Urban active living environments and cardiovascular disease mortality: a Canadian national cohort study

Abstract

BACKGROUND AND AIM: Neighbourhoods conducive to utilitarian walking and active living are associated with higher physical activity and lower cardiovascular risk factors. Most evidence, however, has been drawn from ecological studies. Our aim was to investigate longitudinal associations between neighbourhood walkability and cardiovascular mortality in a large population-based cohort of Canadian adults. METHODS: We analyzed data from the 2001 Canadian Census Health and Environment Cohort (CanCHEC). These data were obtained from the mandatory 2001 long-form census, which includes a random sample of roughly 20% of the Canadian population. Individual-level data from the 2001 census were linked to income tax files to provide annual residential postal codes, while mortality was ascertained by linkage to the Canadian Vital Statistics Death Database between 2001 and 2016. The main exposure was the Canadian Active Living Environments (Can–ALE), a national quintile index that summarizes features of the built environment related to active living and walkability. We restricted our analysis to those 19 years of age and older at baseline who lived in large city areas (population ≥100,000), allowing individual person-years to move in and out of the analytical sample. Cox proportional hazard models were fit to estimate hazard ratios for Can–ALE categories and cardiovascular mortality while adjusting for many individual and contextual covariates. RESULTS:A total of 26,875,875 person-years (53% female) and 266,740 deaths were included in the model. Living in a highly walkable neighbourhood (Can–ALE 5 [high] vs 1 [low]) was significantly associated with a 6% reduced hazard of cardiovascular mortality (aHR: 0.94, 95%CI: 0.90, 0.98), 11% reduced hazard of cerebrovascular mortality (aHR: 0.89, 95%CI: 0.81, 0.98), and a 7% reduced hazard of ischemic heart disease mortality (aHR: 0.93, 95%CI: 0.88, 0.99). CONCLUSIONS:Living in an urban neighbourhood or community supportive of utilitarian walking and active living may contribute to lower mortality from cardiovascular disease in adults. KEYWORDS: Built environment, walkability, cardiovascular diseases, mortality