Prospective study of job insecurity and coronary heart disease in US women

PURPOSE: To examine prospectively the relationship between job insecurity and incidence of coronary heart disease (CHD) among women. METHODS: We conducted the study in 36,910 women from the Nurses' Health Study, a prospective cohort of female registered nurses residing in 11 US states. These women were 46 to 71 years old, and did not have diagnosed CHD, stroke, or cancer at baseline (1992). We collected information on job insecurity in 1992 and coronary heart disease incidence between baseline (June 1, 1992) and return of the 1996 questionnaire. RESULTS: During 4 years of follow-up, we documented 154 incident cases of CHD (113 non-fatal cases of myocardial infarction (MI) and 41 CHD deaths). After adjustment for a wide array of potential confounders, the relative risk (RR) of total CHD over 2-year follow-up was 1.35 (95% CI, 0.78-2.34) and 1.04 (95% CI, 0.69-1.57) over 4-year follow-up. Job insecurity appeared to significantly increase the risk of non-fatal MI in the short term (2-year follow-up: RR=1.89, 95% CI, 1.03-3.50), though not over a longer follow-up period (RR=1.28, 95% CI, 0.82-2.00), nor fatal CHD in the short term (RR=0.49, 95% CI, 0.22-2.08). CONCLUSION: These data suggest that job insecurity may increase the short-term risk of non-fatal MI in women.