High job strain – defined as high psychological demands combined with low control or decision-making ability over one's job – is associated with increased blood pressure particularly among men., not just during the workday but also at home and during sleep, according to the new research, led by Els Clays, M.Sc., of Ghent University in Belgium.
Using data from a large study of the health effects of job stress, the researchers identified 89 middle-aged Belgian workers with high job strain and a similar number of workers without high job strain. Both groups underwent 24-hour ambulatory blood-pressure monitoring, in which their blood pressure was measured at frequent intervals as they went through their regular daily activities.
The study results indicate that men with high job strain had significantly higher blood pressure.
Although blood pressures were highest at work, workers with high job strain also had increased blood pressure while they were at home and even when they were sleeping. On average, blood pressure during the workday was 6.5/3.1 mm Hg higher for the workers reporting high job strain. (Normal blood pressure is about 120/80 mm Hg.)
Workers with high job strain had increased rates of other risk factors, such as older age, increased body weight and smoking. However, the relationship between job strain and blood pressure remained significant after adjustment for these factors.
According to the researchers, detailed analysis suggested that the rise in blood pressure was more strongly related to low job control, or “decision latitude,” than to high job demands.
High job strain previously has been linked to an increased risk of cardiovascular disease, particularly in men. According to the researchers, increased blood pressure is one way in which high job strain might affect cardiovascular risk.
“Based on this and other studies, there is convincing evidence for consistent associations between self-perceived job strain and ambulatory blood pressure,” the researchers conclude.
The increases in blood pressure linked to high job strain may not seem large on the individual level, the researchers point out. However, from a public health perspective, the increases could be significant – especially since blood-pressure reductions of similar magnitude can lead to substantial reductions in heart disease risk.