Effects of an outpatient service rehabilitation programme in patients affected by pulmonary arterial hypertension: an observational study

Background: Pulmonary arterial hypertension (PAH) is a rare disease characterised by a severe impairment of functional status and quality of life (QoL). Use of rehabilitative programmes may help to improve outcomes. The aim of this pre/post test case series was to evaluate the impact of a training program, including sessions of aerobic and resistance exercise, inspiratory muscle reinforcement, slow breathing, relaxation, and psychological support, on functional outcomes. Methods: Fifteen patients affected by PAH, in World Health Organization (WHO) Functional Class (FC) II or III and in stable clinical condition, were included in a 4-week cardiorespiratory training programme conducted in outpatient service. Patients were tested during a routine control visit (T0), one month later at the beginning of the training programme (T1), and at study end (T2). Between T0 and T1, patients continued their normal activities and therapies. At each step, patients underwent respiratory and functional evaluation by spirometry, 6-minute walk test (6-MWT), maximal cardiopulmonary exercise testing (CPET), echocardiography, and levels of brain natriuretic peptide (BNP). QoL was also assessed at T1 and T2 using the Hospital Anxiety and Depression Scale and the EuroQoL-5D questionnaire. The primary endpoint was the effect of training on peak oxygen consumption (peak VO2). Results: There were no significant differences in BNP levels, or in any of the respiratory or echocardiographic parameters measured, between T0 and T1. Between T1 and T2, significant improvements were recorded in QoL (HADS-Anxiety mean change 3.5 ± 3.3 and HADS-Depression mean change 1.6 ± 2.0, all p < 0.01). Significant improvements were also observed in functional capacity with distance walked at 6-MWT increasing from 455 ± 115 to 487 ± 120 (+8%, p < 0.01), workload (WR) of CPET was increased from 22% (from 73 ± 22 to 87 ± 21 watt, p < 0.001), peak VO2 increasing from 17.3 ± 4.2 to 19.9 ± 4.5 mL/kg/min (p < 0.001) and pulse O2 increasing from 7.8 ± 1.8 to 8.8 ± 2.4 mL/beat (p < 0.01). No adverse events or deterioration in clinical status were observed during the training sessions. Conclusion: Cardiorespiratory training in a outpatient service is a suitable option for patients with PAH in WHO FC II/III thanks to improved exercise capacity and QoL, which may allow them to achieve better outcomes.