Abstract Body (Do not enter title and authors here): Introduction: Unemployment increases the likelihood of cardiovascular disease mortality (CVDM) for middle-aged men in high-income nations. In the United States, both CVDM and unemployment rates have seasonal variations. There is a need to investigate whether the association between CVDM and unemployment varies by season.

Hypothesis: Unemployment will increase the risk of CVDM among middle-aged men by season.

Methods: CDC population-based study with monthly CVD deaths [ICD-10 (I00-99)] among middle-aged (20-64 years) men in Northeast (NJ, NY, PA) US from Jan 2015 to Dec 2020. For the same period, state-level monthly unemployment rates were ascertained from US Bureau of Labor Statistics; categorized as low (≤10^th percentile: ≤5%), average (5-8%), and high (≥90^thpercentile: ≥8%). With population estimates, CVDM rates were associated with unemployment rate categories by season (winter and summer) using negative binomial regression with autocorrelation upon adjusting for occupation type, maximum temperature, smoking, diabetes, asthma prevalence, college education attainment, region, and trend.

Results: There were 76,418 CVD deaths recorded. High (compared with low) unemployment rates were associated with increased risk of CVDM (Figure) during the winter [adjusted RR 1.19 (95% CI 1.15-1.24)] and summer [adjusted RR 1.21 (95% CI 1.17-1.25)]. Significant interactions were observed between unemployment rates and maximum temperatures in both seasons.

Conclusions: High unemployment rates were associated with an increased risk of CVDM among middle-aged men both in winter and summer. Yet there was no notable strong seasonal variation.
Seasonal differences were observed in the association of high unemployment rates with an increased risk of CVDM among middle-aged men. Seasonality and unemployment rates are predisposing risk factors for CVDM. Further studies should assess CVDM risk factors for other susceptible areas in the US.