BMJ
Psilocybin effective for treating depression symptoms, meta-analysis finds
BMJ EXPRESSION OF CONCERN: Efficacy of psilocybin for treating symptoms of depression: systematic review and meta-analysis
This notice alerts readers to an error with this paper by Athina-Marina Metaxa and Mike Clarke (BMJ 2024;385:e078084. published 01 May 2024). The journal and the authors are investigating the problem. The study analyzed data from randomized trials of psilocybin for the treatment of depression in adults. A methodological concern has been raised about an error in the calculation of standardized mean differences. This is likely to have overestimated the benefits of psilocybin. The authors are reviewing and responding to the error and its implications for the findings and conclusions of the paper. The authors’ response will be reviewed by BMJ who will decide what further action is needed.
Researchers found that treatment effects of psilocybin were significantly larger among patients with secondary depression when self-report scales were used to measure symptoms of depression, and when participants had previously used psychedelics. Authors call for further research to determine the influence of expectancy effects, moderating factors, and treatment delivery on the efficacy of psilocybin as an antidepressant.
- This meta-analysis included 436 participants (228 female; average age 36-60 years), from seven of the nine included studies and showed a significant benefit of psilocybin (Hedges' g=1.64, 95% confidence interval (CI) 0.55 to 2.73, P<0.001) on change in depression scores compared with comparator treatment.
- Subgroup analyses and metaregressions indicated that having secondary depression (Hedges' g=3.25, 95% CI 0.97 to 5.53), being assessed with self-report depression scales such as the Beck depression inventory (3.25, 0.97 to 5.53), and older age and previous use of psychedelics (metaregression coefficient 0.16, 95% CI 0.08 to 0.24 and 4.2, 1.5 to 6.9, respectively) were correlated with greater improvements in symptoms. In addition, those with depression and a life threatening illness appeared to benefit more from treatment.
Source:
Metaxa AM, et al. (2024, May 1). BMJ. Efficacy of psilocybin for treating symptoms of depression: systematic review and meta-analysis. https://pubmed.ncbi.nlm.nih.gov/38692686/