Efficacy and dropout rates of antipsychotic medications for methamphetamine psychosis: A systematic review and network meta-analysis

Abstract

BackgroundThis study aimed to compare the treatment effects of different antipsychotics for methamphetamine psychosis (MAP). MethodsClinical Trials, Cochrane Library, Pubmed, Scopus, and Web of Science were searched for short-term, randomized controlled trials (RCTs) from the inception to June 15, 2020. Standardized mean differences (SMDs) and odds ratios (ORs) were aggregated using random-effects pairwise comparisons and frequentist network meta-analyses (NMAs). Primary outcomes of interest were the main psychotic symptoms and dropout rates. We also rated the quality of NMA estimates. ResultsThis NMA included six RCTs of 395 patients with MAP. Six studied antipsychotics were aripiprazole, haloperidol, olanzapine, paliperidone extended-release, quetiapine, and risperidone. Risperidone is the most frequently studied antipsychotic, being investigated in four trials. Low quality of evidence was available to determine the efficacy of those antipsychotics for main psychotic symptoms. Aripiprazole was significantly inferior to olanzapine (SMD = 1.36, 95 % CI = 0.46–2.26), quetiapine (SMD = 1.13, 95 % CI = 0.28–1.98), haloperidol (SMD = 0.87, 95 % CI = 0.14–1.60), and paliperidone extended-release (SMD = 0.60, 95 % CI = 0.06–1.14). Olanzapine and quetiapine were superior to risperidone (SMD = -1.09, 95 % CI = -1.89 to -0.28 and SMD = -0.86, 95 % CI = -1.61 to -0.11, respectively). The dropout rates were not significantly different among the studied antipsychotics. ConclusionsThis analysis suggests that olanzapine or quetiapine may be a preferred antipsychotic for MAP, although the evidence for this was rated low-quality due to the high risk of bias or indirectness/intransitivity.