Exercise training improves physical fitness in patients with pulmonary arterial hypertension: a systematic review and meta-analysis of controlled trials

Background: Pulmonary arterial hypertension (PAH) is a progressive disorder characterized by hypertension in the pulmonary arteries. PAH leads to symptoms such as shortness of breath, dizziness, leg edema and chest pain, impacting heavily on quality of life. The aim of this systematic review and meta-analysis was to determine the effect of exercise training to improve physical fitness and functionality in patients with PAH. Methods: A search was conducted for controlled trials using the databases Medline, Embase, SPORT Discus and Cochrane Central Register of Controlled Trials. Studies were included if at least 80% of the participants presented with group 1 PAH and if the intervention consisted of an exercise training program of at least 3 weeks duration. Data were extracted on study quality, participant and exercise intervention characteristics, and outcomes. Data were pooled by the generic inverse variance method using random effect models and were expressed as weighted means and 95% confidence intervals (CI). Results: Of 110 identified abstracts, 5 studies with 106 patients (exercise: 53; control: 53; mean age 49.7 years) were included. Disease severity ranged from mild to severe; 96 patients suffered from PAH, 10 patients had chronic thromboembolic pulmonary hypertension. Exercise training led to an increase in 6 minute walk distance (72.5 m; 95% CI 46.0 m to 99.1 m; p < 0.0001) and peak oxygen uptake (2.16 mL/kg/min; 95% CI 2.16 to 3.93; p = 0.02). No severe adverse events during exercise were reported. Conclusions: Our findings suggest that an exercise training program positively influences exercise tolerance and functional capacity in patients with PAH.