Prevalence of Alpha-1 Antitrypsin Deficiency Among Patients with Early-Onset Chronic Obstructive Pulmonary Disease

Open Access

Abstract

Background: Chronic Obstructive Pulmonary Disease (COPD) is a heterogeneous respiratory disorder in which genetic factors contribute significantly to disease susceptibility, particularly in early-onset cases. Alpha-1 antitrypsin deficiency (AATD), caused by mutations in the SERPINA1 gene, is an important but underdiagnosed cause of COPD. Limited data exist regarding its prevalence and clinical association in South Asian populations, especially in Bangladesh. Objective: This study aimed to determine the prevalence of AATD among patients with early-onset COPD and evaluate its association with disease severity. Methods & Materials: A descriptive cross-sectional study was conducted at the Department of Respiratory Medicine, NIDCH, Dhaka, from July to December 2025. A total of 80 early-onset COPD patients were enrolled. Data were collected using structured questionnaires and spirometric records. Serum alpha-1 antitrypsin levels were measured quantitatively using nephelometry. Participants with low serum AAT levels underwent confirmatory targeted genotyping for the PiS and PiZ alleles via real-time PCR. COPD severity was classified using GOLD criteria. Statistical analysis was performed using SPSS version 25.0. Results: AATD was identified in 12.5% of patients. PiMZ was the most common variant (6.25%), followed by PiSZ (3.75%) and PiZZ (2.5%). A significant association was observed between AATD status and COPD severity (p = 0.02), with 80% of AATD cases presenting in GOLD III and IV stages. Non-AATD cases were predominantly in milder stages. Conclusion: AATD is a notable contributor to early-onset COPD and is significantly associated with increased disease severity. Routine screening for SERPINA1 mutations may facilitate early diagnosis and improved clinical management in COPD patients.