What is the issue?
Lung transplant is often the final treatment option in people with chronic lung disease. It is suggested that patients who have had a lung transplant undertake exercise training in order to speed up their recovery. This should help with their return to usual activities and improve their quality of life. However, the exact benefits of exercise training on this patients are not clear and currently there are no clear guidelines to recommend how the exercise training should be undertaken.
What did we do?
We searched electronic databases and records of clinical studies and reviewed the references of research-related to this topic. We aimed to identify studies that would help us understand the effects of exercise training in adult lung transplant recipients. We also evaluated the quality of the studies included in this review.
What did we find?
We found eight studies that met the requirements to be included in this review. Two studies compared resistance exercise training with usual care or no exercise training, three studies compared resistance exercise training with another type of resistance exercise training, two studies compared a multimodal exercise training (several different exercises) with usual care or no exercise training, and one study compared the same multimodal exercise training program undertaken for 7 and 14 weeks.
We are very uncertain about the effects of exercise training for any of our outcomes. While some studies reported improvement in the distance walked over 6 minutes (exercise versus no exercise, different exercise programs) muscle strength (exercise or multimodal exercise versus no exercise) and bone mineral density (exercise versus no exercise), most reported no differences in adverse events, quality of life, pulmonary function, or the risk of death.
The quality of evidence of the included studies was very low. Participants and study personnel were not blinded to the treatment they received due to the nature of the physical interventions and there was a frequent reporting bias. Besides, all estimates of results were imprecise mainly due to the small number of participants.
Conclusions
In adults undergoing lung transplantation the evidence about the effects of exercise training is very uncertain in terms of maximal and functional exercise capacity, HRQoL and safety, due to very imprecise estimates of effects and high risk of bias.
In adults undergoing lung transplantation the evidence about the effects of exercise training is very uncertain in terms of maximal and functional exercise capacity, HRQoL and safety, due to very imprecise estimates of effects and high risk of bias.
Pulmonary transplantation is the final treatment option for people with end-stage respiratory diseases. Evidence suggests that exercise training may contribute to speeding up physical recovery in adults undergoing lung transplantation, helping to minimize or resolve impairments due to physical inactivity in both the pre- and post-transplant stages. However, there is a lack of detailed guidelines on how exercise training should be carried out in this specific sub-population.
To determine the benefits and safety of exercise training in adult patients who have undergone lung transplantation, measuring the maximal and functional exercise capacity; health-related quality of life; adverse events; patient readmission; pulmonary function; muscular strength; pathological bone fractures; return to normal activities and death.
We searched the Cochrane Kidney and Transplant Specialised Register up to 6 October 2020 using relevant search terms for this review. Studies in the CKTR are identified through CENTRAL, MEDLINE, and EMBASE searches, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov.
Randomised controlled trials (RCTs) were included comparing exercise training with usual care or no exercise training, or with another exercise training program in terms of dosage, modality, program length, or use of supporting exercise devices. The study population comprised of participants older than 18 years who underwent lung transplantation independent of their underlying respiratory pathology.
Two authors independently reviewed all records identified by the search strategy and selected studies that met the eligibility criteria for inclusion in this review. In the first instance, the disagreements were resolved by consensus, and if this was not possible the decision was taken by a third reviewer. The same reviewers independently extracted outcome data from included studies and assessed risk of bias. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.
Eight RCTs (438 participants) were included in this review. The median sample size was 60 participants with a range from 16 to 83 participants. The mean age of participants was 54.9 years and 51.9% of the participants were male. The median duration of the exercise training programs for the groups undergoing the intervention was 13 weeks, and the median duration of training in the active control groups was four weeks. Overall the risk of bias was considered to be high, mainly due to the inability to blind the study participants and the selective reporting of the results.
Due to small number of studies included in this review, and the heterogeneity of the intervention and outcomes, we did not obtain a summary estimate of the results.
Two studies comparing resistance exercise training with no exercise reported increases in muscle strength and bone mineral density (surrogate outcomes for pathological bone fractures) with exercise training (P > 0.05), but no differences in adverse events. Exercise capacity, health-related quality of life (HRQoL), pulmonary function, and death (any cause) were not reported.
Three studies compared two different resistant training programs. Two studies comparing squats using a vibration platform (WBVT) compared to squats on the floor reported an improvement in 6-minute walk test (6MWT) (28.4 metres, 95% CI 3 to 53.7; P = 0.029; and 28.3 metres, 95% CI 10.0 to 46.6; P < 0.05) with the WBVT. Supervised upper limb exercise (SULP) program improved 6MWT at 6 months compared to no supervised upper limb exercise (NULP) (SULP group: 561.2 ± 83.6 metres; NULP group: 503.5 ± 115.2 metres; P = 0.01). There were no differences in HRQoL, adverse events, muscular strength, or death (any cause). Pulmonary function and pathological bone fractures were not reported.
Two studies comparing multimodal exercise training with no exercise reported improvement in 6MWT at 3 months (P = 0.008) and at 12-months post-transplant (P = 0.002) and muscular strength (quadriceps force (P = 0.001); maximum leg press (P = 0.047)) with multimodal exercise, but no improvement in HRQoL, adverse events, pulmonary function, pathological bone fractures (lumbar T-score), or death (any cause).
One study comparing the same multimodal exercise programs given over 7 and 14 weeks reported no differences in 6MWT, HRQoL, adverse events, pulmonary function, muscle strength, or death (any cause). Pathological bone fractures were not reported.
According to GRADE criteria, we rated the certainty of the evidence as very low, mainly due to the high risk of bias and serious imprecision.