August 4 | 2020

Healthy built environment: Spatial patterns and relationships of multiple exposures and deprivation in Toronto, Montreal and Vancouver.

Dany Doiron, Eleanor M. Setton, Kerolyn Shairsingh, Michael Brauer, Perry Hystad, Nancy A. Ross, Jeffrey R. Brook.

Environment International, Volume 143, 2020, 106003.


Background:Various aspects of the urban environment and neighbourhood socio-economic status interact with each other to affect health. Few studies to date have quantitatively assessed intersections of multiple urban environmental factors and their distribution across levels of deprivation.

Objectives: To explore the spatial patterns of urban environmental exposures within three large Canadian cities, assess how exposures are distributed across socio-economic deprivation gradients, and identify clusters of favourable or unfavourable environmental characteristics.

Methods: We indexed nationally standardized estimates of active living friendliness (i.e. “walkability”), NO2 air pollution, and greenness to 6-digit postal codes within the cities of Toronto, Montreal and Vancouver. We compared the distribution of within-city exposure tertiles across quintiles of material deprivation. Tertiles of each exposure were then overlaid with each other in order to identify potentially favorable (high walkability, low NO2, high greenness) and unfavorable (low walkability, high NO2, and low greenness) environments.

Results: In all three cities, high walkability was more common in least deprived areas and less prevalent in highly deprived areas. We also generally saw a greater prevalence of postal codes with high vegetation indices and low NO2 in areas with low deprivation, and a lower greenness prevalence and higher NO2 concentrations in highly deprived areas, suggesting environmental inequity is occurring. Our study showed that relatively few postal codes were simultaneously characterized by desirable or undesirable walkability, NO2 and greenness tertiles.

Discussion: Spatial analyses of multiple standardized urban environmental factors such as the ones presented in this manuscript can help refine municipal investments and policy priorities. This study illustrates a methodology to prioritize areas for interventions that increase active living and exposure to urban vegetation, as well as lower air pollution. Our results also highlight the importance of considering the intersections between the built environment and socio-economic status in city planning and urban public health decision-making.

July 20 | 2020

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.

Ismael ForoughiNeeru Gupta Dan Lawson Crouse.
Int J Environ Res Public Health. 2020 Jul 9;17(14). pii: E4939. doi: 10.3390/ijerph17144939.


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. This province is characterized largely by residents in small towns and rural areas. A cohort of all adults aged 45 and over surviving AMI and without a recent record of mental disorders was identified by linking provincial medical-administrative datasets. Residential histories were tracked over time to assign neighbourhood measures of marginalization, local climate zones, and physical activity friendliness (i.e., walkability). Cox models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the risk of healthcare use for mood and anxiety disorders over the period 2003/04-2015/16 by neighbourhood characteristics. The baseline cohort included 13,330 post-AMI patients, among whom 32.5% were found to have used healthcare services for a diagnosed mood or anxiety disorder at least once during the period of observation. Among men, an increased risk of mental health service use was found among those living in areas characterized by high ethnic concentration (HR: 1.14 (95%CI: 1.03-1.25)). Among women, the risk was significantly higher among those in materially deprived neighbourhoods (HR: 1.16 (95%CI: 1.01-1.33)). We found no convincing evidence of associations between this outcome and the other neighbourhood characteristics considered here. These results suggest that selected features of neighbourhood environments may increase the burden on the healthcare system for mental health comorbidities among adults with cardiovascular disease. Further research is needed to understand the differing needs of socioeconomically marginalized populations to improve mental health outcomes following an acute cardiac event, specifically in the context of smaller and rural communities and of universal healthcare coverage.

July 6 | 2020

A scoping review on the relations between urban form and health: a focus on Canadian quantitative evidence.

McCormack GR, Cabaj J, Orpana H, Lukic R, Blackstaffe A, Goopy S, Hagel B, Keough N, Martinson R, Chapman J, Lee C, Tang J, Fabreau G.

Health Promot Chronic Dis Prev Can. 2019 May;39(5):187-200. doi: 10.24095/hpcdp.39.5.03.


Introduction: Despite the accumulating Canadian evidence regarding the relations between urban form and health behaviours, less is known about the associations between urban form and health conditions. Our study aim was to undertake a scoping review to synthesize evidence from quantitative studies that have investigated the relationship between built environment and chronic health conditions, self-reported health and quality of life, and injuries in the Canadian adult population. Methods: From January to March 2017, we searched 13 databases to identify peer-reviewed quantitative studies from all years that estimated associations between the objectively-measured built environment and health conditions in Canadian adults. Studies under-taken within urban settings only were included. Relevant studies were catalogued and synthesized in relation to their reported study and sample design, and health outcome and built environment features. Results: Fifty-five articles met the inclusion criteria, 52 of which were published after 2008. Most single province studies were undertaken in Ontario (n = 22), Quebec (n = 12), and Alberta (n = 7). Associations between the built environment features and 11 broad health outcomes emerged from the review, including injury (n = 19), weight status (n = 19), cardiovascular disease (n = 5), depression/anxiety (n = 5), diabetes (n = 5), mortality (n = 4), self-rated health (n = 2), chronic conditions (n = 2), metabolic condi-tions (n = 2), quality of life (n = 1), and cancer (n = 1). Consistent evidence for associations between aggregate built environment indicators (e.g., walkability) and diabetes and weight and between connectivity and route features (e.g., transportation route, trails, pathways, sidewalks, street pattern, intersections, route characteristics) and injury were found. Evidence for greenspace, parks and recreation features impacting multiple health outcomes was also found. Conclusion: Within the Canadian context, the built environment is associated with a range of chronic health conditions and injury in adults, but the evidence to date has limitations. More research on the built environment and health incorporating rigorous study designs are needed to provide stronger causal evidence to inform policy and practice.

Plain Language Summary

The most frequently reported associations among Canadian studies on urban form and health outcomes were related to injury and weight status. Not all provinces and territories were represented in this review, with much of the evidence coming from studies in Ontario, Quebec, and Alberta. Objectively-measured aggregate built environment indicators, connectivity and route features, destinations, food environment, population density, and greenspace, parks and recreation features are associated with a range of modifiable health conditions and injury. This scoping review identifies that more Canadian research, with rigorous designs that allow for causal inference, is required to inform policy and practice.

June 23 | 2020

Local-Area Walkability and Socioeconomic Disparities of Cardiovascular Disease Mortality in Japan.

Koohsari MJ, Nakaya T, Hanibuchi T, Shibata A, Ishii K, Sugiyama T, Owen N, Oka K.

J Am Heart Assoc. 2020 Jun 9:e016152. doi: 10.1161/JAHA.119.016152


Background: There are spatial disparities in cardiovascular disease (CVD) mortality related to area-level socioeconomic status (SES) disadvantage, but little is known about the spatial distribution of CVD mortality according to built environment factors. We examined joint associations of neighborhood walkability attributes and SES with CVD mortality rates through linkage of Japanese national data sets.

Methods and Results: National data were used from the 1824 municipalities (of the 1880 potentially eligible municipalities) across Japan. The outcome was mortality from CVD for a 5-year period (2008-2012) for each municipality. A national index of neighborhood deprivation was used as an indicator of municipality-level SES. A national walkability index (based on population density, road density, and access to commercial areas) was calculated. Compared with higher SES municipalities, relative rates for CVD mortality were significantly higher in medium SES municipalities (relative rate, 1.05; 95% CI, 1.02-1.07) and in lower SES municipalities (relative rate, 1.09; 95% CI, 1.07-1.12). There were walkability-related gradients in CVD mortality within the high and medium SES areas, in which lower walkability was associated with higher rates of mortality; however, walkability-related CVD mortality gradients were not apparent in lower SES municipalities.

Conclusions: CVD mortality rates varied not only by area-level SES but also by walkability. Those living in areas of lower walkability were at higher risk of CVD mortality, even if the areas have a higher SES. Our findings provide a novel element of the evidence base needed to inform better allocation of services and resources for CVD prevention.

June 9 | 2020

Built Environment, Physical Activity, and Obesity: Findings from the International Physical Activity and Environment Network (IPEN) Adult Study.

Sallis JF, Cerin E, Kerr J, Adams MA, Sugiyama T, Christiansen LB, Schipperijn J, Davey R, Salvo D, Frank LD, De Bourdeaudhuij I, Owen N.

Annu Rev Public Health. 2020 Apr 2;41:119-139. doi: 10.1146/annurev-publhealth-040218-043657.


Creating more physical activity-supportive built environments is recommended by the World Health Organization for controlling noncommunicable diseases. The IPEN (International Physical Activity and Environment Network) Adult Study was undertaken to provide international evidence on associations of built environments with physical activity and weight status in 12 countries on 5 continents (n > 14,000). This article presents reanalyzed data from eight primary papers to identify patterns of findings across studies. Neighborhood environment attributes, whether measured objectively or by self-report, were strongly related to all physical activity outcomes (accelerometer-assessed total physical activity, reported walking for transport and leisure) and meaningfully related to overweight/obesity. Multivariable indexes of built environment variables were more strongly related to most outcomes than were single-environment variables. Designing activity-supportive built environments should be a higher international health priority. Results provide evidence in support of global initiatives to increase physical activity and control noncommunicable diseases while achieving sustainable development goals.

May 28 | 2020

Global Land Use Regression Model for Nitrogen Dioxide Air Pollution.

Andrew Larkin, Jeffrey A. Geddes, Randall V. Martin, Qingyang Xiao, Yang Liu, Julian D. Marshall, Michael Brauer, and Perry Hystad.

Environ. Sci. Technol. 2017, 51, 12. DOI: 10.1021/acs.est.7b01148.


Nitrogen dioxide is a common air pollutant with growing evidence of health impacts independent of other common pollutants such as ozone and particulate matter. However, the worldwide distribution of NO2 exposure and associated impacts on health is still largely uncertain. To advance global exposure estimates we created a global nitrogen dioxide (NO2) land use regression model for 2011 using annual measurements from 5,220 air monitors in 58 countries. The model captured 54% of global NO2 variation, with a mean absolute error of 3.7 ppb. Regional performance varied from R2 = 0.42 (Africa) to 0.67 (South America). Repeated 10% cross-validation using bootstrap sampling (n = 10,000) demonstrated a robust performance with respect to air monitor sampling in North America, Europe, and Asia (adjusted R2 within 2%) but not for Africa and Oceania (adjusted R2 within 11%) where NO2 monitoring data are sparse. The final model included 10 variables that captured both between and within-city spatial gradients in NO2 concentrations. Variable contributions differed between continental regions, but major roads within 100 m and satellite-derived NO2 were consistently the strongest predictors. The resulting model can be used for global risk assessments and health studies, particularly in countries without existing NO2 monitoring data or models.

May 4 | 2020

Health impact assessment of Philadelphia’s 2025 tree canopy cover goals.


Kondo MC, Mueller N, Locke DH, Roman LA, Rojas-Rueda D, Schinasi LH, Gascon M, Nieuwenhuijsen MJ.


Lancet Planet Health. 2020 Apr;4(4):e149-e157. doi: 10.1016/S2542-5196(20)30058-9




Cities across the world are undertaking ambitious projects to expand tree canopy by increasing the number of trees planted throughout public and private spaces. In epidemiological studies, greenspaces in urban environments have been associated with physical and mental health benefits for city dwellers. Greenworks Philadelphia is a plan to increase tree cover across Philadelphia (PA, USA) by the year 2025. We aimed to assess whether an increase in tree canopy or greenspace in Philadelphia could decrease mortality.


We did a greenspace health impact assessment to estimate the annual premature mortality burden for adult residents associated with projected changes in tree canopy cover in Philadelphia between 2014 and 2025. Using up-to-date exposure-response functions, we calculated the number of preventable annual premature deaths city-wide, and for areas of lower versus higher socioeconomic status, for each of three tree canopy scenarios: low, moderate and ambitious. The ambitious scenario reflected the city’s goal of 30% tree canopy cover in each of the city’s neighbourhoods; and low and moderate scenarios were based on the varying levels of plantable space across neighbourhoods.


We estimated that 403 (95% interval 298-618) premature deaths overall, including 244 (180-373) premature deaths in areas of lower socioeconomic status, could be prevented annually in Philadelphia if the city were able to meet its goal of increasing tree canopy cover to 30%.


Bringing all of Philadelphia, and particularly its poorer neighbourhoods, up to the 30% goal of tree canopy cover is not without challenge. Nevertheless, policies are warranted that value urban greening efforts as health-promoting and cost-saving measures.

April 14 | 2020

Quiet, clean, green, and active: A Navigation Guide systematic review of the impacts of spatially correlated urban exposures on a range of physical health outcomes.

Rugel EJ, Brauer M.

Environ Res. 2020 Mar 19;185:109388. [Epub ahead of print]





Recent epidemiologic analyses have considered impacts of multiple spatially correlated urban exposures, but this literature has not been systematically evaluated.


To characterize the long-term impacts of four distinct spatially correlated urban environmental exposures – traffic-related air pollution (TRAP), noise, natural spaces, and neighborhood walkability – by evaluating studies including measures of at least two such exposures in relationship to mortality, cardiovascular disease, chronic respiratory disease, allergy, type 2 diabetes, or reproductive outcomes.


Following the Navigation Guide framework, the literature was searched for studies published since 2003 and meeting predefined inclusion criteria. Identified studies were scored individually for risk of bias and all studies related to an exposure-group set were appraised for overall quality and strength of evidence.


A total of 51 individual studies (TRAP and noise: n = 29; TRAP and natural spaces: n = 10; noise and natural spaces: n = 2; TRAP, noise, and natural spaces: n = 7; TRAP, noise, natural spaces, and walkability: n = 3) were included. When TRAP and noise were considered jointly, evidence was sufficient for increased cardiovascular morbidity with higher noise exposures; sufficient for no effect of TRAP on CVD morbidity; sufficient for increased mortality with higher TRAP exposures, but limited for noise; and limited for increased adverse reproductive outcomes with higher TRAP exposures and no effect of noise. Looking at natural spaces and TRAP, there was limited evidence for lower risk of chronic respiratory disease and small increases in birthweight with greater natural space; this relationship with birthweight persisted after adjustment for noise as well. Evidence was inadequate for all other exposure groups and outcomes.


Studies that properly account for the complexity of relationships between urban form and physical health are limited but suggest that even highly correlated exposures may have distinct effects.

April 6 | 2020

Traffic-Related Air Pollution and Carotid Plaque Burden in a Canadian City With Low-Level Ambient Pollution.

Johnson M, Brook JR, Brook RD, Oiamo TH, Luginaah I, Peters PA, Spence JD.

J Am Heart Assoc. 2020 Apr 7;9(7):e013400. Epub 2020 Apr 2. DOI 10.1161/JAHA.119.013400




The association between fine particulate matter and cardiovascular disease has been convincingly demonstrated. The role of traffic-related air pollutants is less clear. To better understand the role of traffic-related air pollutants in cardiovascular disease development, we examined associations between NO2, carotid atherosclerotic plaque, and cardiometabolic disorders associated with cardiovascular disease.

Methods and Results:

Cross-sectional analyses were conducted among 2227 patients (62.9±13.8 years; 49.5% women) from the Stroke Prevention and Atherosclerosis Research Centre (SPARC) in London, Ontario, Canada. Total carotid plaque area measured by ultrasound, cardiometabolic disorders, and residential locations were provided by SPARC medical records. Long-term outdoor residential NO2 concentrations were generated by a land use regression model. Associations between NO2, total carotid plaque area, and cardiometabolic disorders were examined using multiple regression models adjusted for age, sex, smoking, and socioeconomic status. Mean NO2 was 5.4±1.6 ppb in London, Ontario. NO2 was associated with a significant increase in plaque (3.4 mm2 total carotid plaque area per 1 ppb NO2), exhibiting a linear dose-response. NO2 was also positively associated with triglycerides, total cholesterol, and the ratio of low- to high-density lipoprotein cholesterol (P<0.05). Diabetes mellitus mediated the relationship between NO2 and total carotid plaque area (P<0.05).


Our results demonstrate that even low levels of traffic-related air pollutants are linked to atherosclerotic plaque burden, an association that may be partially attributable to pollution-induced diabetes mellitus. Our findings suggest that reducing ambient concentrations in cities with NO2 below current standards would result in additional health benefits. Given the billions of people exposed to traffic emissions, our study supports the global public health significance of reducing air pollution.

March 30 | 2020

Air pollution and stunting: a missing link?

Sheela S Sinharoy, Thomas Clasen, Reynaldo Martorell.


The Lancet Global Health Comment Volume 8, Issue 4, April 2020, Pages e472-e475


Child linear growth impairment, particularly stunting, remains a global health challenge. Stunting is defined as a height-for-age Z-score more than two SDs below the WHO child growth standards reference median for age and sex. The number of children younger than 5 years who are stunted was 59 million (34%) in south Asia and 58 million (33%) in sub-Saharan Africa in 2018.1 Stunting is associated with poor child development, lower productivity and earnings in adulthood, and increased risk of chronic diseases later in life.2, 3 In this Comment, we argue that air pollution has been largely ignored as a potentially important cause of stunting, we outline a conceptual framework for how air pollution might lead to impaired linear growth in children, and we call for additional research into these mechanisms.