# Neutrophil percentage-to-albumin ratio is an independent risk factor for MACEs in patients with acute coronary syndrome undergoing percutaneous coronary intervention

## TL;DR

A new blood marker called NPAR can predict heart problems in patients with heart attacks undergoing a common heart procedure.

## Contribution

NPAR is a novel composite biomarker that independently predicts major adverse cardiovascular events in acute coronary syndrome patients.

## Key findings

- NPAR levels were significantly higher in patients who experienced MACEs.
- NPAR ≥17.326 is an independent predictor of MACEs after adjusting for other risk factors.
- Higher NPAR values correlate with increased risk of adverse outcomes in a dose-dependent manner.

## Abstract

Neutrophils are well-established biomarkers of systemic inflammation, whereas serum albumin levels are commonly used as reliable indicators of nutritional status. The neutrophil percentage-to-albumin ratio (NPAR), a novel composite biomarker integrating inflammatory and nutritional parameters, has shown promising predictive value across a range of clinical settings. However, its association with outcomes in patients with acute coronary syndrome (ACS) remains unclear. This study aimed to evaluate the prognostic utility of NPAR for predicting major adverse cardiovascular events (MACEs) in patients with ACS.

From January 2016 to December 2018, 1553 consecutive patients with ACS undergoing percutaneous coronary intervention (PCI) were enrolled at the Affiliated Hospital of Chengde Medical University. The NPAR was calculated as the admission neutrophil percentage divided by serum albumin concentration. Serum albumin was measured in g/L and converted to g/dL (dividing by 10) for NPAR calculation to align with conventional units. The primary follow-up endpoints were MACEs, comprising all-cause mortality and heart failure readmission.

During follow-up, 1,524 patients completed the study; 55 of them experienced MACEs. The NPAR levels differed significantly between the MACE and non-MACE groups (P < 0.001). Receiver operating characteristic (ROC) analysis demonstrated an area under the curve (AUC) of 0.700 for the NPAR in predicting MACEs (95% CI: 0.635–0.766; P < 0.001), with an optimal cutoff value of 17.326 determined using the Youden index. Kaplan–Meier analysis revealed significantly lower cumulative event-free survival in the high NPAR group (≥17.326) compared to the low NPAR group (<17.326) [log-rank P < 0.001]. Multivariable Cox regression identified four independent predictors of MACEs: age ≥ 65 years [hazard ratio [HR]: 2.944, 95% confidence interval [CI]: 1.653–5.245, P < 0.001]; left ventricular ejection fraction <40% (HR: 6.114, 95% CI: 2.786–13.419, P < 0.001); serum creatinine > 110 μmol/L (HR: 3.768, 95% CI: 1.336–10.631, P = 0.012), and NPAR ≥ 17.326 (HR: 3.014, 95% CI: 1.418–6.405, P = 0.004). Restricted cubic spline analysis confirmed a positive dose-response relationship, showing progressively increased MACE risk with rising NPAR levels (P < 0.001).

NPAR ≥ 17.326 is an independent prognostic risk factor for patients with ACS undergoing PCI and may be a valuable clinical marker for identifying high-risk patients.

Graphical summary.

Graphical summary.