Active Music Interventions and Music Therapy in Motor Neuron Disease: A Systematic Review

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Active Music Interventions and Music Therapy in Motor Neuron Disease: A Systematic Review

In plain language

This systematic review investigates the effectiveness of music interventions and music therapy in quality of life and symptom management in individuals with motor neuron disease. Out of 183 articles initially identified, only two articles were found to fit the inclusion criteria. One study reported positive outcomes in quality of life following music therapy, while the other reported no significant change in physiological or psychological measures studied. Due to limited available evidence, the effectiveness of music interventions in patients with motor neuron disease remains unknown. Future research is needed to adequately assess the effectiveness of music therapy on physiological and psychological outcomes in motor neuron disease.


Abstract

The purpose of this systematic review was to investigate the clinical effectiveness of active music-based interventions and music therapy for physiological and psychological outcomes in patients with motor neuron disease. Four online databases were searched from inception to June 2020 in addition to a hand search. Inclusion criteria were: original article published in English available in full text; included participants with motor neuron disease; employed an active music-based intervention or music therapy (i.e. interventions that involved only passive music listening were excluded); pre- and post-intervention measures reported. Screening was completed using the online Covidence platform and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA-2009). The QualSyst critical appraisal tool and the Oxford Centre for Evidence-Based Medicine Levels of Evidence were used to assess study quality and level of evidence. Of the 183 articles initially identified, only two met inclusion criteria, both of which were conducted by an accredited music therapist. Intervention procedures and outcome measures differed between studies. One randomised controlled trial reported positive outcomes in quality of life, while the other repeated measures study reported no changes in physiological and psychological measures. Due to limited available evidence, the effectiveness of music therapy for psychosocial and physiological outcomes in patients with motor neuron disease remains unknown. Further research utilising larger sample sizes is needed to adequately assess the effectiveness of music therapy in motor neuron disease on physiological and psychological outcomes.


Citation

Flagge, A. G., Pierce, B., Garand, K. L. (Focht), & Ra, S. H. (2021). Active music interventions and music therapy in motor neuron disease: A systematic review. Australian Journal of Music Therapy, 32. Retrieved from https://www.austmta.org.au/journal/article/active-music-interventions-and-music-therapy-motor-neuron-disease-systematic-review


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Date published: April 2021

Introduction

     Motor neuron disease (MND) encompasses a group of fatal neurological disorders in which there is degeneration of motor neurons resulting in impairments of voluntary muscle activity related to breathing, limb (e.g., walking) and bulbar functioning (e.g., speaking, swallowing). Amyotrophic lateral sclerosis (ALS) is the most common form of MND and unique in its underlying pathophysiology since it results in degeneration of both upper and lower motor neurons. Irrespective of the type of MND, almost all patients will develop bulbar dysfunction resulting in speech and swallowing impairments (dysarthria and dysphagia, respectively) (Leighton et al., 1994; Onesti et al., 2017). Bulbar dysfunction contributes to poorer outcomes, including shortened life expectancy (Chio et al., 2009). Additionally, research in MND suggests that poor psychological status is associated with faster disease progression and shorter survival (Johnston et al., 1999; McDonald et al., 1994). Since there is no cure for MND, current treatment focuses on managing physiological symptoms and promoting quality of life, including psychological counseling, respiratory therapy, and nutritional management (Andersen et al., 2012; Epps et al., 2020; Plowman et al., 2017; Raglio et al., 2016; Tiryaki & Horak, 2014).

     Interventions employing the use of music have shown promise as an effective intervention for treating symptoms resulting from various neurological disorders, including degenerative types (Devlin et al., 2019). Music interventions may be implemented by any healthcare provider, such as a nurse, speech-language pathologist, or recreational therapist. In contrast, music therapy (MT) must be implemented by an accredited music therapist who has earned at least a bachelor's degree with a requirement of a six-month internship pre-graduation (Devlin et al., 2019). MT can include both passive (e.g. listening to music) and active (e.g. singing, playing an instrument) participation, and both types of interventions have been shown to improve both psychological and/or physiological symptoms in different clinical populations (see Raglio et al. (2015) for a review of the use of passive and active techniques in various neurological populations). Passive music listening has been found to improve mood in patients with dementia (Guetin et al, 2009) and post-stroke (Sarkamo et al., 2008). Active MT has been found to improve quality of life (QoL) in individuals with stroke, dementia, and Parkinson’s disease (Cho, 2018; Raglio, 2015; Spina et al., 2016). Additionally, MT applied in Parkinson’s disease has been effective in the areas of cognitive functioning (attention, memory, executive function) and language abilities (Raglio, 2015).

     Active MT has also been demonstrated as beneficial for motor symptoms (e.g. gait) in both neurological and non-neurological disorders (Devlin et al., 2019). Improvements in bulbar function, specifically swallowing function, were observed following MT interventions in patients post-stroke (Kim, 2010), dementia (Jomori & Hoshiyama, 2010), brain injury (Jomori & Hoshiyama, 2010), and Parkinson’s disease (Stegmoller et al., 2017). For example, Jomori and Hoyshiyama (2010) observed an increase in involuntary swallowing (swallows not related to oral ingestion of liquid/food) frequency during MT (singing and rhythm activities) compared to resting state in a heterogeneous cohort of older patients with various neurologic conditions, such as dementia and brain injury.  Involuntary swallows support saliva management and oral health in neurological populations, which can reduce the risk of potentially life-threatening pulmonary complications resulting from aspiration (ingested material entering the airway). 

     Despite inherent pathophysiological differences amongst neurodegenerative diseases, patients with MND exhibit motor impairments similar to those seen in patients with dementia and Parkinson’s disease, including bulbar dysfunction, and also exhibit similar impairments in psychosocial and cognitive functioning. Therefore, because of the previously reported positive effects of active music interventions, especially MT, in acute neurological and other neurodegenerative populations, the purpose of this systematic review was to specifically examine the effectiveness of music intervention and MT on both physiological and psychological outcomes in patients with MND.

Methods

Protocol

     Reporting was performed following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) (Moher et al., 2009).

Search Strategy

     Search and screening protocols were conducted in accordance with PRISMA guidelines (Moher et al., 2009). A search strategy was developed and implemented in four electronic bibliographic databases: PubMed, Scopus, CINAHL, and Cochrane library. A hand search was also completed to check for any additional sources of data by reviewing reference lists from articles identified in the search process.

     Each database was searched using the following key terms: “music therapy” OR “music intervention” OR “neurologic music therapy” AND “motor neuron disease” OR “amyotrophic lateral sclerosis” OR “ALS.” All database search results were imported into the online platform Covidence (2019) for further review. All studies published from database inception to 9 June, 2020 were collected for further determination of eligibility by one author.

Eligibility Criteria

     Covidence (2019) software automatically removed duplicate articles found in the database searches. The remaining articles were independently screened by one author for relevance according to their titles and abstracts. Full text of the relevant titles were uploaded to Covidence (2019), and those deemed ineligible according to established criteria were excluded from further analysis. If eligibility was considered questionable, inclusion was discussed with a second author and a consensus regarding eligibility was reached.

     To be considered eligible for inclusion, the following criteria were utilised: original research article which employed a music-based or music therapy intervention; repeated measures pre and post intervention reported; published in the English language; and, available in full text. Studies were excluded if they did not involve participants with a diagnosis of MND as the population of interest. Further, because the primary interest in this study was to examine the impact of active participation in music intervention, eligible studies were required to involve an active music intervention or MT in some form; therefore, studies which involved only passive music exposure (e.g. listening to music) were excluded. Active MT referred to participants actively involved in the therapy session, such as making music, participating in music-assisted relaxation, writing/ substituting lyrics, and/or otherwise engaging with the therapist/interventionist (see Table 1 for further description of activities). Because ALS is a rare disease with no standard treatment, interventions involving any type of active music interaction were included in the initial search.

Table 1.
Characteristics of Eligible Studies Included in Systematic Review

 

Horne-Thompson & Bolger (2010)

Raglio (2015)

Study Participants

N=21(mean age: 61.7 years)

N = 30

Experimental group: n=15 (mean age: 62.9 years)

Control group: n=15 (mean age: 65.1 years)

Description of Music Intervention

Three sessions (30 mins each) completed within a one-week period:

  • One live session

  • One recorded session

  • One control session

Live sessions included:

  • Music relaxation

  • Playing/singing familiar songs

  • Music assisted counseling

  • Music and imagery

  • Songwriting/lyric substitution

  • Instrument playing

  • Recorded song selection

Twelve sessions (30 mins each) completed within a one-month period

Experimental group received active music training, which included: use of melodic and rhythmic instruments by therapist and participant to produce improvised music

Control group received only standard of care intervention

Outcome Measures

HADS

ESAS

Pulse oximetry

HADS

MQoL

ALSFRS-R

Results

No significant changes observed in any measure following music therapy

HADS: significant improvement for both experimental and control groups following intervention

MQoL: both groups showed improvement over treatment course, with only experimental group maintaining improvement two months post-treatment

ALSFRS-R: both groups exhibited clinically non-significant decrease in function (more pronounced in control group)

Note: HADS: Hospital Anxiety and Depression Scale; ESAS: Edmonton Symptom Assessment System; MQoL: McGill Quality of Life Assessment; ALSFRS-R: Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised

Quality Assessment

     Two authors independently judged each of the eligible articles for level of evidence using the Oxford Centre for Evidence-based Medicine Levels of Evidence (Howick et al., 2009) and for strength (quality) of evidence using the QualSyst critical appraisal tool (Kmet et al., 2004). The QualSyst is a 14-item assessment measure that examines study design, risk of bias, participant selection and description, and intervention and analysis methods and reporting (Kmet et al., 2004). For each item, a score of 2 was awarded if criteria were completely met, 1 was awarded for partial satisfaction of criteria, and 0 was awarded if criteria were not met. Questions that did not qualify for judgment were denoted in the ‘not applicable’ (N/A) column. Scores were calculated for each study by totaling the number of points assigned and dividing by the total points possible (minus the number of N/A scores). Each study was subsequently judged based on quality: a score > 80% was considered strong quality; a score between 60-79% was considered good quality; a score between 50-59% was considered average quality; and a score < 50% was considered poor quality. Consensus was used when disagreements occurred between the two raters.

Results

     The initial search yielded 183 articles, of which only two met the eligibility criteria as depicted in Figure 1. It should be noted that although the inclusion criteria for what was considered a ‘music intervention’ was quite broad, both eligible studies were conducted by music therapists that were certified and accredited in their respective countries.

Figure 1. Adapted PRISMA Flowchart Showing Process of Study Selection

Study Design and Methodological Quality

     Table 2 provides the level of evidence of methodological quality of the studies included. Horne-Thompson & Bolger (2010) utilised a repeated measures methodology in which the individuals served as their own controls (Level 4). A ‘good’ quality rating was awarded to this study due to its description of patient characteristics, small sample size, and estimation of variance. Raglio and colleagues (2016) conducted a ‘strong’ quality randomised control trial (RCT) with blinding (Level 1b).

Table 2.
Levels of Evidence and Quality of Included Studies

Study

Level of evidence

QualSyst score

Quality

Horne-Thompson & Bolger

4 (case series)

77%

Good

Raglio et al.[4]

1b (randomised controlled trial)

81%

Strong

 

 

 

 

Participant Characteristics

     The study conducted by Horne-Thompson and Bolger (2010) included 21 participants diagnosed with motor neuron disease residing in an inpatient hospice neurological ward, although five participants died or withdrew before the study was complete. The mean age of the participants was 61.7 years. The majority of participants were male (71%), which is comparable to the reported male/female incidence in prior studies (Horne-Thompson & Bolger, 2010, Kmet et al., 2004).

     The RCT conducted by Raglio and colleagues (2016) included an experimental (n=15; 7 males) and a control (n=15; 6 males) group of hospitalised patients. All participants were diagnosed with ALS or primary lateral sclerosis. The mean age of participants in the experimental and control groups were 62.9 and 65.1 years, respectively.

Type of Music Therapy and Effectiveness of Treatment

     Horne-Thompson and Bolger (2010) employed three music therapy sessions, each representing a different treatment condition in order to assess the effectiveness of three different types of music therapy. Each session was completed on a different day and lasted 30 minutes. All three sessions (representing different MT conditions) were completed within a one-week period for each participant. In this Australian-based study, one session was live music therapy administered by a Registered Music Therapist (RMT) selecting one or more music-related activities based on the participant’s needs. Techniques used in the live session included one or more of the following: music relaxation, playing/singing familiar songs, music assisted counseling, music and imagery, songwriting/lyric substitution, instrument playing, and recorded song selection and discussion. The second condition was a recorded music session, in which the participant selected a disc to listen to. The final treatment condition was a control session which involved the participant performing a non-music related task, during which the therapist was present. The order of these three sessions was randomly assigned for each participant.

     Horne-Thompson & Bolger (2010) used two patient-reported outcome measures (PROMs), the Hospital Anxiety and Depression Scale (HADS) and the Edmonton Symptom Assessment System (ESAS) to assess mood and symptom severity, respectively. Each of these measures was given before and after each MT session. Pulse oximetry was used to record heart rate and oxygen saturation levels, and was taken by staff not directly involved in the study both before and after each MT session. This study yielded no significant change in PROMs or pulse oximetry measures for any of the three MT intervention conditions.

     The study by Raglio et al. (2016) was an Italian-based RCT conducted over approximately one month, which included 12 sessions that were video recorded. Each session was 30 minutes long and occurred three times a week. The control group received the ‘standard of care (SC)’ treatment each session. The SC consisted of physical, speech, and occupational therapy as well as psychological counselling. The experimental group received active music therapy (AMT) in addition to the SC. During AMT, a trained music therapist used a musical modality (melodic and rhythmic instruments) to engage the participant with the goal of communication or interaction. The basis of this approach is “free sonorous-music improvisation” where the participant and therapist collaborate to produce music (Raglio et al., 2016).

     Raglio et al. (2016) also investigated changes in PROMs, including the HADS and the Italian version of McGill Quality of Life Questionnaire (MQoL). Further, the ALS Functional Rating Scale-Revised (ALSFRS-R) was also utilised, which evaluates function across bulbar, respiratory, and limb systems. Data was collected across three time periods: baseline (T0), end of treatment (T1), and two months post-treatment (T2). At baseline, there was little presence of anxiety or depression in either the experimental or control group prior to intervention. Scores for the HADS demonstrated significant improvement for both groups following intervention (global p-value = 0.026); however, the low anxiety levels at baseline made interpretation of clinical significance difficult. ALSFRS-R scores showed a non-significant decrease (indicating reduced function) in the AMT group, and a significant decrease in the SC group. Additionally, while both the SC and AMT groups showed improved quality of life (QoL) over the time course of treatment, the AMT group was able to maintain this improvement two months post-treatment, while the SC group did not, leading to a significant difference in global QoL measures between groups.

Discussion

     This systematic review elucidates the lack of evidence related to the utility of music intervention in patients with MND as minimal studies exist to appropriately evaluate its effectiveness. The use of live and recorded music therapy in Horne-Thompson & Bolger’s (2010) study yielded no significant improvement in symptoms of anxiety or depression (as measured by the HADS), or significant improvement in symptoms (as measured by the ESAS) for participants with MND. It is likely that the small sample size and lack of reported anxiety at baseline contributed to the lack of significant results. As reported by investigators, attrition was also an issue in this study, as five of the 21 patients enrolled in the study either died or withdrew before completion.

     While results from Raglio and colleagues (2016) did show statistically significant improvement from baseline to post-intervention for anxiety and depression (HADS), this study did not find any significant differences between the experimental and control groups, potentially due to low reported scores at baseline for both groups, indicating minimal to no anxiety or depression prior to intervention. However, participants in this study who were treated with AMT maintained improved scores on the HADS from T1 to T2, and also maintained a significantly higher overall quality of life (MQoL), compared to a control group receiving only standard of care. This suggests that AMT, which engages the subjects in therapy, shows potential long-lasting benefit for patients with MND.

     As stated by the authors of both studies, the lack of post-intervention improvement seen in measures of anxiety and depression in these two studies was likely the result of a floor effect at baseline, suggesting low levels of both anxiety and depression prior to intervention. This is in line with several other studies conducted in the MND population, suggesting overall low levels of anxiety (Bungener, 2006; Bungener et al., 2005; Clarke et al., 2001; Goldstein et al., 2006; Kurt et al., 2007; Moore et al., 1998; Rabkin et al., 2000), possibly as a result of patient adjustment or acceptance of the condition, even despite more severe symptoms (Cui et al., 2015).

     The statistically significant difference found between groups in quality of life measures by Raglio and colleagues (2016) was seen because quality of life (MQoL) was maintained from immediately post-intervention (T1) to two months post-intervention (T2). AMT was found to also reduce physical symptom perception, although not significantly. Authors suggested that the study showed beneficial effects of AMT intervention on quality of life. However, it should be noted that the study did not report effect sizes or discuss the clinical significance of these changes over time, and therefore, it is difficult to make generalisations to clinical application of AMT. Based on these two studies alone, it is difficult to determine the effectiveness of MT in this population. The lack of evidence and available literature in this area highlights the need for future research.

     While these two studies provide a window of insight into the use of music therapy in the MND population, there are several important limitations that should be discussed. First, both studies examined the use of MT for individuals in an in-patient hospital setting, which, in addition to the small sample sizes for both studies, makes generalisation difficult. Additionally, both studies focused largely on quality of life measures, with very little attention given to the impact on physiological functions, such as those related to swallowing that have been previously investigated in the literature in other neurological populations. While Horne-Thompson & Bolger (2010) did address heart rate and oxygen saturation level as a measure of anxiety (with non-significant findings post-intervention), there were no additional assessments of physiological change evaluated in either study. Given prior research in other clinical populations showing improvements in bulbar function following music therapy (Onesti et al., 2017; Stegmoller et al., 2017), and given the high prevalence of bulbar dysfunction in patients with MND (Muscaritoli et al., 2012), there is a significant need for future research to focus on the impact of music therapy on physiological symptoms of MND, specifically those related to bulbar function. High quality studies examining the effectiveness of music therapy on respiratory and phonatory function, as well as the impact of music therapy on swallowing could hold important implications for the use of music therapy in the MND populations. In conclusion, future research examining the effectiveness of MT on the physiological symptoms of MND is needed to determine if a standard treatment protocol can be developed.

Limitations

     This review has limitations that should be considered. First, only full-text articles published in the English language were considered for review. Also, only two articles satisfied the inclusion criteria, which significantly limits the generalisability of determining the effectiveness of music interventions in patients with MND.

Conclusion

     This systematic review explores potential benefits of music therapy in the MND population. Unfortunately, only two studies were included in the final review. Considering the rarity of MND in the general population, these findings were not surprising. However, it does bring to light the need for further research on the effectiveness of music therapy in both psychological and physiological aspects of the disease. Although there is emerging support for music therapy’s effectiveness in improving QoL in MND, these results speak to the need for further research. Further exploration is needed to address the full impact of music therapy on quality of life, as well as to as examine the effectiveness of music therapy on physiological measures, particularly related to bulbar-related functions, as most patients will have bulbar dysfunction during the disease course.

Funding

     Support for this project was provided, in part, by funding from the University of South Alabama Summer Undergraduate Research Fellowship (SURF), which was used to pay an undergraduate research assistant.

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