TOPLINE:

Acute hospital care after the use of hallucinogens was associated with a sixfold higher risk for incident mania and a fourfold higher risk for bipolar disorder (BD) within 3 years in youth and adults than those not receiving this type of care, a new study showed.

METHODOLOGY:

• The population-based cohort study included more than 9 million individuals aged 14-65 years who were registered in the Ontario Health Insurance Plan in Canada between 2008 and 2022; more than 7000 received acute care after the use of hallucinogens.
• The primary outcome was an incident mania diagnosis in an acute care setting (emergency department [ED], general hospital, or mental health hospital). Secondary outcomes included an incident BD diagnosis in an acute care or outpatient setting.
• Comparisons were made between three groups: matched members of the general population without hallucinogen-related acute care, patients with incident all-cause acute care, and patients with incident cannabis-related acute care. The median follow-up duration was 7 years.
• Data on ED visits, hospitalizations, outpatient visits, and covariates were obtained from six individual-level databases. Covariates included age, sex, residence location, and healthcare encounters for mental health or other substance use in the past 5 years.

TAKEAWAY:

• Participants receiving hallucinogen-related acute care had a higher adjusted risk for incident mania within 3 years than individuals with no such hospitalization history but who have similar sociodemographics and history of prior use of substance or mental health care (hazard ratio [HR], 6.0; 95% CI, 3.3-10.8).
• They also had a higher adjusted risk for an incident BD diagnosis in acute care (HR, 3.75; 95% CI, 2.5-5.65) and in an outpatient or acute care setting (HR, 3.5; 95% CI, 2.85-4.3).
• Hallucinogen-related acute care was associated with a twofold higher risk for subsequent mania within 3 years than all-cause acute care visits after adjusting for demographics and history of mental health care (HR, 2.4; 95% CI, 1.9-3.15).
• The adjusted risk for subsequent mania did not differ significantly between individuals receiving hallucinogen-related or cannabis-related acute care (HR, 0.98).

IN PRACTICE:

“There has been a large increase in interest in the use of hallucinogens, often paired with therapy, to treat some mental health disorders. The current study helps highlight that hallucinogen use outside of trial settings may have important risks for a subset of people who use them,” investigator Daniel T. Myran, MD, North York General Hospital, Toronto, Ontario, Canada, said in a press release.

SOURCE:

The study was published online on December 2 in PLOS Medicine.

LIMITATIONS:

This study focused on individuals who had required urgent medical care after the use of hallucinogens and therefore did not generalize to the broader population of users. It lacked detailed information on patterns of use or specific drug types and relied on unvalidated diagnostic codes that may have led to misclassification. Additional limitations included residual confounding from unmeasured factors, outcomes that may have missed milder manic presentations, and potential reverse causation.

DISCLOSURES:

This study was funded by The Ottawa Hospital Academic Medical Organization innovation fund, Charité — Universitätsmedizin Berlin, and the Institute for Clinical Evaluative Science. One investigator reported receiving honoraria from and consulting for Angelini, AbbVie, Lundbeck, and Otsuka. The other investigators reported no relevant financial relationships.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.