Objective The aim of this study was to determine whether elevated depressive symptoms are associated with metabolic syndrome and its components in the Japanese population.
Methods Out of 1,386 male workers who underwent measurements of variables of metabolic syndrome components in their health checkup, 1,186 subjects (44.5 ± 9.6 years) completed the Zung self-rating depression scale (ZSDS) (response rate 85.6%). In this study, metabolic syndrome was defined according to the joint scientific statement proposed by 6 major organizations, including the International Diabetes Federation.
Results The overall frequency of elevated depressive symptoms (ZSDS scores ≥40) was 42.1% (n=499). The incidence of metabolic syndrome was significantly higher in subjects with elevated depressive symptoms than in those without (13.2% vs. 8.9%, p<0.05). Of all the metabolic syndrome components, mean triglyceride levels were significantly higher in subjects with elevated depressive symptoms than in those without [124.7 (95% confidence interval (CI): 117.8-131.7) mg/dL vs. 111.5 (95% CI: 107.2-115.9) mg/dL, p<0.05]. Consequently, hypertriglyceridemia (28.9% vs. 21.0%, p<0.01) was the main component correlated with the between-group difference of metabolic syndrome incidence. In the logistic regression analysis after adjustment for potential confounders, the odds ratio of the total ZSDS scores for the diagnosis of hypertriglyceridemia was 1.52 (95% CI: 1.13-2.04; p<0.01), and the major depressive symptom was psychomotor agitation (odds ratio: 1.47; 95% CI: 1.10-1.94; p<0.01).
Conclusion This study showed that elevated depressive symptoms were associated with hypertriglyceridemia in Japanese male workers, which affected the clinical diagnosis of metabolic syndrome.