Job strain and autonomic indices of cardiovascular disease risk

Background Despite the epidemiological evidence linking job strain to cardiovascular disease, more insight is needed into the etiologic mechanisms. This, in turn, would help to more precisely identify risk. Methods We measured Job Strain using the Job Content Questionnaire, 8/day diary reports, and nationally standardized occupational code linkage, as well as autonomic regulation utilizing heart rate variability including spectral-derived components and QT interval variability in 36 healthy mid-aged males with varying strain jobs. The subjects wore Holter-monitors for 48 hr; this included a work and rest day. Results Job strain (P = 0.02) and low decision latitude (P = 0.004) were associated with a reduction in cardiac vagal control (HFP) persisting throughout the 48 hr Job strain was also associated with elevations in sympathetic control during working hours (P = 0.003). Conclusions The disturbed cardiovascular regulatory pattern associated with job strain may help explain the increased risk of cardiovascular diseases linked with occupational exposure.