Elevated neutrophil percentage-to-albumin ratio predicts 1-year unfavorable clinical outcome in patients with acute ischemic stroke

Abstract

To evaluate the prognostic significance of neutrophil percentage-to-albumin ratio (NPAR) in predicting 1-year clinical outcomes following acute ischemic stroke (AIS). In this retrospective cohort study, we analyzed consecutive AIS patients admitted to the Department of Neurology at The First Hospital of Anhui University of Science and Technology between May 2021 and July 2022. Systematic follow-up at 12 months post-AIS onset was conducted through telephone or in-person interviews. Multivariable logistic regression models evaluated the association of NPAR (as a categorical variable based on tertiles) with poor functional outcome (modified Rankin Scale [mRS] ≥ 3). Receiver operating characteristic (ROC) curve, net reclassification improvement (NRI), and integrated discrimination improvement (IDI) analyses were uesed to assess the prognostic performance of NPAR on poor functional outcome. Cox proportional hazards regression analysis assessed stroke recurrence and all-cause mortality. Recurrence probabilities were estimated and compared using Kaplan-Meier estimator with the log-rank test. The final cohort comprised 267 patients (mean age 63.9 ± 11.9 years; 64.4% male). Stratified into tertiles by NPAR levels, significant intergroup differences were observed in total cholesterol ( p = 0.004), triglycerides ( p = 0.010), high-density lipoprotein cholesterol (HDL-C) ( p = 0.023), and globulin ( p = 0.011). Compared to the highest NPAR tertile, individuals in the lowest NPAR tertile exhibited reduced mortality ( p = 0.040), fewer poor functional outcome ( p < 0.001), and lower stroke recurrence ( p = 0.014). After full covariate adjustment, NPAR maintained independent predictive value for 1-year poor functional outcomes (adjusted OR 7.32, 95% CI 2.51–21.32; p < 0.001) and stroke recurrence (adjusted HR 4.55, 95% CI 1.43–14.15; p = 0.013), while showed no association with mortality (adjusted HR 5.98, 95% CI 0.72–30.99; p = 0.102). Adding NPAR to the base clinical model significantly improved risk discrimination ( AUC 0.836, 95% CI 0.775–0.897; NRI 0.223, 95% CI 0.112–0.334, p < 0.001; IDI 0.099, 95% CI: 0.050–0.147, p < 0.001). Moreover, Kaplan-Meier curves confirmed higher recurrence in elevated NPAR strata (log-rank p = 0.010). Elevated NPAR independently predicts 1-year functional disability and stroke recurrence in AIS patients, but does not demonstrate mortality prognostic utility. These findings may position NPAR as a potential biomarker for risk-stratified secondary prevention strategies.