Depressive symptoms and oxidative DNA damage in Japanese municipal employees

Abstract

We sought to explore the relationship between depressive symptoms and urinary 8-hydroxydeoxyguanine (8-OHdG), a biomarker of systemic oxidative DNA damage and repair, among 301 men and 210 women aged 21–67 years working in two municipal offices. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression scale (CES-D). The geometric mean and its 95% confidence interval (CI) of urinary 8-OHdG concentrations were calculated according to the quartile of CES-D score. The prevalence of depressive symptoms, defined as having CES_D of ≥16, was 35.9% in men and 35.2% in women. There was no significant difference in geometric mean of urinary 8-OHdG concentrations according to the levels of depressive symptoms. In men, the multivariable-adjusted geometric mean of urinary 8-OHdG concentrations (95% CIs) in the first, second, third, and fourth category of depressive symptoms was 1.09 (1.02–1.16), 1.16 (1.08–1.24), 1.15 (1.07–1.24), and 1.10 (1.02–1.18), respectively (p for trend=0.86). Similarly, no significant association was found in the analyses among women, nonsmoking men, and smoking men. The lack of association between depressive symptoms and urinary 8-OHdG concentrations may indicate the absence or more complex interactions between milder forms of depression and systemic oxidative DNA damage and repair in well-functioning population.