Cardiovascular Diseases in Middle Aged and Older Adults in China: The Joint Effects and Mediation of Different Types of Physical Exercise and Neighborhood Greenness and Walkability

Abstract

Both physical exercise and built environment have been associated with cardiovascular diseases (CVDs). Yet, few studies examined the influence of different types of physical exercise and multiple dimensions of built environment, their joint effects, and whether physical exercise mediates the effect of built environment on the risk of CVDs. We investigated different types of physical exercise and two important dimensions of built environment, namely greenness and walkability, on the risk of three common CVD outcomes (i.e. hypertension, coronary heart disease, and stroke) in a Chinese population aged 40 years or older. Data were collected for 1,944 residents from 32 communities across urban, suburban, and rural areas in Longzihu district of Bengbu, a typical second-tier city in China. Physical exercise was obtained from questionnaire surveys. Built environment factors included satellite-based Normalized Difference Vegetation Index (NDVI), Walk Score index, and questionnaire-based Neighborhood Environment Walkability Scale (NEWS). Multilevel logistic regression was used to estimate the associations of physical exercise and built environment with CVDs while accounting for within-community and within-subdistrict correlations and potential confounders. Significant associations were found for reduced risk of hypertension and coronary heart disease with walking/square dancing and Tai Chi, and reduced risk of stroke with walking/square dancing. Significant associations were also identified for reduced risk of hypertension, coronary heart disease and stroke with NDVI. Lower risk of hypertension and coronary heart disease was associated with higher Walk score; and lower risk of hypertension and stroke was associated with higher NEWS-based walkability score. We observed no interactions between physical exercise and the built environment, but physical exercise partially mediated the effects of greenness and walkability on the risk of CVDs.