Psilocybin and anxiety, quality of life and functioning in 15 veterans with hard-to-treat depression

The question

Beyond depression, does a single dose of psilocybin given with psychological support change anxiety, quality of life, day-to-day functioning and post-traumatic stress symptoms in veterans whose depression has not responded to standard treatments?

What they did

Fifteen veterans with treatment-resistant depression received one 25-mg dose of psilocybin alongside psychological support, in an open-label trial (everyone knew what they were getting). The main assessment point was three weeks after dosing, with follow-up continuing to 12 months; ten people completed the long-term follow-up. Researchers tracked anxiety (GAD-7), quality of life (Q-LES-Q-SF), functional impairment (WSAS) and PTSD symptoms (PCL-5), plus questionnaires about the acute drug experience.

What they found

At Week 3, anxiety scores fell 59% from baseline, quality-of-life scores rose 24%, and functional impairment scores fell 46%. Anxiety improvements were sustained through 12 months; quality-of-life gains were statistically significant through Week 12; functioning improvements lasted through Month 6 before fading. However, once the researchers accounted for the concurrent improvement in depression, these effects were no longer statistically significant. PTSD symptom scores were lower at all timepoints in unadjusted analyses, and measures of the acute psychedelic experience (mystical, challenging or emotional-breakthrough ratings) did not correlate with treatment response.

The fine print

Only 15 people took part and just ten reached the final follow-up, so the numbers are small and the estimates imprecise. There was no placebo or control group and no blinding, so expectation and natural recovery cannot be ruled out. These were exploratory secondary outcomes, and the improvements largely tracked with depression improvement rather than standing on their own. This summary is based on the published abstract only.

What it means

In this small uncontrolled trial, veterans reported less anxiety, better quality of life and better functioning after psilocybin with psychological support, but these gains appeared to move together with their depression improving rather than being separate effects.

Evidence grade: Very low. A very small open-label trial with no placebo group or blinding, reporting exploratory secondary outcomes in 15 people.

This summary is based on the study’s published abstract.