Weight of evidence supports exercise training in PAH
medwireNews: Exercise training is a “promising intervention”, alongside medical treatment, in patients with pulmonary arterial hypertension (PAH), say the authors of a systematic review.
However, they also highlight the need for more research. The team identified 15 studies of exercise training, involving 482 PAH patients, but the study designs were very variable, preventing them from doing a meta-analysis of the data.
The studies comprised four randomised trials, eight non-randomised trials and three case series/reports. Abraham Samuel Babu (Manipal University, India) and co-authors rated five of these studies as good quality, eight as moderate quality and four as poor.
Overall, exercise training improved patients’ 6-minute walk distance (6MWD), with reported increases ranging from 17 to 96 metres. Patients also achieved improvements in other exercise variables, including peak VO2, which increased to between 1.1 and 2.1 mL/kg per min.
However, the researchers note that peak VO2 remained below 3.5 mL/kg per min (typical for untrained, healthy men), despite the generally large improvements in 6MWD.
“The wide variation in improvements in 6MWD brings to light the need for establishing the minimal clinically important difference […] for the 6MWT in PAH”, they write in Heart, Lung and Circulation.
Exercise training improved patients’ functional class – significantly in some studies with a positive trend in others – which the team describes as “encouraging”, given that improvements in functional class have been associated with lower 3-year mortality.
The studies in the systematic review all reported high survival rates for patients participating in exercise training, although the authors caution that research into the survival benefits of exercise training “is in its early stages”.
All studies reported that exercise training led to significant improvements in patients’ quality of life.
Babu et al stress that more research is needed to determine the optimal intensity and duration of exercise training, and its effects on outcomes including cardiac function and survival. But they believe that the evidence identified in their review “supports the argument on the potential benefits for exercise training as an adjunct to existing medical therapies.”
medwireNews is an independent medical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2016