Pulmonary rehabilitation (PR) remains grossly underutilised by suitable patients worldwide. We investigated whether home-based maintenance tele-rehabilitation will be as effective as hospital-based maintenance rehabilitation and superior to usual care in reducing the risk for acute chronic obstructive pulmonary disease (COPD) exacerbations, hospitalisations and emergency department (ED) visits.Following completion of an initial 2-month PR programme this prospective, randomised controlled trial (between December 2013 and July 2015) compared 12 months of home-based maintenance tele-rehabilitation (n=47) with 12 months of hospital-based, outpatient, maintenance rehabilitation (n=50) and also to 12 months of usual care treatment (n=50) without initial PR.In a multivariate analysis during the 12-month follow-up, both home-based tele-rehabilitation and hospital-based PR remained independent predictors of a lower risk for 1) acute COPD exacerbation (incidence rate ratio (IRR) 0.517, 95% CI 0.389-0.687, and IRR 0.635, 95% CI 0.473-0.853), respectively, and 2) hospitalisations for acute COPD exacerbation (IRR 0.189, 95% CI 0.100-0.358, and IRR 0.375, 95% CI 0.207-0.681), respectively. However, only home-based maintenance tele-rehabilitation and not hospital-based, outpatient, maintenance PR was an independent predictor of ED visits (IRR 0.116, 95% CI 0.072-0.185).Home-based maintenance tele-rehabilitation is equally effective as hospital-based, outpatient, maintenance PR in reducing the risk for acute COPD exacerbation and hospitalisations. In addition, it encounters a lower risk for ED visits, thereby constituting a potentially effective alternative strategy to hospital-based, outpatient, maintenance PR.

INTRODUCTION Telehealth for COVID-19 patients is still limited. We aimed to assess the clinical effects of a home-based tele-rehabilitation exercise program following hospital discharge during the first lockdown in Greece, April to July 2020. METHODS A pre-and post-intervention design was applied in two stages. Firstly, patients were instructed to use a specially designed for COVID-19, e-book during four tele-health sessions. Afterwards, a 2-month home-based program consisted of self-practice exercise and one-hour supervised telerehabilitation exercise sessions every 10 days, was delivered. At baseline and at the end of the program, participants were interviewed about their physical, psychological status and quality of life (QoL) during the posthospitalization period. The IPAQ-Gr, the HADS and the SF-36 questionnaires were used, respectively, and the participants were functionally assessed via teleconferences, using the 60 sec Sit to Stand Test (60secSTS), the Short Physical Performance Battery (SPPB) and the 3 min Step Test (3MST). RESULTS Seventy-four patients, median age 52.5 (IQR: 43-61) years were included at the first stage. From those, only 22 patients, mean ± SD age 50.1 ± 13.2 years completed the 2-month exercise program. The training program was well tolerated by all 22 patients. The mean number of unsupervised exercise sessions was 18.4 ± 3.5. No adverse effects were observed either during initial and follow-up assessment via tele-communication or during home-exercise sessions. Training improved significantly (p<0.001) lower limb muscle performance ], anxiety [median (IQR) HADS: 9 (6-13) to 4.3 (3.2-9.6)], depression [median (IQR) HADS: 5 (3-8) to 1.8 (0.9-3.7)], QoL [mean ± SD SF-36pcs: 37.5 ± 10.3 to 52.1 ± 6, and mean ± SD SF-36mcs: 42.9 ± 11.6 to 45.5 ± 12.3]. CONCLUSIONS Tele-rehabilitation may be feasible and may improve physical and psychological status of COVID-19 patients after hospital discharge.

In chronic obstructive pulmonary disease (COPD), daily physical activity is reported to be adversely associated with the magnitude of exercise-induced dynamic hyperinflation and peripheral muscle weakness. There is limited evidence whether central hemodynamic, oxygen transport, and peripheral muscle oxygenation capacities also contribute to reduced daily physical activity. Nineteen patients with COPD (FEV1, 48 ± 14% predicted) underwent a treadmill walking test at a speed corresponding to the individual patient's mean walking intensity, captured by a triaxial accelerometer during a preceding 7-day period. During the indoor treadmill test, the individual patient mean walking intensity (range, 1.5 to 2.3 m/s2) was significantly correlated with changes from baseline in cardiac output recorded by impedance cardiography (range, 1.2 to 4.2 L/min; r = 0.73), systemic vascular conductance (range, 7.9 to 33.7 ml·min(-1)·mmHg(-1); r = 0.77), systemic oxygen delivery estimated from cardiac output and arterial pulse-oxymetry saturation (range, 0.15 to 0.99 L/min; r = 0.70), arterio-venous oxygen content difference calculated from oxygen uptake and cardiac output (range, 3.7 to 11.8 mlO2/100 ml; r = -0.73), and quadriceps muscle fractional oxygen saturation assessed by near-infrared spectrometry (range, -6 to 23%; r = 0.77). In addition, mean walking intensity significantly correlated with the quadriceps muscle force adjusted for body weight (range, 0.28 to 0.60; r = 0.74) and the ratio of minute ventilation over maximal voluntary ventilation (range, 38 to 89%, r = -0.58). In COPD, in addition to ventilatory limitations and peripheral muscle weakness, intensity of daily physical activity is associated with both central hemodynamic and peripheral muscle oxygenation capacities regulating the adequacy of matching peripheral muscle oxygen availability by systemic oxygen transport.