I wondered when the scare papers would start kicking in.
I’m surprised it has taken so long.
Abstract
Background: Although clinical trials involving psychedelic-assisted psychotherapy have not observed short-term increases in the risk of death, limited data exist on mortality associated with hallucinogen use outside of controlled trial settings. We sought to determine whether people with an emergency department visit or hospital admission involving hallucinogen use were at increased risk of all-cause death compared with the general population and with people with acute care presentations involving other substances.
Methods: We conducted a retrospective cohort study using linked health administrative data on all people aged 15 years and older living in Ontario, Canada, from 2006 to 2022. We compared overall and cause-specific mortality between members of the general population and people with incident acute care (an emergency department visit or hospital admission) involving hallucinogens and other substances.
Results: We included 11 415 713 people; 7953 (0.07%) had incident acute care involving hallucinogens. In a matched analysis with 77 101 people with a median follow-up of 7 (interquartile range 3–11) years, acute care involving hallucinogens was associated with a 2.6-fold (hazard ratio [HR] 2.57, 95% confidence interval [CI] 2.09–3.15) increased all-cause mortality within 5 years (n = 482, absolute risk 6.1%) relative to the general population (n = 460, absolute risk 0.6%). Analyses excluding people with comorbid mental or substance use disorders showed similar elevations in mortality risk for acute care involving hallucinogens relative to the general population (HR 3.25, 95% CI 2.27–4.63). People with acute care involving hallucinogens were at a significantly elevated risk of death by unintentional drug poisoning (HR 2.03, 95% CI 1.02–4.05), suicide (HR 5.23, 95% CI 1.38–19.74), respiratory disease (HR 2.46, 95% CI 1.18–5.11), and cancer (HR 2.88, 95% CI 1.61–5.14) relative to the general population.
Interpretation: Requiring hospital-based care for hallucinogen use was associated with increases in risk of death relative to the general population, particularly from suicide. These findings should be considered in clinical and policy decision-making, given the increasing use of hallucinogens and associated problematic use.
The use of hallucinogens has been rapidly increasing since the mid-2010s globally, and particularly in the United States and Canada.1–3 In the US, among people aged 19–30 years, self-reported hallucinogen use in the past year more than doubled from 3.8% in 2013 to 8.9% in 2023.4 Hallucinogens are a group of substances that influence perception and mood and are broadly classified into dissociative drugs, including phencyclidine (PCP) and ketamine, and serotonergic hallucinogens (psychedelics), including psilocybin, lysergic acid diethylamide (LSD), dimethyltryptamine (DMT, or ayahuasca), and methylenedioxymethamphetamine (MDMA, or Ecstasy). Increasing interest in and use of hallucinogens may be related to promising clinical trials supporting the therapeutic potential of hallucinogens in mental and substance use disorders.5,6 Multiple randomized controlled trials suggest that psychedelic-assisted therapy may be effective for the management of alcohol use disorder, posttraumatic stress disorder, and treatment-resistant depression.7–12 However, there are concerns that hallucinogen use may also increase the risk of serious adverse events, including suicidality and death, particularly when used outside of supervised clinical settings and in populations with comorbid health conditions.13
Two studies in the US found no increased risk of all-cause death for people who reported ever having used hallucinogens or inhalants at baseline.14,15 A study of Swedish men registering for compulsory military service found no association between self-reported hallucinogen or inhalant use at age 18 years and mortality over the following 35 years.16 A study in the United Kingdom found no association between reported hallucinogen use in early adulthood and subsequent risk of death.17 Critically, studies to date have had small sample sizes (the largest included fewer than 1000 people who reported hallucinogen use) that may be underpowered to detect changes in risk of death. Additionally, studies that characterized exposure to hallucinogens were limited to less clinically relevant measures of hallucinogen use (e.g., lifetime use, single-time use at age 18 yr), relying on self-report and combining hallucinogens with other substances. In addition, study reports lacked details on the cause of death and adjusted for a limited number of potential confounders. Overall, despite large increases in the prevalence of hallucinogen use, we found no high-quality evaluations of whether hallucinogen use may increase the risk of death.
Our objective was to use contemporary population-level data to address current gaps in the literature on the association between hallucinogen use and mortality. We sought to establish whether people with an emergency department visit or hospital admission (collectively, acute care) involving hallucinogen use were at increased risk of all-cause death compared with the general population and people with acute care involving other substances.
The paper-
