Residential proximity to major roadway and progression in physical disability in older adults in China.

Evidence of a connection between living near major roadway and adverse health outcome has come to light. However, little is known about the effect of residential traffic exposure on aging-related physical disability and whether this effect can be modified. We used data derived from Chinese Longitudinal Healthy Longevity Surveys in 2018, with a total of 15,771 participants aged ≥ 65. Residential proximity to major roadway was used as a surrogate for traffic-related air pollution and physical function was measured using basic and instrumental activities of daily living. Logistic regression models were adopted for the analyses. Compared with those living > 300 m from major road, participants living within 200 m had higher risk of poorer physical functioning. The peak odds ratio was observed in severe disability caused by 101-200 m distance (OR = 1.34, 95% CI: 1.08, 1.66). And this association got stronger with longer duration of living close to major road. In dichotomized analyses using 200 m as a cutoff point, the effect associated with living close to major road was greater in male and current smoker. Specially, poor physical function appears earlier in female, but less severe than that in male. The result emphasizes the adverse effect of residential proximity to major roadways to aging-related declines in health-especially for basic living ability. This association was more pronounced in male and current smokers, which cannot be reversed by lowering the indoor air pollution.