Individualized home-based exercise program for idiopathic pulmonary arterial hypertension patients: a preliminary study

Background: Exercise-based rehabilitation has been proved as a beneficial additional non-pharmacological treatment in patients with stable pulmonary arterial hypertension (PAH). Majority of studies include hospital-based supervised programs. To improve patient accessibility to this important intervention and long-term effect the research on home-based programs is warranted. The purpose of our study was to evaluate the adherence, safety, training effects of 12-week individualized home-based exercise program in patients with idiopathic PAH. Methods: This was a prospective pilot uncontrolled interventional study. Six patients with iPAH confirmed by right-heart catheterization from the Latvian PAH registry were selected. A 12-week exercise program adaptable for each patient's functional state and home environment was created. The program included muscle strength training, respiratory, aerobic exercise and neuro-muscular relaxation techniques, self-control monitoring, weekly phone control and on-site re-assessment by physiotherapist were parts of the program to ensure both individualized adjustments and proper execution, and to maximize clinical safety. The primary outcome measures for training effects were exercise capacity, breathing pattern and quality of life, for adherence days of performance, for safety any event of alarm sign indicators during exercising, incomplete recovery, worsening of PH symptoms. Results: The results showed a rather high degree of adherence to the prescribed exercise regimen (in average 92.5%). No adverse events were observed during the course of the program. The results proved the importance of ensuring optimal self-control skills both for objective measures and subjective symptoms. The 6-minute walking test (6MWT) results show that the developed program significantly improves exercise capacity (mean improvement 39 +/- 17.5 m). In four participants (66.7%) the minimum clinically important difference (MCID) for 6MWT distance in PAH patients was observed (25-33 m). Significant improvement in chest excursions confirm changes in breathing pattern suggesting better engagement of diaphragm during breathing after the program. Results did not show signifi cant improvements in either SF-36 survey domain. However, half of the participants reached MCID (11%) after the program at the physical health subscales. Conclusion: The results of this preliminary study prove that the created individualized home-based exercise program is safe, easily followed and allows progression in exercise intensity and improves physical functional state in clinically stable iPAH patients. This study hypothesis supports the need for RCT to continue research and approve the results.