Active Cycle of Breathing Technique and Pursed Lip Breathing in Moderate to Severe COPD Patients

Abstract

Background: Chronic obstructive pulmonary disease (COPD) is associated with persistent airflow limitation, dyspnea, respiratory symptoms, and impaired health-related quality of life. Simple breathing interventions may provide accessible components of pulmonary rehabilitation, but direct comparative evidence between Active Cycle of Breathing Technique (ACBT) and Pursed Lip Breathing (PLB) remains limited. Objective: To compare the effects of ACBT plus diaphragmatic breathing with PLB plus diaphragmatic breathing on pulmonary function, oxygen saturation, dyspnea, respiratory symptom burden, and health-related quality of life in patients with moderate-to-severe COPD. Methods: This randomized clinical trial included 40 participants recruited by convenience sampling and randomly allocated to ACBT (n = 20) or PLB (n = 20). Both groups received diaphragmatic breathing and performed 15–20-minute sessions twice daily for eight weeks. Outcomes included FEV₁, FVC, SpO₂, mMRC, BCSS, and SGRQ. Results: FEV₁ increased by 0.21 L with ACBT and 0.14 L with PLB (between-group p < 0.001), while FVC increased by 0.28 L and 0.18 L, respectively (p < 0.01). mMRC decreased by 1.0 versus 0.5 points (p < 0.001), BCSS by 3.1 versus 2.0 points (p < 0.001), and SGRQ by 10.0 versus 7.95 points (p < 0.01). Post-intervention SpO₂ was 94% in both groups, with no significant between-group difference (p = 0.32). Conclusion: Both interventions improved the reported outcomes, while ACBT produced greater short-term improvements in pulmonary function, dyspnea, symptom burden, and quality-of-life measures. No comparative advantage was demonstrated for resting oxygen saturation.