Mortality in Advanced Chronic Obstructive Pulmonary Disease and Heart Failure Following Cardiopulmonary Rehabilitation

Abstract

Cardiopulmonary rehabilitation (CR) improves physical function and quality of life (QoL) in chronic obstructive pulmonary disease (COPD) and heart failure (HF), but it is unknown if CR improves outcomes in very severe disease. This study's purpose was to describe functional capacity (6-min walk distance [6MWD], steps/day), symptoms (dyspnea, depression), QoL (Short-Form Health Survey-Veterans [SF-36 V]) and cardiopulmonary function ( N-terminal pro-brain natriuretic peptide [NT-proBNP], forced expiratory volume in 1 s [FEV₁]), and derive predictors of mortality among patients with severe COPD and HF who participated in CR.

Methods and results: In this secondary analysis of a randomized controlled trial comparing two CR methods in severe COPD and HF, 90 (COPD = 63, HF = 27) male veterans, mean age 66 ± 9.24 years, 79% Caucasian, and body mass index 31 kg/m², were followed for 12 months after CR. The COPD group had greater functional decline than the HF group (6MWD, p = .006). Dyspnea was lower ( p = .001) and QoL higher ( p = .006) in the HF group. Mean NT-proBNP was higher in the HF group at all time points. FEV₁ improved over 12 months in both groups ( p = .01). Mortality was 8.9%, 16.7%, and 37.8% at 12, 24, and 60 months, respectively. One-year predictors of mortality were baseline total steps (<3,000/day), 6MWD (<229 meters), and NT-proBNP level (>2,000 mg/pg).

Conclusions: In very severe COPD and HF, risks of mortality over 12 months can predict patients unlikely to benefit from CR and should be considered at initial referral.

Keywords: COPD; cardiac rehabilitation; heart failure; mortality; pulmonary rehabilitation.