Severe housing cost burden and premature cardiovascular mortality.

Background: The proportion of people living in unaffordable housing in the U.S. has grown, and studies have documented a relationship between housing cost burden and poor cardiovascular health. We investigated the association between severe housing cost burden (SHCB) and premature mortality due to cardiovascular disease (CVD) and its subtypes overall and by sex. We further evaluated whether Medicaid expansion status moderated the association between SHCB and premature CVD mortality. Methods: We linked county-level SHCB data from the 2016-2020 American Community Survey with mortality data ascertained from national death certificate data. SHCB was measured as the percentage of households that spend ≥50 % of their income on housing and was categorized into distribution-based quintiles (1=lowest and 5=highest). States were classified based on Medicaid expansion status (expanded, late expanded, non-expanded). Multilevel-linear mixed models, adjusting for confounders, were used to estimate the adjusted rate ratios (aRR) for the association between SHCB and premature CVD mortality. Results: The highest SHCB quintile, compared to the lowest, had a 15 % higher premature CVD mortality rate (aRR=1.15; 95 %CI 1.06-1.24). Among men, the highest quintile of SHCB had a higher premature mortality rate due to ischemic heart disease (aRR=1.09; 95 %CI 1.01-1.17) and stroke (aRR=1.19; 95 %CI 1.06-1.32) compared with the lowest quintile. Compared to Medicaid expanded states, non-Medicaid expanded states had higher rates of premature CVD mortality for each SHCB quintile (Quintile 5: aRR=1.19; 95 %CI 1.02-1.36). Conclusion: Our findings suggest counties with greater SHCB, especially if situated within a non-Medicaid expansion state, have higher rates of premature CVD mortality.