Is inspiratory muscle training (IMT) an acceptable treatment option for people with chronic obstructive pulmonary disease (COPD) who have declined pulmonary rehabilitation (PR) and can IMT enhance PR uptake? A single-group prepost feasibility study in a home-based setting

Abstract

ObjectivesThis feasibility study aimed to assess the acceptability of inspiratory muscle training (IMT) in people with chronic obstructive pulmonary disease (COPD) who declined pulmonary rehabilitation (PR) as a potential treatment option or precursor to PR. Objectives were to assess attitudes to IMT, PR and alternatives to PR; factors influencing adherence with IMT and acceptability of outcome measures, research tools and study protocol.DesignA pragmatic, mixed methods, prepost feasibility study was conducted. Recruitment took place over a 4-month period. Participants were followed up for a period of 6 months.SettingsIMT sessions and assessments were conducted in the domiciliary setting.ParticipantsInclusion criteria: people over the age of 35, stable COPD, Medical Research Council Dyspnoea scale of 3 or above, declined PR. Exclusion criteria: history of spontaneous pneumothorax, incomplete recovery from a traumatic pneumothorax, asthma, known recently perforated eardrum, unstable angina, ventricular dysrhythmias, cerebrovascular event or myocardial infarction within the last 2 months. Participants were selected from a purposive sample. Of the 22 potential participants screened, 11 were recruited and interviewed. Ten participants commenced IMT. Seven participants completed the follow-up assessment.InterventionEight weeks of IMT twice a day, 5 days a week with visits once weekly by a physiotherapist. Unsupervised IMT twice a day three times a week until follow-up at 6 months.OutcomesAcceptability of IMT and the study process was explored via semi-structured interviews. Adherence with IMT was assessed by the Powerbreathe K3 device and participant diaries. Uptake of PR was identified.ResultsIMT was found to be acceptable. Adherence was explored. Four people went on to participate in PR.ConclusionsFeasibility was established. A randomised controlled trial is warranted to establish efficacy and cost-effectiveness of IMT in those who decline PR and IMT as an intervention to promote uptake of PR.Trial registration numberNCT01956565; Post-results.

Translational Potential of High-Resistance Inspiratory Muscle Strength Training

“…Internal data storage allows for objective recording of intervention adherence and progression ( e.g. , changes in training load or achieved inspiratory volumes during training sessions) (95,96). Although these recordings overcome certain research limitations associated with self-reported information, objective documentation of training data does not help with IMST translation and implementation per se .…”

“…Importantly, small feasibility trials for home-based, moderate-resistance IMST were performed in clinical populations (96,98), and provided initial insight on the ability of individuals to perform an IMST intervention without researcher oversight. In one study, adults with stable COPD performed 8 wk of moderate-resistance IMST (60% PI MAX , 30 breaths twice per day, 5 d·wk −1 ), with one session supervised in person.…”

“…In one study, adults with stable COPD performed 8 wk of moderate-resistance IMST (60% PI MAX , 30 breaths twice per day, 5 d·wk −1 ), with one session supervised in person. After this 8-wk run in period, participants continued training completely unsupervised, 3 d·wk −1 , for an additional 18 wk (96). Seven of the 10 subjects enrolled completed the entire intervention.…”

“…IMST was found to be acceptable, with most participants expressing confidence in their skill and ability to use the IMST device and perform the intervention. Additionally, adherence during the unsupervised sessions was high (91% of prescribed training sessions completed), but ranged from 22% to 162% (96), indicating low use by certain participants but a desire to perform more than the prescribed number of training sessions by other participants. This suggests home-based IMST is feasible in this population and warrants a larger trial.…”

“…In studies reporting adherence to home-based IMST interventions, participants in the experimental (IMST) groups completed 76% to 91% of assigned training sessions (90,92,94,96,97). Notably, the populations enrolled in these studies included healthy older adults, adults with stable COPD, patients with heart failure, and stroke survivors.…”