Sleep Medicine

Narcolepsy is a sleep disorder with a genetic association with the haplotype DRB1*1501, DQA1*0102, DQB1*0602. This haplotype has been described in different ethnic groups suffering from narcolepsy (Japanese, Caucasian, African Americans, Jews). In a recent study we have found the haplotype DRB1*1502, DQB1*0601, DQA1*0103 in three patients with hypersomnolence. The similarity of this haplotype to the narcoleptic haplotype DRB1*1501, DQB1*0602 and DQA1*0102 has raised the question of whether this haplotype is a marker for sleepiness, or rather indicates a variant of non-cataplectic narcolepsy. This study was conducted to further investigate this question. HLA-DNA analysis was carried out in 20 healthy Jewish patients (age 23.9+/-6.3 years; 13 Ashkenazi, seven non-Ashkenazi) who had objective measures of hypersomnolence. All underwent whole-night polysomnography, multiple sleep latency test and tissue typing. HLA-DNA analysis revealed HLA-DR2 in eight patients of whom five (25%) carried the haplotype DRB1*1502, DQB1*0601, DQA1*0103 (vs. 1.4% in the Israeli population, P<0.0001). Six patients were diagnosed as non-cataplectic narcoleptics. Five of them carried the haplotype DRB1*1502, DQB1*0601, DQA1*0103. Forty percent of the patients carried the haplotype DRB1*04, DQB1*0302, which was not statistically different from its prevalence in the healthy Israeli population (25%). This is the first report describing the haplotype DRB1*1502, DQB1*0601, DQA1*0103 in narcoleptic patients (non-cataplectic). This haplotype is close but different from the already known narcoleptic haplotype DRB1*1501, DQA1*0102, DQB1*0602. We assume that this haplotype represents a variant of non-cataplectic narcolepsy rather than association with hypersomnolence. However, in order to conclude whether this haplotype is a marker for the lack of cataplexy, or represents a variant of non-cataplectic narcolepsy, a larger group of patients should be investigated.

We aimed to evaluate the efficacy of the selective H3 receptor inverse agonist MK-0249 to treat excessive daytime sleepiness (EDS). In this three-period, double-blind, crossover study, 125 patients (100 men, 25 women; mean age, 48.6years) with obstructive sleep apnea receiving nasal continuous positive airway pressure therapy who had refractory EDS were randomized to 2weeks each of daily MK-0249 (5, 8, 10, or 12mg, adaptively assigned), modafinil 200mg, and placebo. At baseline and after each treatment period, six maintenance of wakefulness tests (MWT) and Psychomotor Vigilance Tasks (PVT) were conducted at 2-h intervals, beginning 1h postdose (∼09:00). The Epworth sleepiness scale (ESS), Clinical Global Impression of Severity (CGIS) and Digit Symbol Substitution Test (DSST) also were assessed. The primary end point was MWT sleep latency averaged over the first four time points (MWT-early). MWT-early mean change from baseline sleep latency at week 2 was 1.2min for placebo, 2.1min for MK-0249 (top two doses pooled; P>.05 vs placebo), and 5.9min for modafinil (P⩽.001 vs placebo). MK-0249 showed improvements vs placebo on secondary and exploratory end points of ESS, CGIS, PVT, and DSST. Insomnia adverse events (AEs) were greater for MK-0249 (combined doses, 17.5%) than for placebo (0.9%) or modafinil (1.8%). MK-0249 did not significantly affect MWT sleep latency. However, the pattern of improvement on subjective ratings and psychomotor performance end points suggested that MK-0249 was associated with changes in aspects of cognition and performance not captured by the MWT.

Background: Narcolepsy, a neurological disorder characterized by excessive daytime sleepiness and abnormal REM sleep, is known to be tightly associated with the human leukocyte antigen (HLA) DQB1*0602.Methods: In this study, baseline data collected for a large clinical trial involving 504 narcolepsy patients were used to compare clinical and polysomnographic features of narcolepsy patients with and without HLA-DQB1*0602. Comparisons were adjusted for possible confounding factors and linear regression modeling was used to extract the best predictors for DQB1*0602 positivity.Results: As previously reported, cataplexy was the best clinical predictor for DQB1*0602 positivity. At the polysomnographic level, subjects with DQB1*0602 were found to have a significantly more disrupted nocturnal sleep, a much shorter nocturnal rapid eye movement (REM) sleep latency and more multiple sleep latency test abnormalities (increased number of sleep onset REM periods and decreased mean sleep latency). We also found that subjects with DQB1*0602 had a much higher incidence of periodic limb movements during sleep, confirming the notion that this symptom is genuinely associated with the narcolepsy phenotype.Conclusions: These results support the notion that HLA-DQB1*0602-positive narcolepsy patients are more etiologically homogenous than HLA-DQB1*0602-negative narcoleptic patients.

The aim of the present study was to assess sleep patterns in the adult population of the city of Campinas (Brazil) according to socioeconomic/demographic variables, chronic diseases, and symptoms. A population-based cross-sectional study was conducted using data from the Campinas Health Survey (ISACAMP) carried out in 2008 and 2009. A total of 2637 individuals aged 18 years or older (obtained from a probabilistic sample) were analyzed. Associations between sleep pattern and the independent variables were determined using the chi-square test. Multinomial logistic regression models were used to adjust for confounders. The prevalence of six or fewer hours of sleep was greater among individuals aged 40 years or older and among divorced or single individuals. The sleep pattern of nine or more hours was more prevalent among those with less than 40 years of age, among those who were divorced, or single, among those with a lower level of schooling, those who did not work and housewives. Both short and long sleep patterns were more prevalent among individuals with heart disease, vascular problems, rheumatism/arthritis/arthrosis, osteoporosis, or emotional problems. The prevalence of the short sleep duration was greater among individuals with back problems and those with three or more health conditions. A strong association was found between sleep duration and sleep quality. Socio-demographic factors and health diseases were associated to sleep duration. This issue should be considered in health promotion strategies.

Increasing evidence suggests an association between short sleep with adverse health outcomes: obesity, type 2 diabetes and hypertension. But there are few or no data on "who these short sleepers are" in the general population. To describe short sleepers and the associated sleep disorders in young adults. Cross-sectional telephone survey in a representative sample of 1004 French young adults (25-45 years old). Total sleep time (TST), insomnia, snoring, sleepiness and daytime consequences were assessed using subjective validated tools. Short sleepers were defined as sleeping <6h a weekday (sleep+nap+pauses). Sleep debt was defined as those who "sleep 90 min less than the sleep they need to be in good shape." Prevalence of short sleep was 18%, insomnia 12%, and sleep debt 20% in the total group. Among short sleepers, 16% had insomnia, 45% sleep debt, and 39% neither. Short sleepers were significantly mostly males, blue collar workers and more overweight and obese compared to nonshort sleepers. Working >10h per day, smoking and drinking coffee after 5p.m. were also significantly associated with short sleep. Short sleepers had higher Epworth sleepiness scale ESS scores (7.8 vs 6.7; p = 0.0058) and more sleepiness while driving (11.5% vs 2.9%; p < 0.0001). Short sleep is highly prevalent in young adults but is not an homogeneous group, including both insomniacs and subjects with or without sleep debt. Short sleep has to be defined more precisely in order to better understand its impact on public health.

Despite the fact that narcolepsy is a chronic disorder affecting younger people, there is insufficient information about its societal burden, time course, and familiar effect. We aimed to estimate the factual direct and indirect costs of narcolepsy patients and their families in a national sample using a controlled study design. Using records from the Danish National Patient Registry (1997-2009), all 816 narcolepsy patients and their partners were identified and compared with 3254 randomly chosen controls matched for age, gender, geographic area, and civil status. Direct and indirect costs, including frequencies of primary and secondary sector contacts' and procedures, medication, labor supply, and social transfer payments were extracted from the national databases. Fewer patients (46.7%) than controls (51.4%) were married or cohabiting. Patients with narcolepsy had significantly higher rates of health-related contact, medication use, and a higher socioeconomic cost. Furthermore, they had lower employment rates, and those in employment had a lower income level than control subjects. Partners presented higher public health insurance and public transfers and lower income from employment. In all, the annual mean excess health-related cost, including social transfers, was €9572 for patients with narcolepsy and €3606 for their partners (both p<0.001). Patient consequences could be identified up to 11 years before first diagnosis and became more pronounced as the disease advanced. Narcolepsy causes socioeconomic consequences, not only for patients, but also for their partners, which is present years prior to disease diagnosis, confirming a diagnostic delay.

Since its original description, idiopathic RBD has become a well-established risk factor for neurodegenerative disease. Studies from sleep centers have found that at least 40-65% of patients with idiopathic RBD will develop a defined neurodegenerative phenotype over 10years. This elevated risk of neurodegeneration has been recently confirmed in a population-based study of probable RBD. When a defined syndrome develops, it is almost always a 'synucleinopathy' (Parkinson's disease, Dementia with Lewy Bodies or multiple system atrophy). Often, manifestations of parkinsonism and cognitive impairment overlap. The ability of RBD to predict disease has major implications for development of neuroprotective therapy. First, RBD is a prodromal marker with a disease risk sufficiently high for design of neuroprotective trials. Second, study of idiopathic RBD allows prospective testing of other predictive markers of neurodegeneration. Third, it allows an unprecedented direct examination of the evolution of prodromal disease into defined neurodegenerative syndromes. This review summarizes what is known about the risk of neurodegeneration in idiopathic RBD, the utility of prodromal/predictive markers in synuclein-mediated neurodegeneration, and the evolution of motor and non-motor markers in prodromal stages.

To obtain normative sleep architecture data from unattended home polysomnography in Caucasian and Hispanic children aged 6-11 years. Unattended home polysomnography was performed on a single night in Caucasian and Hispanic children aged 6-11 years as part of the Tucson Children's Assessment of Sleep Apnea Study (TuCASA), a cohort study designed to examine the prevalence and correlates of sleep disordered breathing. A subset of 42 children enrolled in TuCASA who had no symptoms of any sleep disorder and had polysomnograms without technical recording problems. Sleep architecture in preadolescent Caucasian and Hispanic children was not different between boys and girls. However, total sleep time (TST), sleep efficiency (SLE) and time spent in REM sleep declined with increasing age. In addition, the number of sleep to wake stage shifts was slightly higher in younger children. Hispanic children had less Stage 3/4 sleep (18+/-1 vs. 22+/-1%, P</=0.02) and correspondingly more Stage 2 sleep (55+/-2 vs. 50.0+/-1%, P</=0.02) than their Caucasian counterparts. Using unattended home polysomnography, indices of sleep duration and architecture are not different between preadolescent boys and girls. However, with increasing age, TST and SLE decreased. In addition, there are differences in sleep architecture between Caucasians and Hispanics, which may be an important consideration in the evaluation of children with sleep disorders.

An 11-year-old girl was referred for an irresistible urge to move her legs associated with uncomfortable sensations. She was diagnosed with definite Restless Legs Syndrome (RLS) according to 2003 NIH criteria. The IRLSSG severity scale score was 31 (very severe). The girl also presented with dysthymic disorder according to DSM-IV criteria, as confirmed by the semi-structured interview Kiddie-SADS-PL. The score on the Children Depression Inventory (CDI) was in the clinical range (21). The total score on the Sleep Disturbance Scale for Children (SDSC) was 100. A standard PSG revealed a periodic limb movement index of 16.5, indicating that the child also presented with Periodic Limb Movements Disorder. The girl was treated with ropinirole (a D2/D3 dopamine agonist). After 3 months of treatment (0.50mg/day at 8.00 PM), RLS, as well as depressive symptoms, remarkably improved, as suggested by the improvement in the IRLSSG severity and CDI scores (14 and 4, respectively). No side effects were reported. The total score on the SDSC also improved (73). The PLM index did not remarkably change. We strongly recommend double blind, randomized, controlled studies to gain insight into the effective treatment strategies for RLS and depression when they coexist in children.

Although the positive clinical benefits of levodopa have fostered the concept of an abnormality in the dopaminergic system in Restless Legs Syndrome (RLS), research into the nigro-striatal (PET/SPECT studies) or tubero-infundibular (i.e., prolactin secretion) dopaminergic pathways has shown limited positive results. Some research groups have focused on the A11 dopaminergic system in the hypothalamus as this is the primary source of descending dopaminergic input into the spinal cord, an area of the nervous system believed by some investigators to be involved in RLS symptom development. Some investigators have now proposed lesioning or toxin-inhibiting the A11 system as a model of RLS, even though there has been no clear clinical or autopsy data to suggest that RLS is a neurodegenerative disorder. In this study, the A11 cell bodies were identified in 6 RLS and 6 aged-matched control autopsy cases. Cells were stained for tyrosine hydroxylase (TH), and stereological measure of the individual TH (+) cell volume was made. Regional assessment of gliosis as assessed by immunostaining for glial fibrillary acidic protein (GFAP) was made in the surrounding tissue. General histological staining was also performed on the tissue. This study found no significant difference between RLS or control cases on any measure used: TH (+) cell volume, fractional GFAP staining, or general histological examination. Nor was there histological indication of any significant inflammation or concurrent ongoing pathology in these RLS cases. The findings do not support the concept of dramatic cell loss or of a neurodegenerative process in the A11 hypothalamic region of patients with RLS. However, that does not exclude the possibility that the A11 system is involved in RLS symptoms. Changes at the cellular level in dopaminergic metabolism or at the distal synapse with changes in receptors or transporters were not evaluated in this study.

Obstructive sleep apnea (OSA) is a prevalent disorder with multiple consequences including negative effects on neurocognitive function. Several domains of cognitive function are impaired in OSA patients, but the mechanisms through which this sleep disorder results in impairment are not clear. Given the well-known effects of cortisol on cognitive function, in particular memory, the dysregulating effects of OSA on cortisol levels are hypothesized as a potential pathway leading to cognitive impairment. Fifty-five participants with OSA (mean apnea-hypopnea index [AHI], 30.3) were assessed over 2days. Over a 24-h period, blood samples were collected every 2h to examine cortisol levels. The following night, sleep was monitored with polysomnography (PSG). Participants were given a battery of neurocognitive tests, which assessed seven cognitive domains. OSA severity assessed by oxygen desaturation index (ODI) was associated with 24-h cortisol levels. AHI, ODI, and nighttime cortisol levels were associated with global deficit scores (GDS) in cognitive functioning, particularly in domains of learning, memory, and working memory (P<.05 for all). Hierarchical linear regression analysis revealed that nighttime cortisol accounted for 9-16% of variance in learning (P=.018), memory (P=.003), and working memory (P=.016) domains, though apnea severity did not significantly predict any additional variance. In our sample of patients with OSA, nocturnal cortisol levels were associated with neuropsychologic functioning above and beyond the influence of covariates and apnea severity. These findings suggest that OSA-related alterations in cortisol activity may partially explain the pathophysiology of neuropsychologic impairments in sleep apnea.

We investigated cardiac (123)I-metaiodobenzylguanidine (MIBG) scintigraphic assessment as a supportive diagnostic indicator for idiopathic REM sleep behavior disorder (RBD) complicated by moderate to severe obstructive sleep apnea (OSA). (123)I-MIBG was intravenously injected in 23 idiopathic RBD patients with AHI < 5/h, 9 idiopathic RBD patients with 5 <or= AHI < 15/h, 15 idiopathic RBD patients complicated with moderate to severe OSA with AHI >or= 15/h, and 16 moderate to severe obstructive sleep apnea syndrome (OSAS) patients without RBD by polysomnography. Cardiac MIBG uptake based on H/M was significantly decreased in RBD patients with or without OSA compared with patients with moderate to severe OSAS without RBD. ROC analysis revealed that a delayed H/M cut-off value of 1.97 was useful for differentiating idiopathic RBD complicated by moderate to severe OSA from moderate to severe OSAS without RBD. (123)I-MIBG cardiac scintigraphy has the potential to distinguish true RBD from pseudo-RBD associated with OSA. These results are noteworthy because treatment options and follow-up protocols are determined based on evaluation of moderate to severe OSA complicated with RBD, such as overlapping primary sleep disorders.

Although decrease in myocardial iodine-123 metaiodobenzylguanidine ((123)I-MIBG) radioactivity has been reported in patients with rapid eye movement (REM) sleep behavior disorder (RBD), its pathophysiology has not been thoroughly disclosed. We report two RBD patients with differing clinical progression, in whom myocardial (123)I-MIBG scintigraphy was performed. One 69-year-old patient had more than a 20-year history of idiopathic RBD and showed a decrease in myocardial (123)I-MIBG radioactivity. The other 69-year-old patient started to manifest nocturnal behaviors at age 62, then mild parkinsonism at age 68, and showed a similar decrease in myocardial (123)I-MIBG radioactivity both before and after the onset of parkinsonism. These cases suggest that RBD could develop in diverse patterns of clinical progression even if signs of underlying Lewy body pathology are uniformly indicated.

The purpose of this study was to detect the eventual presence of a minor voluntary motor involvement in restless legs syndrome (RLS), not detectable clinically, which might be observed by means of a sophisticated instrumental analysis of movement, such as gait analysis. Gait analysis was performed and surface EMG activity was recorded in 13 RLS patients and 8 normal controls from 8 muscles: tibialis anterior, gastrocnemius lateralis, gastrocnemius medialis, and soleus in both legs. Ten out of the 13 RLS patients and none of the normal control group showed a mild abnormality of the EMG activation of the gastrocnemius muscles during gait which, however, had no detectable effects on its kinematics. These preliminary results might be interpreted as the effect of an impaired supraspinal dopaminergic control with possible action on spinal structures involved in the control of gait. If confirmed in future studies, this mild EMG abnormality might constitute an additional supportive feature for the diagnosis of RLS in difficult cases.

CSF hypocretin-1 measurements were performed during a period of hypersomnia and during an asymptomatic interval in a 14-year-old girl affected with severe Kleine-Levin syndrome. A twofold decrease in hypocretin-1 was evidenced during the period of hypersomnia in comparison with the asymptomatic interval. Together with previous data, this result is in favour of recurrent dysfunction at the hypothalamic level in Kleine-Levin syndrome.

To describe the treatment response with melatonin for rapid eye movement (REM) sleep behavior disorder (RBD) associated with other neurologic disorders. Clonazepam has been considered the treatment of choice for RBD. However, an alternative treatment is desirable for those with RBD refractory to clonazepam, for those who experience intolerable side-effects with clonazepam, and for those in whom clonazepam precipitates or aggravates obstructive sleep apnea (OSA). To date, there is minimal published data and limited follow-up regarding the use of melatonin for patients with RBD associated with other neurologic syndromes and disorders. The response to melatonin treatment for RBD was reviewed on consecutive patients the investigators treated with this agent at Mayo Clinic Rochester from January 2000 to June 2001. The coexisting neurologic disorders, reasons for using melatonin, effective doses, side-effects, and duration of follow-up were also reviewed on all patients. Fourteen patients were commenced on melatonin over the specified time period (13 male, median RBD onset age 56 years, range 20-77 years). The coexisting neurologic findings/disorders were dementia with Lewy bodies (n=7), mild cognitive impairment with mild parkinsonism (n=2), multiple system atrophy (n=2), narcolepsy (n=2), and Parkinson's disease (n=1). The reasons for using melatonin in these cases were incomplete response of RBD to clonazepam in six patients, existing cognitive impairment in five, intolerable side-effects with clonazepam in two, and presence of severe obstructive sleep apnea and narcolepsy in one. With seven patients continuing to use clonazepam at 0.5-1.0 mg/night, RBD was controlled in six patients, significantly improved in four, and initially improved but subsequently returned in two; no improvement occurred in one patient and increased RBD frequency/severity occurred in one patient. The effective melatonin doses were 3 mg in two cases, 6 mg in seven cases, 9 mg in one case, and 12 mg in two cases. Five patients reported side-effects, which included morning headaches (2), morning sleepiness (2), and delusions/hallucinations (1); these symptoms resolved with decreased dosage. The mean duration of follow-up was 14 months (range 9-25 months), with eight patients experiencing continued benefit with melatonin beyond 12 months of therapy. In this series, persistent benefit with melatonin beyond 1 year of therapy occurred in most but not all patients. Melatonin can be considered as a possible sole or add-on therapy in select patients with RBD. Prospective, long-term, controlled trials with melatonin are warranted in a larger number of patients with RBD associated with a variety of neurologic symptoms and disorders.

Sleep disturbance is a common symptom of tobacco withdrawal and might contribute to early relapse vulnerability in abstinent smokers. This study was designed to compare the effects on sleep of nicotine patches applied either for 24 h (Nicopatch) or 16 h (Nicorette). During a short smoking cessation period (48 h), this open-label, randomised, two-period crossover study compared the effects on sleep of the two nicotine patches in 20 heavy smokers (9 women, 11 men). During each period, polysomnographic recordings were performed from 12 pm to 7 am for two consecutive nights (baseline and treatment nights). Smoking cessation started from 8 pm the day of the baseline sleep recordings, and treatments were applied around 8 am the following morning. Compared to the 16-h nicotine patch, smokers who received the 24-h nicotine patch experienced significantly less microarousals, a greater proportion of slow wave sleep, a higher REM density and higher rapid eye movement (REM) beta activities. The results of this study suggest that a 24-h nicotine patch is more efficient than a 16-h nicotine patch to alleviate tobacco withdrawal-induced sleep disturbances.

To design a new quality of life (QoL) instrument specifically for insomnia. Based on severe insomniacs' interviews, we have built a new quality of life scale that has been tested in one group of 240 severe insomniacs, in one group of 422 mild insomniacs and in one group of 391 good sleepers. Ten steps led to the construction of a specific QoL scale. Five dimensions have been validated as both relevant and independent from each other. Sixteen items out of the 43 initially tested were retained and significantly different within the groups in each dimension. Based on the 16 items selected, we called the scale Hotel Dieu 16 (HD-16). We have therefore verified the score's specificity (correlation score of +0.36) and the reliability of the scale (Cronbach coefficient alpha=0.78). HD-16 may be used as a focused instrument to better assess an insomniac's quality of life.