Pulmonary rehabilitation and endothelial function in patients with chronic obstructive pulmonary disease: A prospective cohort study

Abstract

BackgroundChronic obstructive pulmonary disease (COPD) is associated with subclinical atherosclerosis and endothelial dysfunction, thereby leading to increased cardiovascular risk. In the present study, we evaluated the changes in endothelium-dependent flow-mediated dilation (FMD) in a cohort of severe COPD patients undergoing pulmonary rehabilitation. MethodsConsecutive COPD patients referred to our Pulmonary Rehabilitation Unit were screened for inclusion. All study procedures were performed at hospital admission and discharge. ResultsOf 78 patients screened for eligibility, a total of 40 participants (67.5% males, median age 72.5 years) were included. After pulmonary rehabilitation, a significant improvement in functional parameters, exercise capacity, and measures of disability and quality of life were documented. FMD changed from 3.25% (IQR: 2.31–4.26) to 4.95% (IQR: 3.57–6.02), corresponding to a 52.3% increase of its median value (P < 0.001). Significantly lower changes in FMD were documented in COPD patients with hypercholesterolemia as compared to those without (+0.33% ± 1.61 vs. +1.62% ± 1.59, P = 0.037). Changes in FMD (ΔFMD) were positively associated with changes in forced expiratory volume in 1 s (FEV1), when expressed both as absolute values (ΔFEV1) (r = 0.503, P = 0.002) and as percentages of predicted values (ΔFEV1%) (r = 0.608; P < 0.001). In multiple linear regressions, after adjusting for major cardiovascular risk factors, ΔFEV1 (β=0.342; P = 0.049) and ΔFEV1% (β=0.480; P = 0.015) were both confirmed as independent predictors of ΔFMD. ConclusionsResults of our study suggest that endothelial function may improve in COPD after pulmonary rehabilitation. The potential beneficial effect in terms of cardiovascular risk prevention should be evaluated in ad hoc designed studies.