Chronic obstructive pulmonary disease (COPD) is a major global health problem associated with significant morbidity and mortality. Acute exacerbations of COPD (AECOPD) are often accompanied by cardiovascular stress, and biomarkers like brain natriuretic peptide (BNP) may help in assessing disease severity and cardiac involvement. Aim and Objectives: To evaluate plasma BNP levels in patients with AECOPD and to assess their correlation with disease severity, symptom burden, and clinical outcomes. Methodology: This prospective observational study was conducted at a tertiary care hospital from June 2024 to June 2025. A total of 110 patients with AECOPD were included. Ethical clearance was obtained, and informed consent was taken. Clinical evaluation, laboratory investigations, and spirometric assessment were performed. BNP levels were measured at admission. COPD severity was classified according to Global Initiative for Chronic Obstructive Lung Disease (GOLD) staging and Modified Medical Research Council (MMRC) grading. Results: The mean age of patients was 62.42±10.79 years, with a male predominance (81.8%). Smoking was present in 75% of patients. The mean BNP level was 121.31±48.29 pg/ml. BNP levels increased significantly with higher GOLD stages (r=0.786, p<0.01) and MMRC grades (r=0.486, p<0.01). Higher BNP levels were associated with increased disease severity and symptom burden. Conclusion: BNP levels are significantly elevated in AECOPD and correlate with disease severity and symptom grading. BNP can serve as a valuable biomarker for assessing severity and identifying cardiac involvement in COPD patients.

COPD, acute exacerbation, BNP, GOLD staging, MMRC grading, cardiac involvement