Impact of sleep chronotype on in-laboratory polysomnography parameters.

Morningness-eveningness preference, also known as chronotype, is the tendency for a person to sleep during certain hours of the day and is broadly categorised into morning and evening types. In-laboratory polysomnography (iPSG) is the gold-standard to assess sleep, however, an individual's chronotype is not accounted for in current protocols, which may confound collected sleep data. The objective of our study was to assess if chronotype had an association with sleep physiology. Patients who completed the diagnostic iPSG and the Morningness-Eveningness Questionnaire (MEQ), which categorises patients into morning type, neither or evening type, were assessed. Multivariable linear regression models were used to assess if chronotype was associated with sleep quality, duration, and physiology during iPSG. The study sample included 2612 patients (mean age of 53.6 years, 48% male) recruited during 2010-2015. Morning type, compared with neither type, was significantly associated with an increase in total sleep time and rapid eye movement (REM) sleep, and a decrease in sleep onset latency and the arousal index. Evening type, compared with neither type, was significantly associated with a decrease in total sleep time, sleep efficiency, and REM sleep, and an increase in sleep onset latency and wake after sleep onset. Additionally, iPSG lights out time was significantly different between the different chronotypes. Overall, a morningness chronotype was associated with favourable sleep quality and duration while an eveningness chronotype was associated with reduced sleep quality. Our study quantifies the association of chronotype with iPSG metrics and suggests that laboratory protocols should consider chronotype in their evaluations.

Strengthening oropharyngeal muscles as an approach to treat post-stroke obstructive sleep apnea: A feasibility randomised controlled trial.

This study aimed to determine the feasibility of a randomised controlled trial (RCT) evaluating oropharyngeal exercise (OPE) intervention as an alternative therapy for obstructive sleep apnea (OSA) in patients with stroke or transient ischaemic attack (TIA). Despite the high prevalence of OSA in this population, the standard therapy, continuous positive airway pressure (CPAP), is often poorly tolerated. Thirty stroke/TIA patients with OSA unable to tolerate CPAP were randomly assigned to an oropharyngeal exercise or sham exercise protocol. They performed exercises for 6 weeks, 5 days per week, 30 minutes twice per day. Feasibility was ascertained by the proportion of enrolled patients who completed more than 80% of the OPE regimen. Isometric tongue pressures, apnea-hypopnea index (AHI), oxygen desaturation index (ODI), daytime sleepiness, and quality of life (QOL) outcomes were collected at baseline, post-training (6-week follow-up), and retention (10-week follow-up) to document preliminary efficacy. Adherence to study exercises was excellent, with 83% of participants completing more than 80% of the exercises. The isometric tongue pressures were observed to improve in the oropharyngeal exercise group (compared with the sham group), along with a decrease in OSA severity (measured by the AHI and ODI), reduced daytime sleepiness, and enhanced quality of life outcomes following the exercise programme. Only the effects on posterior isometric tongue pressure and daytime sleepiness remained significantly different between groups at the retention session. In conclusion, an RCT evaluating the efficacy of oropharyngeal exercises on post-stroke/TIA OSA is feasible and our preliminary results suggest a clinically meaningful effect.

Laxatives are Associated with Poorer Polysomnography-derived Sleep Quality.

OBJECTIVE: To characterize 1) the relationship between laxative use and objective sleep metrics, and 2) the relationship between laxative use and self-reported insomnia symptoms in a convenience sample of middle-aged/elderly patients who completed in-laboratory polysomnography. METHODS: We cross-sectionally analyzed first-night diagnostic in-laboratory polysomnography data for 2946 patients over the age of 40 (mean age 60.5 years; 48.3% male). Laxative use and medical comorbidities were obtained through self-reported questionnaires. Patient insomnia symptoms were based on self-report. Associations between laxative use and objective sleep continuity were analyzed using multivariable linear regression models. Associations between laxative use and insomnia were assessed using multivariable logistic regression models. RESULTS: After adjusting for age, sex, body mass index, total recording time, and relevant comorbidities, laxative users had a 7.1% lower sleep efficiency (p < 0.001), 25.5-minute higher wake after sleep onset (p < 0.001), and a 29.4-minute lower total sleep time (p < 0.001) than patients not using laxatives. Laxative users were found to be at greater odds of reporting insomnia symptoms (OR = 1.7, p = 0.024) than patients not using laxatives. CONCLUSION: Laxative use is associated with impairments in objective sleep continuity. Patients using laxatives were also at greater odds of reporting insomnia symptoms.

Sex Differences in Obstructive Sleep Apnea after Stroke.

BACKGROUND AND OBJECTIVES: Obstructive sleep apnea (OSA) is prevalent after stroke and associated with recurrent stroke, prolonged hospitalization, and decreased functional recovery. Sex differences in post-stroke OSA remain underexplored. The objective of this study was to evaluate sex differences in functional outcomes, stroke and OSA severity, and clinical manifestations of OSA in stroke patients with OSA. METHODS: We retrospectively evaluated data from three previously conducted studies. Study patients had an imaging-confirmed stroke and had been found to have OSA (apnea-hypopnea index [AHI] ≥ 5) on either in-laboratory polysomnography or home sleep apnea testing performed within 1 year of their stroke. Linear regression models were used to evaluate study outcomes. RESULTS: In total, 171 participants with post-stroke OSA (117 males [68.4%] and 54 females [31.6%]) were included. Female sex was an independent predictor for greater functional impairment (ß = 0.37, 95% CI 0.029-0.71, p = 0.03), increased stroke severity (ß = 1.009, 95% CI 0.032-1.99, p = 0.04), and greater post-stroke depressive symptoms (ß = 3.73, 95% CI 0.16-7.29, p = 0.04). Female sex was associated with lower OSA severity, as measured by the AHI (ß = -5.93, 95% CI -11.21- -0.66). Sex was not an independent predictor of specific symptoms of OSA such as daytime sleepiness, snoring, tiredness, and observed apneas. CONCLUSION: Females with post-stroke OSA had poorer functional outcomes and more severe strokes compared to males, despite having lower OSA severity. Females with post-stroke OSA also exhibited more depressive symptoms. Understanding sex differences in patients with post-stroke OSA will likely facilitate better recognition of OSA and potentially improve clinical outcomes.

SLEAP SMART (Sleep Apnea Screening Using Mobile Ambulatory Recorders After TIA/Stroke): A Randomized Controlled Trial.

BACKGROUND AND PURPOSE: Poststroke/transient ischemic attack obstructive sleep apnea (OSA) is prevalent, linked with numerous unfavorable health consequences, but remains underdiagnosed. Reasons include patient inconvenience and costs associated with use of in-laboratory polysomnography (iPSG), the current standard tool. Fortunately, home sleep apnea testing (HSAT) can accurately diagnose OSA and is potentially more convenient and cost-effective compared with iPSG. Our objective was to assess whether screening for OSA in patients with stroke/transient ischemic attack using HSAT, compared with standard of care using iPSG, increased diagnosis and treatment of OSA, improved clinical outcomes and patient experiences with sleep testing, and was a cost-effective approach. METHODS: We consecutively recruited 250 patients who had sustained a stroke/transient ischemic attack within the past 6 months. Patients were randomized (1:1) to use of (1) HSAT versus (2) iPSG. Patients completed assessments and questionnaires at baseline and 6-month follow-up appointments. Patients diagnosed with OSA were offered continuous positive airway pressure. The primary outcome was compared between study arms via an intention-to-treat analysis. RESULTS: At 6 months, 94 patients completed HSAT and 71 patients completed iPSG. A significantly greater proportion of patients in the HSAT arm were diagnosed with OSA (48.8% versus 35.2%, P=0.04) compared with the iPSG arm. Furthermore, patients assigned to HSAT, compared with iPSG, were more likely to be prescribed continuous positive airway pressure (40.0% versus 27.2%), report significantly reduced sleepiness, and a greater ability to perform daily activities. Moreover, a significantly greater proportion of patients reported a positive experience with sleep testing in the HSAT arm compared with the iPSG arm (89.4% versus 31.1%). Finally, a cost-effectiveness analysis revealed that HSAT was economically attractive for the detection of OSA compared with iPSG. CONCLUSIONS: In patients with stroke/transient ischemic attack, use of HSAT compared with iPSG increases the rate of OSA diagnosis and treatment, reduces daytime sleepiness, improves functional outcomes and experiences with sleep testing, and could be an economically attractive approach. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02454023.

Narcolepsy Treatment: Voices of Adolescents.

INTRODUCTION: Narcolepsy, characterized by excessive daytime sleepiness, is a debilitating lifelong sleep disorder for which there is no cure. Current pharmacological and nonpharmacological treatments directed toward symptom management may be suboptimal. This qualitative study explores the perspective of adolescents on therapeutic interventions for narcolepsy. METHODS: Semi-structured interviews with adolescents with narcolepsy were conducted from May to August 2019 at The Hospital for Sick Children in Toronto, Canada. Qualitative thematic analysis was utilized to generate themes emerging from the data. RESULTS: Eighteen adolescents with narcolepsy (age range = 10-17, mean age = 14.4 ± 2.0 years, 72% male) participated and 56% had cataplexy. Four prominent themes arose regarding therapeutic interventions for narcolepsy. Firstly, participants described that pharmacotherapy was moderately effective but did not fully relieve symptoms associated with narcolepsy. Secondly, while medications are the first line treatment for narcolepsy, many participants reported frustration regarding medication dependence and side effects. Thirdly, nonpharmacological strategies including scheduled sleep times and exercise were accepted and often employed. Lastly, adolescents desired more psychosocial support to address mental health sequelae of narcolepsy that were not fully managed by current treatment modalities. CONCLUSIONS: Medications were perceived as moderately effective for managing narcolepsy but almost all participants expressed concerns with taking medications due to side effects. Adolescents valued the importance of more holistic care for their narcolepsy treatment such as psychosocial support and nonpharmacological modalities. Further anticipatory guidance regarding pharmacological side effect profiles and better integration with nonpharmacological modalities are needed to improve disease control in adolescent patients.

Ethnic and Immigrant Variations in the Time Trends of Dementia and Parkinsonism.

OBJECTIVE: We assessed long-term incidence and prevalence trends of dementia and parkinsonism across major ethnic and immigrant groups in Ontario. METHODS: Linking administrative databases, we established two cohorts (dementia 2001-2014 and parkinsonism 2001-2015) of all residents aged 20 to 100 years with incident diagnosis of dementia (N = 387,937) or parkinsonism (N = 59,617). We calculated age- and sex-standardized incidence and prevalence of dementia and parkinsonism by immigrant status and ethnic groups (Chinese, South Asian, and the General Population). We assessed incidence and prevalence trends using Poisson regression and Cochran-Armitage trend tests. RESULTS: Across selected ethnic groups, dementia incidence and prevalence were higher in long-term residents than recent or longer-term immigrants from 2001 to 2014. During this period, age- and sex-standardized incidence of dementia in Chinese, South Asian, and the General Population increased, respectively, among longer-term immigrants (by 41%, 58%, and 42%) and long-term residents (28%, 7%, and 4%), and to a lesser degree among recent immigrants. The small number of cases precluded us from assessing parkinsonism incidence trends. For Chinese, South Asian, and the General Population, respectively, prevalence of dementia and parkinsonism modestly increased over time among recent immigrants but significantly increased among longer-term immigrants (dementia: 134%, 217%, and 117%; parkinsonism: 55%, 54%, and 43%) and long-term residents (dementia: 97%, 132%, and 71%; parkinsonism: 18%, 30%, and 29%). Adjustment for pre-existing conditions did not appear to explain incidence trends, except for stroke and coronary artery disease as potential drivers of dementia incidence. CONCLUSION: Recent immigrants across major ethnic groups in Ontario had considerably lower rates of dementia and parkinsonism than long-term residents, but this difference diminished with longer-term immigrants.

Embolic Stroke of Undetermined Source and Sleep Disorders.

Background and Purpose- Compared with other causes of ischemic stroke, the mechanism of action of embolic stroke of undetermined source (ESUS) remains unclear, with previous literature suggesting that ESUS may be due to an undetected cardioembolic source. This study aimed to improve our understanding of the pathophysiology of ESUS through current knowledge of sleep disorders. Methods- Patients were included in this study if they sustained an ischemic stroke and completed either polysomnography or a home sleep apnea test. Strokes were classified into 1 of 6 mechanisms and were compared with the presence of sleep disorders (ie, obstructive sleep apnea, periodic limb movements, and abnormalities in sleep architecture). Results- There was a significant relationship between obstructive sleep apnea and cardioembolic stroke mechanism compared with the other stroke mechanisms (P=0.018). There was no significant relationship between obstructive sleep apnea and ESUS (P=0.585). Patients with ESUS were significantly more likely to have an elevated periodic limb movement index (P=0.037) and prolonged sleep onset latency (P=0.0166) compared with patients with other causes of stroke. Conclusions- ESUS was not associated with markers of cardioembolic stroke such as obstructive sleep apnea. There was a significant relationship between ESUS and elevated periodic limb movements and impaired sleep architecture, which suggests that ESUS may have a multifactorial underlying pathophysiology.

Clinical Characteristics of Cataplectic Attacks in Type 1 Narcolepsy.

PURPOSE OF REVIEW: Narcolepsy is a central disorder of hypersomnolence with symptoms of excessive daytime sleepiness, sleep paralysis, and cataplexy. Cataplexy is the sudden loss of muscle tone in either the face, neck, trunk, and/or limbs, leading to a loss of voluntary muscle control. This article reviews recent research on the clinical characteristics of cataplexy. RECENT FINDINGS: Longitudinal research in adults suggests that there may be a remission of cataplectic severity after symptom stabilization. First-line treatment options for cataplexy include sodium oxybate and pitolisant, with many drugs such as AXS-12, FT218, and JZP258 under investigation. Patients with cataplexy reported greater limitations of daily activities such as driving and exercise compared to patients without cataplexy. Cataplexy remains a challenge for children and adults with narcolepsy and can interfere with daily activities. There is no cure for narcolepsy, but cataplexy can be well-managed with current and promising new treatment options on the horizon.

Younger Age and Depressive Symptoms Predict High Risk of Generalized Anxiety After Stroke and Transient Ischemic Attack.

Background and Purpose- Depression and anxiety are common after stroke/transient ischemic attack (TIA). These conditions are associated with poor functional outcome and worse quality of life. However, few studies have explored predictors of poststroke risk of generalized anxiety, especially in patients without comorbid depressive symptoms. We aimed to explore predictors of high risk of generalized anxiety after stroke/TIA. Methods- Consecutive stroke and TIA referrals to the Sunnybrook Stroke Prevention Clinic over a 2-year period (April 2012-April 2014) who spoke English, were not severely aphasic, and who consented to complete neuropsychological testing were included in this analysis. Generalized anxiety and depressive symptoms were assessed using the Generalized Anxiety Disorder 7-item scale and Center for Epidemiological Studies Depression Scale, respectively. Results- Two hundred and fifty-eight patients completed the Generalized Anxiety Disorder 7-item scale, of whom 56 (22%) were at high risk for generalized anxiety (scores ≥10). Younger age (odds ratio=0.96; 95% CI, 0.93-0.99; P=0.004) and greater depressive symptoms (odds ratio=1.20; 95% CI, 1.14-1.26; P≤0.001) were significant predictors of being at high risk for generalized anxiety after stroke/TIA. Younger patients (≤50 years) were significantly more likely to be at high risk for both depression and generalized anxiety than older patients (30% versus 12%, χ2 [1, N=258]=10.98, P=0.001). Our model explained 56% of the variance in risk of generalized anxiety after stroke. In patients without severe depressive symptoms (n=193, 75%), age and severity of depressive symptoms remained the only factors associated with risk of generalized anxiety. Conclusions- Anxiety is common after stroke/TIA and is highly correlated with poststroke depressive symptoms and age, even among those without severe depressive symptoms. Given the greater frequency of both generalized anxiety and depressive symptoms in young survivors, routine screening for depression and further evaluation of anxiety after stroke/TIA is warranted.

Screening for Post-Stroke Depression and Cognitive Impairment at Baseline Predicts Long-Term Patient-Centered Outcomes After Stroke.

BACKGROUND: Independence and reintegration into community roles are important patient-centered outcomes after stroke. Depression and cognitive impairment are common post-stroke conditions that may impair long-term function even years after a stroke. However, screening for these post-stroke comorbidities remains infrequent in stroke prevention clinics and the utility of this screening for predicting long-term higher-level function has not been evaluated. AIMS: To evaluate the ability of a validated brief Depression, Obstructive sleep apnea, and Cognitive impairment screen (DOC screen) to predict long-term (2-3 years after stroke) community participation and independence in instrumental activities of daily living post stroke. METHODS: One hundred twenty-four patients (mean age, 66.3 [standard deviation = 15.7], 52.4% male) completed baseline depression and cognitive impairment screening at first stroke clinic visit, and telephone interviews 2 to 3 years post stroke to assess community independence (Frenchay Activities Index [FAI]) and participation (Reintegration to Normal Living Index [RNLI]). A subset of these patients also consented to complete detailed neuropsychological testing at baseline. Univariate and multivariate linear (FAI) and logistic (RNLI) regression analyses were used to determine the individual relationship between baseline data (predictors) and follow-up scores. RESULTS: Older age (ß = -0.17, P = .001), greater stroke severity (ß = 1.84, P = .015), more depressive (ß = -2.41, P = .023), and cognitive (ß = -2.15, P = .046) symptoms independently predicted poor instrumental activity ( R2 = .27; P < .001). Measures of executive dysfunction were the strongest correlates of poor instrumental activity. Higher depression risk was the only significant predictor of participation on the RNLI in regression modeling (odds ratio = 0.46, P = .028). CONCLUSIONS: Baseline DOC screening in stroke prevention clinics shows that symptoms of depression and cognitive impairment are independent predictors of impaired higher-level functioning and community reintegration 2 to 3 years after stroke. Novel rehabilitation and psychological interventions targeting people with these conditions are needed to improve long-term patient-centered outcomes.

Time Trends of the Incidence, Prevalence, and Mortality of Parkinsonism.

OBJECTIVES: We assessed trends in the incidence, prevalence, and post-diagnosis mortality of parkinsonism in Ontario, Canada over 18 years. We also explored the influence of a range of risk factors for brain health on the trend of incident parkinsonism. METHODS: We established an open cohort by linking population-based health administrative databases from 1996 to 2014 in Ontario. The study population comprised residents aged 20-100 years with an incident diagnosis of parkinsonism ascertained using a validated algorithm. We calculated age- and sex-standardized incidence, prevalence, and mortality of parkinsonism, stratified by young onset (20-39 years) and mid/late onset (≥40 years). We assessed trends in incidence using Poisson regression, mortality using negative binomial regression, and prevalence of parkinsonism and pre-existing conditions (e.g., head injury) using the Cochran-Armitage trend test. To better understand trends in the incidence of mid/late-onset parkinsonism, we adjusted for various pre-existing conditions in the Poisson regression model. RESULTS: From 1996 to 2014, we identified 73,129 incident cases of parkinsonism (source population of ∼10.5 million), of whom 56% were male, mean age at diagnosis was 72.6 years, and 99% had mid/late-onset parkinsonism. Over 18 years, the age- and sex-standardized incidence decreased by 13.0% for mid/late-onset parkinsonism but remained unchanged for young-onset parkinsonism. The age- and sex-standardized prevalence increased by 22.8%, while post-diagnosis mortality decreased by 5.5%. Adjustment for pre-existing conditions did not appreciably explain the declining incidence of mid/late-onset parkinsonism. CONCLUSION: Young-onset and mid/late-onset parkinsonism exhibited differing trends in incidence over 18 years in Ontario. Further research to identify other factors that may appreciably explain trends in incident parkinsonism is warranted.

Educating Stroke/TIA Patients about Obstructive Sleep Apnea after Stroke: A Randomized Feasibility Study.

BACKGROUND: Obstructive sleep apnea (OSA) occurs in about 70% of stroke and transient ischemic attack (TIA) patients and is associated with poor function and recurrent vascular events. Continuous Positive Airway Pressure (CPAP) has been shown to improve poststroke/TIA outcomes but adherence is generally poor. This study aimed to develop and conduct a preliminary assessment of educational materials for poststroke/TIA OSA. METHODS: This blinded pilot study involved the randomization of stroke/TIA patients to either an intervention group (who viewed an educational pamphlet and slideshow) or a control group (standard of care). Patient ratings were used to evaluate the educational materials. Changes in knowledge, daytime sleepiness, functional outcomes of sleep, and CPAP use were assessed at baseline and 6 months. RESULTS: Total 93% of eligible patients consented to participate. Forty-eight participants were randomized to the control group (n = 23) or intervention group (n = 25). In the intervention group, all patients agreed or strongly agreed that the information in the educational materials was useful and that the wording was easy to understand. There were no significant changes in knowledge, daytime sleepiness, and functional outcomes of sleep between both groups at 6 months. In those who used CPAP, there was no significant difference in mean hours of CPAP use at the 6-month follow-up. CONCLUSIONS: The educational program was feasible and easy to understand amongst stroke/TIA patients but did not lead to a significant change in outcomes or CPAP use. The lessons learned can be used to facilitate future development of educational materials and plan an adequately-powered trial.

Family functioning among adolescents with narcolepsy.

BACKGROUND: Narcolepsy is a sleep disorder with no cure with onset typically during adolescence. Caring for an adolescent with a lifelong medical condition can negatively impact family structure, cohesion, relationships, and overall functioning. The primary objective of this study was to evaluate family functioning in a cohort of adolescents with narcolepsy using the PedsQL Family Impact Module. The secondary objective was to compare family functioning in adolescents with narcolepsy to adolescents with chronic pain based on published data. METHODS: This was a cross-sectional study of adolescents (aged 10 to 18 years) with narcolepsy. The narcolepsy group was recruited from The Hospital for Sick Children in Toronto, Canada. Family functioning was assessed by the PedsQL family impact module total scores, which was completed by the patient's caregiver. The PedsQL family impact module yields a total scale which encompasses parent health-related quality of life, daily activities, family relationships, communication, and worry subscales. Lower scores suggest poorer family functioning. Secondary data analyses were used to compare participants' family functioning to a cohort of adolescents with chronic pain. RESULTS: Thirty adolescents with narcolepsy participated (mean age=13.8 ± 2.2 years, 76.7% male). Family functioning was impaired in this cohort of adolescents with narcolepsy and similar to adolescents with chronic pain (64.0 ± 19.8 versus 64.7 ± 19.5; P=0.849). CONCLUSION: Family functioning is impaired in adolescents with narcolepsy. Clinical teams should assess family functioning at routine clinic visits by asking about concerns and challenges related to caring for an adolescent with narcolepsy and providing resources and support as needed.

Living near major roads and the incidence of dementia, Parkinson's disease, and multiple sclerosis: a population-based cohort study.

BACKGROUND: Emerging evidence suggests that living near major roads might adversely affect cognition. However, little is known about its relationship with the incidence of dementia, Parkinson's disease, and multiple sclerosis. We aimed to investigate the association between residential proximity to major roadways and the incidence of these three neurological diseases in Ontario, Canada. METHODS: In this population-based cohort study, we assembled two population-based cohorts including all adults aged 20-50 years (about 4·4 million; multiple sclerosis cohort) and all adults aged 55-85 years (about 2·2 million; dementia or Parkinson's disease cohort) who resided in Ontario, Canada on April 1, 2001. Eligible patients were free of these neurological diseases, Ontario residents for 5 years or longer, and Canadian-born. We ascertained the individual's proximity to major roadways based on their residential postal-code address in 1996, 5 years before cohort inception. Incident diagnoses of dementia, Parkinson's disease, and multiple sclerosis were ascertained from provincial health administrative databases with validated algorithms. We assessed the associations between traffic proximity and incident dementia, Parkinson's disease, and multiple sclerosis using Cox proportional hazards models, adjusting for individual and contextual factors such as diabetes, brain injury, and neighbourhood income. We did various sensitivity analyses, such as adjusting for access to neurologists and exposure to selected air pollutants, and restricting to never movers and urban dwellers. FINDINGS: Between 2001, and 2012, we identified 243 611 incident cases of dementia, 31 577 cases of Parkinson's disease, and 9247 cases of multiple sclerosis. The adjusted hazard ratio (HR) of incident dementia was 1·07 for people living less than 50 m from a major traffic road (95% CI 1·06-1·08), 1·04 (1·02-1·05) for 50-100 m, 1·02 (1·01-1·03) for 101-200 m, and 1·00 (0·99-1·01) for 201-300 m versus further than 300 m (p for trend=0·0349). The associations were robust to sensitivity analyses and seemed stronger among urban residents, especially those who lived in major cities (HR 1·12, 95% CI 1·10-1·14 for people living <50 m from a major traffic road), and who never moved (1·12, 1·10-1·14 for people living <50 m from a major traffic road). No association was found with Parkinson's disease or multiple sclerosis. INTERPRETATION: In this large population-based cohort, living close to heavy traffic was associated with a higher incidence of dementia, but not with Parkinson's disease or multiple sclerosis. FUNDING: Health Canada (MOA-4500314182).

Outcomes of Daytime Procedures Performed by Attending Surgeons after Night Work.

BACKGROUND: Sleep loss in attending physicians has an unclear effect on patient outcomes. In this study, we examined the effect of medical care provided by physicians after midnight on the outcomes of their scheduled elective procedures performed during the day. METHODS: We conducted a population-based, retrospective, matched-cohort study in Ontario, Canada. Patients undergoing 1 of 12 elective daytime procedures performed by a physician who had treated patients from midnight to 7 a.m. were matched in a 1:1 ratio to patients undergoing the same procedure by the same physician on a day when the physician had not treated patients after midnight. Outcomes included death, readmission, complications, length of stay, and procedure duration. We used generalized estimating equations to compare outcomes between patient groups. RESULTS: We included 38,978 patients, treated by 1448 physicians, in the study, of whom 40.6% were treated at an academic center. We found no significant difference in the primary outcome (death, readmission, or complication) between patients who underwent a daytime procedure performed by a physician who had provided patient care after midnight and those who underwent a procedure performed by a physician who had not treated patients after midnight (22.2% and 22.4%, respectively; P=0.66; adjusted odds ratio, 0.99; 95% confidence interval, 0.95 to 1.03). We also found no significant difference in outcomes after stratification for academic versus nonacademic center, physician's age, or type of procedure. Secondary analyses revealed no significant difference between patient groups in length of stay or procedure duration. CONCLUSIONS: Overall, the risks of adverse outcomes of elective daytime procedures were similar whether or not the physician had provided medical services the previous night. (Funded by the University of Toronto Dean's Fund and others.).

Long-term exposure to air pollution and the incidence of multiple sclerosis: A population-based cohort study.

BACKGROUND: Evidence of the adverse neurological effects of exposure to ambient air pollution is emerging, but little is known about its effect on the development of multiple sclerosis (MS), the most common autoimmune disease of the central nervous system. OBJECTIVES: To investigate the associations between MS incidence and long-term exposures to fine particles (PM2.5), nitrogen dioxide (NO2), and ozone (O3) METHODS: We conducted a population-based cohort study to investigate the associations between long-term exposures to PM2.5, NO2, and O3 and the incidence of MS. Our study population included all Canadian-born residents aged 20-40 years who lived in the province of Ontario, Canada from 2001 to 2013. Incident MS was ascertained from a validated registry. We assigned estimates of annual concentrations of these pollutants to the residential postal codes of subjects for each year during the 13 years of follow-up. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for each pollutant separately using random-effects Cox proportional hazards models. We conducted various sensitivity analyses, such as lagging exposure up to 5 years and adjusting for access to neurological care, annual average temperature, and population density. RESULTS: Between 2001 and 2013, we identified 6203 incident cases of MS. The adjusted HR of incident MS was 0.96 (95% CI: 0.86-1.07) for PM2.5, 0.91(95% CI: 0.81-1.02) for NO2, and 1.09 (95% CI: 0.98-1.23) for O3. These results were robust to various sensitivity analyses conducted. CONCLUSIONS: In this large population-based cohort, we did not observe significant associations between MS incidence and long-term exposures to PM2.5, NO2, and O3 in adults in Ontario, 2001-2013.