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BACKGROUND: Studies across the globe generally reported increased mortality risks associated with particulate matter with aerodynamic diameter [less than or equal to]2.5 [micro]m (P[M.sub.2.5]) exposure with large heterogeneity in the magnitude of reported associations and the shape of concentration-response functions (CRFs). We aimed to evaluate the impact of key study design factors (including confounders, applied exposure model, population age, and outcome definition) on P[M.sub.2.5] effect estimates by harmonizing analyses on three previously published large studies in Canada [Mortality-Air Pollution Associations in Low Exposure Environments (MAPLE), 1991-2016], the United States (Medicare, 2000-2016), and Europe [Effects of Low-Level Air Pollution: A Study in Europe (ELAPSE), 2000-2016] as much as possible. METHODS: We harmonized the study populations to individuals 65+ years of age, applied the same satellite-derived P[M.sub.2.5] exposure estimates, and selected the same sets of potential confounders and the same outcome. We evaluated whether differences in previously published effect estimates across cohorts were reduced after harmonization among these factors. Additional analyses were conducted to assess the influence of key design features on estimated risks, including adjusted covariates and exposure assessment method. A combined CRF was assessed with meta-analysis based on the extended shape-constrained health impact function (eSCHIF). RESULTS: More than 81 million participants were included, contributing 692 million person-years of follow-up. Hazard ratios and 95% confidence intervals (CIs) for all-cause mortality associated with a 5-[micro]g/[m.sup.3] increase in P[M.sub.2.5] were 1.039 (1.032, 1.046) in MAPLE, 1.025 (1.021, 1.029) in Medicare, and 1.041 (1.014, 1.069) in ELAPSE. Applying a harmonized analytical approach marginally reduced difference in the observed associations across the three studies. Magnitude of the association was affected by the adjusted covariates, exposure assessment methodology, age of the population, and marginally by outcome definition. Shape of the CRFs differed across cohorts but generally showed associations down to the lowest observed P[M.sub.2.5] levels. A common CRF suggested a monotonically increased risk down to the lowest exposure level. https://doi.org/10.1289/EHP12141, Introduction Ambient particulate matter (PM) pollution has been identified as a leading risk factor for global disease burden. (1) Evaluating the risks attributable to PM with aerodynamic diameter [less than [...]

BACKGROUND: Studies across the globe generally reported increased mortality risks associated with particulate matter with aerodynamic diameter ≤2.5 μm (PM2.5) exposure with large heterogeneity in the magnitude of reported associations and the shape of concentration-response functions (CRFs). We aimed to evaluate the impact of key study design factors (including confounders, applied exposure model, population age, and outcome definition) on PM2.5 effect estimates by harmonizing analyses on three previously published large studies in Canada [Mortality-Air Pollution Associations in Low Exposure Environments (MAPLE), 1991-2016], the United States (Medicare, 2000-2016), and Europe [Effects of Low-Level Air Pollution: A Study in Europe (ELAPSE), 2000-2016] as much as possible. METHODS: We harmonized the study populations to individuals 65+ years of age, applied the same satellite-derived PM2.5 exposure estimates, and selected the same sets of potential confounders and the same outcome. We evaluated whether differences in previously published effect estimates across cohorts were reduced after harmonization among these factors. Additional analyses were conducted to assess the influence of key design features on estimated risks, including adjusted covariates and exposure assessment method. A combined CRF was assessed with meta-analysis based on the extended shape-constrained health impact function (eSCHIF). RESULTS: More than 81 million participants were included, contributing 692 million person-years of follow-up. Hazard ratios and 95% confidence intervals (CIs) for all-cause mortality associated with a 5-μg/m³ increase in PM2.5 were 1.039 (1.032, 1.046) in MAPLE, 1.025 (1.021, 1.029) in Medicare, and 1.041 (1.014, 1.069) in ELAPSE. Applying a harmonized analytical approach marginally reduced difference in the observed associations across the three studies. Magnitude of the association was affected by the adjusted covariates, exposure assessment methodology, age of the population, and marginally by outcome definition. Shape of the CRFs differed across cohorts but generally showed associations down to the lowest observed PM2.5 levels. A common CRF suggested a monotonically increased risk down to the lowest exposure level. [ABSTRACT FROM AUTHOR]

Cooling centres provide respite, safety, and social support during extreme heat events for populations that do not have the resources to own or operate in‐home air conditioning. The objective of this study was to measure the spatial accessibility of cooling centres and analyze the associations between cooling centre access and marginalization in Montreal, Toronto, and Vancouver, Canada. The potential spatial accessibility of cooling centres within a 15‐minute walk was measured at the dissemination area scale using the two‐step floating catchment area method. A two‐stage modelling approach was used to analyze the associations between cooling centre access and marginalization. Approximately 62%, 58%, and 54% of the populations in Montreal, Toronto, and Vancouver had access to at least one cooling centre. In Montreal and Vancouver, high marginalization areas were more likely to have cooling centre access than low marginalization areas. Of the areas with cooling centre access, smaller access scores were observed in areas with high residential instability. Approximately one‐fifth of the areas in each city had no cooling centre access and high marginalization, and may be considered for future cooling centres or programs that improve accessibility to existing centres. Key Messages: More than half of the population in Montreal, Toronto, and Vancouver had access to at least one cooling centre within a 15‐minute walk.Areas of high marginalization were more likely to have cooling centre access than areas of low marginalization.Residential instability was the most important factor explaining the spatial patterning of cooling centre access. [ABSTRACT FROM AUTHOR]

Background: Ambient fine particulate air pollution with aerodynamic diameter [less than or equal to] 2.5 [micro]m ([PM.sub.2.5]) is an important contributor to the global burden of disease. Information on the shape of the concentration-response relationship at low concentrations is critical for estimating this burden, setting air quality standards, and in benefits assessments. Objectives: We examined the concentration-response relationship between [PM.sub.2.5] and nonaccidental mortality in three Canadian Census Health and Environment Cohorts (CanCHECs) based on the 1991, 1996, and 2001 census cycles linked to mobility and mortality data. Methods: Census respondents were linked with death records through 2016, resulting in 8.5 million adults, 150 million years of follow-up, and 1.5 million deaths. Using annual mailing address, we assigned time-varying contextual variables and 3-y moving-average ambient [PM.sub.2.5] at a 1x1 km spatial resolution from 1988 to 2015. We ran Cox proportional hazards models for [PM.sub.2.5] adjusted for eight subject-level indicators of socioeconomic status, seven contextual covariates, ozone, nitrogen dioxide, and combined oxidative potential. We used three statistical methods to examine the shape of the concentration-response relationship between [PM.sub.2.5] and nonaccidental mortality. Results: The mean 3-y annual average estimate of [PM.sub.2.5] exposure ranged from 6.7 to 8.0 [micro]g/[m.sup.3] over the three cohorts. We estimated a hazard ratio (HR) of 1.053 [95% confidence interval (CI): 1.041, 1.065] per 10-[micro]g/[m.sup.3] change in [PM.sub.2.5] after pooling the three cohort-specific hazard ratios, with some variation between cohorts (1.041 for the 1991 and 1996 cohorts and 1.084 for the 2001 cohort). We observed a supralinear association in all three cohorts. The lower bound of the 95% CIs exceeded unity for all concentrations in the 1991 cohort, for concentrations above 2 [micro]g/[m.sup.3] in the 1996 cohort, and above 5 [micro]g/[m.sup.3] in the 2001 cohort. Discussion: In a very large population-based cohort with up to 25 y of follow-up, [PM.sub.2.5] was associated with nonaccidental mortality at concentrations as low as 5 [micro]g/[m.sup.3]. https://doi.org/10.1289/EHP5204, Introduction Exposure to ambient fine particulate air pollution with aerodynamic diameter [less than or equal to] 2.5 [micro]m ([PM.sub.2.5]) consistently ranks among the leading risk factors for premature death and [...]

Introduction: This paper briefly describes the use of Canada Post Unaddressed Admail and a geographic information system (GIS) for survey distribution to a specific target population in a large, sparsely populated geographic area, and the effectiveness of this approach. Methods: Surveys were sent as Unaddressed Admail via Canada Post to a target population of people living within 5 km of a wind turbine in southwestern Ontario. Results: The overall response rate from 8 wind farms (in 8 counties) was 8.1%. Conclusion: This approach has the potential to save time and money, but low response rates are common, distribution is not precise and there is potential for selection bias. Despite these flaws, Unaddressed Admail is worth consideration for delivery of information, study-recruitment materials and surveys to rural, remote and specific target populations. Introduction: Nous decrivons brievement l'utilisation du service Mediaposte sans adresse de Postes Canada et dun systeme d'information geographique pour la distribution de sondages a une population cible precise sur un grand territoire peu densement peuple, ainsi que l'efficacite de cette methode d'envoi. Methodes: Nous avons utilise le service Mediaposte sans adresse de Postes Canada pour envoyer des sondages a une population cible habitant dans le sud-ouest de l'Ontario a moins de 5 kilometres d'une eolienne. Resultats: Le taux de reponse global pour les 8 parcs eoliens vises (dans 8 comtes differents) etait de 8,1%. Conclusion: Bien que cette methode puisse faire economiser temps et argent, elle n'engendre souvent qu'un faible taux de reponse, est imprecise sur le plan de la distribution et pourrait entrainer un biais de selection. Malgre ces lacunes, le service Mediaposte sans adresse reste une option a envisager pour l'envoi de renseignements, de documents de recrutement en vue d'etudes et de sondages a des populations cibles precises vivant en milieu rural et eloigne., INTRODUCTION Unaddressed Admail has the potential for use in rural or remote communities when a specific geographically based sample in a community may be expensive or difficult to reach. In [...]

Background Mortality rates in Canada have been shown to vary by population group (e.g., Indigenous peoples, immigrants) and social economic status (e.g., income levels). Mortality patterns for some groups, including Black individuals, are not as well known. The objective of this study was to assess cause-specific mortality for Black adults living in Canada. Methods Mortality inequalities between Black and White cohort members were estimated by sex using Cox proportional hazard models, based on data from the 2001, 2006 and 2011 Canadian Census Health and Environment Cohorts (CanCHECs). The CanCHEC cycles were combined and followed for mortality between Census Day and December 31, 2016 or 2019, resulting in a follow-up period of 15.6, 13.6 or 8.6 years, depending on the CanCHEC cycle. Results Ischemic heart disease mortality was the leading cause of death among adult Black males (12.9%) and females (9.8%), as it is for adult White males (16.4%) and females (12.4%). Despite reduced risk of all-cause mortality among Black males and females, compared with White cohort members, there was notable increased risk for some cause-specific mortality. For instance, in the age-adjusted model, among the 25 causes of death examined, Black males had an increased risk of dying from four causes (HIV/AIDS, prostate cancer, diabetes mellitus and cerebrovascular disease), compared with White males. Similarly, Black females were at an increased risk for 6 causes of death (HIV/AIDS, stomach cancer, corpus uteri cancer, lymphomas and multiple myeloma, diabetes mellitus, and endocrine disorders) out of the 27 causes of death examined. These relative increased risks persisted for most causes of death after adjustment for differences in important social determinants of health. Interpretation Results showed substantial variability in the risk of dying by cause of death between Black and White cohort members. An important step in reducing health inequities is the routine identification and surveillance of different health outcomes by population groups. This study helps fill that information gap. [ABSTRACT FROM AUTHOR]

Background Residential greenness has been associated with health benefits, such as lower risk of mortality, cardiovascular disease, obesity, adverse birth outcomes and asthma and better psychological health. However, the variation in greenness across socioeconomic and demographic characteristics in urban areas of Canada has not been well documented. Data and methods Respondents to the 2016 Census long-form questionnaire were assigned estimates of exposure to residential greenness based on the mean Normalized Difference Vegetation Index (NDVI) (from 2012 or the most recent year available) within a 500 m buffer around their home, based on postal code. Census weights were used to determine differences in average exposure to greenness according to selected demographic and socioeconomic characteristics. Results Mean residential greenness among the 5.3 million census respondents in urban Canada was 0.44 units of the NDVI (standard deviation = 0.18 units). Greenness was lower among immigrants (particularly recent immigrants), some groups designated as visible minorities (particularly people of Filipino ancestry), lower-income households and tenants (i.e., NDVI values ranging from 0.40 to 0.43 units). Greenness values were highest among White non-immigrants and higher-income households (i.e., NDVI values ranging from 0.46 to 0.47 units). Interpretation Given the potentially multifaceted role that greenness plays in health outcomes, the inequalities in residential greenness described here may contribute to producing or exacerbating existing health inequalities in the Canadian population. [ABSTRACT FROM AUTHOR]

Background: A growing number of epidemiological studies have linked air pollution exposure to psychological conditions. Laboratory studies indicate that air pollutants can activate the neuroendocrine stress axis and modulate stress hormone levels, which could contribute to the development or exacerbation of psychological distress. The present study examined the spatial associations between air pollutants (fine particulate matter [PM2.5], nitrogen dioxide [NO2] and ground-level ozone [O3]) and psychological distress among subjects in the most populous provinces in Canada. Data and methods: Subjects were sampled from the Canadian Community Health Survey in three regions (Quebec in 2005 [n=25,800], British Columbia and Alberta in 2005 [n=23,000], and Ontario in 2011 [n=36,000]), and were assigned estimates of annual exposure to three ambient air pollutants (PM2.5, NO2 and O3) for the same years. Individual psychological distress was assessed using the Kessler Psychological Distress Scale (K10), based on anxiety and depressive symptoms in the past month. Regression models (both ordinary least squares and simultaneous autoregressive models) were applied to estimate associations between K10 distress scores and each air pollutant, after adjusting for individual (demographic, socioeconomic and behavioural) and neighbourhood covariates. Results: Psychological distress was positively associated with PM2.5 and NO2 in all three regions, and with O3 in Quebec. However, after further adjusting for individual and neighbourhood covariates, the associations between distress and air pollution remained statistically significant only in Quebec. Conclusion: Some evidence for positive associations between psychological distress and ambient air pollution after adjusting for spatial autocorrelation was found. [ABSTRACT FROM AUTHOR]

The Canadian Census Health and Environment Cohorts (CanCHECs) are population-based linked datasets of the household population at the time of census collection. The CanCHECs combine data from respondents to the long-form census or the National Household Survey between 1991 and 2011 with administrative health data (e.g., mortality, cancer incidence, hospitalizations, emergency ambulatory care) and annual mailing address postal codes. The CanCHEC datasets are rich national data resources that can be used to measure and examine health inequalities across socioeconomic and ethnocultural dimensions for different periods and locations. These datasets can also be used to examine the effects of exposure to environmental factors on human health. Because of their large size, the CanCHECs are an excellent resource for examining rare health outcomes and small population groups. They are ideally suited for environmental health research because of their geographic coverage across all regions of Canada, their long follow-up periods and their linkage to annual postal code history. [ABSTRACT FROM AUTHOR]

Background: Walkability is positively associated with physical activity in adults. Walkability is more consistently associated with walking for transportation than recreational walking. The purpose of this study is to examine how the association between walkable neighbourhoods and physical activity varies by age and type of physical activity using a new Canadian walkability database. Data and methods: The 2016 Canadian Active Living Environments (Can-ALE) database was attached to two cross-sectional health surveys: the Canadian Health Measures Survey (CHMS; 2009 to 2015) and the Canadian Community Health Survey (CCHS; 2015 to 2016). Physical activity was measured in the CHMS using the Actical accelerometer (n = 10,987; ages 3 to 79). Unorganized physical activity outside of school among children aged 3 to 11 was reported by parents in the CHMS (n = 4,030), and physical activity data by type (recreational, transportation-based, school-based, and household and occupational) was self-reported by respondents in the CCHS (n = 105,876; ages 12 and older). Results: Walkability was positively associated with accelerometer-measured moderate-to-vigorous physical activity in youth (p < 0.05), younger adults (p < 0.0001) and older adults (p < 0.05), while walkability was negatively associated with light physical activity in youth (ages 12 to 17) and older adults (ages 60 to 79) (p < 0.05). Walkability was positively associated with self-reported transportation-based physical activity in youth (p < 0.001) and adults of all ages (p < 0.0001). Walkability was negatively associated with parent-reported unorganized physical activity of children aged 5 to 11, and children living in the most walkable neighbourhoods accumulated 10 minutes of physical activity less--on average--than those living in the least walkable neighbourhoods. Interpretation: The results of this study are consistent with previous studies indicating that walkability is more strongly associated with physical activity in adults than in children and that walkability is associated with transportation-based physical activity. Walkability is one of many built environment factors that may influence physical activity. More research is needed to identify and understand the built environment factors associated with physical activity in children and with recreational or leisure-time physical activity. [ABSTRACT FROM AUTHOR]

Background: Two-thirds of Canadian adults and one-third of Canadian children and youth are overweight or obese. There is increased interest in identifying features of the built environment--such as walkability--that facilitate lifestyle habits associated with reduced obesity and improved health. The purpose of this study is to examine how the associations between walkability and both obesity and self-rated health vary by age in Canadians using a new walkability dataset. Data and methods: The 2016 Canadian Active Living Environments (Can-ALE) database was attached to Canadian Health Measures Survey (CHMS; 2009 to 2015) data. Moderate-to-vigorous physical activity (MVPA), light physical activity (LPA) and step counts were measured in the CHMS using the Actical accelerometer (n = 10,852; ages 3 to 79). Body mass index (BMI) and waist circumference were measured in a mobile clinic. Self-rated general and mental health were assessed using a questionnaire. Results: The percentage of adults aged 40 to 59 classified as overweight or obese was 28 percentage points lower in the most walkable Can-ALE category than in the least walkable category (49.1%> vs. 77.5%, p < 0.0125). There was a significant downward linear trend in measured BMI and waist circumference across Can-ALE categories (from least to most walkable) for adults aged 18 to 59, but not for children and youth or older adults aged 60 to 79. MVPA was a significant mediating factor in the association between the Can-ALE index and BMI in adults aged 40 to 79 (and in the waist circumference of respondents aged 40 to 59). Young adults (aged 18 to 39) were more likely than older adults (aged 60 to 79) to report very good or excellent general health as walkability increased. Interpretation: Using a new and freely-available Canadian walkability index, this study observed a positive association between walkability and both measured obesity and self-rated general health in adults. Walkability is one of many built environment characteristics that should be considered when trying to understand the relative contribution of the built environment to a person's weight and overall health. [ABSTRACT FROM AUTHOR]