RDW-SD is Superior to RDW-CV in Reflecting Liver Fibrosis Stage in Patients with Chronic Hepatitis B

PURPOSE: The clinical significance of the red blood cell distribution width (RDW)-coefficient of variation (RDW-CV) has been recognized in numerous diseases, but few studies have investigated the usefulness of RDW-standard deviation (RDW-SD). This study aimed to compare the utility of RDW-SD and RDW-CV in evaluating liver fibrosis stage in patients with chronic hepatitis B (CHB). PATIENTS AND METHODS: In this retrospective study, we enrolled 720 treatment-naïve CHB patients and 578 healthy controls, and evaluated their clinical parameters. In CHB patients, the associations between RDW-CV and liver fibrosis stage were analyzed as compared to RDW-SD using one-way analysis of variance (ANOVA), Spearman’s rank correlation, student’s t-test, binary logistic regression, and receiver operating characteristic (ROC) curve. RESULTS: RDW-SD, rather than RDW-CV was significantly elevated in CHB patients compared with healthy controls. Correlation analysis showed a stronger association between RDW-SD and liver fibrosis stage than RDW-CV in CHB patients. RDW-CV and RDW-SD are both independent predictors of significant fibrosis. For the diagnosis of significant fibrosis, the area under the receiver operating characteristic curve (AUC) for RDW-CV was 0.599, while for RDW-SD, it was 0.706. RDW-to-platelet ratio (RPR), a novel index for liver fibrosis calculated as RDW-CV/platelet, exhibited an AUC of 0.730. This AUC increased to 0.752 when RDW-CV in the RPR formula was replaced with RDW-SD. Additionally, subgroup analyses based on age, gender, and HBeAg status showed that the AUC for RDW-SD in diagnosing significant fibrosis was significantly greater than that for RDW-CV, with statistically significant differences. CONCLUSION: RDW-SD showed superiority in reflecting liver fibrosis stage and diagnosing liver significant fibrosis than RDW-CV in treatment-naïve CHB patients.