Abstract: Objective   To explore the effect of the interaction between red blood cell distribution width (RDW) and high-sensitivity C-reactive protein (hsCRP) on cardiovascular events in  maintenance hemodialysis (MHD) patients.  Methods   Patients who received MHD at the Second Affiliated Hospital of Kunming Medical University from January 2020 to June 2022 were enrolled. Based on median RDW levels, patients were divided into a high-RDW (RDW≥4.75%, n=102) and a low-RDW group (RDW＜14.75%, n=102). According to hsCRP level, patients were divided into a high-hsCRP (hsCRP＞3 mg/L, n=127) and a low-hsCRP group (hsCRP≤3 mg/L, n=77). Kaplan-Meier survival curves and COX regression models were used to explore correlations between RDW and cardiovascular events across hsCRP strata and their interaction effect. A restricted cubic spline regression model was used to analyze the dose-response relationship between RDW levels and cardiovascular events.  Results   A total of 204 MHD patients were included in this study, and there were 76 cases (37.3%) of cardiovascular events during the follow-up period. Kaplan-Meier analysis revealed a significantly higher cardiovascular event incidence in the high-RDW versus low-RDW group within the high-hsCRP stratum (χ²=12.831, P＜0.001), but not in the low-hsCRP group (χ²=0.072, P=0.788).  Multivariate Cox regression analysis revealed a significant interaction between RDW and hsCRP on cardiovascular events (HR=1.001, 95% CI:1.000～1.001, P=0.014). Compared with the low-hsCRP-low RDW group，the high-hsCRP-high RDW group had a significantly higher risk of cardiovascular events (HR=2.215, 95% CI: 1.108～4.427, P=0.024). The restricted cubic spline plot showed a linear dose-response relationship between RDW levels and the risk of cardiovascular events (P＜0.001, Pnonlinea r=0.853).  Conclusion   RDW and hsCRP levels have a significant interaction on cardiovascular events, and the coexistence of high RDW and high hsCRP significantly increases the risk of cardiovascular events in MHD patients. 

Key words: Hemodialysis, Red blood cell distribution width, High-sensitivity C-reactive protein, Cardiovascular events