Association of dietary antioxidant intake with depression risk and all-cause mortality in people with prediabetes.

People with diabetes has an elevated risk of depression, and depression contributes to a worse prognosis for people with diabetes. Dietary antioxidants have been shown to reduce the risk of depression in the general population. Therefore, we hypothesized that dietary antioxidants would also help to reduce the risk of depression and all-cause mortality in people with prediabetes. A total of 8789 participants aged 20 years and older from the 2005-2018 National Health and Nutrition Examination Surveys who met the diagnostic criteria for prediabetes were included in our study. The associations between six dietary antioxidant intakes and the composite dietary antioxidant index (CDAI) with depression risk and all-cause mortality were assessed using weighted logistic and Cox regression. Possible nonlinear associations were further explored using restricted cubic spline. To ensure the reliability of the findings, the multiple imputations by chained equation were applied to missing covariates to avoid potential bias. Our study found that moderate dietary antioxidant intake prevents depression and improves prognosis in people with prediabetes. Moreover, a CDAI score near three allows for maximum benefit. Our findings could provide clues for early intervention in people with diabetes.