Jenny T van der Steen, Hanneke JA Smaling, Johannes C van der Wouden, Manon S Bruinsma, Rob JPM Scholten, Annemiek C Vink

Dementia is a clinical syndrome with a number of different causes which is characterised by deterioration in cognitive, behavioural, social and emotional functions. Pharmacological interventions are available but have limited effect to treat many of the syndrome's features. Less research has been directed towards non-pharmacological treatments. In this review, we examined the evidence for effects of music-based interventions. To assess the effects of music-based therapeutic interventions for people with dementia on emotional well-being including quality of life, mood disturbance or negative affect, behavioural problems, social behaviour and cognition at the end of therapy and four or more weeks after the end of treatment. We searched ALOIS, the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group (CDCIG) on 19 June 2017 using the terms: music therapy, music, singing, sing, auditory stimulation. Additional searches were carried out on 19 June 2017 in the major healthcare databases MEDLINE, Embase, PsycINFO, CINAHL and LILACS; and in trial registers and grey literature sources. We included randomised controlled trials of music-based therapeutic interventions (at least five sessions) for people with dementia that measured any of our outcomes of interest. Control groups either received usual care or other activities with or without music. Two review authors worked independently to screen the retrieved studies against the inclusion criteria and then to extract data and assess methodological quality of the included studies. If necessary, we contacted trial authors to ask for additional data, including relevant subscales, or for other missing information. We pooled data using random-effects models. We included 22 studies with 1097 randomised participants. Twenty-one studies with 890 participants contributed data to meta-analyses. Participants in the studies had dementia of varying degrees of severity, and all were resident in institutions. Seven studies delivered an individual music intervention; the other studies delivered the intervention to groups of participants. Most interventions involved both active and receptive musical elements. The methodological quality of the studies varied. All were at high risk of performance bias and some were at high risk of detection or other bias.At the end of treatment, we found low-quality evidence that the interventions may improve emotional well-being and quality of life (standardised mean difference (SMD) 0.32, 95% confidence interval (CI) 0.02 to 0.62; 9 studies, 348 participants) and reduce anxiety (SMD -0.43, 95% CI -0.72 to -0.14; 13 studies, 478 participants). We found low-quality evidence that music-based therapeutic interventions may have little or no effect on cognition (SMD 0.15, 95% CI -0.06 to 0.36; 7 studies, 350 participants). There was moderate-quality evidence that the interventions reduce depressive symptoms (SMD -0.27, 95% CI -0.45 to -0.09; 11 studies, 503 participants) and overall behaviour problems (SMD -0.23, 95% CI -0.46 to -0.01; 10 studies, 442 participants), but do not decrease agitation or aggression (SMD -0.07, 95% CI -0.24 to 0.10; 14 studies, 626 participants). The quality of the evidence on social behaviour was very low, so effects were very uncertain.The evidence for long-term outcomes measured four or more weeks after the end of treatment was of very low quality for anxiety and social behaviour, and for the other outcomes, it was of low quality for little or no effect (with small SMDs, between 0.03 and 0.34). Providing people with dementia who are in institutional care with at least five sessions of a music-based therapeutic intervention probably reduces depressive symptoms and improves overall behavioural problems at the end of treatment. It may also improve emotional well-being and quality of life and reduce anxiety, but may have little or no effect on agitation or aggression or on cognition. We are uncertain about effects on social behaviour and about long-term effects. Future studies should examine the duration of effects in relation to the overall duration of treatment and the number of sessions.