Home Training Program Improves Outcomes in Patients With PAH

Findings from an interventional pilot study on patients with pulmonary arterial hypertension (PAH) indicated that 6 months of home physical and respiratory rehabilitation training significantly improved the 6-minute walk test (6MWT) distance by 71.38 ± 83.4 meters after 6 months (P =.004), with improvements lasting at least 12 months (P =.043). Patients also retained respiratory muscle strength after 12 months (P <.01).

Additionally, the patients self-reported significant improvement in quality of life via the 36-Item Short Form Health Survey (SF-36); however, this measure did not persist following completion of the study.

Adherence to home exercise protocols on average during the 6-month compulsory intervention phase was 91.88 ±  14.1%, whereas patient adherence to the program almost completely ceased during the 6-month observation phase following program completion.

Clinical Relevance

The primary outcomes of PAH therapy attempt to improve quality of life in the early stages of the disease to reduce disease progression and alter the typically poor patient prognosis. The authors suggest that a home-based rehabilitation program “offers hope for physiotherapeutic care for patients with PAH who do not have access to other forms of rehabilitation.” They state that the “results of our study prove that the home-based exercise program…is safe, effective, and acceptable to patients with PAH, which encourages its implementation in centers which do not provide inpatient or outpatient rehabilitation.”

Study Methods

The investigators enrolled 46 patients with PAH from the Cardiology Outpatient Clinic and the Department of Cardiology of the University Hospital in Bialystok, Poland. Results from 7 of these patients were incomplete. The control group consisted of 25 individuals without any cardiovascular, respiratory, or chronic diseases. The researchers used the control group mainly as a reference for norms of body composition, handgrip strength, and respiratory muscle strength.

Researchers performed evaluations at baseline, after the 6-month training program ended, and 6 months later to track carry-over results and patient adherence to the program. Measurements included blood pressure and heart rate pre- and post-treadmill test and 6-MWT. During the treadmill test, researchers assessed peak oxygen consumption (VO₂ Max), exercise ventilatory efficiency, and anaerobic threshold. Following the 6-MWT, researchers used the 10-point Borg Scale to assess dyspnea and fatigue. Before, during, and following the 6-MWT, they measured blood oxygen saturation with pulse oximetry.

The investigators collected strength measurements including handgrip strength using dynamometry, and respiratory muscle strength using the MicroRPM Respiratory Pressure Meter, which measures maximum inspiratory and expiratory pressures during forced inhalation and exhalation. Lastly, the patients had their body composition measured using bioelectrical impedance.

Therapists at the Department of Rehabilitation instructed the patients on proper exercise technique and the overall structure of the exercise program, as well as when to stop exercise, how to manage adverse reactions during and following the routine, or any contraindications to initiating the routine. Therapists also trained patients on self-monitoring techniques to report heart rate, blood pressure, dyspnea and fatigue, duration of the training session, step count during the training session using a pedometer, total number of steps each day, and any adverse responses or change in symptoms that may have affected exercise or were unassociated with exercise.

The training consisted of a 5-to 10-minute warm-up, 15 exercises of all body parts, including inspiratory respiratory muscle strengthening, and aerobic training using interval marching training with 2 minutes of marching interrupted by 1 of 5 respiratory exercises performed in a particular order. Lastly, patients performed a 5- to 15-minute cool down to prevent a sudden drop in vitals.

Patients performed exercise training and respiratory exercises once a day for a minimum of 5 days a week for 6 months. The intensity of effort was set at 4-5 out of 10 on the Borg Scale at the level of 60-70% heart rate reserve. The duration of each exercise session was 45 to 60 minutes and no less than 30 minutes a day.

Adverse Responses

One patient reported excessive fatigue and another reported a sudden increase in heart rate during the exercise which provoked anxiety as the only adverse responses. All other adverse events were unrelated to the exercise program.

Study Limitations

Limitations of the study included small sample size, the model of self-reported monitoring adherence to the therapy program instead of telemonitoring, and lack of a 12-month evaluation of the control group due to COVID-19 pandemic restrictions, which made a comparison between the PAH group and the control group at 12 months impossible.

Reference

Wojciuk M, Ciolkiewicz M, Kuryliszyn-Moskal A, et al. Effectiveness and safety of a simple home-based rehabilitation program in pulmonary arterial hypertension: an interventional pilot study. 2021;13(1):79. BMC Sports Sci Med Rehabil. doi:10.1186/s13102-021-00315-y