Pulmonary Rehabilitation and its effects on COVID-19: A systematic review on the effects of Pulmonary Rehabilitation on survivors of COVID-19 in the post-hospitalization phase

Background: COVID-19 severely impairs lung function and can damage the lung tissue. Pulmonary rehabilitation (PR) is effective in restoring exercise capacity and lung function of damaged lungs. Many people will need rehabilitation after contracting COVID-19. Objective: This systematic review aimed to assess the effects of PR on pulmonary function, exercise capacity and health-related quality of life (HrQoL). Methods: A PRISMA guided systematic review was conducted in seven databases and four trial registers. The inclusion criteria included the following: 1) a population of COVID-19 survivors in the post-hospitalization or long-term phase, 2) a PR intervention was applied, 3) a comparison between an intervention and control group after a minimum one month follow-up. Studies were included if they met all of the inclusion criteria and excluded if they failed to meet any one of the inclusion criteria or met exclusion criteria (not covid-19 patients, lack of pre-post intervention data, no intervention provided to group). A synthesis without meta-analysis was conducted due to a high heterogeneity of methods in the included studies. Three outcomes were synthesised via a combination of p-values: exercise capacity, pulmonary function and HrQoL. Results: Six studies were identified as eligible for inclusion. Study design, sample size, intervention provided and outcome measures varied between studies. A very low level of evidence was observed for a positive effect of PR on exercise capacity and HrQoL, and a very low level of evidence was observed for some positive effect of PR on pulmonary function. Conclusions: The limited effect of PR on exercise capacity, pulmonary function and HrQoL observed in this systematic review is promising and an indication that PR is superior to no intervention in inducing improvements in these outcomes in COVID-19 survivors. However the limited availability of high-level clinical trials leads to an inability to reach any definitive conclusions about the effects of PR on the assessed outcomes