A systematic review of clinical trial data showed that exercise training improves exercise capacity and the quality of life in patients with pulmonary arterial hypertension (PAH). The study concluded that exercise training should, like medications, be a recommended treatment for PAH.
The study, “Effects of Exercise Training on Exercise Capacity in Pulmonary Arterial Hypertension: A Systematic Review of Clinical Trials,“ investigated exercise data from studies in PAH patients. The research team from Manipal University, India, reviewed 15 studies published between Jan. 1, 1980, and March 31, 2015, including a total of 482 patients. The patients were classified as having WHO functional class II-IV PAH.
Researchers analyzed the quality of the studies using a well-known quality index, and four studies were rated to be of good, six of moderate, and five of poor quality. Most studies used a combination of aerobic and resistance training, including interval bicycle ergometry, walking, strength training, respiratory muscle training, and yoga. The intensity of the bicycle training was guided using percentages of peak workload, oxygen consumption, or maximum heart rate. All the programs, running between six and 15 weeks, were supervised.
The findings, published in the journal Heart, Lung and Circulation, showed that participants’ capacity in the six-minute walk distance (6MWD) increased between 17 and 96 meters. Peak oxygen consumption, ventilatory efficiency, and other exercise testing variables also showed improvement. While some studies reported that patients improved on average by one functional class, others did not observe functional class changes. Survival rates at one, two, and three years for patients in exercise programs have been reported to be in the range of 73 percent to 100 percent.
Improvements in 6MWD varied with the type of training used, but generally studies using a combination of aerobic-resistance and respiratory muscle training showed the largest improvements in 6MWD. Resistance and endurance training for the lower limbs did not produce equally positive results.
Nevertheless, all studies reported improvements in quality of life measurements. Additionally, exercise training resulted in beneficial changes in pulmonary artery parameters measured by echocardiography and magnetic resonance imaging (MRI).
In their conclusion, the authors noted that exercise training appears to be a suitable intervention for PAH patients, but the studies themselves often lacked in methodology and quality of design. Long-term, large clinical trials are needed to strengthen evidence of exercise benefits for PAH patients, and to determine which types of exercise and intensity levels are most beneficial.