Work-based predictors of mortality: a 20-year follow-up of healthy employees.

Objectives: This study investigated the effects of the Job-Demand-Control-Support (JDC-S) model's components, workload, control, peer and supervisor social support, on the risk of all-cause mortality. Also examined was the expectation that the above work-based components interact in predicting all-cause mortality. The study's hypotheses were tested after controlling for physiological variables and health behaviors known to be risk factors for mortality.

Main Outcome Measure: The design used was prospective. Baseline data were obtained from healthy employees (N = 820) who underwent periodic health examinations in 1988. Follow-up data on all-cause mortality were obtained from the participants' computerized medical file, kept by their HMO, in 2008. The baseline data covered socioeconomic, behavioral, and biological risk factors in addition to the components of the JDC-S model. During the period of follow-up, 53 deaths were recorded. Data were analyzed using Cox regressions.

Results: Only one main effect was found: the risk of mortality was significantly lower for those reporting high levels of peer social support. The study found two significant interactions. Higher levels of control reduced the risk of mortality for the men and increased it for the women. The main effect of peer social support on mortality risk was significantly higher for those whose baseline age ranged from 38 to 43 but not for the older than 43 or the younger than 38 participants.

Conclusion: Peer social support is a protective factor, reducing the risk of mortality, while perceived control reduces the risk of mortality among men but increases it among women.