Abstract
BACKGROUND: Job strain is associated with an increased coronary heart disease risk, but few large-scale studies have examined the relationship of this psychosocial characteristic with the biological risk factors that potentially mediate the job strain - heart disease association. METHODOLOGY AND PRINCIPAL FINDINGS: We pooled cross-sectional, individual-level data from eight studies comprising 47,045 participants to investigate the association between job strain and the following cardiovascular disease risk factors: diabetes, blood pressure, pulse pressure, lipid fractions, smoking, alcohol consumption, physical inactivity, obesity, and overall cardiovascular disease risk as indexed by the Framingham Risk Score. In age-, sex-, and socioeconomic status-adjusted analyses, compared to those without job strain, people with job strain were more likely to have diabetes (odds ratio 1.29; 95% CI: 1.11-1.51), to smoke (1.14; 1.08-1.20), to be physically inactive (1.34; 1.26-1.41), and to be obese (1.12; 1.04-1.20). The association between job strain and elevated Framingham risk score (1.13; 1.03-1.25) was attributable to the higher prevalence of diabetes, smoking and physical inactivity among those reporting job strain. CONCLUSIONS: In this meta-analysis of work-related stress and cardiovascular disease risk factors, job strain was linked to adverse lifestyle and diabetes. No association was observed between job strain, clinic blood pressure or blood lipids.