Women who have a lot of stress at work appear to have a greater cardiovascular risk than those with lower-stress jobs, an analysis of the Women's Health Study showed.
Both active jobs and those with a high level of strain were associated with a 38% greater relative risk of having a cardiovascular event through 10 years of follow-up, according to Michelle Albert, MD, MPH, of Brigham and Women's Hospital in Boston, and colleagues.
High job strain, in particular, was associated with higher rates of nonfatal MI (RR 1.67, 95% CI 1.04 to 2.70) and coronary revascularization (RR 1.41, 95% CI 1.05 to 1.90), the researchers reported online in PLoS One.
"With the increase of women in the workforce, these data emphasize the importance of addressing job strain in cardiovascular disease prevention efforts among working women," they wrote.
Previous studies exploring the relationship between workplace stress and cardiovascular disease risk have yielded mixed results, although analyses of predominantly male populations have generally supported a link between job stress and incident cardiovascular events. The evidence has been less clear among women, however.
So, Albert and colleagues examined data from 22,086 women (mean age 57) participating in the Women's Health Study, which randomized female health professionals to vitamin E or aspirin for the primary prevention of cardiovascular disease and cancer. Information on job-related stressors was collected in the fifth year of the study.
The women were divided into four groups depending on their level of reported job strain, which considers both demands and control in the workplace:
- Passive jobs: low demand and low control
- Active jobs: high demand and high control
- Low-strain jobs: low demand and high control
- High-strain jobs: high demand and low control
Through 10 years of follow-up in the current analysis, there were 170 MIs, 163 ischemic strokes, 440 coronary revascularizations (either CABG or percutaneous coronary intervention), and 52 deaths due to cardiovascular disease.
After adjustment for age, race, treatment arm, education, and income, cardiovascular events were more likely among women with high job strain (rate ratio 1.38, 95% CI 1.08 to 1.77) and with active jobs (RR 1.38, 95% CI 1.07 to 1.77) compared with those with low-strain jobs.
Further adjustment for symptoms of depression or anxiety and for a full range of traditional cardiovascular risk factors eliminated many of the associations, although active jobs were still associated with a greater risk of any cardiovascular event (RR 1.50, 95% CI 1.13 to 1.99) and high-strain jobs were associated with an elevated risk of MI (RR 1.80, 95% CI 1.02 to 3.21).
There was no relationship between job insecurity and long-term cardiovascular risk, however.
Albert and colleagues said that job strain could contribute to cardiovascular risk either through the behavioral responses to stress - including smoking and depression - or through physiological processes like stress-induced hypertension or metabolic syndrome.
In addition, chronic stress may result in dysregulation of the hypothalamic-pituitary-adrenal axis and the autonomic nervous system, which could have adverse biological effects.
Primary source: PLoS One
Source reference: Slopen N, et al "Job strain, job insecurity, and incident cardiovascular disease in the Women's Health Study: results from a 10-year prospective study" PLoS One 2012; DOI: 10.1371/journal.pone.0040512.