Date of Award
Selective Evidence-Based Medicine Review
Master of Science in Health Sciences - Physician Assistant
Physician Assistant Studies
Objective: The objective of this selective EBM review is to determine whether or not psilocybin is an effective treatment to reduce depression and anxiety in cancer patients with a diagnosis of an anxiety disorder, mood disorder, and/or stress disorder.
Study design: Systematic review of three cross-over randomized placebo-controlled trials published in peer reviewed journals between 2010-2016.
Data sources: All articles were published in English and were selected from Cochrane Collaboration and PubMed based on if they were relevant to my clinical question and included patient-oriented outcomes (POEMs).
Outcomes measured: Outcomes measured included self-reported anxiety and depression via the State-Trait Anxiety Inventory (STAI) and the Beck Depression Inventory (BDI), respectively.
Results: Grob et al. (Arch Gen Psychiatry. 2011;68(1):71-78. doi: 10.1001/archgenpsychiatry. 2010.116) found that controlled use of psilocybin when compared with placebo improved selfreported anxiety (p<0.001) and depression (p=0.05) in cancer patients. Further study by Griffiths et al. (J Psychopharmacol. 2016;30(12):1181-1197. doi: 0269881116675513) demonstrated that a therapeutic dose of psilocybin can statistically significantly reduce both cancer-related anxiety (p<0.01) and depression (p<0.05). Lastly, Ross et al. (J Psychopharmacol. 2016;30(12):1165- 1180. doi: 0269881116675512 [pii]) found that single moderate dose psilocybin in conjunction with psychotherapy produced statistically significant clinical benefits in terms of reduction of anxiety (p<0.001) and depression (p<0.01) in patients with cancer and was significantly more effective than placebo with psychotherapy.
Conclusion: All three randomized controlled trials found a statistically significant reduction in self-reported anxiety via STAI scores when patients were treated with psilocybin versus placebo. Two of the three studies reported a statistically significant decrease in self-reported depression via BDI scores, with the third reporting substantial decrease but narrowly missing statistically significance. Future studies should be done that are not cross-over design in order to improve blinding and therefore validity of the study, and with larger, more diverse patient populations to increase the generalizability of these results.
Reichenbach, Brooke, "Is Psilocybin an Effective Treatment to Reduce Depression and Anxiety in Cancer Patients with a Diagnosis of an Anxiety Disorder, Mood Disorder, And/Or Stress Disorder?" (2020). PCOM Physician Assistant Studies Student Scholarship. 531.