OBJECTIVES: To undertake a systematic review and meta-analysis to examine the evidence base for the effects of β-hydroxy-β-methylbutyrate (HMB) supplementation in patients with sarcopenia.
DESIGN: Systematic review and meta-analysis.
METHODS: The literature was searched via the PubMed, MEDLINE, Web of Science, EMBASE, CINAHL, Scopus, WANFANG, CNKI and VIP databases, through 23rd February 2024. The inclusion criteria were: randomized controlled trials (RCTs); patients diagnosed with sarcopenia defined according to well-accepted clinical consensus; HMB as an intervention; outcomes on muscle mass and/or muscle strength and/or physical performance. Data extraction was completed by independent pairs of reviewers. Meta-analyses of continuous outcomes were performed on the extracted data. Standard mean difference (SMD) with 95 % confidence intervals (CIs) between treatment and control group were used to express intervention effect estimates of HMB for each study. Risk of bias was assessed according to Version 2 of the Cochrane tool for assessing risk of bias in randomized trials (ROB 2).
RESULTS: Of 196 records retrieved and screened, five RCTs met the eligibility criteria for qualitative and quantitative analysis, yielding 154, 359 and 359 participants for muscle mass, muscle strength, and physical performance, respectively. For the overall risk of bias, no studies were graded as "high risk of bias", one (20.0 %) as "some concerns", and four (80.0 %) as "low risk of bias" according to the ROB 2. The overall meta-analysis revealed a beneficial effect on muscle mass and strength, as demonstrated by a higher skeletal muscle mass index (SMD = 0.32; 95 % CI: [0.00,0.64]; Z value =1.98; P = 0.048), along with an elevated handgrip strength (SMD = 0.65; 95 % CI: [0.05, 1.25]; Z value = 2.12; P = 0.034) in the HMB intervention groups compared with the control groups. However, there was no evidence of a benefit on physical performance, assessed by gait speed (SMD = 0.19; 95 % CI: [-0.14, 0.53]; Z value = 1.14; P = 0.255).
CONCLUSION: Overall, although limited and requiring interpretation with utmost caution, current evidence indicates that HMB supplementation is beneficial for improving muscle mass and strength, but there is no evidence of a benefit on physical performance in patients with sarcopenia. In future, more well-designed HMB intervention trials should be conducted that include populations diagnosed with sarcopenia according to well-accepted clinical consensus.
