A Randomised Controlled Trial of Lung Volume Recruitment in Adults with Neuromuscular Disease.

Abstract

Clinical care guidelines advise lung volume recruitment (LVR) be performed routinely by people with neuromuscular disease (NMD), to maintain lung and chest wall flexibility and slow lung function decline. However, the evidence-base is limited and no randomised controlled trials (RCT) of regular LVR in adults have been published. To evaluate the effect of regular LVR on respiratory function and quality of life in adults with NMD. Randomised controlled trial with assessor blinding, conducted between September 2015 and May 2019. People (>14 years old) with NMD and vital capacity (VC) <80% predicted were eligible, stratified by disease sub-group (amyotrophic lateral sclerosis/motor neurone disease or Other NMDs) and randomised to three months of twice-daily LVR or breathing exercises. The primary outcome was change in maximum insufflation capacity (MIC) from baseline to 3-months, analysed using a linear mixed model approach. 76 participants (47% female, median age 57 (31-68) years, mean baseline VC 40±18% predicted) were randomised (LVR=37). 73 participants completed the study. There was a statistically significant difference in MIC between groups (linear model interaction effect p=0.002; observed mean difference = 0.19 [0.00 to 0.39] L). MIC increased by 0.13 [0.01 to 0.25] L in the LVR group, predominantly within the first month. No interaction or treatment effects were observed in secondary outcomes of lung volumes, respiratory system compliance or quality of life. No adverse events were reported. Regular LVR increased MIC in a sample of LVR-naïve participants with NMD. We found no direct evidence that regular LVR modifies respiratory mechanics or slows the rate of lung volume decline. The implications of increasing MIC are unclear, and the change in MIC may represent practice. Prospective long-term clinical cohorts with comprehensive follow-up, objective LVR usage, and clinically meaningful outcome data are needed. Australian New Zealand Clinical Trials Registry ACTRN12615000565549 (anzctr.org.au) Primary Source of Funding: National Health and Medical Research Council/Motor Neurone Disease Research Institute of Australia co-funded Postgraduate Scholarship (2014/GNT1093831); Mavis Gallienne MND Victoria grant (GIA 1703); Institute for Breathing and Sleep grants (2014, 2018); Physiotherapy Research Foundation grant (S14-013).