July 18, 2012PLoS ONE126 citationsOpen Access
Job Strain, Job Insecurity, and Incident Cardiovascular Disease in the Women’s Health Study: Results from a 10-Year Prospective Study
Key Result
Women with high job strain (high demand, low control) were 38% more likely to experience an incident cardiovascular disease event over 10 years compared to women with low job strain.
Study Design
Type
Cohort (n=22,086)
Multicenter
Yes
Structured PICO
Does high job strain or job insecurity increase the risk of incident cardiovascular disease in working women?
P
Population
22,086 women participants in the Women's Health Study, mean age 57±5 years
I
Intervention
High job strain (high demand, low control), active jobs (high demand, high control), and job insecurity
C
Comparator
Low job strain (low demand, high control)
O
Outcome
Incident cardiovascular disease (composite of myocardial infarction, ischemic stroke, coronary revascularization, and CVD death) over 10 years of follow-upcomposite
High job strain and active jobs are associated with a significantly increased risk of incident cardiovascular disease among women, highlighting the importance of addressing occupational stressors in CVD prevention.
Main Result
Effect estimate: RR 1.38 (95% CI 1.08-1.77)
p-value: p=<0.05
Limitations
- Cohort consisted predominantly of white female health professionals, limiting generalizability.
- Job strain and job insecurity were measured at a single time-point.
- Job insecurity was assessed using a single-item measure.
- Potential for unmeasured personal characteristics, work-related factors, and other unmeasured confounders.
- Potential healthy worker effect, as healthier women may have participated in the workforce longer.
- Missing data on traditional CVD risk factors for a subset of participants.
- Low number of CVD deaths over the follow-up period limited statistical power for that specific endpoint.
Abstract
OBJECTIVES: Research about work-related stressors and cardiovascular disease (CVD) has produced mixed findings. Moreover, a paucity of data exists regarding the long-term associations between job strain and job insecurity and CVD among women. METHODS: We used Cox proportional hazard models to examine the relationship between job strain, job insecurity, and incident CVD over 10 years of follow-up among 22,086 participants in the Women's Health Study (mean age 57±5 years). RESULTS: During 10 years of follow-up there were 170 myocardial infarctions (MI), 163 ischemic strokes, 440 coronary revascularizations, and 52 CVD deaths. In models adjusted for age, race, education, and income, women with high job strain (high demand, low control) were 38% more likely to experience a CVD event than their counterparts who reported low job strain (low demand, high control; Rate Ratio (RR) = 1.38, 95% Confidence Interval (CI) = 1.08-1.77), and women with active jobs (high demand, high control) were 38% more likely to experience a CVD event relative to women who reported low job strain (95% CI = 1.07-1.77). Outcome-specific analyses revealed that high job strain predicted non-fatal myocardial infarction (RR = 1.67, CI = 1.04-2.70), and coronary revascularization (RR = 1.41, CI = 1.05-1.90). No evidence of an association between job insecurity and long-term CVD risk was observed. CONCLUSION: High strain and active jobs, but not job insecurity, were related to increased CVD risk among women. Both job strain and job insecurity were significantly related to CVD risk factors. With the increase of women in the workforce, these data emphasize the importance of addressing job strain in CVD prevention efforts among working women.