Do depressive symptoms correlate with oxidative stress in a sample of healthy college students?

Background and Objectives: Major depression and sub-threshold depressive symptoms are associated with health crisis. Oxidative stress may be a mechanism for major depression. In the present study, we examined the relationship between the degree of depressive symptoms and oxidative status using a reliable and inexpensive method that evaluates endogenous hydroperoxides. Methods: We conducted a cross-sectional study in 54 non-smoking college students and measured serum reactive oxygen metabolites (ROMs) and the biological antioxidant potential (BAP) as an index of oxidative status. Depressive symptoms were assessed by the Beck Depression Inventory (BDI). Results: The concentrations of ROMs did not differ between the lower BDI group (BDI < 14) and the higher BDI group (BDI >= 14) (282.7 +/- 59.84 U.CARR vs 307.7 +/- 67.51 U.CARR, z = -1.19, P = 0.239). We did find a significant relationship between ROM concentration values and higher BDI scores (rho= 0.30, P = 0.042). BAP levels in the higher BDI group were not significantly greater than those in the lower BDI group (z = -0.108, P = 0.287). There was no significant correlation between BAP and depressive symptoms (rho = 0.22, P = 0.140). Moreover, we conducted a multiple regression analysis to control for gender difference and difference in sleep perception of the previous night between the two BDI groups. However, depressive symptoms were not significantly predicted by ROM concentrations (beta = 0.28, P = 0.076). Conclusions: While results of the present study demonstrated a slight correlation between depressive symptoms and oxidative stress, this linkage could not be confirmed after controlling for significant confounding factors. This result should be verified in a larger sample.