Association between neutrophil-lymphocyte ratio and all-cause and cardiovascular mortality in osteoarthritis patients from the NHANES 1999–2018 cohort

This cross-sectional study aimed to investigate the correlation between the neutrophil-lymphocyte ratio (NLR) and all-cause mortality and cardiovascular mortality in osteoarthritis (OA) patients. We involved 3549 adults with OA from the National Health and Nutrition Examination Survey (NHANES) database (1999-2018). The optimal NLR threshold (2.53) was determined using maximally selected rank statistics. Kaplan-Meier (KM), weighted Cox regression, and restricted cubic spline (RCS) analyses were employed to assess the relationship between the NLR and mortality outcomes, with subgroup and sensitivity analyses evaluating the stability of the observed associations. Time-dependent receiver operating characteristic (ROC) curve analysis was conducted to evaluate the NLR prognostic accuracy for mortality across time points. During the 91-month median follow-up period, 843 patients died (256 from cardiovascular disease). Elevated NLR (≥ 2.53) was associated with increased risks of all-cause mortality (HR = 1.82) and cardiovascular mortality (HR = 2.50). Nonlinear correlations of the NLR with mortality outcomes were observed. ROC analysis demonstrated superior NLR predictive capability for all-cause and cardiovascular mortality compared to individual blood cell types. Elevated NLR is independently associated with increased risks of all-cause mortality and cardiovascular mortality in OA patients.