Association of Serum Lactate Dehydrogenase to Albumin Ratio with the Risk of Stroke Associated Pneumonia in Acute Stroke Patients

Abstract

Introduction: Stroke-associated pneumonia (SAP) is a frequent complication of acute stroke and contributes to increased morbidity, mortality, intensive care requirement, and prolonged hospitalization. The lactate dehydrogenase-to-albumin ratio (LAR) combines markers of cellular injury and systemic inflammatory or nutritional status and may provide a simple indicator for early SAP risk stratification.

Aim & Objective: To determine the association between serum LAR and SAP in acute stroke patients, assess its diagnostic ability for predicting SAP, and evaluate clinical outcomes according to different LAR levels.

Materials & Methods: This cross-sectional observational study was conducted in the Department of General Medicine, SRN Hospital, M.L.N. Medical College, Prayagraj, from March 2025 to March 2026. One hundred consecutive adults with acute ischemic or hemorrhagic stroke presenting within seven days were enrolled. Serum LDH and albumin were measured, LAR was calculated, and SAP was diagnosed using modified CDC criteria. Statistical analysis included t-test, chi-square test, Pearson correlation, multivariate logistic regression, and ROC analysis.  

Results: SAP occurred in 26% of patients. Mean LAR was significantly higher in SAP than non-SAP patients (33.65 ± 9.22 vs 19.04 ± 6.33, p<0.001). LAR showed strong predictive performance with an AUC of 0.897 and an optimal cutoff of 24.24, providing 84.6% sensitivity, 83.8% specificity, 64.7% positive predictive value, 93.9% negative predictive value, and 84% overall accuracy. Higher NIHSS, dysphagia, mechanical ventilation, and LAR independently predicted SAP. SAP was associated with higher ICU admission and mortality.

Conclusion: LAR was significantly associated with SAP and remained an independent predictor after adjustment. It may serve as a simple, inexpensive biomarker for early identification of high-risk acute stroke patients in routine clinical stroke care.

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