Neutrophil Percentage-to-Albumin Ratio as a Prognostic Marker in Pneumonia Patients Aged 80 and Above in Intensive...

Background/Objectives: In recent years, inflammatory markers have been increasingly utilized to predict disease prognosis. The neutrophil percentage-to-albumin ratio (NPAR) has emerged as a novel biomarker reflecting inflammation and systemic response. This study was conducted to evaluate the prognostic value of NPAR in pneumonia patients aged 80 years and older hospitalized in intensive care. Methods: Patients aged 80 years and older who were followed up in the intensive care unit with a diagnosis of pneumonia between 1 October 2022, and 31 May 2024, were retrospectively reviewed. Demographic characteristics, laboratory data, disease severity scores (APACHE II, SOFA), intensive care interventions, and variables associated with mortality were analyzed. NPAR was calculated by dividing the neutrophil percentage by the serum albumin level. The prognostic value of NPAR was assessed using Kaplan-Meier survival analysis, receiver operating characteristic (ROC) curve analysis, and Cox regression analysis. Results: A total of 135 patients were included in the study. Patients with NPAR > 0.286 had significantly higher SOFA (p = 0.002) and APACHE II (p = 0.007) scores. The high NPAR group was at significantly greater risk for requiring invasive mechanical ventilation (p = 0.003), vasopressor support (p = 0.042), and developing sepsis (p = 0.035). Elevated NPAR was strongly associated with mortality (p < 0.001) and was identified as an independent predictor of mortality in the Cox regression analysis (HR = 2.488, 95% CI: 1.167-5.302, p = 0.018). Conclusions: NPAR may serve as an effective biomarker for predicting disease severity and mortality risk in pneumonia patients aged 80 years and older. Due to its simplicity and accessibility, it can be considered a practical parameter for integration into clinical practice. However, large-scale, multicenter, and prospective studies are needed to validate these findings.