Association between residential proximity to major roadways and chronic multimorbidity among Chinese older adults: a nationwide cross-sectional study

Background Multiple negative health outcomes were linked to residential proximity to major roadways. Nevertheless, there is limited knowledge regarding the association between residential proximity to major roadways and chronic multimorbidity. Methods We used data from the 2018 wave of the Chinese Longitudinal Healthy Longevity Survey, which included 12,214 individuals aged ≥ 60. We derived the residential proximity to major roadways from self-reported data, defining chronic multimorbidity as the presence of two or more concurrent chronic diseases. A binary logistic regression model was utilized to investigate the association between residential proximity to major roadways and chronic multimorbidity. The model accounted for some demographic features, socioeconomic conditions, social participation, and health conditions. Subsequently, we conducted subgroup analyses to examine potential interaction effects. Results Residential proximity to major roadways was associated with chronic multimorbidity, even after adjusting for confounding factors. Compared with those living > 300 m from major roadways, the OR for those living 201-300 m, 101-200 m, 50-100 m, and < 50 m were increased. When subgroup analyses were conducted using a cutoff point of 200 m, the risk of chronic multimorbidity associated with residential proximity to major roadways was stronger in participants with education levels > 6 years ( P = 0.017). Conclusion Our findings provide important implications for improving residential area siting, transportation policies, and environmental regulations to reduce the risk of chronic multimorbidity caused by traffic-related exposure.