Effort-reward imbalance at work and recurrent coronary heart disease events: a 4-year prospective study of post-myocardial infarction patients.

OBJECTIVE: Prospective studies have shown that effort-reward imbalance (ERI) at work is associated with the incidence of a first coronary heart disease (CHD) event. However, it is unknown whether ERI at work increases the risk of recurrent CHD events. The objective of this study was to determine whether ERI at work and its components (effort and reward) increase the risk of recurrent CHD in post-myocardial infarction (post-MI) workers.

METHODS: We carried out a prospective cohort study of 669 men and 69 women who returned to work after a first MI. ERI at work was assessed by telephone interview using validated scales of reward and psychological demands. The outcome was a composite of fatal CHD, nonfatal MI, and unstable angina. CHD risk factors were documented in medical files and by interview. The participants were followed up for a mean period of 4.0 years (1998-2005).

RESULTS: During the follow-up, 96 CHD events were documented. High ERI and low reward were associated with recurrent CHD (respective adjusted hazard ratios [HRs] = 1.75, 95% confidence interval [CI] = 0.99-3.08, and HR = 1.77, 95% CI = 1.16-2.71). There was a gender interaction showing stronger effects among women (respective adjusted HRs for high ERI and low reward: HR = 3.95, 95% CI = 0.93-16.79, and HR = 9.53, 95% CI = 1.15-78.68).

CONCLUSIONS: Post-MI workers holding jobs that involved ERI or low reward had increased risk of recurrent CHD.