Association between occupational working time and cardiovascular morbidity: a cross-sectional study of NHANES database

Abstract Background Long working hours are recognized as an occupational hazard that may increase the risk of cardiovascular diseases. However, limited contemporary evidence exists from nationally representative US populations. Aims This study aimed to examine the association between occupational working time and cardiovascular morbidity using the recent National Health and Nutrition Examination Survey (NHANES) data. Methods A cross-sectional analysis including 4502 adults from the 2021–23 NHANES dataset was conducted. Working hours were categorized into 1–34, 35–40, 41–54, and ≥55 h per week. Cardiovascular outcomes included self-reported heart failure, coronary heart disease, angina, myocardial infarction, stroke and hypertension. Results Participants working 35–40 h last week had significantly lower odds of having coronary heart disease (odds ratio [OR] = 0.524; 95% confidence interval [CI] 0.275–0.998), and angina (OR = 0.411; 95% CI 0.191–0.887) compared to those working 1–34 h. Those working 41–54 h also had reduced odds of angina (OR = 0.125; 95% CI 0.029–0.550). Conversely, working ≥55 h last week was significantly associated with increased odds of hypertension (OR = 1.496; 95% CI 1.135–1.971). No significant association was found between working days per week and CV morbidity. Conclusions Standard full-time work (35–40 h/week) may be protective against certain cardiovascular conditions, while long working hours (≥55 h/week) may elevate hypertension risk. These findings support international calls to regulate excessive work hours and highlight the importance of balanced employment for better cardiovascular health.