Association of the neutrophil-to-lymphocyte ratio with sudden cardiac death in the patients with diabetic foot ulcer

Yi Chen^1,2Junyan Zhao¹Yuchen Sun¹Zhongjing Yang¹Caizhe Yang¹Di Zhu^1*

• ¹People's Liberation Army Air Force Special Medical Center, Beijing, China
• ²China Medical University, Shenyang, China

Aims This study aims to investigate the relationship between the neutrophil-to-lymphocyte (NLR) and the risk of sudden cardiac death (SCD) in the patients with diabetic foot ulcer (DFU). Methods A retrospective study enrolled 688 patients with DFU who were admitted to Air Force Medical Center between January 2010 and December 2023. To control for potential confounding effects, a 1:1 propensity score matching (PSM) method was applied. The relationship between NLR and SCD risk was analyzed using the Kaplan-Meier (K-M) survival curve analysis, multivariate Cox proportional hazard regression model, Restricted cubic spline (RCS) model analysis and subgroup analyses. Results Over a median follow-up period of 61 months , 38 cases of SCD were documented. Based on median NLR, participants were stratified into higher (<4.22) and lower (≥4.22) NLR groups. Cox proportional hazard model revealed that individuals with higher NLR was independently associated with the increased risk of SCD ( HR: 10.67, 95% CI: 3.61 ~ 31.53, P<0.001). RCS model showed that SCD risk was non-linearly correlated with gradual increases in NLR levels. Subgroup analyses confirmed the stability of the results. Conclusions Elevated NLR independently confers an increased risk for SCD in individuals with DFU.