecting between 0.5per cent and 0.75per cent of dogs in the general population with a higher prevalence in some at-risk breeds. [1][2][3][4] Epilepsy is defined as two Veterinary Record (2020) doi: 10.1136/vr.105410 or more unprovoked epileptic seizures occurring at least 24 hours apart. ...
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Background Despite appropriate antiseizure drug (ASD) treatment, around two-thirds of dogs with idiopathic epilepsy (IE) have seizures long-term and 20–30per cent of affected dogs remain poorly controlled. Methods The current study aim is to test in a field trial the efficacy and tolerability of a commercially available diet enriched with 6.5per cent medium chain triglyceride (MCT) oil in dogs (n=21) with at least a tier 1 idiopathic epilepsy diagnosis, without cluster seizures, in 10 veterinary practices across Europe. Each dog’s quality of life (QoL), ataxia, sedation and frequency and severity of seizures were recorded by owners throughout the study. Results The mean seizure frequency per month, averaged over the entire 84-day study, significantly (P=0.04) decreased 32per cent compared with the baseline monthly seizure frequency recorded during the month immediately before feeding the diet. Similarly, the seizure days rate (days/month) also declined (P<0.001) by 42per cent. QoL was reported as very good to excellent (>8.5/10) in 20 of the 21 dogs before starting the diet and this remained unchanged during the trial. Conclusions This study demonstrates the use of a diet enriched with MCTs as an adjunct to ASD treatment may have some antiseizure properties for dogs diagnosed with IE, as demonstrated in previous studies.
... Epilepsy is the most common neurological disease in dogs (1)(2)(3)(4)(5)(6). An increasing number of gene defects have been discovered in canine seizure disorders (6,7), in which abnormal electrical activity arises from structurally intact neural tissue or a microstructurally deviant group of cells, which cannot be visualized in conventional MRI (8). ...
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Proton magnetic resonance spectroscopy (H1-MRS) could provide insight into the metabolic pathophysiology of the temporal lobe of canine brain after seizure. Currently, there is no evidence-based data available on MRS of temporal lobe in dogs with idiopathic epilepsy (IE). The aim of this prospective, cross-sectional study was to evaluate the interictal metabolic activity of the temporal lobe in IE dogs compared to a control group with the use of H1-MRS. Ten healthy dogs and 27 client-owned dogs with IE underwent 1.5-Tesla magnetic resonance imaging (MRI) and single-voxel H1-MRS. The MRS studies were acquired as spin echoes with a repetition time (TR) of 2,000 ms and an echo time (TE) of 144 ms. A cubic voxel (10 × 10 × 10 mm) was positioned bilaterally into the region of the left and right temporal lobe, including a middle part of the hippocampus and the amygdala. The N-acetylaspartate (NAA)-to-creatine (NAA/Cr), NAA-to-choline (NAA/Cho), choline-to-creatine (Cho/Cr), and choline-to-NAA (Cho/NAA) ratios were determined in both hemispheres and compared to controls. No significant differences in all metabolite ratios between epileptic dogs and the control group could be found. A time-dependent decrease in the NAA/Cho ratio as well as an increase in the Cho/NAA ratio was found with proximity in time to the last seizure. We found no correlation between metabolite ratios and age or sex in this animal group. Time span from the last seizure to the acquisition of MRS significantly correlated with NAA/Cho and Cho/NAA ratio. We conclude that without a time relation, metabolite ratios in dogs with IE do not differ from those of the control group.
... The current study revealed a higher incidence of epilepsy in male than in female as 0.91% (12/1314) and 0.84% (7/830) respectively. Supportive to these (Heske et al. 2014) [6] noticed that, males were at a higher risk (1.4:1) than females. Among the 30 breeds observed, 5 breeds showed epileptic condition with a highest incidence in Saint Bernard (1.14%, (2/69)) followed by German Shepherd (1.14%, (6/526)), Labrador (1.06%, (6/563)), Pomeranian (1.03%, (3/290)), and Non descript (0.51%, (2/386)). ...
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Epilepsy is one of the commonest disease conditions in dogs with characteristic clinical signs of episodic seizures. To find the incidence level of epilepsy on the aspects of age, sex, breed and season wise along with the evaluation of haematobiochemical values. Out of 2144 dogs observed 19 positive cases of epilepsy were found and an overall incidence of 0.88% was obtained. Eighteen dogs selected for the haematobiochemical study showed mean values in the normal range. Old dogs and male dogs having the higher incidence of epilepsy than the female. St. Bernard and Nondescript having the highest and lowest breed wise incidence respectively. The higher incidence of epilepsy showed by summer season with winter being the lowest.
... Epilepsy is the most common chronic neurological disorder of dogs [1], with an estimated prevalence of 0.75% in the general population [2]. Approximately half of affected dogs are diagnosed with idiopathic epilepsy, a clinical syndrome characterized by recurrent seizures for which there is no underlying cause other than a presumed genetic predisposition [3][4][5]. ...
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Background: Idiopathic epilepsy is a common neurological disorder of dogs characterized by recurrent seizures for which no underlying basis is identified other than a presumed genetic predisposition. The pathogenesis of the disorder remains poorly understood, but environmental factors are presumed to influence the course of disease. Within the growing body of research into the microbiota-gut-brain axis, considerable attention has focused on the protective role of Lactobacilli in the development and progression of neurological disease. Investigations into the association between the gut microbiome and epilepsy are in their infancy, but some preliminary findings support a role for Lactobacilli in drug resistant epilepsy. To date, there are no published studies evaluating the gut microbiome in dogs with epilepsy. This pilot study was undertaken to evaluate fecal Lactobacillus populations in dogs with idiopathic epilepsy compared to healthy dogs. Results: Fecal samples were obtained from 13 pairs of dogs, consisting of a drug-naïve epileptic dog and a healthy dog from the same household and maintained on the same diet. Evaluation of large-scale microbial patterns based on 16S rRNA gene amplicon sequencing identified a household effect in the study population. Differential prevalence testing at the 16S rRNA gene sequence variant and genus levels did not identify any statistically significant differences between epileptic and control dogs. Quantitative PCR of Lactobacillus species isolated through culture revealed no statistically significant difference between the epileptic and control dogs (median concentration, 3.8 log10 CFU/g feces and 4.6 log10 CFU/g feces, respectively). Lactobacillus in culture was not killed by exposure to phenobarbital, potassium bromide, zonisamide, or levetiracetam. Conclusions: This pilot study did not identify any difference in large-scale microbial patterns or relative or absolute abundance of Lactobacillus species in drug-naïve epileptic dogs compared to healthy dogs. Further studies are warranted to evaluate the role of the gut microbiome in disease progression and treatment response in dogs with epilepsy. Lactobacilli in culture were not killed or inhibited from growing when exposed to phenobarbital, potassium bromide, zonisamide or levetiracetam, suggesting that antiepileptic drug administration is less likely to be a confounding factor in future studies evaluating the role of Lactobacillus in epilepsy.
... Importantly, as several genetic disorders occur only in certain breeds, canine tissue banks should become able to collect and store samples from a large number of dogs, which represent a wide range of breeds. For example, epilepsy is highly prevalent in many breeds [57][58][59], indicating a strong genetic predisposition in these populations. ...
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Background: Dogs ( Canis familiaris ) are natural models of several human diseases, including age-related dementia. However, the molecular techniques, which are routinely applied in invertebrate and rodent models to study disease pathologies and mechanisms, has limited applicability in dogs, mainly because of ethical reasons. In the case of humans, the limited accessibility of tissue samples is at least partly solved by biobanks, which collect and store tissues and organs from voluntary donations. A similar approach with pet dogs could support both translational and veterinary research goals by providing access to good quality biological materials obtained from a wide range of dogs with known ancestry, life history and medical background. Therefore, we have established an initiative, the Canine Brain and Tissue Bank, to collect and store biological samples from pet dogs. Objectives: The molecular qualities of tissue samples collected and stored on a tissue bank are crucial for reliable downstream applications. We used quantitative Real-Time PCR methodology to assess the stability of mRNA content in our stored samples. Three previously validated reference genes, GAPDH , HMBS and HPRT1 were chosen as targets. Results: The tested reference genes showed expression patterns and stability values that were consistent with the literature. Conclusions: Based on the results, the molecular quality of tissues collected in the CBTB’s donations system can fit in the standards of dog gene expression analyses.
... As studies of the relationship between chronic disease using heterogeneous populations of diseased animals have not found significant results to date, idiopathic epilepsy (IE) has been chosen as the single disease of interest in this study. IE is a common chronic neurological disorder in dogs, characterised by recurrent seizure activity, and estimated to affect 0.6-.075% of dogs [25,26]. The BC breed is predisposed to a severe form of IE [27]. ...
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Hair is an emerging biological matrix in which to measure chronic HPA axis activity, offering a longer term view into an animal’s life. We explored effects of exogenous (e.g. lifestyle, medications, social environment) and endogenous (e.g. disease, behaviour) stressors on hair cortisol concentration (HCC) in a population of Border Collies (BCs). Owners of BCs were recruited and reported their dog’s lifestyle, clinical history, anxiety-related behaviour, and collected a white hair sample from their dog’s dorsal neck region. HCC was determined using established methods with a commercial cortisol assay kit. Samples from 135 BCs were analysed, with 91 healthy controls and 44 diagnosed with epilepsy as a model disease. Factors associated with higher HCC included psychosocial stressors (living with three or more other dogs) and lifestyle (engaging in competitive flyball); while factors associated with lower HCC included anxiety (stranger-directed and non-social), health (epilepsy diagnosis, with number of seizures to date negatively correlated with HCC) and medication (certain anti-epileptic drugs were associated with elevated or reduced HCC). These novel results highlight the potential of chronic stress with frequent or persisting HPA-axis hyperactivity leading to a state of hypocortisolism, and the need to consider stressor recency and recurrence when interpreting HCC data.
... Even when large clinical databases are used, the reported risk of disease can appear too high if the breed under investigation has a lower than average disposition for other diseases, and therefore is less frequently represented in the clinical database than in the source population. In recent years, a Swedish database of insured dogs has been used to compare breed predisposition to different diseases [25][26][27]. A limitation of using insured dogs as the reference is that the uninsured dogs are not included and there is a possibility that breeds with more health problems are more likely to be insured. ...
Article
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Background A retrospective case–control study was conducted to estimate breed predisposition for common orthopaedic conditions in 12 popular dog breeds in Norway and Sweden. Orthopaedic conditions investigated were elbow dysplasia (ED); cranial cruciate ligament disease (CCLD); medial patellar luxation (MPL); and fractures of the radius and ulna. Dogs surgically treated for the conditions above at the Swedish and Norwegian University Animal Hospitals between the years 2011 and 2015 were compared with a geographically adjusted control group calculated from the national ID-registries. Logistic regression analyses (stratified for clinic and combined) were used to calculate odds ratios (OR) and 95% confidence intervals. Mixed breed dogs were used as reference. Results Breeds found at-risk for ED were the Labrador retriever (OR = 5.73), the Rottweiler (OR = 5.63), the German shepherd dog (OR = 3.31) and the Staffordshire bull terrier (OR = 3.08). The Chihuahua was the only breed where an increased risk for MPL (OR = 2.80) was identified. While the Rottweiler was the only breed predisposed for CCLD (OR = 3.96), the results were conflicting for the Labrador retriever (OR = 0.44 in Sweden, 2.85 in Norway); the overall risk was identical to mixed-breed dogs. Conclusions Most results are in concordance with earlier studies. However, an increased risk of CCLD was not identified for the Labrador retriever, the Staffordshire bull terrier was found to have an increased risk of ED and some country-specific differences were noted. These results highlight the importance of utilising large caseloads and appropriate control groups when breed susceptibility is reported. Electronic supplementary material The online version of this article (10.1186/s13028-019-0454-4) contains supplementary material, which is available to authorized users.
... Bei bestimmten Rassen, wie z. B. Belgischer Schäferhund, Border Terrier und Labrador Retriever, können deutlich höhere Prävalenzen vorliegen [2]. Für Katzen wird der relative Anteil der mit Krampfanfällen vorgestellten Tiere mit 2,1 % angegeben [3]. ...
Article
Zusammenfassung Epilepsie ist eine neurologische Erkrankung, die dem Kleintierpraktiker im klinischen Alltag häufig begegnet. Die Erkrankung umfasst eine Vielzahl klinischer Ausprägungen und Ätiologien und die klinische Aufarbeitung bedarf in vielen Fällen einer kostenaufwendigen und umfangreichen Diagnostik. Diese ist notwendig, um eine metabolische Ursache für die Krampfanfälle festzustellen oder auszuschließen bzw. zwischen idiopathischer und struktureller Epilepsie unterscheiden zu können. Für die Klassifikation der Epilepsie ist die Untersuchung mittels Magnetresonanztomografie (MRT) ein zentraler Bestandteil der Diagnosefindung, die sich entscheidend auf Therapie und Prognose auswirkt. Die Standardisierung von MRT-Protokollen hat große Bedeutung, um eine einheitliche Untersuchung und vergleichbare Ergebnisse zu erzielen. Dies kann die Kommunikation und Interaktion zwischen klinischen Einrichtungen erleichtern und die Möglichkeit bieten, noch unerkannte strukturelle Veränderungen im MRT zu erfassen. Dieser Übersichtsartikel beschäftigt sich im Zentralen mit der Definition und Klassifikation der Epilepsie sowie der bildgebenden Diagnostik der Epilepsie beim Hund und nimmt Bezug auf Statistiken und Empfehlungen von Spezialisten zur klinischen Fallaufarbeitung.
... In the veterinary world, idiopathic epilepsy (IE) is a common neurological condition (Kearsley-Fleet et al., 2013;Heske et al., 2014). Some breeds show high disease prevalence or increased odds of having IE such as Belgian Shepherds, Border Terriers, Labradors and German Shepherd dogs (Kearsley-Fleet et al., 2013;Berendt et al., 2015;Hülsmeyer et al., 2015). ...
Article
Psychiatric comorbidities affect a large percentage of people with epilepsy and have a detrimental impact on their quality of life. Recently, behavioural comorbidities, with similar characteristics to human psychiatric diseases, have been identified in dogs with idiopathic epilepsy. In particular, behaviours motivated by the fear–anxiety emotional system have been found to be associated with the occurrence of idiopathic epilepsy in both dogs receiving anti-epileptic drugs, and drug-naïve dogs. There has been little research into the relationship between epilepsy and behavioural signs, and even less into potential treatment protocols. The following article will review available literature from human medicine to describe the current state of knowledge about the bi-directional relationship between anxiety and epilepsy, draw parallels from reported anxiogenic and anxiolytic properties of anti-epileptic drugs and attempt to provide pharmaceutical and behavioural guidance for veterinary patients with epilepsy and comorbid anxiety.
... Epilepsy is a common neurological disorder affecting 0.6-0.75% of dogs in veterinary practice (1,2). Treatment is complicated by the frequent occurrence of drug-resistant epilepsy in dogs with idiopathic epilepsy (3,4). ...
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Epilepsy is a common neurological disorder affecting 0.6–0.75% of dogs in veterinary practice. Treatment is frequently complicated by the occurrence of drug-resistant epilepsy and cluster seizures in dogs with idiopathic epilepsy. Only few studies are available to guide treatment choices beyond licensed veterinary drugs. The aim of the study was to compare antiseizure efficacy and tolerability of two add-on treatment strategies in dogs with drug-resistant idiopathic epilepsy. The study design was a prospective, open-label, non-blinded, comparative treatment trial. Treatment success was defined as a 3-fold extension of the longest baseline interseizure interval and to a minimum of 3 months. To avoid prolonged adherence to a presumably ineffective treatment strategy, dog owners could leave the study after the third day with generalized seizures if the interseizure interval failed to show a relevant increase. Twenty-six dogs (mean age 5.5 years, mean seizure frequency 4/month) with drug-resistant idiopathic epilepsy and a history of cluster seizures were included. Dogs received either add-on treatment with pregabalin (PGB) 4 mg/kg twice daily (14 dogs) or a dose increase in levetiracetam (LEV) add-on treatment (12 dogs). Thirteen dogs in the PGB group had drug levels within the therapeutic range for humans. Two dogs in the PGB group (14.3%; 2/14) and one dog in the LEV group (8.3%; 1/12) achieved treatment success with long seizure-free intervals from 122 to 219 days but then relapsed to their early seizure frequency 10 months after the study inclusion. The overall low success rates with both treatment strategies likely reflect a real-life situation in canine drug-resistant idiopathic epilepsy in everyday veterinary practice. These results delineate the need for research on better pharmacologic and non-pharmacologic treatment strategies in dogs with drug-resistant epilepsy.
... Idiopathic epilepsy (IE) is the most common chronic neurological disorder in dogs, defined as epilepsy with an unknown, genetic, or suspected genetic origin, 1 and affects 0.6% to 0.7% of dogs. 2,3 Although IE is by definition a seizure disorder in both dogs 1 and people, 4 IE is characterized by more than recurrent epileptic seizures alone. An influx of studies on IE in dogs over the past 30 years highlights the complexity of IE as a general brain disease in dogs. ...
Article
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Background: Epilepsy is the most common chronic neurological disease in dogs that adversely affects the quality of life (QoL) of affected dogs and their owners. Research on epilepsy in dogs is expanding internationally, but where best to focus limited research time, funds, and expertise to achieve better outcomes for affected dogs and their owners has not been studied. Objective: To explore idiopathic epilepsy (IE) research priorities of owners of dogs with IE, general practice veterinarians, and veterinary neurologists. Methods: An international online survey was conducted in 2016 and repeated in 2020. Participants rated the absolute importance and relative rank of 18 areas of IE research, which were compared between groups and time points. Results: Valid responses were received from 414 respondents in 2016 and 414 respondents in 2020. The development of new anti-seizure drugs (ASD) and improving the existing ASD management were considered the most important research priorities. Areas of research with increasing priority between 2016 and 2020 included non-ASD management, with the greatest potential seen in behavioral and dietary-based interventions. Disagreements in priorities were identified between groups; owners prioritized issues that impacted their and their dog's QoL, for example, adverse effects and comorbidities, whereas general practitioner vets and neurologists prioritized clinical issues and longer-term strategies to manage or prevent IE, respectively. Conclusions and clinical importance: Ensuring that voices of owners are heard in the planning of future research should be a broader goal of veterinary medicine, to target research efforts toward areas most likely to improve the QoL of the dog-owner dyad.
... Epilepsy is one of the most common chronic neurological conditions in dogs. Its prevalence has been estimated to be 0.6-0.75% for idiopathic only or idiopathic and structural forms, respectively, in the general dog population [1,2]. ...
Article
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Epilepsy is the most common chronic neurological disorder of dogs and requires a substantial commitment by the pet owner. The aim of this study was to evaluate how Italian owners of epileptic dogs receiving long-term treatment perceived their own quality of life (QoL) and that of their pet, using a list of key questions. A questionnaire was sent to owners of dogs affected by recurrent seizures and treated with antiepileptic drugs for at least three months. The questions included signalment, medical history and physical, social and psychological aspects associated with managing an epileptic dog. Eighty complete questionnaires were obtained. Most owners surveyed had a positive opinion on their dog’s QoL and they did not believe that commitment to managing their animals was a limitation of QoL. Dog QoL, seizure, frequency and severity were considered the most important factors in evaluating the efficacy of the antiepileptic treatment. The evaluation of the different aspects of QoL can help veterinary professionals understand the need for correct and exhaustive information provided to owners and the development of therapeutic plans and follow up, corresponding to the needs of dogs and owners.
... Epilepsy is not a single disease but a group of disorders characterized by a broad array of clinical signs, age of onset, and underlying causes (28). The true prevalence of epilepsy in dogs is unknown and has been estimated to be 0.6-0.75% in the general dog population (29,30), which is similar to the prevalence of epilepsy in humans (28). In certain dog breeds predisposed to idiopathic epilepsy, considerable higher prevalence rates are reported than those estimated for the general dog population, which is one of the reasons a genetic component is suspected in certain canine breeds (31). ...
Article
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Epilepsy is a common neurological disease in both humans and domestic dogs, making dogs an ideal translational model of epilepsy. In both species, epilepsy is a complex brain disease characterized by an enduring predisposition to generate spontaneous recurrent epileptic seizures. Furthermore, as in humans, status epilepticus is one of the more common neurological emergencies in dogs with epilepsy. In both species, epilepsy is not a single disease but a group of disorders characterized by a broad array of clinical signs, age of onset, and underlying causes. Brain imaging suggests that the limbic system, including the hippocampus and cingulate gyrus, is often affected in canine epilepsy, which could explain the high incidence of comorbid behavioral problems such as anxiety and cognitive alterations. Resistance to antiseizure medications is a significant problem in both canine and human epilepsy, so dogs can be used to study mechanisms of drug resistance and develop novel therapeutic strategies to benefit both species. Importantly, dogs are large enough to accommodate intracranial EEG and responsive neurostimulation devices designed for humans. Studies in epileptic dogs with such devices have reported ictal and interictal events that are remarkably similar to those occurring in human epilepsy. Continuous (24/7) EEG recordings in a select group of epileptic dogs for >1 year have provided a rich dataset of unprecedented length for studying seizure periodicities and developing new methods for seizure forecasting. The data presented in this review substantiate that canine epilepsy is an excellent translational model for several facets of epilepsy research. Furthermore, several techniques of inducing seizures in laboratory dogs are discussed as related to therapeutic advances. Importantly, the development of vagus nerve stimulation as a novel therapy for drug-resistant epilepsy in people was based on a series of studies in dogs with induced seizures. Dogs with naturally occurring or induced seizures provide excellent large-animal models to bridge the translational gap between rodents and humans in the development of novel therapies. Furthermore, because the dog is not only a preclinical species for human medicine but also a potential patient and pet, research on this species serves both veterinary and human medicine.
... Epilepsy is the most common neurological disorder in dogs. The prevalence in dogs in general has been estimated to around 0.76% (Heske et al. 2014). However, certain dog breeds suffer from genetic epilepsy causing a much higher prevalence (H€ ulsmeyer et al. 2015). ...
Article
The dog breed Petit Basset Griffon Vendeen has a relatively high prevalence of idiopathic epilepsy compared to other dog breeds and previous studies have suggested a genetic cause of the disease in this breed. Based on these observations, a genome‐wide association study was performed to identify possible epilepsy‐causing loci. The study included 30 unaffected and 23 affected dogs, genotyping of 170K SNPs, and data analysis using plink and emmax. Suggestive associations at CFA13, CFA24 and CFA35 were identified with markers close to three strong candidate genes. However, subsequent sequencing of exons of the three genes did not reveal sequence variations, which could explain development of the disease. This is, to our knowledge, the first report on loci and genes with a possible connection to idiopathic epilepsy in Petit Basset Griffon Vendeen. However, further studies are needed to conclusively identify the genetic cause of idiopathic epilepsy in this dog breed.
... Keywords: dog, first opinion, veterinary, antiepileptic drugs, epileptic seizures INTRODUCTION Canine idiopathic epilepsy (IE) is the most common chronic neurologic disease in dogs, with an estimated prevalence of 0.6-0.75% in the general canine population (1,2). Breed specific prevalence is often much higher, being as high as 20% in Belgian shepherds in the US and 33% in certain breeding lines in Denmark (3). ...
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The aims of this study are to gain insight on how primary care veterinarians in the UK diagnose and treat canine idiopathic epilepsy (IE) and what they perceive as challenges in the management of canine IE. Two hundred and thirty-five primary care veterinarians took part in this survey. The questionnaire asked about the type of practice the respondent worked in, any relevant post-graduate qualifications, how many years' experience they had in practice and the participant's canine IE caseload. Participants were asked how they diagnose canine IE, how they select antiseizure drugs (ASDs) and how they assess outcome. The questionnaire also explored which information sources they have access to for deciding on canine IE treatment, challenges that may be faced when managing these cases and areas in which more support can be provided. 94.5% of participants (n = 222/235) managed <10 canine IE cases in a year and 87.8% (n = 206/235) used phenobarbital as their first line ASD. The reported mean initial phenobarbital dose was 2.1 mg/kg (standard deviation = 0.71) every 12 h. When considering how closely participants aligned with IVETF guidelines on the topics of diagnosis, ASD initiation and outcome assessment, on average participants would score around half of the available points. 53.2% (n = 125/235) of respondents recommended neutering in canine IE and 46.8% (n = 110/235) did not. 53.2% (n = 125/235) did not recommend any additional treatments for canine IE beyond use of ASDs. 23.4% recommended Purina Neurocare diet (n = 55/235), 12.8% recommended environmental modification (n = 30/235), and 6.8% (n = 16/235) recommend medium chain triglyceride supplements. In this study participants found managing client expectations to be most challenging alongside canine IE emergency management. The main limitation of this study is the relatively low response rate and therefore the results may not reflect the entire small animal veterinary profession in the UK. However, the results of this study represent a starting point to inform educational resources and support strategies to improve quality care of canine IE in primary care.
... The domesticated dog (Canis familiaris) shares an evolutionary history with humans, and dogs are a promising model for the study of human behavior and disease [22][23][24]. Epilepsy is the most common neurological disorder in dogs [25], and naturally occurring canine epilepsy shares many features with human epilepsy [26]. Additionally, dogs are large enough to accommodate implanted devices designed for humans. ...
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Chronic brain recordings suggest that seizure risk is not uniform, but rather varies systematically relative to daily (circadian) and multiday (infradian) cycles. Here, one human and seven dogs with naturally occurring epilepsy had continuous intracranial EEG (median 298 days) using novel implantable sensing and stimulation devices. Two pet dogs and the human subject received concurrent thalamic deep brain stimulation (DBS) over multiple months. All subjects had circadian and infradian cycles in the rate of interictal epileptiform spikes (IES). There was seizure phase locking to circadian and infradian IES cycles in five and seven out of eight subjects, respectively. Thalamic DBS modified circadian (all 3 subjects) and infradian (analysis limited to the human participant) IES cycles. DBS modified seizure clustering and circadian phase locking in the human subject. Multiscale cycles in brain excitability and seizure risk are features of human and canine epilepsy and are modifiable by thalamic DBS.
... with gliomas representing 36%-70% of primary brain tumours in dogs. [14][15][16][17] The prevalence of idiopathic epilepsy in dogs has been estimated at 0.6%-0.75% in the general canine population, 18,19 while a study of recurrent seizure disorders in cats presented to primary care practices in the UK reported a 1-year period prevalence of 0.16%. 20 Thus, detailed analysis of feline and canine brain tissue can increase our understanding of such diseases and facilitate advances in both veterinary and potentially human medicine. ...
Article
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Background: Detailed analysis of archived brain tissue is fundamental to advancing the understanding of neurological disease. The development of the UK Brain Bank Network (UBBN) has provided an invaluable resource to facilitate such research in the human medical field. Similar resources are needed in veterinary medicine. However, collection and archiving of companion animal brain tissue is a potentially sensitive area for pet owners and veterinary professionals. Methods: Using an online survey, we aimed to study pet owners' perceptions of brain banking. The survey included information on respondents, their views on organ donation, the UBBN and the Royal Veterinary College's Companion Animal Brain Bank (RVC CABB). Results: In total 185 respondents were included. The use of brain tissue from pets for research was supported by 87% of respondents, and 66% of respondents felt that they were highly likely or likely to donate their pet's brain tissue to a CABB. Furthermore, 94% felt that more information on tissue banking in companion animals should be readily available. Conclusions: We found that the perceptions of companion animal brain banking were positive in our respondents. Open dialogue and clear information provision on the process and benefits of the CABB could enhance awareness and thus facilitate brain donation for translational research.
Article
Epilepsy is among the most dynamic disorders in neurology. A canonical view holds that seizures, the characteristic sign of epilepsy, occur at random, but, for centuries, humans have looked for patterns of temporal organization in seizure occurrence. Observations that seizures are cyclical date back to antiquity, but recent technological advances have, for the first time, enabled cycles of seizure occurrence to be quantitatively characterized with direct brain recordings. Chronic recordings of brain activity in humans and in animals have yielded converging evidence for the existence of cycles of epileptic brain activity that operate over diverse timescales: daily (circadian), multi-day (multidien) and yearly (circannual). Here, we review this evidence, synthesizing data from historical observational studies, modern implanted devices, electronic seizure diaries and laboratory-based animal neurophysiology. We discuss advances in our understanding of the mechanistic underpinnings of these cycles and highlight the knowledge gaps that remain. The potential clinical applications of a knowledge of cycles in epilepsy, including seizure forecasting and chronotherapy, are discussed in the context of the emerging concept of seizure risk. In essence, this Review addresses the broad question of why seizures occur when they occur.
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Resting-state functional Magnetic Resonance Imaging (rs-fMRI) has become an established technique in humans and reliably determines several resting state networks (RSNs) simultaneously. Limited data exist about RSN in dogs. The aim of this study was to investigate the RSNs in 10 healthy beagle dogs using a 3 tesla MRI scanner and subsequently perform group-level independent component analysis (ICA) to identify functionally connected brain networks. Rs-fMRI sequences were performed under steady state sevoflurane inhalation anaesthesia. Anaesthetic depth was titrated to the minimum level needed for immobili-sation and mechanical ventilation of the patient. This required a sevoflurane MAC between 0.8 to 1.2. Group-level ICA dimensionality of 20 components revealed distributed sensory, motor and higher-order networks in the dogs' brain. We identified in total 7 RSNs (default mode, primary and higher order visual, auditory, two putative motor-somatosensory and one putative somatosensory), which are common to other mammals including humans. Identified RSN are remarkably similar to those identified in awake dogs. This study proves the feasibility of rs-fMRI in anesthetized dogs and describes several RSNs, which may set the basis for investigating pathophysiological characteristics of various canine brain diseases.
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Background Extended‐release levetiracetam (LEV‐XR) has gained acceptance as an antiepileptic drug in dogs. No studies have evaluated its disposition in dogs with epilepsy. Hypothesis/Objectives To evaluate the pharmacokinetics of LEV‐XR in epileptic dogs when administered alone or with phenobarbital or zonisamide. Animals Eighteen client‐owned dogs on steady‐state maintenance treatment with LEV‐XR (Group L, n = 6), LEV‐XR and phenobarbital (Group LP, n = 6), or LEV‐XR and zonisamide (Group LZ, n = 6). Methods Pharmacokinetic study. Blood samples were collected at 0, 2, 4, 8, and 12 hours after LEV‐XR was administered with food. Plasma LEV concentrations were determined by high‐pressure liquid chromatography. A population pharmacokinetic approach and nonlinear mixed effects modeling were used to analyze the data. Results Treatment group accounted for most of the interindividual variation. The LP group had lower CMAX (13.38 μg/mL) compared to the L group (33.01 μg/mL) and LZ group (34.13 μg/mL), lower AUC (134.86 versus 352.95 and 452.76 hours·μg/mL, respectively), and higher CL/F (0.17 versus 0.08 and 0.07 L/kg/hr, respectively). The half‐life that defined the terminal slope of the plasma concentration versus time curve (~5 hours) was similar to values previously reported for healthy dogs. Conclusions and Clinical Importance Considerable variation exists in the pharmacokinetics of LEV‐XR in dogs with epilepsy being treated with a common dose regimen. Concurrent administration of phenobarbital contributed significantly to the variation. Other factors evaluated, including co‐administration of zonisamide, were not shown to contribute to the variability. Drug monitoring may be beneficial to determine the most appropriate dose of LEV‐XR in individual dogs.
Article
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Epilepsy is the most common chronic neurological disorder in dogs and the almost lifelong administration of anti-epileptic drugs (AEDs) is recognized as the most successful treatment in veterinary medicine. Current pharmacological therapies for epilepsy have shown undesirable side effects. The dietary use of cannabidiol (CBD) in humans has shown therapeutic potential for the treatment of epileptic seizures. We administered CBD for 8 weeks to three dogs with epileptic seizures; decrease in the seizure interval was observed in two dogs, while one dog showed no improvement. Regarding the owners’ impressions, one reported considerable symptom improvement, one that the symptoms improved, and one that the symptoms remained unchanged.
Article
There are sparse published scientific data on associations between neutering and the severity and survival of dogs with idiopathic epilepsy. This study aimed to explore the timing of neutering with respect to onset of seizures in dogs with idiopathic epilepsy. Associations between neutering and both age of onset of seizures and the occurrence of cluster seizures or status epilepticus were examined. Survival analysis investigated the effects of sex-neuter categories. The median survival time of Border collies was compared with data previously reported in literature. The study included veterinary primary-care clinical data on 117 Labrador retrievers and 57 Border collies diagnosed with idiopathic epilepsy from the VetCompass project in the UK. The majority (74.2%; P ≤ 0.001) of neutered cases were neutered before the onset of seizures. Age (years) at onset of seizures did not differ between dogs intact at time of onset and dogs neutered before onset of seizures (males 3.6 vs. 3.7; P = 0.468 and females 3.4 vs. 4.1; P = 0.154). Neuter status was not associated with the occurrence of cluster seizures (males P = 0.947 and females P = 0.844). Dogs intact at onset of seizures had longer median survival times than dogs neutered before onset of seizures (males, 1436 days vs. 1234 days; P = 0.019; females, 1778.5 days vs. 1261 days; P = 0.027). Median survival time of 1393 days for Border collies was longer than previously reported (P ≤ 0.001). These results do not support recommendations to neuter dogs with idiopathic epilepsy within an evidence-based treatment plan.
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To evaluate the localization of functional deficit area in epileptogenic zones of the brain in seven refractory and seven non-refractory epilepsy dogs using technetium 99m labeled with ethyl cysteinate dimer and interictal single photon emission computed tomography [99mTc-ECD SPECT] co-registration with Magnetic Resonance Imaging (MRI). Regions showing perfusion deficits in the SPECT images were analyzed by using the standard semiquantitative evaluation method to compare the level of cortical perfusion to the maximum number of counts within the cerebellum (max C), considered the area of reference. This study showed that SPECT imaging revealed abnormalities in several regions of the brain in both epilepsy groups. The refractory epilepsy dogs showed more frequency area of hypoperfusion in temporal lobe than non-refractory group with not statistically significance (P=0.28). The result suggests the lesion in temporal might be relevance with refractory epilepsy in canine patients.
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Background Medium‐chain triglyceride (MCT) enriched diet has a positive effect on seizure control and behavior in some dogs with idiopathic epilepsy (IE). Objective To evaluate the short‐term efficacy of MCTs administered as an add‐on dietary supplement (DS) to a variable base diet to assess seizure control and antiseizure drug's (ASD) adverse effect profiles. Animals Twenty‐eight dogs with International Veterinary Epilepsy Task Force Tier II (IVETF) level diagnosis of treated IE with 3 or more seizures in the last 3 months were used. Methods A 6‐month multicenter, prospective, randomized, double‐blinded, placebo‐controlled crossover trial was completed, comparing an MCT‐DS with a control‐DS. A 9% metabolic energy‐based amount of MCT or control oil was supplemented to the dogs' diet for 3 months, followed by a control oil or MCT for another 3 months, respectively. Dogs enrolled in this study satisfied most requirements of IE diagnosis stated by the IVETF II level. If they received an oil DS or drugs that could influence the metabolism of the investigated DS or chronic ASD, the chronic ASD medication was adjusted, or other causes of epilepsy were found, the dogs were excluded from the study. Results Seizure frequency (median 2.51/month [0‐6.67] versus 2.67/month [0‐10.45]; P = .02) and seizure‐day frequency were significantly (1.68/month [0‐5.60] versus 1.99/month [0‐7.42], P = .01) lower when dogs were fed MCT‐DS in comparison with the control‐DS. Two dogs were free of seizures, 3 had ≥50% and 12 had <50% reductions in seizure frequency, and 11 dogs showed no change or an increase in seizure frequency. Conclusions and Clinical Importance These data show antiseizure properties of an MCT‐DS compared to a control oil and support former evidence for the efficacy of MCTs as a nutritive, management option for a subpopulation of drug‐resistant dogs with epilepsy.
Article
Background Quantitative magnetic resonance imaging (MRI) is used to study the anatomy of the brain in dogs with idiopathic epilepsy. Purpose To quantitate MRI images in terms of volumetric ratios and histogram analyses of the following regions of interest (ROI) in dogs with idiopathic epilepsy: frontal; parietal; temporal; piriform; thalamic; and hippocampal regions. Material and Methods Nine dogs with epilepsy and four healthy controls were evaluated. We examined the volumetric ratios and histogram analyses of six ROIs in all dogs. Results MR images, in T1-weighted, T2-weighted, FLAIR, diffusion-weighted imaging, and apparent diffusion coefficient sequences detected changes in 4/9 (44%) epileptic dogs found in 5/6 regions: frontal; parietal; temporal; piriform; and hippocampal regions. However, no such changes were observed in the thalamic region. Interestingly, the frontal and piriform volumetric ratios of epileptic dogs were significantly lower than those of control dogs. The histogram analyses in 4/6 regions were significantly increased in epileptic dogs. Conclusion Our results demonstrated MRI finding abnormalities in several regions of the brain in several sequences including T1-weighted, T2-weighted, FLAIR, diffusion-weighted imaging, and apparent diffusion coefficient in epileptic dogs. In several regions of the brain, atrophy may exist, and hyperintensity may be present on MR images in epileptic dogs. These findings suggest that the diagnostic yield of MRI, which is an advanced neuroimaging technique, is high in epileptic dogs and has good reliability and sensitivity in detecting abnormal areas in patients.
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Chronic brain recordings suggest that seizure risk is not uniform, but rather varies systematically relative to daily (circadian) and multiday (multidien) cycles. Here, one human and seven dogs with naturally occurring epilepsy had continuous intracranial EEG (median 298 days) using novel implantable sensing and stimulation devices. Two pet dogs and the human subject received concurrent thalamic deep brain stimulation (DBS) over multiple months. All subjects had circadian and multiday cycles in the rate of interictal epileptiform spikes (IES). There was seizure phase locking to circadian and multiday IES cycles in five and seven out of eight subjects, respectively. Thalamic DBS modified circadian (all 3 subjects) and multiday (analysis limited to the human participant) IES cycles. DBS modified seizure clustering and circadian phase locking in the human subject. Multiscale cycles in brain excitability and seizure risk are features of human and canine epilepsy and are modifiable by thalamic DBS.
Chapter
Machine learning is being used in the prediction of health and disease status in the animals and has wide scale application in the animal health care and well-being and veterinary sciences. In this chapter we have highlighted some of the applications of machine learning in the health and disease prediction in animals. Although the applications are at its infancy, the future scope of such application science in this domain of biology is immense and needs to be exploited more in the welfare of animal life.
Article
Objective: To determine the prevalence of presumed postictal changes (PC) on brain MRI in epileptic dogs, describe their distribution, and recognize possible correlations with different epilepsy features. Animals: 540 client-owned dogs with epilepsy and a complete medical record that underwent brain MRI at 4 veterinary referral hospitals between 2016 and 2019. Procedures: Data were collected regarding signalment, seizure type, seizure severity, time between last seizure and MRI, and etiological classification of epilepsy. Postictal changes were considered when solitary or multiple intraparenchymal hyperintense lesions were observed on T2-weighted and fluid-attenuated inversion recovery images and were hypointense or isointense on T1-weighted sequences, which were not confined to a vascular territory and showed no to mild mass effect and no to mild contrast enhancement. Results: Sixty-seven dogs (12.4%) showed MRI features consistent with PC. The most common brain sites affected were the piriform lobe, hippocampus, temporal neocortex, and cingulate gyrus. Dogs having suffered cluster seizures or status epilepticus were associated with a higher probability of occurrence of PC, compared to dogs with self-limiting seizures (OR 2.39; 95% confidence interval, 1.33 to 4.30). Suspected PC were detected both in dogs with idiopathic epilepsy and in those with structural epilepsy. Dogs with unknown-origin epilepsy were more likely to have presumed PC than were dogs with structural (OR 0.15; 95% confidence interval, 0.06 to 0.33) or idiopathic epilepsy (OR 0.42; 95% confidence interval, 0.20 to 0.87). Time between last seizure and MRI was significantly shorter in dogs with PC. Clinical relevance: MRI lesions consistent with PC were common in epileptic dogs, and the brain distribution of these lesions varied. Occurrence of cluster seizures or status epilepticus, diagnosis of unknown origin epilepsy, and lower time from last seizure to MRI are predictors of suspected PC.
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Epilepsy is one of the most common chronic, neurological diseases in humans and dogs and considered to be a network disease. In human epilepsy altered functional connectivity in different large-scale networks have been identified with functional resting state magnetic resonance imaging. Since large-scale resting state networks have been consistently identified in anesthetised dogs' application of this technique became promising in canine epilepsy research. The aim of the present study was to investigate differences in large-scale resting state networks in epileptic dogs compared to healthy controls. Our hypothesis was, that large-scale networks differ between epileptic dogs and healthy control dogs. A group of 17 dogs (Border Collies and Greater Swiss Mountain Dogs) with idiopathic epilepsy was compared to 20 healthy control dogs under a standardized sevoflurane anaesthesia protocol. Group level independent component analysis with dimensionality of 20 components, dual regression and two-sample t test were performed and revealed significantly increased functional connectivity in the anterior default mode network of idiopathic epileptic dogs compared to healthy control dogs (p = 0.00060). This group level differences between epileptic dogs and healthy control dogs identified using a rather simple data driven approach could serve as a starting point for more advanced resting state network analysis in epileptic dogs.
Article
Background This study aims to investigate the perspectives of veterinarians in first-line practice on confidence and satisfaction regarding several important aspects of the description, diagnosis and treatment of canine patients with epilepsy. Methods A web-based questionnaire was used, focussing on general aspects of canine epilepsy, diagnostic tests, treatment and communication with owners. Results One hundred and two questionnaires were evaluated. No less than 73 per cent of veterinarians had performed euthanasia on one or more patients with epilepsy as the main reason. First-line veterinarians scored confidence on general aspects of epilepsy as 6 or 7 out of 10. Confidence regarding communication with owners was scored 7 or 8 out of 10. Conclusions This study provides insight into perspectives of Dutch veterinarians in first-line practice regarding canine epilepsy. Several results may provide reasons to adjust (pregraduate or postgraduate) education of veterinarians with regard to management of canine patients with epilepsy. Several factors (such as the importance of diagnostic imaging) may help specialists in the field communicate better with referring veterinarians so that first-line practitioners become better equipped in managing patients with epilepsy. These steps may then positively influence treatment results as well as care-giver burden for the first-line practitioner.
Article
Background: Idiopathic epilepsy (IE) is the most common cause of repeated seizures in dogs. The International Veterinary Epilepsy Task Force consensus guidelines recommend performing magnetic resonance imaging (MRI) of the brain and cerebrospinal fluid (CSF) analysis as part of a tier II diagnosis of IE, and these procedures have documented risks. The aim of this retrospective study was to identify how often dogs with suspected IE have abnormalities on CSF analysis. Methods: Dogs aged between 6 months and 6 years that were presented with a history of two or more seizures with at least 24 h between seizure episodes, a normal neurologic examination, no evidence of toxic or metabolic causes, a normal MRI scan (including contrast administration) and CSF analysis were included. Results: Eighty-two dogs were included. Of these, nine dogs (10.9%) had abnormalities on CSF analysis: five of nine dogs (55.5%) had albuminocytologic dissociation, three of nine dogs (33.3%) had mild increases in total nucleated cell count (TNCC), and one of nine dogs (11.1%) had mild increase in both total protein and TNCC. Cytology in dogs with elevated TNCC revealed a mononuclear pleocytosis. One of the nine dogs with abnormal CSF had a seizure within the 24 h before investigations, and six of nine dogs had a seizure within 1 month before investigation. Conclusion: CSF analysis can play an important role in the diagnostic investigation of the underlying causes of repeated seizures. However, in dogs with a normal inter-ictal neurological examination and MRI scan, it rarely reveals significant abnormalities, and the risk of performing a CSF tap may outweigh the potential diagnostic gain.
Article
Objectives The primary objective of this study was to investigate the prevalence of epileptic seizures and of presumed idiopathic epilepsy (PIE, describing epilepsy of unknown origin) in a cohort of British Shorthair (BSH) cats in Sweden. The secondary objective was to describe epileptic seizure characteristics and outcome for cats with PIE. Methods Owners of BSH cats born between 2006 and 2016 and registered with SVERAK (the Swedish Cat Clubs’ National Association) were invited to reply to a questionnaire about their cat’s general health. Owners who indicated that their cat had experienced epileptic seizures were invited to participate in an in-depth telephone interview about the epileptic seizures. The clinical characteristics of epileptic seizures in BSH cats were determined from the results of the interview. Results In this population comprising 1645 BSH cats (representing 28% of registered BSHs), the prevalence of epileptic seizures was 0.9% and for PIE it was 0.7%. BSH cats with PIE presented with infrequent but consistent epileptic seizures. Twenty-seven percent of BSH cats with epileptic seizures had cluster seizures but none presented with status epilepticus. None of the BSH cats was treated with antiepileptic drugs, and none of the owners reported epileptic seizure remission in their cat. Conclusions and relevance The prevalence of PIE in this population of BSH cats was 0.7%. The prevalence of epileptic seizures was 0.9%. In general, PIE in the BSH cat displayed a relatively benign phenotype where progression of epileptic seizures was uncommon.
Article
Seizures are a common emergency presentation to veterinary practice and can be challenging cases to treat and nurse. There are a large variety of underlying causes for seizures in companion animals, and nursing care can vary depending on the differential diagnoses. Nursing interventions such as seizure plans, intravenous catheter placement and constant rate infusions can all help to provide a rewarding outcome for both the nurse and the patient.
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Background: Although seizures are common in dogs, limited published information is available on the classifications of seizures, diagnostic approaches, or clinical management of seizure-affected patients in the veterinary primary care setting. Objectives: Explore seizure etiology, diagnostic testing, and clinical management of seizure-affected dogs in the primary care veterinary setting. Animals: A total of 455 553 dogs in VetCompass. Methods: Cross-sectional analysis by cohort clinical data. Results: From 2834 incident seizure cases, we identified 579 (20.5%) dogs with epilepsy based on the International Veterinary Epilepsy Task Force (IVETF) classification system, including 484 (17.1%) with idiopathic epilepsy, 95 (3.4%) with structural epilepsy, and 179 dogs (6.3%) with reactive seizures. In their clinical first opinion records, 245 (8.6%) cases were recorded with epilepsy. Overall, 1415 (49.9%) cases received diagnostic evaluation equivalent to or higher than IVETF Tier 1 diagnostic testing. Being <12 years of age and being insured were risk factors for receiving IVETF Tier 1 or higher diagnostic evaluation among seizure cases. Anti-seizure drug (ASD) treatment was not prescribed for 1960/2834 (69.2%) dogs in association with the incident seizure event. Of the remainder, 719 (25.3%) dogs received 1 ASD, whereas 155 (5.5%) an ASD combination. Conclusion and clinical importance: The differences between seizure classifications in the clinical records and those retrospectively assigned by the researchers support the need for clearer diagnostic guidelines in clinical practice. Insured dogs and dogs <12 years of age were more likely to receive advanced diagnostic evaluation, suggesting that financial and perceived prognostic factors influence case management.
Article
Background: Atopic dermatitis (AD) is considered to be a systemic disease in people shown to have an association with epilepsy. However, so far, no data about the association of epilepsy and atopy have been reported in dogs. Objectives: Given the homology between human and canine AD, and the increased incidence of epilepsy in atopic people, we investigated the association between AD and seizure-associated activity in a small canine population. Animals: We included 34 atopic dogs and 34 breed- and age range-matched nonatopic dogs. Methods and materials: We investigated the association between canine AD and signs of seizures in a retrospective, breed- and age range-matched, case-controlled study. Dog owners were interviewed using a standardized questionnaire. The presence or absence of signs of seizure activity and possible comorbidities were questioned. Results: Seven of the 34 atopic dogs also suffered from seizure activity. By contrast, only one dog affected with seizure signs could be identified among the 34 nonatopic dogs. Atopic dermatitis was associated with a higher frequency of seizure activity (McNemar test, P = 0.035; one-sided) and atopic dogs had a higher odds ratio to develop seizures [(95% CI) 7 (0.9-56.9)] compared to the age- and breed-matched nonatopic control group. No other comorbidities were detected. Conclusion and clinical importance: In our small retrospective study, we observed an increased prevalence of seizure activity in the atopic dog population. Further larger and prospective studies are needed to confirm these results.
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Cruciate ligament rupture (CLR) is a common orthopedic disorder in dogs. The study objectives were to evaluate incidence rate (IR), cause-specific mortality rate (CSMR) and risk factors for CLR in insured dogs. A single cohort study of dogs insured in Agria Pet Insurance in Sweden (2011–2016) was performed. Age at diagnosis, IR, CSMR and relative risk (RR) for CLR was calculated overall and per breed. The cohort included just over 600,000 dogs. The IR of CLR was 23.8 (95% confidence interval, 23.1–24.6) cases per 10,000 DYAR. The breeds with highest RR of CLR were Boerboel and Dogo Canario, while the breeds with lowest RR were Standard Dachshund and Miniature Pinscher. Dogue de Bordeaux had highest RR of euthanasia due to CLR. The median age at veterinary care claim for CLR was 7.1 (range 0.3–16.0) years and 6.6 (0.3–12) years at life insurance settlement. Large and giant breeds were generally diagnosed and euthanized due to CLR at a younger age compared to smaller breeds. The majority of the breeds with increased RR of CLR diagnosis and CLR-related euthanasia were large or giant. A pattern of increasing size and decreasing age at diagnosis/CLR-related euthanasia was observed.
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Idiopathic epilepsy (IE) is the most common chronic neurological condition in dogs, characterised by recurrent seizure activity and associated with negative behavioural and cognitive changes. We hypothesised that IE would negatively impact putative affective state, with dogs with IE exhibiting a more pessimistic judgement bias and more negative attention bias than controls. Dogs were tested in a previously-validated spatial judgement bias task, and a novel auditory attention bias task testing attention to sounds with different valence or salience (neutral, novel pre-habituated, threatening). Sixty-eight dogs (IE = 33, Control = 35) were tested, of which n = 37 acquired the spatial discrimination and responses to judgement bias probes were tested (IE = 19, Control = 18), and n = 36 were tested for responses to sounds (IE = 20, Control = 16). Study groups did not significantly differ by age, sex, breed or neuter-status (p > 0.05). Main effects of study group were not significant in judgement bias (F1,102 = 0.20, p = 0.658) or attention bias tasks (F3,102 = 1.64, p = 0.184). In contrast with our hypotheses, there was no evidence that IE altered cognitive biases in this study population; however, dogs with IE were significantly more likely to be unable to learn the spatial discrimination task (p = 0.019), which may reflect IE-related cognitive deficits. Developing methods to test affective state without excluding cognitively impaired individuals is a future challenge for animal welfare science.
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There has been much interest in utilizing the dog as a genetic model for common human diseases. Both dogs and humans suffer from naturally occurring epilepsies that share many clinical characteristics. Investigations of inherited human epilepsies have led to the discovery of several mutated genes involved in this disease; however, the vast majority of human epilepsies remain unexplained. Mouse models of epilepsy exist, including single-gene spontaneous and knockout models, but, similar to humans, other, polygenic models have been more difficult to discern. This appears to also be the case in canine epilepsy genetics. There are two forms of canine epilepsies for which gene mutations have been described to date: the progressive myoclonic epilepsies (PMEs) and idiopathic epilepsy (IE). Gene discovery in the PMEs has been more successful, with eight known genes; six of these are orthologous to corresponding human disorders, while two are novel genes that can now be used as candidates for human studies. Only one IE gene has been described in dogs, an LGI2 mutation in Lagotto Romagnolos with a focal, juvenile remitting epilepsy. This gene is also a novel candidate for human remitting childhood epilepsy studies. The majority of studies of dog breeds with IE, however, have either failed to identify any genes or loci of interest, or, as in complex mouse and human IEs, have identified multiple QTLs. There is still tremendous promise in the ongoing canine epilepsy studies, but if canine IEs prove to be as genetically complex as human and murine IEs, then deciphering the bases of these canine epilepsies will continue to be challenging.
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The Belgian shepherd Groenendael and Tervueren is believed to be at higher risk of developing epilepsy than dogs of the common population. This epidemiological study was designed to estimate the prevalence of epilepsy in the Danish population of Groenendael and Tervueren born between 1995 and 2004. Furthermore, it was the intention to describe the clinical manifestation (seizure types and phenomenology) of epilepsy and to identify risk factors for euthanasia once the dog was diagnosed as having epilepsy. All owners of Groenendael and Tervueren dogs born between January 1995 and December 2004 and registered in the Danish Kennel Club (1,248 dogs) were contacted and asked to answer a mailed questionnaire concerning epilepsy. Positive responders were subsequently validated in a follow-up interview conducted by telephone using a standardized questionnaire. Owners were questioned about age at first seizure, seizure frequency, seizure duration, a detailed description of seizure phenomenology, post-ictal signs and if a veterinarian had diagnosed the dog with epilepsy. Prevalence of epilepsy was estimated at 9.5%. Mean age of epilepsy debut was 3.3 years (range 0.5-8.0 years). There was an almost equal number of Groenendael (25) and Tervueren (24). The distribution of females and males was 31 and 18 respectively. Twenty-five per cent experienced focal seizures, 53% experienced focal seizures with secondary generalization and 18% experienced primary generalized seizures. In four percent seizures were unclassifiable. The most commonly reported focal seizure phenomenology included ataxia, crawling, swaying, fearful behavior, salivation, excessive attention seeking and disorientation. In 16% of the cases, epilepsy led to euthanasia. Intact dogs with epilepsy had a significantly increased risk of being euthanized because of epilepsy compared to neutered dogs with epilepsy. In 22% of the cases the owners reported that anxiety/hyperactivity/stress could act as a seizure provoking factor. A high prevalence of epilepsy appears to be present in the Danish Groenendael and Tervueren population. The relatively late debut age of epilepsy in this breed contributes greatly to the increased prevalence of epileptic individuals, because dogs developing epilepsy late in life are used for breeding unintended.
Article
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Data on over 222,000 Swedish dogs enrolled in life insurance in 1992 and 1993 were analysed. There were approximately 260 deaths per 10,000 dog-years at risk. Breed-specific mortality rates and causes of death are presented for breeds with more than 500 dogs at risk that had consistently high or low rates. Breed-specific mortality ranged from less than 1 per cent to more than 11 per cent. True rates and proportional statistics for the cause of death were calculated for the entire insured population (250 breeds) and cause-specific mortality rates were calculated for the breeds with the highest risk of dying of the most common causes. Trauma, tumours and problems related to the locomotor system together accounted for more than 40 per cent of all deaths or euthanasias. Although limited to insured dogs, these data cover approximately one-third of all Swedish dogs and provide baseline mortality data for further population-based studies on health and disease.
Article
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More than 200,000 dogs insured by one Swedish company at the beginning of either 1995 or 1996 were included in a retrospective, cross-sectional study. They could be covered for veterinary care at any age, but were eligible for life insurance only up to 10 years of age. Accessions for veterinary care that exceeded the deductible cost were used to calculate the risk of morbidity. The morbidity and mortality data have been stratified by gender, age, breed, location and human population density. In each year, 13 per cent of the dogs experienced at least one veterinary care event and the mortality risk was 3.0 per cent. The risk of morbidity varied with age, gender, breed, and location. The risk of mortality increased principally with age. It was possible to derive population-based risks of morbidity and mortality from these insurance data.
Article
To evaluate the prevalence of cluster seizures and status epilepticus in dogs with idiopathic epilepsy and determine risk factors for cluster seizure frequency, severity and patient outcome. Retrospective review of medical records of 407 dogs with idiopathic epilepsy was made. Follow-up questionnaires were evaluated in cases with cluster seizures. Mean age at diagnosis of idiopathic epilepsy was 4 years. Cluster seizures were documented in 169 (41%) dogs. German shepherds and boxers were significantly (P=0·04 and 0·01, respectively) more likely to suffer from cluster seizures compared to Labrador retrievers. There was no association between the occurrence of status epilepticus and cluster seizures and frequency and severity of cluster seizures and status epilepticus episodes with age or breed. Intact males were twice as likely (P=0·003) than neutered dogs to suffer from cluster seizures. Intact females had significantly (P=0·007) more frequent cluster seizures than neutered dogs. The median survival time for all dogs with cluster seizures was 95 months. Significantly (P=0·03) more dogs with frequent cluster seizures were euthanased because of the cluster seizures. There was a high prevalence of cluster seizures in dogs with idiopathic epilepsy. Neutering status appears to influence cluster seizure occurrence with intact females more likely to experience more frequent episodes. Euthanasia is associated with frequency of cluster seizure episodes.
Article
Background:Idiopathic childhood epilepsies with benign outcomes are well recognized in human medicine, but are not reported in veterinary literature. We recognized such a neurologic syndrome in Lagotto Romagnolo dogs.Animals: Twenty-five Lagotto Romagnolo puppies from 9 different litters examined because of simple or complex focal seizures and 3 adult Lagotto Romagnolo dogs exhibiting similar clinical signs were used.Methods: Clinical and diagnostic evaluations of affected dogs were conducted, including electromyography, electroencephalography, and other testing.Results: Seizures in puppies began at 5 to 9 weeks of age and usually resolved spontaneously by 8 to 13 weeks. Those with the most severe seizures also had signs of neurologic disease between these seizures, including generalized ataxia and hypermetria. There were no abnormalities in routine laboratory screenings of blood, urine, and cerebrospinal fluid. Electromyography, brainstem auditory-evoked potentials, and magnetic resonance imaging revealed no specific and consistent abnormalities. Fourteen of 16 (87.5%) affected puppies and 2 of 3 (67%) adult dogs revealed epileptiform activity in the electroencephalogram. Histopathologic examination in 1 puppy and 1 adult dog revealed lesions of Purkinje cell inclusions and vacuolation of their axons restricted to the cerebellum. Pedigree analysis suggests an autosomal recessive mode of inheritance.Conclusions and Clinical Importance: This disorder, with simple or complex focal seizures and cerebellar lesions, represents a newly recognized epileptic syndrome in dogs.
Article
Data are presented from some 321 Keeshond dogs attending a clinic for electroencephalographic records, and their 108 close ancestors. They are examined to see whether the EEG readings are diagnostic of a tendency to epileptiform fits, and what hereditary basis there is, if any, for both the readings and the fits. The evidence does not support the idea of a diagnostic value; finds no hereditary basis for the readings; and, as far as the limited information about dogs which have had fits allows, slightly favours some hereditary component in the aetiology of epilepsy. These findings are discussed in relation to those concerning hereditary epilepsy in other breeds.
Article
The aetiology and outcome of dogs with juvenile-onset seizures were investigated. One hundred and thirty-six dogs whose first seizure occurred before the age of one year were investigated. One hundred and two dogs were diagnosed with idiopathic epilepsy (IE), 23 with symptomatic epilepsy (SE), nine with reactive seizures (RS) and two with probable symptomatic epilepsy (pSE). The outcome was known in 114 dogs; 37 per cent died or were euthanased as a consequence of seizures. The mean survival time of this population of dogs was 7.1 years. Factors that were significantly associated with survival outcome included the diagnosis of SE and the number of antiepileptic drugs (AEDs) used before investigation. The use of one AED before investigation and a diagnosis of SE were associated with a negative outcome, whereas receiving no AED medications before referral was associated with a longer survival. For dogs with IE, survival time was shortened if the dog was a border collie or with a history of status epilepticus;receiving no AEDs before referral in the IE group was associated with a positive outcome. Seizure-free status was achieved in 22 per cent of dogs diagnosed with IE. While the survival times were longer than previously reported in canine epilepsy, similar remission rates to those reported in childhood epilepsy, where a 70 per cent remission rate is documented, were not seen in the canine juvenile population.
Article
Epilepsy with a genetic background is increasingly being identified. In certain dog breeds, epilepsy occurs with a higher prevalence than the estimate of 1-2% reported in the general dog population. The Petit Basset Griffon Vendeen (PBGV) experiences an increased occurrence of epilepsy compared to the general dog population. The target population consisted of all 876 PBGV dogs registered in the Danish Kennel Club from January 1, 1999 to December 31, 2008. The study population included 820 dogs that met the inclusion criteria. A population study was conducted to estimate the prevalence of epilepsy in the Danish PBGV population. A mailed questionnaire was used to detect possible signs of epilepsy. The information was subsequently validated by telephone interviews of positive and possible positive responders and a negative responder control group, using an extensive questionnaire developed to detect epilepsy. Dogs evaluated as epilepsy positive after the telephone interview were offered a clinical investigation. The prevalence of epilepsy was estimated to be 8.9% (42/471) in the PBGV population. Average age of onset was 26.3 months. Sex and mode of response did not affect the prevalence, but a strong litter effect was seen. Among euthanized dogs, epilepsy was the predominant cause (6/45 = 13.3%). Petit Basset Griffon Vendeen dogs experience an increased risk of epilepsy characterized by a relatively early onset and dominated by focal seizures with and without secondary generalization. With an estimated prevalence of 8.9% and substantial clustering within litters, a genetic factor associated with epilepsy is suspected.
Article
In this study, previously unreported cohort characteristics and seizure patterns for canine epilepsy were identified from a series of UK-based epileptic dogs containing 1260 cases from 79 known pedigree breeds and a group of crossbreed dogs.
Article
There is a lack of data on idiopathic epilepsy (IE) in Border Collies (BCs) in the veterinary literature. Genetic epilepsy occurs in BCs and is frequently characterized by a severe clinical course and poor response to medical treatment. Forty-nine BCs diagnosed with IE. Medical records, seizure data, treatment data, and pedigree information of affected dogs were collected. Cases were classified phenotypically as affected or not affected; mild, moderate, or severe clinical course; active epilepsy (AE) or remission; and drug resistant or not drug resistant. Clinical manifestations were classified as having a moderate (33%) or severe clinical course (49%), characterized by a high prevalence of cluster seizures and status epilepticus. Survival time was significantly decreased in dogs < 2 years of age at seizure onset, and in dogs with a severe clinical course. Drug resistance was apparent in 71% of 24 dogs treated with > 2 antiepileptic drugs. The epilepsy remission rate was 18%. Median age at onset was significantly higher and initial seizure frequency was significantly lower in dogs with remission compared with dogs with AE. Pedigree analyses indicated a strong genetic founder effect in the appearance of epilepsy, resembling autosomal recessive inheritance. The present study confirms the occurrence of genetically mediated epilepsy with a frequent severe clinical course and drug resistance in BCs. The results provide information about the long-term prognosis of IE in BCs for veterinarians and concerned owners, and may benefit breeders as well.
Article
To establish the mode of inheritance and describe the clinical features of epilepsy in the Belgian shepherd, taking the outset in an extended Danish dog family (199 individuals) of Groenendael and Tervueren with accumulated epilepsy. Epilepsy positive individuals (living and deceased) were ascertained through a telephone interview using a standardised questionnaire regarding seizure history and phenomenology. Living dogs were invited to a detailed clinical evaluation. Litters more than five years of age, or where epilepsy was present in all offspring before the age of five, were included in the calculations of inheritance. results: Out of 199 family members, 66 dogs suffered from epilepsy. The prevalence of epilepsy in the family was 33%. Fifty-five dogs experienced focal seizures with or without secondary generalisation, while four dogs experienced primary generalised seizures. In seven dogs, seizures could not be classified. The mode of inheritance of epilepsy was simple Mendelian. This study identified that the Belgian shepherd suffers from genetically transmitted focal epilepsy. The seizure phenomenology expressed by family members have a strong resemblance to what has been reported for familial partial (focal) epilepsy in humans with variable foci with suggestion of linkage to chromosome 2 and chromosome 22q12.
Article
Study of the pedigrees of a population of normal and epileptic Alsatians has revealed that there is a genetic basis for the condition in this breed, and that this basis is more complex than has hitherto been suggested. A preponderance of males is affected and there is strong evidence for additive factors determining the age at which animals first show clinical signs, and for the effect of one or more major genes. Only an objective test-mating programme is likely to delineate the true mode of inheritance.
Article
Survey data were collected on the incidence of epileptic seizures in 997 Belgian tervuerens. The heritability of this disorder was estimated as 0.77 (with a 95 per cent confidence interval spanning from 0.65 to 0.88) using a Bayesian analysis in an ordered categorical threshold model. Single locus models do not appear adequate as an explanation for this inherited seizure disorder. The high heritability estimate suggests that breeders can wage a successful battle against this disorder by breeding unaffected individuals, particularly those from families with no history of seizures.
Article
A study was undertaken to define the mode of inheritance of idiopathic epilepsy in Labrador retrievers in Switzerland. Seven hundred and ninety-two pedigree certificates from a population of healthy and epileptic dogs from 11 generations were evaluated. Forty-four different families (giving a total of 55 epileptic dogs) were included. Most patients showed generalised grand mal seizures and the onset was within one to three years in 41 per cent. Males were no more affected than females and the gender ratio between epileptic and control animals was not significantly different (P > 0.05). Additionally, there was no difference in average total inbreeding coefficient between both sexes, or with respect to age of onset of seizures. The increased manifestation of seizures in some subpopulations and the repeated occurrence in different families of the same sires suggested that there was a genetic basis for the condition in the breed. Results of pedigree analyses and from use of the binomial test support the hypothesis of a polygenic, recessive mode of inheritance. However, only an objective test-mating programme is likely to define the exact mode of inheritance.
Article
Large computerized medical databases offer great potential for epidemiological research. However, data-quality issues must be addressed. This study evaluated the agreement between veterinary practice records and computerized insurance data in a large Swedish claims database. For the year 1995, the company insured over 320,000 dogs and cats. A total of 470 hard-copy records were sampled from claims for health care (n = 236) and life insurance (n = 234). Computerized insurance data for these claims were accessed and records from the attending veterinary practices were collected. For health and life claims, respectively, 79.2 and 72.8% of practice records were retrieved. Variables compared between the computer and practice records were breed, sex, date of birth and diagnosis for the claim. The degree of agreement was categorized as agreement, minor disagreement, major disagreement or data missing. Multivariable logistic regression was used to examine factors associated with errors. The observed agreement for breed and sex was excellent. There was 28.9 and 33.8% minor disagreement for the date of birth for health and life claims, respectively. This was mainly because, prior to 1993, the date of birth was coded as the first of January when more complete information was unavailable. Major disagreement (different year of birth) was low for both health and life claims. For health and life claims, the observed agreement for diagnosis was 84.0 and 84.9%, minor disagreement was 6.4 and 4.3%, and major disagreement 5.9 and 9.4%, respectively. Although there was no difference based on size of the veterinary clinic involved, there was a tendency for better agreement between the practice record and the computerized insurance data for claims from clinics with computerized practice records (n = 40) than for clinics with manual practice records (n = 286). Rates of discrepancy were affected by the clerk who processed the claims. Records processed by two of the 21 clerks had significantly more disagreements. Given the nature of the data, it was only possible to calculate a measure of observed agreement. In general, the agreement between data in the insurance-company database and from the practice records was excellent for demographic data such as breed and sex and fair for diagnostic information and date of birth. In general, the data are adequate to support ongoing research with due considerations of certain limitations.
Article
A study was conducted to investigate the clinical aspects and to define the mode of inheritance of idiopathic epilepsy in the Bernese mountain dog. Pedigree analyses were carried out on an open, non-preselected population of 4005 dogs. Five different subpopulations with 50 epileptic dogs from 13 generations were included. Almost all epileptic patients showed generalised seizures of the grand-mal type with a well-defined prodromal and postictal phase. The majority (62 per cent) of the epileptic dogs had had their first seizures at between one and three years of age and it was found that the age at first seizure was significantly (P < 0.05) lower in dogs from affected parental animals than in dogs from healthy parental animals. A clear predisposition for males was also noted. Additionally, there was no correlation between inbreeding coefficient and age at first seizure or incidence rate of seizures. The increased occurrence of the disease in different subpopulations and different families of the same sires or dams showed that there was a genetic basis for the condition in the Bernese mountain dog. Furthermore, the results of the pedigree analyses and binomial test support the hypothesis that idiopathic epilepsy has a polygenic, recessive mode of inheritance in the breed. Additional objective test-mating programmes would however be necessary to define the exact mode of inheritance.
Article
A sample of the Swedish population was surveyed by interviewing households by telephone. The number interviewed was 11,762, of which 15.5% owned dogs, and of these, 77.9% had one dog. The estimated total population of dogs in Sweden was just over 800,000. Dog-owning was more common in more rural areas compared to larger cities. The numbers of male and female dogs were similar and few dogs were neutered. Mean age was 5.7 years with median 5 years. Mongrels comprised 13.3% and the most common breed was the dachshund (7.4%). Of dogs with information on insurance status, 68.4% of the dogs were insured for veterinary care and 58.3% were life insured.
Article
To obtain heritability estimates for diseases and characteristics in Boxers. Birth cohort of 2,929 purebred Boxers from 414 litters. Heritability estimates were determined for cheiloschisis-palatoschisis, cryptorchidism, epilepsy, stifle disorders, cardiac disorders, coat color, birth weight, and adult weight, and height. Binary traits were analyzed by use of a mixed-effects probit model. Some traits also were analyzed by use of a model that postulated monogenic inheritance. Full pedigree analyses were performed. Variation in incidences of disease among clusters of related dogs was evaluated. Heritability estimates were virtually zero for cardiac disorders, medium (0.17 to 0.36) for most other traits, and high (> 0.55) for coat color, birth weight, and adult height. Litter effects and risk factors affected cheiloschisis-palatoschisis, heart murmur, coat color, broadly defined epilepsy, and adult weight. Litter effects may be attributable to common environmental effects for littermates but also may be attributable to dominance variation caused by a recessive gene. Heritability estimates increased when stricter definitions for epilepsy and stifle disorders were used. The monogenic model did not reveal higher heritability estimates for 6 traits analyzed. Incidences for white coat differed significantly for 10 familial clusters, confirming high heritability and effects of familial lineage. Results indicate that genetic improvement of most traits should be feasible, except for cardiac disorders. However, because most traits are influenced by environmental effects as well as genetic effects, genetic counseling based on polygenic inheritance and use of familial information rather than strict exclusion of parents is preferred.
Article
To identify risk factors for episodes of status epilepticus (SE) in dogs with idiopathic epilepsy and determine how SE affects long-term outcome and survival time. Retrospective study. 32 dogs with idiopathic epilepsy. Information on signalment, seizure onset, initiation of treatment, anticonvulsants administered, number of episodes of SE, overall seizure control, and long-term outcome was obtained from medical records and through telephone interviews. Differences between dogs that did and did not have episodes of SE were evaluated statistically. 19 (59%) dogs had 1 or more episodes of SE. Body weight was the only variable significantly different between dogs that did and did not have episodes of SE. Thirteen dogs (9 that did not have episodes of SE and 4 that did) were still alive at the time of the study and were > or = 10 years old. Six of the 19 (32%) dogs that had episodes of SE died of causes directly attributed to the seizure disorder. Mean life spans of dogs that did and did not have episodes of SE were 8.3 and 11.3 years, respectively. Survival time was significantly different between groups. Results suggest that a substantial percentage of dogs with idiopathic epilepsy will have episodes of SE. Dogs with greater body weights were more likely to have episodes of SE, and early appropriate seizure treatment did not appear to decrease the risk that dogs would have episodes. Most dogs with idiopathic epilepsy had an expected life span, but survival time was shorter for dogs that had episodes of SE.
Article
The purpose of this study was to investigate the prevalence and selected risk factors of epilepsy, the proportion of dogs with epilepsy in remission, and the types of seizures in Danish Labrador Retrievers. A prospective cross-sectional study of epilepsy was conducted in 1999-2000. The study was carried out in 2 phases in a reference population consisting of 29,602 individuals. In phase 1, 550 dogs were selected by random sampling stratified by year of birth. A telephone interview was used to identify dogs with possible epilepsy. In phase 2, dogs judged during phase 1 as possibly suffering from epilepsy were further subjected to physical and neurologic examination, CBC, blood chemistry, and a questionnaire on seizure phenomenology. Seventeen dogs were diagnosed with epilepsy, yielding a prevalence of 3.1% (95% CI 1.6-4.6%) in the Danish population of Labrador Retrievers. A diagnosis of epilepsy was 6 times more probable in dogs >4 years (born before 1995) than in younger dogs (born between 1995 and 1999) (P = .004, relative risk = 6.5). No significant difference in risk between genders was observed, nor could any effect of neutering be proven statistically. The frequencies of primary generalized seizures and partial seizures (with or without secondary generalization) were 24 and 70%, respectively. The type of seizures could not be classified in 6%. In conclusion, the 3.1% prevalence of epilepsy in Danish Labrador Retrievers is higher than the 1% prevalence of epilepsy described in the general canine population, establishing that this breed is at increased risk.
Article
Medical record, seizure survey, and telephone interview information was obtained for 29 Vizslas with idiopathic epilepsy (IE), 74 unaffected siblings, and 41 parents to determine the common clinical characteristics and most likely mode of inheritance. IE was diagnosed on the basis of the age of seizure onset, laboratory results, and neurologic examination findings. Computerized tomography (CT) or magnetic resonance imaging (MRI) scan with cerebrospinal fluid (CSF) analysis was required for the inclusion of dogs with an age of seizure onset of < 6 months or > 5 years. Simple segregation analysis was performed with an ascertainment correction and chi-square analysis. IE appeared to be familial in these pedigrees, with 79% of affected Vizslas exhibiting partial onset seizures. Partial seizure signs included a combination of limb tremors, staring, pupillary dilatation, or salivation without loss of consciousness in > 50% of the dogs with partial signs. The estimated segregation frequency of P = .22 (95% CI, P = .08 to .36) was consistent with autosomal recessive inheritance; however, polygenic inheritance could not be excluded as a possibility. Simulated linkage with FASTSLINK estimated that the average logarithm of odds (LOD) score would be 3.23 with a 10-centimorgan (cM) whole-genome scan for these families, indicating that these families would be useful for a whole-genome scan to potentially find the chromosomal segment(s) containing the epilepsy gene or genes. We conclude that IE in Vizslas appears to be primarily a partial onset seizure disorder that may be inherited as an autosomal recessive trait.
Article
To determine clinical characteristics and mode of inheritance of idiopathic epilepsy (IE) in English Springer Spaniels. Original study. 45 dogs with IE and 74 siblings and their respective parents. IE was diagnosed on the basis of age at the time of seizure onset and results of laboratory testing and neurologic examinations. Simple segregation analysis was performed with the Davie method. Median age at the onset of seizures was 3 years; however, 9 (20%) dogs were between 5 and 6 years old at the time of the onset of seizures. Twenty-one dogs (47%) had generalized seizures, and 24 (53%) had focal onset seizures. Results of segregation analysis were consistent with partially penetrant autosomal recessive or polygenic inheritance. Simulated linkage indicated that there was a 58% chance of obtaining suggestive linkage with the available pedigrees. Results of the present study suggest that in English Springer Spaniels, IE segregates in a manner that is consistent with partially penetrant autosomal recessive inheritance (ie, a single major locus with modifying genes) or polygenic inheritance. Given enough families with accurate phenotypic information and available DNA, it should be possible to use genetic linkage analysis to identify chromosomal segments containing the causative gene or genes.
Article
Causes of death and age at death of 2928 dogs are reported from a questionnaire study among members of the Danish Kennel Club (DKC) in 1997. The dogs represented 20 breeds, 15 breed-groups and a group of mixed-breed dogs. The median age at death for all dogs in the study was 10.0 years. Mixed-breed dogs had a higher median age at death (11.0 years) than the entire population, but breeds like Shetland Sheepdog, Poodle and Dachshund exceeded this age (12 years). The Bernese Mountaindog, the group of Molossian types and the Sighthounds had the shortest life span with a median age at death of 7.0 years. Old age was the most frequent reported cause of death (20.8%) followed by cancer (14.5%), behavioural problems (6.4%) accidents (6.1%), hip dysplasia (4.6%), heart diseases (4.6%) and spinal diseases (3.9%). Breed-specific proportional mortalities with 95% confidence limits are given for the six most prevalent specific causes of death.
Article
Epilepsy is a common neurological disorder in both dogs and humans. It is refractory to therapy in approximately one-third of canine patients, and even with the advent of new antiepileptic drugs for humans, appropriate treatment options in dogs remain limited. The pathogenesis and pathophysiology of epilepsy is being studied extensively in both human patients and rodent models of experimental epilepsy at the cellular and molecular level, but very little is known about the aetiologies of epilepsies in dogs. In this review, canine epilepsy will be discussed with reference to the human epilepsies and experimental epilepsy research. There is much work to be done in order to classify canine seizure types and breed-specific epileptic syndromes, particularly with reference to electroencephalographic abnormalities and possible genetic abnormalities. The review considers the appropriate use of antiepileptic drugs: phenobarbitone and potassium bromide are effective in most canine patients, although dosing regimes need to be carefully tailored to the individual, with serum concentration measurement. However, a significant proportion of patients remains refractory to these drugs. Work is currently underway to test the efficacy of newer antiepileptic drugs in the treatment of canine epilepsy, and preliminary data suggest that human drugs such as levetiracetam and gabapentin are of benefit in dogs with refractory epilepsy.
Article
During the last 15 years, breeders have reported an increase in the proportion of Irish Wolfhounds with seizure disorders. Clinical data and pedigrees from closely related Irish Wolfhounds were collected retrospectively and analyzed. Idiopathic epilepsy was diagnosed, by exclusion of other causes for seizures, in 146 (18.3%) of 796 Irish Wolfhounds from 115 litters. The first seizure occurred by the age of 3 years in 73% of all dogs. Males were more commonly affected than females (61.6% versus 38.4%), with males having a later average age of seizure onset. The life expectancy of affected dogs was decreased by 2 years when compared with the average Irish Wolfhound population. The heritability index for the affected dogs, their littermates, and unaffected parents was 0.87. No simple mode of inheritance explains the pattern of affected dogs in pedigrees. Hallmarks of dominant and sex-linked inheritance were notably absent, and the segregation ratio was less than would be expected for simple autosomal recessive inheritance. Assuming all affected dogs have the same form of epilepsy, the simplest description of the complex pattern of inheritance observed is autosomal recessive, with incomplete penetrance and male dogs at increased risk.
Article
Idiopathic childhood epilepsies with benign outcomes are well recognized in human medicine, but are not reported in veterinary literature. We recognized such a neurologic syndrome in Lagotto Romagnolo dogs. Twenty-five Lagotto Romagnolo puppies from 9 different litters examined because of simple or complex focal seizures and 3 adult Lagotto Romagnolo dogs exhibiting similar clinical signs were used. Clinical and diagnostic evaluations of affected dogs were conducted, including electromyography, electroencephalography, and other testing. Seizures in puppies began at 5 to 9 weeks of age and usually resolved spontaneously by 8 to 13 weeks. Those with the most severe seizures also had signs of neurologic disease between these seizures, including generalized ataxia and hypermetria. There were no abnormalities in routine laboratory screenings of blood, urine, and cerebrospinal fluid. Electromyography, brainstem auditory-evoked potentials, and magnetic resonance imaging revealed no specific and consistent abnormalities. Fourteen of 16 (87.5%) affected puppies and 2 of 3 (67%) adult dogs revealed epileptiform activity in the electroencephalogram. Histopathologic examination in 1 puppy and 1 adult dog revealed lesions of Purkinje cell inclusions and vacuolation of their axons restricted to the cerebellum. Pedigree analysis suggests an autosomal recessive mode of inheritance. This disorder, with simple or complex focal seizures and cerebellar lesions, represents a newly recognized epileptic syndrome in dogs.