Association between neutrophil percentage-to-albumin ratio (NPAR) and long-term mortality in community-dwelling adults with chest pain: Evidence from US NHANES 2001-2018.

Objective: The neutrophil percentage-to-albumin ratio (NPAR) is a readily available biomarker with prognostic significance across various disease conditions. However, its role in predicting mortality among community patients with chest pain remains underexplored. This study examined NPAR's association with long-term mortality in adults with chest pain using NHANES 2001-2018 data.

Methods: We analyzed data from 6846 community-dwelling adults reporting chest pain. Cox proportional hazards regression models, restricted cubic spline (RCS) analysis, and Kaplan-Meier survival curves were employed to evaluate the relationship between NPAR and the risk of all-cause and cardiovascular mortality. Models were adjusted for demographic, clinical, and laboratory covariates.

Results: Participants were categorized into tertiles based on NPAR values: T1 (<13.0), T2 (13.0-15.0), and T3 (>15.0). Multivariable analysis revealed that the T3 cohort demonstrated significantly increased risks of all-cause mortality (HR 1.56, 95% CI 1.32-1.84, P<0.001) and cardiovascular mortality (HR 1.86, 95% CI 1.37-2.51, P<0.001) relative to T1. RCS analysis identified a J-shaped relationship between NPAR and mortality risk, with a significant inflection point at NPAR >13.5 (P for non-linearity <0.001). Incremental analysis showed that each unit increase in NPAR was associated with an 11% higher risk of all-cause mortality (HR 1.11, 95% CI 1.07-1.14, P<0.001) and a 14% increased risk of cardiovascular mortality (HR 1.14, 95% CI 1.08-1.20, P<0.001).

Conclusions: Elevated NPAR levels are independently associated with increased long-term mortality in adults with chest pain. These findings position NPAR as a promising prognostic biomarker in this patient population.