Abstract
BACKGROUND: While road traffic noise is an emerging environmental risk for cardiovascular mortality, its age-group-specific effects on stroke mortality remain unclear. This study further explored socioeconomic disparities in this association. METHODS: We conducted a retrospective cohort study (2011-2019) with 36,240 hospitalized stroke patients in Fuxin, China. Residential noise levels were estimated using street view imagery analyzed by a novel and multimodal deep learning model. Age-grouped cox proportional hazards models adjusted for NO(2), NDVI (Normalized Difference Vegetation Index), and sociodemographic covariates were applied to assess mortality risks. RESULTS: Among elderly patients aged ≥60 years with lower medical insurance, each 5-dB increase in residential road noise was associated with a 93.6% increase in stroke mortality risk (HR = 1.936, 95% CI: 1.024-3.660; p = 0.042). The estimated exposure prevalence in this subgroup was 3%, yet the population attributable fraction reached 1.7%. In contrast, no significant associations were found among patients with higher insurance coverage. Younger Males had a 51.3% higher mortality risk than females (adjusted HR=1.513, 95% CI: 1.142-2.005), independent of environmental exposures. NO(2) and NDVI were not significantly associated with mortality across subgroups. CONCLUSIONS: These findings highlight the need for noise mitigation strategies that prioritize vulnerable populations, particularly the elderly and those with limited healthcare access.