Dietary Selenium Intake and All-Cause Mortality in Diabetic Kidney Disease: A Dose-Response Relationship Based on the NHANES Observational Study.

Abstract

Objective: Substantial experimental evidence has demonstrated that selenium, an essential micronutrient with pleiotropic physiological effects, also promotes dual antioxidant and anti-inflammatory effects. Meanwhile, the epidemiological association between dietary selenium consumption and mortality risk in diabetic kidney disease (DKD) remains underexplored. This investigation demonstrated a significant association between selenium intake and all-cause mortality among adult populations with DKD.

Methods: This study analyzed data from 2183 individuals diagnosed with DKD, obtained from the National Health and Nutrition Examination Survey (NHANES) conducted between 2001 and 2014. The mortality rate was determined through linkage to the National Death Index until December 31, 2015. The hazard ratios (HRs) and their corresponding 95% confidence intervals (95% CIs) were calculated using Cox proportional hazards regression models. Kaplan-Meier survival curves were generated to examine the association between survival probabilities and selenium intake.

Results: A total of 1063 mortalities were recorded over an average follow-up period of 8 years. All-cause mortality decreased with higher selenium intake levels. Adjusted for demographic variables, dietary habits, lifestyle factors, glucose regulation, and significant comorbidities, higher selenium intake was associated with improved all-cause mortality among DKD patients (adjusted HR = 0.705, 95% CI: 0.551-0.901). A significant overall association was observed between selenium intake and all-cause mortality risk, as evidenced by restricted cubic spline (RCS) analysis (p_overall < 0.001; p_nonlinearity = 0.397).

Conclusion: Higher dietary selenium intake was significantly associated with lower risk of all-cause mortality after multivariable adjustment for confounders among individuals with DKD.