Mental Distress and Smoking in Relation to Cardiovascular Mortality in the United States Population

Frequent mental distress and adult smoking are prevalent population-level risk indicators that may contribute to geographic and sociodemographic disparities in cardiovascular disease (CVD) mortality in the United States. Their county-level associations with CVD mortality and major subtypes remain incompletely understood.

This nationwide ecological study included data from 3069 US counties (2016-2020). Exposure data were sourced from the County Health Rankings & Roadmaps program; mortality data were obtained from the CDC WONDER. Age-adjusted mortality rates (AAMRs) were calculated for overall CVD and key subtypes. Counties were stratified into quartiles for each exposure. Associations were assessed using generalized linear models with quasi-Poisson distributions.

Counties with higher levels of frequent mental distress and adult smoking demonstrated progressively elevated CVD mortality. Total CVD AAMR increased across distress quartiles from 365.93 to 509.24 per 100,000, with the strongest associations for acute myocardial infarction (AMI) and ischemic heart disease (IHD). Adult smoking showed a similar gradient, with total CVD mortality rising from 376.45 to 532.50 per 100,000 and the steepest increase again observed for AMI. These patterns persisted after multivariable adjustment and were most pronounced among adults aged 45-64 years, with variation across racial and urbanization strata.

Higher county-level prevalence of frequent mental distress and adult smoking was associated with higher cardiovascular mortality after adjustment for measured county-level covariates, particularly from AMI and IHD. The findings reveal substantial geographic and sociodemographic disparities, supporting integrated public health strategies that concurrently address mental health, tobacco control, and social determinants to mitigate population-level cardiovascular risk.