Association Between red Cell Distribution Width/Albumin Ratio and Diabetic Lower Extremity Ulcers (DLEU) among US Outpatients in the NHANES: A Retrospective Cross-Sectional Study

Objective Diabetic foot ulcers are common chronic complications of diabetes mellitus that can lead to amputation and death in severe cases. There is limited research on the relationship between the red cell distribution width/albumin ratio and diabetic lower-extremity ulcers. The few studies that have been conducted have been in single-center inpatient settings and there is limited research in outpatient settings. This study investigated this relationship in adult outpatient clinics in the United States. Methods A retrospective cross-sectional study was conducted with 1624 participants of the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2004. Three logistic regression models were developed to assess the association between red cell distribution width/albumin ratio and diabetic lower-extremity ulcers. The ratio was analyzed as a continuous and categorical variable. Stratified analyses were performed based on age, sex, HbA1c level, and body mass index. Results The study included 1624 adults, with a mean age of 65.0 ± 12.0 years, of whom 58.8% were male. The prevalence of diabetic lower-extremity ulcers was 8.0% ( n = 131). Compared with individuals with a lower red cell distribution width/albumin ratio in T1(2.32,2.93), the adjusted OR values for the ratio and ulcers in T2(2.94,3.26), T3(3.27,7.42), and 2.07 (95% CI = 1.19∼3.61), 2.92 (95% CI = 1.63∼5.23). The association between the ratio and ulcers exhibited a non-linear relationship (nonlinear, P = .028). Conclusion These results support the hypothesis of an S-shaped relationship between red cell distribution width/albumin and diabetic lower-extremity ulcers. Monitoring the RDW/Albumin ratio could be crucial for preventing diabetic lower-extremity ulcers in outpatient settings. Regular assessments may help identify high-risk patients early, enabling timely interventions. Future studies should further assess these two factors and their underlying mechanisms.