Perceived job insecurity as a risk factor for incident coronary heart disease: systematic review and meta-analysis

OBJECTIVE: To determine the association between self reported job insecurity and incident coronary heart disease. DESIGN: A meta-analysis combining individual level data from a collaborative consortium and published studies identified by a systematic review. DATA SOURCES: We obtained individual level data from 13 cohort studies participating in the Individual-Participant-Data Meta-analysis in Working Populations Consortium. Four published prospective cohort studies were identified by searches of Medline (to August 2012) and Embase databases (to October 2012), supplemented by manual searches. REVIEW METHODS: Prospective cohort studies that reported risk estimates for clinically verified incident coronary heart disease by the level of self reported job insecurity. Two independent reviewers extracted published data. Summary estimates of association were obtained using random effects models. RESULTS: The literature search yielded four cohort studies. Together with 13 cohort studies with individual participant data, the meta-analysis comprised up to 174,438 participants with a mean follow-up of 9.7 years and 1892 incident cases of coronary heart disease. Age adjusted relative risk of high versus low job insecurity was 1.32 (95% confidence interval 1.09 to 1.59). The relative risk of job insecurity adjusted for sociodemographic and risk factors was 1.19 (1.00 to 1.42). There was no evidence of significant differences in this association by sex, age (<50 v ≥ 50 years), national unemployment rate, welfare regime, or job insecurity measure. CONCLUSIONS: The modest association between perceived job insecurity and incident coronary heart disease is partly attributable to poorer socioeconomic circumstances and less favourable risk factor profiles among people with job insecurity.