Association between serum albumin-to-globulin ratio and diabetic retinopathy: A cross-sectional study based on the 2001-2020 NHANES database.

ObjectiveThis cross-sectional study, based on the National Health and Nutrition Examination Survey (NHANES), investigated the association between the serum albumin-to-globulin (A/G) ratio and diabetic retinopathy (DR).MethodsWe used data from the NHANES 2001-2020 and included adult participants with diabetes who completed standardized questionnaires, physical examinations, and laboratory assessments. Multivariate logistic regression models were used to evaluate the association between serum A/G ratio and DR. Restricted cubic spline (RCS) analysis was used to assess potential nonlinear relationships. Subgroup and interaction analyses were conducted to examine the robustness of the results. Receiver operating characteristic (ROC) curves were used to evaluate the predictive performance of the A/G ratio.ResultsAmong 5,868 adult participants with diabetes, 1,268 had DR. After full adjustment, the results showed that a higher A/G ratio was significantly associated with lower odds of DR [OR (95% CI): 0.66 (0.47,0.93)]. The association was linear (P for nonlinear = 0.276) and consistent across most subgroups, with a significant interaction for cardiovascular disease (P for interaction = 0.019). The A/G ratio showed limited discriminatory ability for DR (AUC = 0.632).ConclusionsA higher serum A/G ratio is associated with lower odds of DR. The findings suggest that the serum A/G ratio may reflect inflammatory and metabolic conditions associated with DR. Further prospective studies are needed to verify these findings and explore the underlying mechanisms.