Objective: The objective of this systematic review was to synthesize evidence from randomized controlled trials (RCTs) regarding the efficacy of music-based interventions (MBIs) in improving anxiety and depression in older adults with dementia.

Methods: Relevant RCTs were identified through searches in electronic databases, including PubMed, Embase, EBSCOhost, Scopus, Web of Science, APA PsycINFO, and Google. The Revised Cochrane risk-of-bias tool for randomized trials (RoB 2) was used to evaluate the risk of bias in the included trials. A narrative synthesis of the included trials was conducted.

Results: Nine RCTs involving 496 patients met the inclusion criteria; five trials evaluated the efficacy of MBIs for anxiety, and six trials evaluated their efficacy for depression in older adults with dementia. Of the nine trials, two reported significant improvements in anxiety in older adults with dementia following MBIs (Cohen's d = -1.71 to -2.48), while one trial reported significant improvements in depression (Cohen's d = -0.66).

Conclusions: Only a few trials support the efficacy of MBIs in alleviating negative emotions in older adults with dementia, as evidenced by three out of the nine trials. However, due to the small sample sizes and heterogeneity in dementia types, stages, and interventions, quantitative results were not pooled, making it challenging to draw reliable conclusions. Further validation and examination of the findings presented in this study are warranted to strengthen the evidence base for integrating MBIs into dementia care and treatment protocols.