Mark Robert Keezer

Université de Montréal | UdeM · Neurosciences

Objective: To evaluate the impact of text mining (TM) on the sensitivity and specificity of title and abstract screening strategies for systematic reviews (SR). Study design and setting: Twenty reviewers each evaluated a 500 citation set. We compared five screening methods: conventional double screen (CDS), single screen (SS), double screen with...

Background and objectives: Late-onset epilepsy is a heterogenous entity associated with specific aetiologies and an elevated risk of premature mortality. Specific multimorbid-socioeconomic profiles and their unique prognostic trajectories have not been described. We sought to determine if specific clusters of late onset epilepsy exist, and whether...

Objective: The literature on sudden unexpected death in epilepsy (SUDEP) has been evolving at a staggering rate. We conducted a bibliometric analysis of the SUDEP literature with the aim of presenting its structure, performance, and trends. Methods: The Scopus database was searched in April 2023 for documents explicitly detailing SUDEP in their...

Tuberous sclerosis complex (TSC) is a multisystem disorder caused by loss-of-function mutations in TSC1/2 proteins. This results in constitutive mTOR activation and predisposes to the development of benign tumours, with renal angiomyolipomas (AMLs) and tuber-related drug-resistant epilepsy (DRE) being major causes of morbidity and mortality in adul...

We conducted a scoping review on non-medical cannabis (NMC) use in people with epilepsy (PWE), focusing on their experience, habits, and beliefs regarding NMC. Evidence on NMC use in PWE is sparse and heterogeneous. Lifetime prevalence of NMC use varied from 0.69% to 76.8%. Children and adults took NMC differently. Most PWE perceived NMC as benefic...

Importance: Acute symptomatic seizures occurring within 7 days after ischemic stroke may be associated with an increased mortality and risk of epilepsy. It is unknown whether the type of acute symptomatic seizure influences this risk. Objective: To compare mortality and risk of epilepsy following different types of acute symptomatic seizures. D...

Objective The use of medical cannabis among people with epilepsy (PWE) has been garnering increasing interest. In this scoping review, we aimed to summarize the literature on recreational/non-medical cannabis (NMC) use in PWE, focusing on the experience, habits, and beliefs of PWE regarding NMC.Methods Four databases (OVID Medline, OVID Embase, Ovi...

Introduction The diagnosis of epilepsy frequently relies on the visual interpretation of the electroencephalogram (EEG) by a neurologist. The hallmark of epilepsy on EEG is the interictal epileptiform discharge (IED). This marker lacks sensitivity: it is only captured in a small percentage of 30 min routine EEGs in patients with epilepsy. In the pa...

Objective: There are no clinical guidelines dedicated to the treatment of epilepsy in older adults. We investigated physician opinion and practice regarding the treatment of people with epilepsy aged 65 years or older. We also sought to study how our opinion and practice varied between geriatricians, general neurologists, and epilepsy neurologists...

Rationale Frailty is an important aspect of biological aging, referring to the increased vulnerability of individuals with frailty to physical and psychological stressors. While older adults with epilepsy are an important and distinct clinical group, there are no data on frailty in this population. We hypothesize that frailty will correlate with th...

PURPOSE There is currently no recommended risk of bias (ROB) tools to assess the internal validity of systematic reviews involving exposure or frequency studies. We aimed to first identify and secondly compare the inter-rater reliability (IRR) of six commonly used tools for frequency (Loney scale, Gyorkos checklist, American Academy of Neurology [A...

Background and objectives: There is a paucity of data on the frequency and prognosis of infratentorial brain injury among patients suspected of death by neurologic criteria (DNC), which likely contributes to scientific uncertainty regarding the role of isolated brainstem death in DNC determination. Our aim was to synthesize the prevalence, charact...

Background The diagnosis of epilepsy frequently relies on the visual interpretation of the electroencephalogram (EEG) by a neurologist. The hallmark of epilepsy on EEG is the interictal epileptiform discharge (IED). This marker lacks sensitivity: it is only captured in a small percentage of 30-minute routine EEGs in patients with epilepsy. In the p...

Background: Ischemic stroke (IS) may be the first sign of an occult cancer, due to an underlying paraneoplastic prothrombotic state. Predictors of occult cancer in acute IS, however, remain unclear. We performed a single-center study to identify clinical features that may distinguish cancer-associated IS from IS without recent cancer. Methods: We r...

Background: People with acute ischemic stroke (IS) have a higher prevalence of occult malignancy. Consensus is lacking, however, on the extent of cancer screening tests that should be offered in this population. We performed a single-center study to review curent cancer screening practices in acute IS. Methods: We reviewed consecutive admissions fo...

Objective Our study describes adults in Canada between 2009 and 2013 receiving at least one antiseizure medication (ASM) at the end of a hospitalization for newly-diagnosed epilepsy, with a focus on the type of ASM prescribed, changes in drug prescriptions after one year, and how this differs between younger and older adults. Methods Canada-wide d...

Objective A recent FDA warning concerning an arrhythmogenic potential of lamotrigine created concern in the neurological community. This warning was based on in vitro studies, but no clinically relevant risk was considered. This rapid systematic review aims to elucidate the risk of lamotrigine on sudden death or electrocardiogram abnormalities. Me...

Objective: Summarize the current evidence on efficacy and tolerability of vagus nerve stimulation (VNS), responsive neurostimulation (RNS), and deep brain stimulation (DBS) through a systematic review and meta-analysis. Methods: We followed the PRISMA reporting standards and searched Ovid Medline, Ovid Embase, and the Cochrane Central Register o...

Objective: We aimed to assess the reliability and validity of single-item global ratings (GR) of satisfaction with epilepsy surgery. Methods: We recruited 240 patients from four centers in Canada and Sweden who underwent epilepsy surgery ≥1 year earlier. Participants completed a validated questionnaire on satisfaction with epilepsy surgery (the...

Objectives There are few data on adults living with tuberous sclerosis complex (TSC), with most studies focusing on pediatric populations. The objective of our study was to examine a large national cohort of adults with TSC, and to describe the clinical characteristics of these adults and the nature of the multidisciplinary care that they receive....

Frailty is often described as being an increased vulnerability to the effects of stressors. There is little research investing how frailty may act as either a mediator or participate in interactions in the associations between risk factors and chronic disease. We will present novel analyses of the Canadian Longitudinal Study on Aging, focusing on t...

Acute Central Nervous System (CNS) Graft Versus Host Disease (GvHD) is a rare form of GvHD, only described in case reports. Knowledge about this condition is extrapolated from chronic CNS GvHD cases occurring mostly after hematopoietic stem cell transplantation. GvHD following solid organ transplantation is an unexpected complication. GvHD after li...

Background Not all research findings are translated to clinical practice. Reasons for lack of applicability are varied, and multiple frameworks and criteria exist to appraise the general applicability of epidemiological and clinical research. In this two-part study, we identify, map, and synthesize frameworks and criteria; we develop a framework to...

Background: We aimed to evaluate heart rate variability (HRV) changes in insulo-opercular epilepsy (IOE) and after insulo-opercular surgery. Methods: We analyzed 5-min resting HRV of IOE patients before and after surgery. Patients' SUDEP-7 risk inventory scores were also calculated. Results were compared with age- and sex-matched patients with t...

Background: Drug-resistant epilepsy (DRE) can affect up to one third of individuals with epilepsy. We conducted a systematic review and meta-analysis of vagus nerve stimulation (VNS), responsive neurostimulation (RNS), and deep brain stimulation (DBS) in patients with DRE to summarize the current evidence on efficacy and tolerability for these neur...

Importance Enzyme-inducing antiseizure medications (eiASMs) have been hypothesized to be associated with long-term risks of cardiovascular disease. Objective To quantify and model the putative hazard of cardiovascular disease secondary to eiASM use. Design, Setting, and Participants This cohort study covered January 1990 to March 2019 (median [IQ...

Research on frailty has expanded in the last decade, but direct evidence supporting its implementation in clinical practice may be limited. This mapping review synthesizes the contexts-of-use and overall clinical applicability of recent pre-COVID frailty research. We sampled 476 articles from articles published on frailty in PubMed and EMBASE in 20...

Purpose: Indocyanine green fluorescence angiography (ICG-FA) is a validated non-invasive imaging technique used to assess tissue vascularization and guide intraoperative decisions in many surgical fields including plastic surgery, neurosurgery, and general surgery. While this technology is well-established in adult surgery, it remains sparsely used...

Objective To identify risk factors for acute symptomatic seizures and post-stroke epilepsy after acute ischemic stroke and evaluate the effects of reperfusion treatment. Methods We assessed the risk factors for post-stroke seizures using logistic or Cox regression in a multicenter study including adults from eight European referral centers with ne...

Objective This study was undertaken to investigate the distribution of social, lifestyle/behavior, and chronic disease risk factors for cardiovascular disease (CVD) in people with epilepsy as compared to the general population. We also measured the cross-sectional association between epilepsy and CVD in older adults, with and without adjustments fo...

Objective The 19-item Epilepsy Surgery Satisfaction Questionnaire (ESSQ-19) is a validated and reliable post hoc means of assessing patient satisfaction with epilepsy surgery. Prediction models building on these data can be used to counsel patients. Methods The ESSQ-19 was derived and validated on 229 patients recruited from Canada and Sweden. We...

Epidemiological estimates indicate that individuals with epilepsy are more likely to experience headaches, including migraine, than individuals without epilepsy. Headaches can be temporally unrelated to seizures, or can occur before, during or after an episode; seizures and migraine attacks are mostly not temporally linked. The pathophysiological l...

Objective Ictal semiology interpretation for differentiating psychogenic nonepileptic seizures (PNESs) and epileptic seizures (ESs) is important for the institution of appropriate treatment. Our objective was to assess the ability of different health care professionals (HCPs) or students to distinguish PNES from ES based on video-recorded seizure s...

Background Deficit-accumulation frailty indices (FIs) are widely used to characterize frailty. FIs vary in number and composition of items; the impact of this variation on reliability and clinical applicability is unknown. Methods We simulated 12,000 studies using a set of 70 candidate deficits in 12,080 community-dwelling participants 65 years an...

This protocol for a Cochrane Review is out of date and has been withdrawn in order to adhere to Cochrane policy. The editorial group responsible for this previously published document have withdrawn it from publication.

Background Prehospital delays are a major obstacle to timely reperfusion therapy in acute ischemic stroke. Stroke sign recognition, however, remains poor in the community. We present an analysis of repeated surveys to assess the impact of Face, Arm, Speech, Time (FAST) public awareness campaigns on stroke knowledge. Methods Four cross-sectional su...

Objective: Although the prevalence of comorbid epilepsy and dementia is expected to increase, the impact is not well understood. Our objectives were to examine risk factors associated with incident dementia and the impact of frailty and dementia on mortality in older adults with epilepsy. Methods: The CALIBER scientific platform was used. People...

Background: Stroke survivors may be at higher risk of incident cancer, although the magnitude and the period at risk remain unclear. We conducted a retrospective cohort study to compare the risk of cancer in stroke survivors to that of the general population. Methods: The Canadian Longitudinal Study on Aging is a large population-based cohort of...

Objective In order to evaluate the incidence and prevalence of drug-resistant epilepsy (DRE) as well as its predictors and correlates, we conducted a systematic review and meta-analysis of observational studies. Methods Our protocol was registered with PROSPERO and the PRISMA and MOOSE reporting standards were followed. We searched MEDLINE, Embase...

Background: Cancer promotes thromboembolism through inflammation and hypercoagulability, and an ischemic stroke may be the first sign of an occult malignancy. Stroke survivors may be at higher risk of incident cancer diagnosis, although the magnitude and the period at risk remain unclear. We conducted a retrospective cohort study to compare the ris...

The International League Against Epilepsy (ILAE) / American Epilepsy Society (AES) Task Force on the cardiac effects of lamotrigine was convened in response to a recent addition to the lamotrigine label by the US Food and Drug Administration (FDA).1 Lamotrigine is the nonproprietary name for a medicine that is sold under its generic name and severa...

Background: Intervention time in response to seizures (IT) and adverse events (AE) have emerged as key elements in epilepsy monitoring unit (EMU) management. We performed an audit of our EMU, focusing on IT and AEs. Methods: We performed a retrospective study on all clinical seizures of admissions over a one year period at our Canadian academic te...

Background The optimal approach for cancer screening after an ischemic stroke remains unclear. Aims We sought to summarize the existing evidence regarding the frequency and predictors of cancer after an ischemic stroke. Summary of review We searched seven databases from January 1980 to September 2019 for articles reporting malignant tumors and my...

Background A widely held dictum in aging research is that heterogeneity in health increases with age, but the basis for this claim has not been fully investigated. We examined heterogeneity at different ages across health characteristics to describe variation and trends; we investigated the comparative importance of between‐age versus within‐age he...

Objective: Adult drug-resistant epilepsy (DRE) is associated with significant morbidity. Infiltration of immune cells is observed in DRE epileptic foci; however, the relation between DRE and the peripheral immune cell compartment remains only partially understood. We aimed to investigate differences in immune cell populations, cytokines, and neuro...

Objective A web-based intervention was developed to support epilepsy self-management. A mixed methods study was undertaken to evaluate the intervention’s extent of utilization, acceptability and preliminary effects, and to assess user perception of it. Methods First, a pilot parallel-group randomized controlled trial was conducted with a convenien...

Objective No validated tools exist to assess satisfaction with epilepsy surgery. We aimed to develop and validate a new measure of patient satisfaction with epilepsy surgery, the 19‐item Epilepsy Surgery Satisfaction Questionnaire (ESSQ‐19). Methods An initial 31‐item measure was developed based on literature review, patient focus groups, thematic...

Background The benefit of acute carotid stenting compared with no acute stenting on clinical outcomes among patients with tandem lesions (TL) undergoing endovascular thrombectomy (EVT) remains unknown. Methods We conducted a a systematic review and meta-analysis of studies comparing acute carotid stenting versus no stenting among TL patients under...

Vagus nerve stimulation (VNS) is often used for patients with drug‐resistant epilepsy. Although this intervention may improve seizure control and mood, a number of factors must be considered when patients with VNS near end of life. We reviewed relevant literature to create a proposed guideline for management of patients with VNS in palliative care...

Background Recent progress in multiple sclerosis (MS) management has contributed to a greater life expectancy in persons with MS. Ageing with MS comes with unique challenges and bears the potential to greatly affect quality of life and socioeconomic burden. Objectives To compare frailty in ageing persons with multiple sclerosis (pwMS) and controls...

Rioux B, Touma L, Nehme A, Gore G, Keezer MR, Gioia LC (2020). Frequency and Predictors of Occult Cancer in Ischemic Stroke: A Systematic Review/Meta-Analysis. e-Poster presentation. 2020 American Academy of Neurology Annual Meeting, Toronto CA (accepted, e-poster disseminated on the 2020 AAN Science Highlights Virtual Platform; in-person conferenc...

Rioux B, Keezer MR, Gioia LC. (2020). Case report: Diagnosis of Occult Cancer in Acute Ischemic Stroke Using Positron Emission Tomography Combined with Computed Tomography. e-Poster presentation. 2020 American Academy of Neurology Annual Meeting, Toronto CA (accepted, e-poster disseminated on the 2020 AAN Science Highlights Virtual Platform; in-per...

Background Anecdotal cases of exophthalmos after acute mechanical thrombectomy have been described. We sought to estimate the incidence in a large cohort of patients with acute anterior circulation stroke treated with mechanical thrombectomy. Secondarily, we aimed to evaluate the underlying mechanism and to differentiate it on imaging from other pa...

Background: The optimal initial diagnostic approach to suspected occult cancer as a cause following an acute ischemic stroke (AIS) of undetermined origin remains unknown. Positron emission tomography combined with computed tomography (PET/CT) may play a role as the initial imaging modality in cases of suspected occult cancer. Results: A 77-year-ol...

Background: Despite the growing interest for cancer-associated strokes and suggestions of diagnostic approaches to occult cancer in patients with IS, the frequency and predictors of cancer after an IS remain unclear. Design/Methods: We searched eight electronic databases (including MEDLINE and EMBASE) in all languages from January 1980 to February...

Objectives We aimed to develop and internally validate a measure of multimorbidity burden using data from the Canadian Longitudinal Study on Aging (CLSA). Design Data from 40 264 CLSA participants (52% men) aged 45–85 years (a mean of 63 years) were analysed. We used logistic regression models to predict overnight hospitalisation in the last 12 mo...

Hyperammonemic encephalopathy (HE) is a metabolic condition precipitated by elevated blood ammonia, which may be idiopathic or secondary to increased production (e.g., infection with urease-positive bacteria) or decreased elimination of ammonia (e.g., liver failure), or drug-induced (e.g., valproic acid).

Elderly individuals (aged at least 60 or 65 years) represent a rapidly growing segment of the population. The incidence and prevalence of epilepsy is higher in this age group than in any other. Diagnosing epilepsy in the elderly can be challenging because the causes and clinical manifestations of seizures often differ as compared with younger indiv...

Rioux B, Touma L, Nehme A, Gore G, Keezer MR, Gioia LC (2019). Frequency and predictors of occult cancer in ischemic stroke: a systematic review and meta-analysis. Poster presentation. 19th Congress of the Quebec Vascular Sciences Society, Quebec QC.

In Canada, recreational use of cannabis was legalized in October 2018. This policy change along with recent publications evaluating the efficacy of cannabis for the medical treatment of epilepsy and media awareness about its use have increased the public interest about this agent. The Canadian League Against Epilepsy Medical Therapeutics Committee,...

Pseudo-chemical meningitis and the malignant transformation of an epidermoid cyst - Stanislas Demuth, David E. Lasry, Sami Obaid, Laurent Letourneau-Guillon, Michaël Chassé, Karl Bélanger, France Berthelet, Michel W. Bojanowski, Mark R. Keezer

Objective To evaluate the efficacy and tolerability of antiepileptic drugs (AEDs) in elderly individuals with epilepsy. Methods We searched four electronic databases as well as bibliographies and conference abstracts. Published and unpublished, randomized, or quasirandomized trials reporting the use of AEDs in people aged at least 60 years with ep...

Epilepsy is a chronic neuronal disorder affecting ~65 millions people throughout the world. 1/3 of patients suffer from drug-resistant epilepsy (DRE). Objective to assess the relationship between different Th17 markers and the clinical course of epilepsy to uncover new potential immune biomarkers and therapeutic targets of interest for DRE. Appro...

Background: Botulism is an acute paralytic illness caused by a neurotoxin produced by Clostridium botulinum. Supportive care, including intensive care, is key, but the role of other medical treatments is unclear. This is an update of a review first published in 2011. Objectives: To assess the effects of medical treatments on mortality, duration...

Background: Epilepsy surgery is an important treatment option for people with drug-resistant epilepsy. Surgical procedures for epilepsy are underutilized worldwide, but it is far worse in low- and middle-income countries (LMIC), and it is less clear as to what extent people with drug-resistant epilepsy receive such treatment at all. Here, we revie...

Contexte et objectifs Des cas anecdotiques d’exophtalmie après thrombectomie mécanique aiguë (MT) ont été décrits. Avec cette étude, nous avons cherché à estimer l’incidence dans une large cohorte de patients ayant subi un AVC aigu de la circulation antérieure traité par MT. Deuxièmement, nous avons cherché à évaluer le mécanisme sous-jacent à ce p...

People with epilepsy often present with comorbid endocrine disorders. Such conditions may affect the clinical manifestations and influence the management of epilepsy. The therapies used in epilepsy can also disrupt endocrine homeostasis and lead to glycemic and hormonal changes with important clinical consequences. Knowing how to recognize and hand...

Objective: To assess sociodemographic, socioeconomic, and clinical correlates of idiopathic REM sleep behavior disorder (RBD) in a 30,097-person national cohort. Methods: Participants 45 to 85 years of age in Canada were collected as part of the Canadian Longitudinal Study on Aging. Possible RBD (pRBD) was screened with the REM Sleep Behavior Di...

Background Our objective was to study the association between the presence of a neurological disease and the comorbidity burden, as well as healthcare utilization. Methods Using baseline data from the Canadian Longitudinal Study on Aging (CLSA), we examined the burden of five neurological conditions. The CLSA is a population‐based study of approxi...

Background Epilepsy surgery is likely underutilised. Our goal was to study the utilisation of epilepsy surgery in the general population, using Canada as a model of a high-income country with universal medical coverage. Methods We systematically identified all epilepsy surgery centres in Canada that were active in 2015. A standardised questionnair...

Background: We conducted a systematic review to ascertain the overall mortality and causes of premature mortality in epilepsy. Methodology: We searched PubMed and Embase to identify relevant articles reporting mortality in epilepsy. An assessment of the methodological quality and overall quality of evidence of the identified studies was done usi...

Background Our aim was to study the quality of the literature search strategies used in recent systematic reviews, and to develop and assess the diagnostic accuracy of six new search strategies (i.e. hedges). Methods We studied six neurological conditions: migraine, stroke, dementia, epileptic seizures, Parkinson's disease, and multiple sclerosis....

Background: Stroke is one of the leading causes of acquired epilepsy in adults. An instrument to predict whether people are at high risk of developing post-stroke seizures is not available. We aimed to develop and validate a prognostic model of late (>7 days) seizures after ischaemic stroke. Methods: In this multivariable prediction model develo...

The basic pathophysiology of epilepsy is still not fully understood. Epidemiological evidence for epilepsy seems to suggest that it may not only be the propensity for seizures to occur. The high prevalence of comorbidity and the finding that premature mortality is still increased in those who are in long-term remission, suggest that there is a syst...

Background: A well-constructed search strategy is an important feature of any systematic review. We aimed to design and validate electronic database (e.g. Pubmed) search strategies (i.e. a hedge or series of words used to identify articles of interest) for six neurological conditions. Methods: We enumerated 10311 consecutive articles in the 21 high...

Background: More timely administration of tissue plasminogen activator (alteplase) for patients with acute ischemic stroke yields greater clinical benefits. We implemented door-to-needle (DTN) time reduction strategies at our center and evaluated their short- and long-term effects on in-hospital treatment delays and clinical outcomes. Methods: S...