Association of vitamin D3 and diabetic retinopathy in US adults: A cross-sectional study

The potential protective effects of vitamin D3 against diabetic retinopathy (DR) in adults have been studied. However, conflicting results exist, with some studies reporting no effect. Therefore, our goal was to assess the connection between vitamin D3 and adult DR in the United States. We investigated the relationship between vitamin D3 and DR using information from the National Health and Nutrition Examination Survey. We obtained vitamin D3 data from serum samples and DR data from doctors through a questionnaire. The main analytical methods utilized in this study were multivariable logistic regression, stratified analysis with interaction, and restricted cubic splines (RCS). A total of 1978 participants were included. There was a significant negative association between vitamin D3 and DR after accounting for potential confounders (OR: 0.995, 95% CI: 0.992-0.999; P = .0237). Compared with the T1 group (≤46.50), the fully adjusted OR for T3 (≥74.50) was 0.617 (95% CI: 0.455-0.837, P = .0019). A linear relationship was observed between vitamin D3 and DR (P = .836). There was a negative linear relationship between the level of vitamin D3 and the risk of DR among adults in the United States.