Association between total antioxidant capacity and prevalence of depression: NHANES 2007-2018.

Background: Globally, depression is a serious public health problem with high incidence and recurrence rate. Although studies analyzed the association between different oxidative stress components and depression, few of them have explored the effect of total antioxidant capacity on depression. We aimed to explore the cross-sectional association of total antioxidant capacity with depression prevalence by sex group, and whether there was an interaction between the total antioxidant capacity and other exposures.

Methods: This study analyzed data from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2018. A total of 24,375 participants were included. The Composite Dietary Antioxidant Index (CDAI) and the Oxidative Balance Score (OBS) were used to estimate the antioxidant capacity. The association between total antioxidant capacity and depression were analyzed using binary logistic regression.

Results: Both CDAI and OBS were inversely associated with the prevalence of depression (P < 0.05). There was an interaction between OBS and hypertension (P-interaction = 0.043), and none of the other variables (including sex) had a statistically significant interaction with OBS. Higher levels of OBS were strongly associated with lower odds ratio of depression, especially in the non-hypertensive group. There were three subgroups that had lower odds ratio of depression compared with the OBS 1 combined hypertension subgroup (P < 0.05).

Conclusion: Higher total antioxidant capacity was significantly associated with lower odds ratio of depression. An interaction existed between OBS and hypertension in the whole sample. The inverse association between OBS and depression was clearer in individuals without hypertension than in individuals with hypertension.