Association between prognostic nutritional index and diabetic retinopathy among U.S. diabetic adults in NHANES

Diabetic retinopathy (DR) is characterized by progressive retinal vascular damage that ultimately causes vision loss. The prognostic nutritional index (PNI), which integrates albumin and lymphocytes, serves as an indicator of an individual's inflammatory response, nutritional condition, and immune system function. This research aimed to explore the possible association between PNI and DR. This was a cross-sectional study utilizing data from the National Health and Nutrition Examination Survey (NHANES) between 2001 and 2018. Weighted logistic regression analyses were employed to assess the relationship between PNI and DR prevalence. A total of 4791 adults aged 20 years and older were included in the analysis. Results indicated a statistically significant negative correlation between PNI and DR prevalence. In the fully adjusted model, a one-unit rise in PNI corresponded to a 7% reduction in the probability of DR prevalence. Quartile analysis consistently indicated that individuals in the highest PNI quartile had notably lower odds of DR prevalence compared to those in the lowest quartile. Additionally, smooth curve fitting suggested a nonlinear relationship between PNI and DR. Subgroup analysis reinforced the strength of the inverse association between PNI and DR (all p for interaction > 0.05). This nationally representative study demonstrated a significant inverse relationship between PNI levels and DR prevalence among diabetic adults in the United States. Our findings emphasize the potential role of maintaining optimal PNI values in preventing the development of DR.