Acoustic, respiratory, cognitive and wellbeing comparisons of two groups of people with Parkinson’s disease participating in voice and choral singing group therapy (VCST) versus a music appreciation activity

Abstract

Background: Group singing as an effective non-pharmacological intervention for voice and wellbeing in people with Parkinson’s disease is attracting attention, however a review of the literature indicates only a small number of studies completed in the past decade, all with methodological differences and an absence of randomised controlled trials (RCTs). LSVT® is the current mainstream voice treatment for people with PD. It is a formalised, high effort and intensive clinic based intervention. It is considered effective, however, there are limitations; insufficient availability and prescription, high administration costs related to the intensity of required client contact time and access limitations because of physical impairments can all result in significant numbers of participants dropping out. Aim: The aim of this thesis is to evaluate how an alternative therapy, intensive choral singing, improves the phonatory and respiratory muscle control of people with PD and how the mutually supportive nature of group singing might facilitate social interaction and improve wellbeing. A preliminary study (Study 1) investigated five self-report measures of symptom severity, wellbeing and voice to determine whether they were acceptable, reliable and sensitive to the effects of PD. A two armed, parallel RCT design (Study 2) was used to compare outcomes for a Choir group who participated in singing, voice and respiration exercises and a Music group who participated in watching and discussing music videos. Both groups attended once per week sessions over nine consecutive weeks (16 hours). Findings: Internal reliability of self-report measures in Study 1 was good to excellent. Analysis showed significant intra subject reliability with no significant change over two test administrations separated by four weeks, with the exception of the ACE-lll. Analysis of variance of pre and post assessments of voice volume and quality, respiratory and glottal function and cognition and self-report measures in Study 2 showed significant within-group improvement for the Choir group, but not for the Music group, for voice volume and quality, maximum sustained phonation time and functional symptom severity. Other measures of voice volume were improved for both groups. When outcomes were compared between groups at the end of the intervention period, significant between-group differences were observed in average and maximum voice volume (MSP), voice quality (VTI and SPI) and glottal function (ARES). Choir group and Music group attendance was over 96% during the treatment period suggesting that both groups found the nature and format of the activities enjoyable and worthwhile. Conclusion: This study contributes further evidence of group singing as an effective voice intervention that has a high participation uptake and low drop out and provides further support for the use of group singing an effective alternative to LSVT®.