Although vesicular monoamine transporter type 2 (VMAT2) inhibitors may be an effective treatment for chronic tic disorders (CTD), including Tourette syndrome (TS), no meta-analysis of existing evidence from randomized controlled trials had been published (RCTs). For a study, researchers sought to assess the effectiveness, acceptability, and tolerability of VMAT2 inhibitors for CTD/TS, so they conducted a systematic review and meta-analysis. The databases PubMed, CENTRAL, and Embase were searched for double-blind RCTs comparing VMAT2 inhibitors to placebo for the treatment of CTD/TS. Close to 12 weeks, the change in tic severity evaluated by the Yale Global Tic Severity Scale (efficacy) and rates of cessation due to side effects (tolerability) or all reasons (acceptability) were extracted. The impact size indices for effectiveness and acceptability/tolerability were mean difference (MD) and odds ratio (OR), respectively. The data were pooled using random-effects meta-analysis with inverse variance weighting. Five randomized controlled trials with eight comparisons were considered. A meta-analysis revealed a nonsignificant effect on effectiveness (k=8; N=583; MD=0.71; 95% CI,1.93 to 0.50; P=0.24), with assurance that the real effect is non clinically relevant (high quality of evidence). The meta-analysis discovered decreased tolerability (k=7; N=626; OR=2.67; 95% CI, 1.21–5.92; P=0.01) and decreased acceptability (k=8; N=626; OR=1.90; 95% CI, 1.14–3.18; P=0.01), though these comparisons were limited due to the relatively small number of events across trials. Meta-analyses did not support the efficacy of VMAT2 inhibitors in the short-term treatment of tic disorders and indicated that these medicines had no clinically relevant effect on tic symptoms.
Reference:movementdisorders.onlinelibrary.wiley.com/doi/10.1002/mds.28957
