Job Strain Does Not Relate to Morning Level Vanilmandelic Acid in Japanese Civil Servants

Epidemiologic and clinical studies have related acute and, less frequently, chronic life stress to cardiovascular diseases. In addition, animal models suggest that chronic psychological stress could cause atherosclerosis, probably by increasing sympathetic activation. In this cross-sectional study we evaluated the association between job strain, as one of the markers of workplace stress, and the urinary excretion of Vanilmandelic acid (VMA) upon awakening as a sympathoadrenal activity marker in the morning. Subjects were 936 male and 823 female civil servants working in departments related to the municipality of a city in Toyama Prefecture, Japan, in the spring of 2001. VMA was measured by high-performance liquid chromatography. We found that there was an age dependent increase in the level of VMA and females had higher VMA levels than males. Males who were current smokers had significantly lower VMA levels than nonsmokers after adjusting for age. Job strain level did not relate to VMA concentration in urine after adjusting for age and smoking status both in men and women. In addition, working and sleeping hours as predictor variables were also not associated with urinary VMA levels upon awakening in the morning. In conclusion, it seems that job strain does not independently relate to the sympathoadrenal activity, but the interaction between job strain and other variables such as personal characteristics and environmental factors and their relation with sympathoadrenal activity should further be explored.