Psilocybin-Assisted Psychotherapy in Complex Clinical Populations

Post by Flora Moujaes

What's the science?

Dubbed the ‘psychedelic renaissance’, a growing number of studies have emerged showing that psychedelic-assisted psychotherapy is beneficial for everything from treatment-resistant depression and PTSD to demoralization in terminally ill patients. Modern trials of psychedelic-assisted psychotherapy use carefully screened clinical populations, often excluding patients who have comorbid diagnoses where one or more disorders occur at the same time, or who have a history of psychosis. But what happens when psychedelic-assisted psychotherapy is utilized in more complex clinical populations? This week in EClinicalMedicine, Anderson and colleagues explored whether psilocybin-assisted psychotherapy is effective in treating distress in long-term AIDS survivors.

How did they do it?

The researchers conducted an open-label pilot study where over the course of seven weeks participants underwent three hours of individual psychotherapy, 12-15 hours of group therapy, and one eight hour individual psilocybin administration. Eighteen older long-term male AIDS survivors took part in the study and were divided into three groups of six for the group sessions. This population was selected as it is known to have a higher degree of demoralization and loss. Participants received a moderate/high dose of psilocybin: 0.3-0.36 mg/kg. The main clinical outcome measure was change in demoralization from baseline at the end of the study and three months after the study had been completed.

The patients used in this study had a much higher rate of co-occurring psychiatric disorders than has been seen to date in the modern literature on psilocybin therapy. The patients had a range of psychiatric diagnoses including clinically active Borderline Personality Disorder (BPD), General Anxiety Disorder, Major Depressive Disorder, and Panic Disorder. They had also experienced a high degree of adverse life experiences.

What did they find?

Effect on Demoralization: Researchers found that there was a significant improvement in self-reported demoralization at both the end of the study, and three months after the study had been completed. In response to the feedback from the first group of six patients who partook in the study, the amount of post-drug group therapy visits was increased from four to six, suggesting that more complex clinical populations may need more support following the psilocybin session.

Fourteen out of 18 patients experienced expected moderate-to-severe adverse reactions to psilocybin including paranoia, transient thought disorder (e.g. dissociation with repeated self-talk), anxiety, nausea, and visual and tactile hallucinations. Twelve participants experienced moderate-severe high blood pressure, which seemed to co-occur with anxiety and in most cases self-resolved when clinicians calmed patients verbally. However, one participant who met the criteria for BPD was intermittently severely hypertensive for four hours, and his paranoia precluded the clinicians from offering oral medications to help lower his blood pressure. Finally, two participants experienced unexpected reactions to psilocybin: one participant experienced a post-traumatic stress flashback related to a previous sexual assault two days after receiving psilocybin, while another reported severe anxiety 10 days after receiving psilocybin and then had a lapse in his methamphetamine use and withdrew from the study.

What's the impact?

Overall this study characterized the potential efficacy of psilocybin-assisted psychotherapy in treating distress in long-term AIDS survivors. However, given that moderate-severe side effects occurred in 14 out of 18 patients, this study highlights the importance of thorough screening, experienced clinicians, and providing ample therapeutic support after the substance session. This study also supports prior reports suggesting that patients with BPD traits may have more difficulty tolerating psilocybin. In summary, this study provides invaluable insights into the nuances of psychedelic-assisted psychotherapy in clinical populations. 

Anderson et al. Psilocybin-assisted group therapy for demoralized older long-term AIDS survivor men: An open-label safety and feasibility pilot study. EClinicalMedicine (2020). Access the original scientific publication here.