Ambient air pollution, dietary patterns, and the risk of incident cerebrovascular diseases: A prospective cohort study

While recent research suggests air pollution and diet interactively influence cerebrovascular health, prospective studies integrating socioeconomic and geographic factors remain limited. We investigated associations between air pollutants and cerebrovascular diseases, emphasizing modification effects of dietary patterns across stratified populations. In a cohort of 249,044 UK Biobank participants, Cox proportional hazard models and restricted cubic spline regressions were used to evaluate associations of four air pollutants (PM_2.5, PM_2.5-10, NO_2, and NO_X) with seven cerebrovascular outcomes. Stratification analyses included sociodemographic (sex, age, body mass index, Townsend Deprivation Index (TDI), occupation), lifestyle (smoking, alcohol), and geographic factors. Dietary interactions were assessed via pollutant-diet cross-product terms across five food groups. Over a median follow-up of 10.8 years, 11,369 cases of cerebrovascular diseases were identified. PM_2.5 increased sequelae risk (HR = 1.102, 95 % CI: 1.039-1.169), particularly among males (1.132, 1.034-1.239) and adults ≥65 years (1.211, 1.098-1.335). PM_2.5-10 reduced transient cerebral ischaemic attacks risk in non-drinkers (0.746, 0.577-0.964). Stratified analyses revealed heightened PM_2.5-cerebrovascular diseases association in high-TDI populations (1.079, 1.058-1.101), manual workers (1.065, 1.010-1.121), and urban residents (1.096, 1.026-1.172). Regarding dietary patterns, grain product intake attenuated PM_2.5 effects on cerebrovascular diseases risk (0.938, 0.893-0.986). Fruit intake reduced PM_2.5-10-related sequelae risk (0.844, 0.748-0.952), particularly among high-TDI populations (0.833, 0.727-0.954) and urban residents (0.846, 0.738-0.969). This study indicates that prolonged exposure to ambient air pollutants may elevate the risk of cerebrovascular diseases, highlighting the importance of adhering to a healthy diet to mitigate the risk associated with air pollution.