Prognostic Value of Neutrophil-to-Lymphocyte Ratio (NLR), Monocyte-to-Lymphocyte Ratio (MLR), and Platelet-to-Lymphocyte Ratio (PLR) in NIV Rates, ICU Admission, Intubation, and Mortality among Filipino COPD Patients

Abstract Purpose This study aimed to evaluate the prognostic value of the neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR) in predicting intensive care unit (ICU) admission, need for ventilatory support, and in-hospital mortality among Filipino patients hospitalized for acute exacerbation of chronic obstructive pulmonary disease (AECOPD). It also sought to determine optimal cutoff values for early risk stratification. Methods This retrospective observational cohort study included Filipino adults aged ≥ 40 years admitted for AECOPD between January 2020 and July 2025. NLR, MLR, and PLR were calculated from complete blood count results obtained within 24 hours of hospital admission. Receiver operating characteristic (ROC) curve analysis was performed to identify optimal cutoff values, and multivariate logistic regression was used to evaluate independent associations with clinical outcomes after adjustment for age, comorbidities, smoking status, and COPD severity. Results A total of 171 patients were included. Elevated NLR, MLR, and PLR were significantly associated with adverse clinical outcomes. NLR demonstrated the strongest association with in-hospital mortality (OR = 4.15, p  < 0.001) and ICU admission (OR = 3.67, p  = 0.001). ROC analysis identified an optimal NLR cutoff value of 4.31 for predicting ICU admission (Youden’s J = 0.476). After multivariable adjustment, elevated NLR remained an independent predictor of ICU admission, intubation, and in-hospital mortality. Conclusions Admission NLR is a simple, inexpensive, and independently predictive inflammatory marker for poor clinical outcomes among hospitalized Filipino patients with AECOPD. Routine assessment of NLR at hospital admission may aid early risk stratification and guide timely clinical management.