LSD use in the United States: Examining user demographics and their evolution from 2015-2019

Weleff and colleagues situate their study in the context of a documented upward trend in LSD use in the United States and renewed public and scientific interest in psychedelic therapies. Earlier clinical research suggested possible therapeutic applications of LSD for conditions such as alcohol and opioid use disorders and cancer-associated psychological distress, but human research largely ceased after LSD became illegal in 1971. Recent decades have seen a revival of psychedelic research and some local decriminalisation efforts, but contemporary epidemiological descriptions of LSD users are limited. The paper therefore aims to characterise past-year LSD users in the US using nationally representative survey data from 2015 to 2019 and to examine how user demographics and correlates of use have changed across that period. The objective is to identify demographic, behavioural, and attitudinal factors associated with past-year use and to evaluate temporal trends within the user population.

The investigators analysed pooled data from the National Survey on Drug Use and Health (NSDUH) for survey years 2015–2019. NSDUH is an annual, in-person survey of non-institutionalised civilians age 12 and older in all 50 states and the District of Columbia; institutionalised populations (for example, people in prison, hospitals, or nursing homes) are excluded. The primary outcome was an NSDUH-imputed variable indicating past-year LSD use; the extracted text states there were no missing data for this outcome. The authors excluded 2020 data due to COVID-19–related methodological changes in that year. Analyses accounted for the complex survey design using respondent weights, replicate weights, and variance strata; because five years of data were pooled, the respondent weight was divided by five. Continuous variables were summarised as weighted medians with interquartile ranges and compared using log-transformed linear regression. Categorical variables were reported as weighted percentages with 95% confidence intervals and compared using Rao–Scott chi-square tests. Univariable associations were adjusted for survey year, age group, gender, education, employment status, marital status, race/ethnicity, metropolitan area, a combined religious-importance/decision-making variable, and criminal arrest history. Multivariable logistic regression models were constructed to estimate adjusted odds ratios for past-year LSD use. Three separate multivariable models were fitted: respondents under age 18, respondents age 18 and older, and an all-ages model. Variables for multivariable modelling were chosen from factors previously associated with LSD use and those showing association in univariable analyses; models were simplified to address multicollinearity and confounding. Some variables were excluded from multivariable modelling for reasons noted in the text (for example, needle use was excluded due to low incidence; pregnancy was excluded because it was asked only of female respondents). Statistical significance was assessed at p<0.05 and analyses were performed in SAS 9.4. The study received approval from the Cleveland Clinic Institutional Review Board.

The unweighted analytic sample comprised N=282,768 respondents, of whom 3,632 reported past-year LSD use. The pooled weighted prevalence of past-year use was 0.77% (95% CI 0.72–0.81%). From 2015 to 2019 past-year LSD use rose by 47%, from 0.59% to 0.87% (p<0.0001). Year-to-year relative increases were largest between 2015–2016 (20.3%) and 2016–2017 (14.1%), with smaller rises thereafter. On univariate comparisons, past-year LSD users differed from non-users across many demographic and behavioural characteristics (most differences p<0.001). Users were more likely to be male (67.9% vs 48.3%), aged 18–25 (56.4% vs 12.3%), White (71.1% vs 62.8%), lesbian/gay/bisexual (18.0% vs 4.9%), living in large metropolitan areas (59.4% vs 55.9%), never married (85.7% vs 28.1%), without children under 18 at home (92.8% vs 73.3%), employed part time or unemployed (35.1% vs 17.3% among age 18+), and lower income (25.4% of users < $20,000/year vs 16.1% of non-users). Higher proportions of users reported past-year serious psychological distress (36.3% vs 11.1%) and past-year suicide attempt (3.9% vs 0.54%). Past-year hallucinogen use disorder and lifetime injection drug use were also more common among past-year LSD users (6.6% vs 0.06% for hallucinogen use disorder; 7.1% vs 1.6% for needle use). Users reported substantially greater perceived ease of obtaining LSD (53.0% vs 12.8%) and lower perceived risk for various substance use behaviours (for example, reporting no risk in trying LSD once or twice: 34.9% of users vs 3.2% of non-users). Temporal changes within the user population included an increasing share of users aged 26–34, which rose from 16.3% in 2015 to 26.5% in 2019 (p<0.0001). The proportion of past-year users who were married increased from 5.7% to 10.1% (p<0.0001), and the proportion of respondents reporting pregnancy (among female respondents) rose from 1.1% to 2.1% across the same period (p<0.0001). The authors report a statistically significant rise in past-year LSD use among lifetime users of methamphetamine (p=0.04); the extracted text contains inconsistent percentage figures for specific years, so the exact year-specific percentages are not clearly reported here. Multivariable models identified a consistent set of factors associated with increased adjusted odds of past-year LSD use. In the all-ages model these included more recent survey year, younger age (age 12–17), part-time employment, non-Hispanic Asian race, religious beliefs that were unimportant and non-influential, history of having sold illegal drugs, lifetime use of other substances (alcohol, marijuana, stimulants, sedatives, or other hallucinogens), being approached by someone selling drugs in the past month, lower perceived risk of trying LSD, and easier reported access to LSD (all p-values <0.05 for listed factors). For respondents under 18, higher odds were similarly associated with non-influential religious beliefs, overnight hospital admission in the past year, lifetime use of multiple substance classes, recent approach by someone selling drugs, lower perceived risk, and easier access. Among respondents 18 and older, the over-18 model additionally identified past-year suicide attempt as associated with increased odds of past-year LSD use (p=0.01). Factors associated with decreased odds across models included marriage, female gender, household income more than twice the federal poverty threshold, and having children under 18 at home. The text notes that several candidate variables were excluded from multivariable models for reasons such as collinearity, low incidence, or lack of association.

Weleff and colleagues interpret their findings as evidence of a meaningful increase in past-year LSD use in the US from 2015–2019, while emphasising that absolute prevalence remains low relative to common substances such as alcohol, tobacco, or marijuana. Despite the rise in use, there was no statistically significant increase in the proportion of people with lifetime hallucinogen use disorder reporting past-year LSD use, which the authors suggest may indicate that other hallucinogens contribute more to that diagnosis than LSD does. The multivariable results are presented as a profile of higher-risk users: younger, unmarried men without children, with prior polysubstance exposure, part-time employment and lower income, reduced religious influence on decisions, low perceived risk of LSD, and easier reported access. However, the authors highlight an important and unresolved signal linking past-year LSD use and past-year suicide attempt among adults; because NSDUH does not capture temporal sequencing or motivations for use, they explicitly state that causality cannot be inferred and that some individuals might be using LSD to self-treat mental illness whereas others might be vulnerable to adverse outcomes after use. The discussion places the religion-related finding in the context of prior smaller studies, noting differences in measurement (religious versus spiritual constructs), cultural contexts, and analytic adjustments that could explain conflicting results. The authors also point to changing demographic patterns over the study period — increases among people aged 26–34, married individuals, and pregnant respondents — as possible early indicators of growing social acceptance of LSD. They note a rise in co-occurrence with methamphetamine use but acknowledge uncertainty about whether use is simultaneous and the potential implications for adverse experiences. Strengths cited include the large, nationally representative survey sample and multi-year pooled design. Limitations acknowledged by the authors are retrospective self-report (with potential underreporting despite NSDUH validation against drug testing), exclusion of institutionalised populations (which comprise about 3% of the US population), and lack of NSDUH items on dose, frequency of exposures, setting, and reasons for LSD use. The authors emphasise these constraints when interpreting the findings and call for further research to clarify temporal relationships and potential harms such as the association with suicide attempts.

From pooled 2015–2019 NSDUH data, past-year LSD use in the US increased by 47% but remained uncommon in absolute terms. The increase in use was associated with lower perceived risk and greater reported access to LSD. Non-users generally judged regular LSD use as riskier than regular alcohol or marijuana use but slightly less risky than regular cocaine or heroin use. Observed demographic shifts — more users aged 26–34, more married users, and a higher proportion of pregnant respondents reporting past-year LSD use — are interpreted by the authors as possible signs of growing social acceptance. On multivariable analysis the study found no associations between past-year LSD use and unemployment, arrest history, past-year psychological distress, or sexually transmitted infections, which the authors take to suggest that LSD has not substantially contributed to broader public health problems in the US during the study period.