Job strain and biological coronary risk factors: a cross-sectional study of male and female workers in a Japanese rural district.

To investigate the association between job strain and biological coronary risk factors, a demand-control questionnaire was applied to 138 male (mean age 51.5) and 166 female (50.8) workers in Japanese rural town. In Model I, workers rated as both above the median on demands and below the median on control were defined as a strain group and compared to the rest. In Model II, the effect of a multiplicative term of demands by control was tested once the component main effects were controlled. In both models, possible confounders were controlled. Men in the strain group had higher blood glucose than did the others (Model 1), and the multiplicative term was significantly associated with diastolic blood pressure in men and with Lipoprotein(a) in women (Model II). The results suggest that the demand-control model predicts coronary risk factors in Japanese rural workers, and the associations are different between genders.