Background and Objectives:Amyotrophic Lateral Sclerosis (ALS) is a rare neurodegenerative disorder affecting upper and lower motor neurons. Due to its rarity and rapidly progressive nature, studying the epidemiology of ALS is challenging and a comprehensive picture of the global burden of this disease is lacking. The objective of this systematic review was to describe the global incidence and prevalence of ALS.Methods:We searched Medline, Embase, Global Health, PsycInfo, Cochrane Library, and CINAHL to identify articles published between January 1st, 2010, and May 6th, 2021. Studies that were population-based and reported estimates of prevalence, incidence, and/or mortality of ALS, were eligible for inclusion. This paper focuses on incidence and prevalence. Quality assessment was performed using a tool developed to evaluate methodology relevant to prevalence and incidence studies. This review was registered with PROSPERO, CRD42021250559.Results:This search generated 6,238 articles, of which 140 were selected for data extraction and quality assessment. Of these, 85 articles reported on incidence and 61 on prevalence of ALS. Incidence ranged from 0.26 per 100,000 person-years in Ecuador to 23.46 per 100,000 person-years in Japan. Point prevalence ranged from 1.57 per 100,000 in Iran to 11.80 per 100,000 in the United States. Many articles identified ALS cases from multiple data sources.Discussion:There is variation in reported incidence and prevalence estimates of ALS across the world. While registries are an important and powerful tool to quantify disease burden, such resources are not available everywhere. This results in gaps in reporting of the global epidemiology of ALS, as highlighted by the degree of variation (and quality) in estimates of incidence and prevalence reported in this review.

Introduction Research on the health of older Veterans in Canada is an emerging area. Few population-based studies in Canada have included older Veterans as a specific group of interest. This paper describes a cohort of self-identified Veterans within the Canadian Longitudinal Study on Aging (CLSA). Materials and Methods Using data from the CLSA baseline assessment (2011-2015), we describe sociodemographic and health characteristics along with military-related variables in a cohort of Veterans in Canada. We also estimate the number of Canadian and non-Canadian Veterans living in Canada at the time of the CLSA baseline data collection. Results We estimate that at the CLSA baseline, there were 718,893 (95% confidence interval [CI], 680,033-757,110) Canadian Veterans and 185,548 (95% CI, 165,713-205,100) non-Canadian Veterans aged 45-85 years living in Canada. Veterans were older and predominantly male compared to non-Veterans in the CLSA. Following age and sex adjustment, the distribution of sociodemographic and health characteristics was similar across all groups. The majority (> 85%) of participants in each comparison group reported self-rated general and mental health as excellent, very good, or good. Following age and sex adjustment, most characteristics across groups remained similar. One exception was mental health, where a greater proportion of Veterans screened positive for depression and anxiety relative to non-Veterans. Conclusions Using CLSA baseline data, we estimate the number of older Veterans in Canada and present descriptive data that highlight interesting differences and similarities between Veterans and non-Veterans living in Canada. Canadian and non-Canadian Veterans in the CLSA are presented separately, with the latter group having not been previously studied in Canada. This paper presents a snapshot of a cohort of self-identified Veterans within the CLSA at study baseline and highlights the potential of the CLSA as a vehicle for studying the aging Veteran population in Canada for years to come.

LAY SUMMARY Little is known about the mental health of Veterans as they get older. How does the mental health and aging process of Veterans compare to people who have not served in the military? The Canadian Longitudinal Study on Aging (CLSA) is a long-term national study of the aging adult population in Canada. A total of 51,338 participants across Canada aged 45 to 85 years were recruited at the study baseline between 2011 and 2015. Of the CLSA participants, about 4,500 self-identified as Veterans, with military service dating back as early as 1941. The goal of this study was to describe the mental health, in particular posttraumatic stress disorder (PTSD), of Veterans in the CLSA at the study baseline and examine differences across Veteran sub-groups and compared to non-Veterans.