Does Increased Body Mass Index Effect the Gains of Pulmonary Rehabilitation in Chronic Obstructive Pulmonary Disease Patients?

Objective: We aimed to compare the gain of pulmonary rehabilitation (PR) in obese, pre-obese, and normal-weight patients with chronic obstructive pulmonary disease (COPD) who underwent a PR program.

Methods: COPD patients (n=137) underwent pulmonary and cardiac system examination and pulmonary function tests (PFTs) before PR. Chest X-rays, arterial blood gases, body mass index, quality of life (QOL) questionnaires, anxiety and depression scores, and Modified Medical Research Council dyspnea scale (MMRC) scores were evaluated in all patients. A 6-min walk test was performed to determine the exercise capacity of the patients. All patients underwent an 8-week outpatient PR program. The patients were reevaluated at the end of 8th week in terms of all parameters.

Results: The study group consisted of 44 normal-weight, 52 pre-obese, and 41 obese COPD patients. Before PR, there was no significant difference in terms of 6-min walk distance (6MWD), PFT, MMRC, or QOL scores between the groups (p>0.05 for all). After PR, partial arterial oxygen pressure and arterial saturation, MMRC, and QOL scores improved significantly in all three groups (p<0.05 for all). 6MWD and walkwork significantly increased after PR in all three groups (p<0.001 for all), but the gain in 6MWD was significantly lower in obese patients compared to pre-obese and normal-weight patients (p=0.049).

Conclusion: Pre-obese and obese patients benefit from PR similarly to the normal-weight patients in terms of gas exchange, dyspnea perception, and QOL. But it seems to be that exercise capacity improves less in obese COPD patients compared to pre-obese and normal-weight patients.