VR may hold promise for treatment of persistent persecutory delusions

Virtual reality (VR) cognitive therapy and VR mental relaxation therapy provide comparable improvements in persistent persecutory delusion with high uptake rates, the THRIVE trial has shown.

“Persecutory delusions are a major psychiatric problem that often does not respond sufficiently to standard pharmacological or psychological treatments,” wrote the researchers. “We [therefore] developed a new brief automated VR cognitive treatment that has the potential to be used easily in clinical services.”

In a parallel-group, single-blind, randomized controlled trial, 80 patients with persistent (≥3 months) persecutory delusions (mean age, 40 years; male, 61 percent; schizophrenia, 45.0 percent; psychosis, 31.3 percent) were recruited from 21 September 2018 to 13 May 2021 (with a pause due to COVID-19 pandemic in March 2020─September 2020) and randomized 1:1 to receive either THRIVE VR cognitive therapy plus usual care or VR mental relaxation plus usual care. “Each VR therapy was provided in four sessions over approximately 4 weeks, supported by an assistant psychologist or clinical psychologist,” added the researchers. The primary outcome was persecutory delusion conviction, assessed by the Psychotic Symptoms Rating Scale (PSYRATS) in the intention-to-treat population. [Lancet Psychiatry 2023;doi:10.1016/S2215-0366(23)00257-2]

Compared with VR mental relaxation,  THRIVE VR cognitive therapy did not lead to greater improvement in the primary outcome of persecutory delusion conviction at week 4 (adjusted mean difference, 2.16; 95 percent confidence interval [CI], -12.77 to 8.44; p=0.69) or secondary outcomes of defensive behaviour use (adjusted mean difference, -0.71; 95 percent CI, -4.21 to 2.79; p=0.69) and belief in safety (adjusted mean difference, -5.89; 95 percent CI, -16.83 to 5.05; p=0.29).

Uptake rates of the two VR therapies were high, with the participants having attended a mean number of 3.7 sessions of VR cognitive therapy and 3.6 sessions of VR mental relaxation. Seventeen serious adverse effects (SAEs) occurred during the trial, including four psychiatric hospital admissions, 12 acute hospital admissions, and one death due to long-standing physical health conditions. Notably, none of the SAEs were judged to be related to the VR therapies or trial procedures.

“To our knowledge, [THRIVE was] the first clinical trial using VR to treat persistent persecutory delusions,” shared the researchers. Both VR groups showed large improvements over time, including reductions in the use of defensive behaviours and increases in safety belief. Contrary to expectation, there were no significant differences between the two VR therapies in any primary or secondary outcome measures at any timepoint, even though they had completely different mechanisms of action.

“However, the absence of a control group means the efficacy cannot be confirmed. Further mechanistic research and treatment development are needed,” commented the researchers. Findings of the THRIVE trial indicated that the development of immersive technologies for mental health would benefit from sustained research into the implementation of various techniques, including the necessary doses, and the different effects of techniques with different mechanisms of action.