Assessing Adverse Health Effects of Long-Term Exposure to Low Levels of Ambient Air Pollution: The HEI Experience and What's Next?

Although concentrations of ambient air pollution continue to decline in high-income regions, epidemiological studies document adverse health effects at levels below current standards in many countries. The Health Effects Institute (HEI) recently completed a comprehensive research initiative to investigate the health effects of long-term exposure to low levels of air pollution in the United States (U.S.

Individual physical activity, neighbourhood active living environment and mental illness hospitalisation among adults with cardiometabolic disease: a Canadian population-based cohort analysis.

Objectives: This population-based observational study explores the associations between individual-level and neighbourhood-level indices of active living with inpatient mental healthcare use among adults with an underlying chronic cardiometabolic condition.

Design And Setting: Data from the 2013-2014 Canadian Community Health Survey were linked longitudinally to hospital records from the 2013/2014‒2017/2018 Discharge Abstract Database and to a geocoded measure of active living environments (ALE). Relationships between individuals' leisure-time physical activity and neighbourhood ALE with risk of hospital admission for mental health disorders were assessed using multivariable Cox regressions.

The Impact of Rural Hospital Closures and Health Service Restructuring on Provincial- and Community-Level Patterns of Hospital Admissions in New Brunswick.

In the early 2000s, the Province of New Brunswick, Canada, undertook health system restructuring, including closing some rural hospitals. We examined whether changes in geographic access to hospitals and primary care were associated with changes in patterns of hospital use. We described three measures of hospital use for ambulatory care sensitive conditions (ACSCs) among adults 75 years and younger annually during the period 2004-2013 overall, and at the community scale.

Neighbourhood characteristics related to mental health service use among adults with diabetes: a population-based cohort study in New Brunswick, Canada.

Objective: It has been postulated that social and economic inequalities may shape the distributions of comorbid diabetes and mental illness. This observational cohort study using linked population-based administrative and geospatial datasets aimed to describe associations between neighbourhood socioenvironments and disorder-specific mental health service use among adults with diabetes in the province of New Brunswick, Canada.

Results: A baseline cohort of 66,275 persons aged 19 and over living with diabetes was identified.

Neighbourhood walkability and mortality: Findings from a 15-year follow-up of a nationally representative cohort of Canadian adults in urban areas.

Background: Using a nationally representative cohort of Canadian adults, we assessed associations between neighbourhood walkability and cause-specific mortality and investigated whether they differed by socioeconomic status.

Methods: The study population was drawn from the 2001 Canadian Census Health and Environment Cohort, which contains individual-level data from a random sample of 20% of Canadian households mandated to complete the long-form census. We included those aged ≥ 25 years at baseline who lived in urban and suburban areas.

The influence of outdoor PM concentration at workplace on nonaccidental mortality estimates in a Canadian census-based cohort.

Background: Associations between mortality and exposure to ambient air pollution are usually explored using concentrations of residential outdoor fine particulate matter (PM) to estimate individual exposure. Such studies all have an important limitation in that they do not capture data on individual mobility throughout the day to areas where concentrations may be substantially different, leading to possible exposure misclassification. We examine the possible role of outdoor PM concentrations at work for a large population-based mortality cohort.

Gendering Neighbourhood Marginalization Metrics in Mental Health Services Research: A Cross-Sectional Exploration of a Rural and Small Urban Population.

Little is known about the extent to which socioenvironmental characteristics may influence mental health outcomes in smaller population centres or differently among women and men. This study used a gender-based analysis approach to explore individual- and neighbourhood-level sex differences in mental health service use in a context of uniquely smaller urban and rural settlements. This cross-sectional analysis leveraged multiple person-based administrative health datasets linked with geospatial datasets among the population aged 1 and over in the province of New Brunswick, Canada.

Ethnocultural and socioeconomic disparities in exposure to residential greenness within urban Canada.

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.

Provider caseload volume and short-term outcomes following colorectal surgeries in New Brunswick: a provincial-level cohort study.

Background: American studies have shown that higher provider and hospital volumes are associated with reduced risk of mortality following colorectal surgical interventions. Evidence from Canada is limited, and to our knowledge only a single study has considered outcomes other than death. We describe associations between provider surgical volume and all-cause mortality and postoperative complications following colorectal surgical interventions in New Brunswick.

Residential greenness and indicators of stress and mental well-being in a Canadian national-level survey.

Background: Residential proximity to greenness in urban areas has been shown to confer a number of health benefits, including improved mental health. We investigated whether greenness was associated with self-reported stress, distress, and mental health among adult participants of multiple cycles of a national Canadian health survey, and whether these associations varied by sex, age, income, and neighbourhood characteristics.

Methods: Our study population included 397,900 participants of the Canadian Community Health Survey, 18 years of age or older, who lived in census metropolitan areas between 2000 and 2015.

Residential Greenness and Cardiovascular Disease Incidence, Readmission, and Mortality.

Background: Living in greener areas of cities was linked to increased physical activity levels, improved mental well-being, and lowered harmful environmental exposures, all of which may affect human health. However, whether living in greener areas may be associated with lower risk of cardiovascular disease incidence, progression, and premature mortality is unclear.

Objectives: We conducted a cohort study to examine the associations between residential green spaces and the incidence of acute myocardial infarction (AMI) and heart failure (HF), post-AMI and HF hospital readmissions, and mortality.

Healthcare Service Use for Mood and Anxiety Disorders Following Acute Myocardial Infarction: A Cohort Study of the Role of Neighbourhood Socioenvironmental Characteristics in a Largely Rural Population.

Depression and other mood and anxiety disorders are recognized as common complications following cardiac events. Some studies report poorer cardiac outcomes among patients in socioeconomically marginalized neighbourhoods. This study aimed to describe associations between socioeconomic and built environment characteristics of neighbourhood environments and mental health service contacts following an acute myocardial infarction (AMI or heart attack) among adults in the province of New Brunswick, Canada.

Urban green space and the risks of dementia and stroke.

Introduction: It is unknown whether urban green space is associated with reduced risk of major neurological conditions, especially dementia and stroke.

Methods: Retrospective, population-based cohorts were created for each study outcome, including 1.7 and 4.

Provider volume and maternal complications after Caesarean section: results from a population-based study.

Background: A large literature search suggests a relationship between hospital/surgeon caseload volume and surgical complications. In this study, we describe associations between post-operative maternal complications following Caesarean section and provider caseload volume, provider years since graduation, and provider specialization, while adjusting for hospital volumes and patient characteristics.

Methods: Our analysis is based on population-based discharge abstract data for the period of April 2004 to March 2014, linked to patient and physician universal coverage registry data.

Neighbourhood environments and the risk of hospital admission for cardiometabolic and mental health comorbidities in multiple sclerosis: A population cohort analysis using linked administrative data.

This study exploits administrative data for neuroepidemiological research and examines associations between neighbourhood environments and risk of hospitalization among multiple sclerosis (MS) patients in New Brunswick, Canada. We created a provincial database of MS patients by linking administrative health records with geographic-based characteristics of local communities. Using Cox models, we found the risk of admission for cardiometabolic complications was lower among residents of ethnically homogeneous neighbourhoods (hazards ratio [HR]: 0.

Evaluating the Sensitivity of PM2.5-Mortality Associations to the Spatial and Temporal Scale of Exposure Assessment.

Background: The temporal and spatial scales of exposure assessment may influence observed associations between fine particulate air pollution (PM2.5) and mortality, but few studies have systematically examined this question.

Methods: We followed 2.

Examining the Shape of the Association between Low Levels of Fine Particulate Matter and Mortality across Three Cycles of the Canadian Census Health and Environment Cohort.

Background: Ambient fine particulate air pollution with aerodynamic diameter () 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 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.

Complex relationships between greenness, air pollution, and mortality in a population-based Canadian cohort.

Background: Epidemiological studies have consistently demonstrated that exposure to fine particulate matter (PM) is associated with increased risks of mortality. To a lesser extent, a series of studies suggest that living in greener areas is associated with reduced risks of mortality. Only a handful of studies have examined the interplay between PM, greenness, and mortality.

Exposure to traffic and mortality risk in the 1991-2011 Canadian Census Health and Environment Cohort (CanCHEC).

There is evidence that local traffic density and living near major roads can adversely affect health outcomes. We aimed to assess the relationship between local road length, proximity to primary highways, and cause-specific mortality in the 1991 Canadian Census Health and Environment Cohort (CanCHEC). In this long-term study of 2.

Associations between Living Near Water and Risk of Mortality among Urban Canadians.

Background: Increasing evidence suggests that residential exposures to natural environments, such as green spaces, are associated with many health benefits. Only a single study has examined the potential link between living near water and mortality.

Objective: We sought to examine whether residential proximity to large, natural water features (e.