Association of the Red blood cell distribution width with Osteoarthritis Risk: A Cross-sectional Study from NHANES 2009-2018

Background： Red blood cell distribution width (RDW) is considered a novel prognostic biomarker; however, the correlation between RDW and osteoarthritis (OA) has not been clearly revealed. Therefore, this study used data from the National Health and Nutrition Examination Survey (NHANES) from 2009 to 2018 to explore the potential relationship between RDW and OA in depth. Methods： This cohort study included 13,700 eligible participants with valid RDW and OA data from the National Health and Nutrition Examination Survey (NHANES) 2009-2018. Logistic regression was used to study the relationship between RDW and OA, followed by subgroup analysis to verify the results. The accuracy of RDW in OA compared to BMI was assessed by plotting the receiver operating characteristic (ROC) curve. Additionally, a restricted cubic spline (RCS) was used to evaluate the nonlinear relationship between the two. Results： This study involved 13,700 participants. According to our findings, RDW was positively correlated with an increased risk of OA,this positive correlation persists even after adjusting for all covariates.Subgroup analysis showed that the positive correlation between RDW and OA prevalence persisted across all groups with different characteristics, confirming its validity across all populations. The results indicated that OA participants had higher RDW levels compared to non-OA participants. Additionally, restricted cubic spline (RCS) analysis revealed a significant nonlinear relationship between RDW and OA (P-nonlinear < 0.05). According to ROC curve analysis, RDW is a superior predictor of OA compared to BMI. Conclusion: Our study found that higher RDW levels are associated with an increased risk of OA.