EFFECTIVENESS OF PULMONARY REHABILITATION ON EXERCISE TOLERANCE IN PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND CARDIAC COMORBIDITIES

Background: Chronic Obstructive Pulmonary Disease (COPD) often coexists with cardiovascular disease (CVD), compounding limitations in physical function and quality of life. While pulmonary rehabilitation (PR) is well-established for improving outcomes in COPD, evidence regarding its efficacy in patients with concurrent cardiac comorbidities remains limited. Objective: To assess the effectiveness of pulmonary rehabilitation in improving exercise tolerance among COPD patients with coexisting cardiac conditions. Methods: A randomized controlled trial was conducted over 12 months at tertiary hospitals in Pakistan. A total of 110 stable COPD patients with cardiac comorbidities were randomized equally into intervention and control groups. The intervention group received an 8-week structured PR program in addition to standard care, while the control group received standard care alone. Primary outcome was change in six-minute walk distance (6MWD). Secondary outcomes included Modified Medical Research Council (mMRC) dyspnea scale, COPD Assessment Test (CAT), and St. George’s Respiratory Questionnaire (SGRQ). Data were analyzed using paired and independent t-tests, with p < 0.05 considered statistically significant. Results: The intervention group showed a significant mean increase in 6MWD (63.2 m, p < 0.001), while the control group had a non-significant change (6.5 m, p = 0.186). mMRC and CAT scores significantly improved in the intervention group (p < 0.001), with negligible changes in controls. SGRQ total scores decreased by 12.8 points in the intervention group (p < 0.001), indicating better quality of life. No adverse events were reported. Conclusion: Pulmonary rehabilitation significantly enhances exercise capacity and symptom burden in COPD patients with cardiac comorbidities. These findings support integrating PR into routine care for this high-risk group.