# Association of inflammatory markers and surgical intervention with postoperative pneumonia in patients with femoral intertrochanteric fracture: A propensity score-matched cohort study

## TL;DR

This study finds that higher postoperative neutrophil-to-lymphocyte ratio (NLR) is linked to increased risk of pneumonia after hip fracture surgery.

## Contribution

The study identifies postoperative NLR as an independent predictor of postoperative pneumonia in patients with femoral intertrochanteric fractures.

## Key findings

- 53 out of 335 patients (15.8%) developed postoperative pneumonia.
- Postoperative NLR had an area under the ROC curve of 0.8396, indicating strong predictive power.
- Propensity score matching confirmed that NLR was significantly higher in patients who developed pneumonia.

## Abstract

This study was conducted to determine the value of inflammatory markers and surgical intervention for predicting the occurrence of postoperative pneumonia (POP) in patients undergoing proximal femoral nail antirotation (PFNA) surgery for femoral intertrochanteric fracture (FIF).

A retrospective cohort analysis was conducted on patients with FIF who underwent PFNA surgery at The First People's Hospital of Jiande from January 2021 to December 2024. Systematically documented variables included preoperative and postoperative inflammatory biomarker levels, demographic characteristics, surgical approach and duration, and postoperative outcomes. The prognostic capacity of inflammatory markers for predicting POP was evaluated through a propensity score-matched comparative analysis framework.

Among 335 patients, 53 (15.8 %) had POP. After matching, 193 patients (POP group: n = 49; non-POP group: n = 144) were included in the analysis. The median (25th percentile, 75th percentile) postoperative systemic immune–inflammation index and neutrophil-to-lymphocyte ratio (NLR) were significantly higher in the POP group than in the non-POP group (1832.00 [1388.00, 3369.67] vs. 1261.76 [936.44, 1893.94], respectively P < 0.001, and 13.43 [10.85, 16.67] vs. 7.89 [5.32, 11.00], respectively, P < 0.001). Multivariate analysis showed that postoperative NLR was an independent predictor of POP (area under the receiver operating characteristic curve 0.8396, P < 0.001).

Postoperative NLR may predict POP among patients undergoing PFNA surgery for FIF. However, the clinical utility and optimal thresholds require validation in future prospective studies.