High-intensity non-invasive ventilation during exercise-training versus without in people with very severe COPD and chronic hypercapnic respiratory failure: a randomised controlled trial.

BACKGROUND: People with very severe chronic obstructive pulmonary disease (COPD) using nocturnal non-invasive ventilation (NIV) for chronic hypercapnic respiratory failure (CHRF) experience reduced exercise capacity and severe dyspnoea during exercise training (ET). The use of NIV during ET can personalise training during pulmonary rehabilitation (PR) but whether high-intensity NIV (HI-NIV) during exercise is accepted and improves outcomes in these extremely physically limited patients is unknown. The aim of this trial was to determine if ET with HI-NIV during PR was more effective than without at improving exercise capacity and reducing dyspnoea during exercise. METHODS: Patients with COPD, CHRF and nocturnal-NIV were randomised to supervised cycle-ET as part of PR with HI-NIV or without (control). Primary outcome was change in cycle endurance time (ΔCETtime), while secondary outcomes were dyspnoea at isotime during the cycle endurance test and during ET-sessions and for the HI-NIV group, post-trial preferred exercising method. RESULTS: Twenty-six participants (forced expiratory volume in 1 s 22±7%pred, PaCO251±7 mm Hg) completed the trial (HI-NIV: n=13, ET: IPAP 26±3/EPAP 6±1 cm H2O; control n=13). At completion of a 3 week ET-programme, no significant between-group differences in ΔCETtime were seen (HI-NIV-control: Δ105 s 95% CI (-92 to 302), p=0.608). Within-group ΔCETtime was significant (HI-NIV: +246 s 95% CI (61 to 432); control: +141 s 95% CI (60 to 222); all p<0.05). The number of responders (Δ>minimal important difference (MID)101 s: n=53.8%) was the same in both groups for absolute ΔCETtime and 69.2% of control and 76.9% of the HI-NIV group had a %change>MID33%.Compared with control, the HI-NIV group reported less isotime dyspnoea (Δ-2.0 pts. 95% CI (-3.2 to -0.8), p=0.005) and during ET (Δ-3.2 pts. 95% CI (-4.6 to -1.9), p<0.001). Most of the HI-NIV group (n=12/13) preferred exercising with NIV. CONCLUSION: In this small group of patients with very severe COPD requiring nocturnal NIV, participation in an ET-programme during PR significantly improved exercise capacity irrespective of HI-NIV use. Reported dyspnoea was in favour of HI-NIV. TRIAL REGISTRATION NUMBER: NCT03803358.

Pulmonary Rehabilitation and Exercise Training in Chronic Obstructive Pulmonary Disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a common condition that is becoming increasingly prevalent. It affects 13.2% of the population over age 40 in Germany. In 2020, it will be the third most common cause of morbidity and mortality around the world. It markedly impairs the quality of life of those who suffer from it and presents a major economic challenge to the health-care system. METHODS: This review is based on pertinent publications retrieved by a selective literature search and on the authors' clinical experience. RESULTS: Pulmonary rehabilitation (PR) for patients with COPD is supported by evidence on the highest level. It is associated with statistically significant (p <0.001) and clinically relevant improvement in physical performance (6-minute walk distance: + 44 m; 95% confidence interval [33; 55]), shortness of breath (Chronic Respiratory Disease Questionnaire: +0.79 points [0.56; 1.03]), and the quality of life (Saint George´s Respiratory Questionnaire: -6.9 points [-9.3; -4.5]). The benefits of PR are especially evident after an acute exacerbation of COPD: it significantly lowers the rate of readmission to the hospital (odds ratio 0.22 [0.08; 0.58], p = 0.002) and improves physical performance ability (6-minute walk distance: + 62 m [38; 86] and the quality of life (Saint George´s Respiratory Questionnaire: -7.8 points [-12.1; -3.5]; p <0.001 for both). CONCLUSION: PR is an effective and cost-effective therapeutic intervention that improves physical performance ability, shortness of breath, and the quality of life in patients with COPD, but it has not yet been fully implemented as recommended in the relevant guidelines. There is a need for targeted, problem-oriented referral to a range of PR programs with problem-specific content. The necessary outpatient PR structures still need to be established in Germany.