Associations between lifetime classic psychedelic use and markers of physical health

Abstract

Background
In recent years, there has been significant research on the mental health effects of classic psychedelic use, but there is very little evidence on how classic psychedelics might influence physical health.

Aims
The purpose of the present study was to investigate the associations between lifetime classic psychedelic use and markers of physical health.

Methods
Using data from the National Survey on Drug Use and Health (2015-2018) with 171,766 (unweighted) adults aged 18 or above in the United States, the current study examined the associations between lifetime classic psychedelic use and three markers of physical health (self-reported overall health, body mass index, and heart condition and/or cancer in the past 12 months) while controlling for a range of covariates.

Results
Respondents who reported having tried a classic psychedelic at least once in their lifetime had significantly higher odds of greater self-reported overall health and significantly lower odds of being overweight or obese versus having a normal weight. The association between lifetime classic psychedelic use and having a heart condition and/or cancer in the past 12 months approached conventional levels of significance, with lower odds of having a heart condition and/or cancer in the past 12 months for respondents who had tried a classic psychedelic at least once.

Conclusion
The results of the present study suggest that classic psychedelics may be beneficial to physical health. Future research should investigate the causal effects of classic psychedelics on physical health and evaluate possible mechanisms.

Full text

https://doi.org/10.1177/0269881121996863
Journal of Psychopharmacology
2021, Vol. 35(4) 447 –452
© The Author(s) 2021
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DOI: 10.1177/0269881121996863
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Introduction
The effects of psychedelic drug use on human cognition and
behaviour have recently received significant scientific attention
(Rucker et al., 2018; Sessa, 2018). The research has been con-
ducted in controlled settings and has primarily focused on classic
psychedelics, which are a subclass of psychedelics, with little
evidence of physiological toxicity, known to act as agonists pri-
marily at 5-HT2A receptors (dos Santos et al., 2018; Johnson
et al., 2018; Winkelman, 2014). The three main classes of classic
psychedelics (tryptamines, lysergamides and phenethylamines)
are distinguished by unique chemical structures and neurochemi-
cal mechanisms (Szabo, 2015). Most notably, they include N,N-
dimethyltryptamine (DMT), the DMT-containing admixture
ayahuasca, psilocybin, lysergic acid diethylamide (LSD), mesca-
line, and the mescaline-containing cacti peyote and San Pedro
(Sexton et al., 2019a).
The evidence to date suggests that classic psychedelics have
immunomodulatory and anti-inflammatory properties (Flanagan
and Nichols, 2018; Frecska et al., 2016; Nichols, 2009; Szabo,
2015, 2019); carry low risk of adverse effects when administered
by health professionals in a safe and supportive environment
(Nutt and Carhart-Harris, 2020; Nutt et al., 2010; Rucker et al.,
2018); and can be effective in the treatment of depression, anxi-
ety and addiction (Aday et al., 2020; Carhart-Harris et al., 2016,
2018; Davis et al., 2020; Goldberg et al., 2020; Johnson et al.,
2014; Krebs and Johansen, 2012; Luoma et al., 2020). For exam-
ple, patients with treatment-resistant depression experienced
reductions in depressive symptoms after two oral doses of
psilocybin. There was no control group in the study, but the
depressive symptoms remained significantly reduced at 1 week,
3 months, and 6 months post-treatment (Carhart-Harris et al.,
2016, 2018). The patients were interviewed post-treatment and
many of them reported significant improvements in health behav-
iour (Watts et al., 2017), which suggests that classic psychedelic
use might induce behavioural changes favourable to physical
health.
While double-blind, randomized, placebo-controlled trials are
warranted to experimentally examine the effects of classic psych-
edelics on physical health, population studies can provide insight
into these knowledge gaps. The National Survey on Drug Use
and Health (NSDUH) has frequently been analyzed to provide
weighted estimates of the prevalence and associations of lifetime
classic psychedelic use in the United States. The findings have
varied from 13.4 to 13.6% of the adult population reporting life-
time classic psychedelic use (Hendricks et al., 2017; Johansen
and Krebs, 2015) and have consistently showed that lifetime
classic psychedelic users are more likely to be male, white,
Associations between lifetime
classic psychedelic use and markers
of physical health
Otto Simonsson1, James D Sexton2
and Peter S Hendricks3
Abstract
Background: In recent years, there has been significant research on the mental health effects of classic psychedelic use, but there is very little
evidence on how classic psychedelics might influence physical health.
Aims: The purpose of the present study was to investigate the associations between lifetime classic psychedelic use and markers of physical health.
Methods: Using data from the National Survey on Drug Use and Health (2015-2018) with 171,766 (unweighted) adults aged 18 or above in the United
States, the current study examined the associations between lifetime classic psychedelic use and three markers of physical health (self-reported overall
health, body mass index, and heart condition and/or cancer in the past 12 months) while controlling for a range of covariates.
Results: Respondents who reported having tried a classic psychedelic at least once in their lifetime had significantly higher odds of greater self-
reported overall health and significantly lower odds of being overweight or obese versus having a normal weight. The association between lifetime
classic psychedelic use and having a heart condition and/or cancer in the past 12 months approached conventional levels of significance, with lower
odds of having a heart condition and/or cancer in the past 12 months for respondents who had tried a classic psychedelic at least once.
Conclusion: The results of the present study suggest that classic psychedelics may be beneficial to physical health. Future research should investigate
the causal effects of classic psychedelics on physical health and evaluate possible mechanisms.
Keywords
Classic psychedelics, psilocybin, LSD, health, body mass index, cancer, heart disease
1 Department of Sociology, University of Oxford, Oxford, UK
2 Department of Brain Sciences, Imperial College London, London, UK
3 Department of Health Behavior, University of Alabama at Birmingham,
Birmingham, USA
Corresponding author:
Otto Simonsson, Department of Sociology, University of Oxford, 42–43
Park End Street, Oxford, OX1 2JD, UK.
Email: otto.simonsson@trinity.ox.ac.uk
996863JOP0010.1177/0269881121996863Journal of PsychopharmacologySimonsson et al.
research-article2021
Short Report

448 Journal of Psychopharmacology 35(4)
younger than 65 years of age, and have higher income and educa-
tion (Johansen and Krebs, 2015; Krebs and Johansen, 2013a,
2013b). The results have also shown that lifetime classic psyche-
delic use is associated with lower odds of psychological distress
and suicidality (Hendricks et al., 2015), lower odds of opioid
abuse and dependence (Pisano et al., 2017), and lower odds of
criminal behavior (Hendricks et al., 2017), which broadly mirrors
the research that suggests therapeutic efficacy of classic psyche-
delics as well as the low risk of harm to self and others that clas-
sic psychedelics have been ascribed by drug experts in the United
Kingdom (Nutt et al., 2010), the Netherlands (Van Amsterdam
et al., 2010) and Australia (Bonomo et al., 2019). There have, in
other words, been several population studies on lifetime classic
psychedelic use, but the association between lifetime classic psy-
chedelic use and physical health remains unexplored.
Using pooled data from the NSDUH (2015–2018), the present
study seeks to investigate the association between lifetime classic
psychedelic use and three markers of physical health (self-
reported overall health, body mass index (BMI), and heart condi-
tion and/or cancer in past 12 months). We hypothesized that
lifetime classic psychedelic use would be associated with better
physical health status.
Materials and methods
Data and population
The NSDUH is an annual survey designed to measure the preva-
lence of substance use and mental health issues in the United
States. The present study used pooled data from the NSDUH sur-
vey years 2015 to 2018, which were weighted to reflect the civil-
ian noninstitutionalized population and contained responses from
171,766 (unweighted) adults aged 18 or above. The NSDUH
sampling and questionnaire methodology are described on their
website: https://nsduhweb.rti.org/respweb/about_nsduh.html
Variables
The dependent variables were self-reported overall health (vari-
able HEALTH2 recoded; 1 = Fair/Poor, 2 = Good, 3 = Very
Good, 4 = Excellent), BMI (variable BMI2 recoded per National
Institute of Health (NIH) guidelines (National Heart, Lung, and
Blood Institute (NHLBI) 1998): 1 = Underweight (<18.5), 2 =
Normal Weight (18.5–25), 3 = Overweight (25–30), 4 = Obesity
– Class 1 (30–35), 5 = Obesity – Class 2 (35–40), 6 = Extreme
Obesity – Class 3 (>40)), and heart condition and/or cancer in
past 12 months (variables HRTCONDYR and CANCERYR
combined such that a ‘yes’ response to either variable was coded
as 1 = Yes whereas a ‘no’ response to both variables was coded
as 0 = No).
The independent variables were DMT (code 616 from varia-
bles HALLUCOT1, HALLUCOT2, HALLUCOT3, HALLU-
COT4 and HALLUCOT5), ayahuasca (an entheogenic brew that
contains DMT; code 6103 from variables HALLUCOT1,
HALLUCOT2, HALLUCOT3, HALLUCOT4 and HALLU-
COT5), psilocybin (variable PSILCY2 = 1), LSD (variable lsd-
flag = 1), mescaline (variable MESC2 = 1), and peyote or San
Pedro (cacti that contain mescaline; variable PEYOTE2 = 1 or
code 6077 from variables HALLUCOT1, HALLUCOT2,
HALLUCOT3, HALLUCOT4 and HALLUCOT5). Respondents
reporting that they had ever, even once, used any of the above
classic psychedelics were coded as positive for lifetime classic
psychedelic use, whereas those indicating that they had never
used any of these substances were coded as negative. The ques-
tion in the NSDUH concerning use of DMT, alpha-methyl-
tryptamine (AMT) and 5-methoxy-N, N-diisopropyltryptamine
(5-MeO-DIPT) (variable DAMTFXFLAG: ‘Have you ever, even
once, used any of the following: DMT, also called dimethyl-
tryptamine, AMT, also called alpha-methyltryptamine, or Foxy,
also called 5-MeO-DIPT?’) was not included, because neither
AMT nor 5-MeO-DIPT are classified as classic psychedelic and
DMT use alone could not be determined from the question.
The control variables were age in years (variable CATAG6;
18–25, 26–34, 35–49, 50–64 or 65 or older); sex (variable
IRSEX; male or female); sexual orientation (variable
SEXIDENT; heterosexual, lesbian or gay, bisexual); ethnoracial
identity (variable NEWRACE2; non-Hispanic White, non-His-
panic African American, non-Hispanic Native American/Alaska
Native, non-Hispanic Native Hawaiian/Pacific Islander, non-
Hispanic Asian, non-Hispanic more than one race or Hispanic);
educational attainment (variable IREDUHIGHST2; 5th grade or
less, 6th grade, 7th grade, 8th grade, 9th grade, 10th grade, 11th
or 12th grade completed, High school diploma/GED, some col-
lege credit but no degree, Associate’s degree, College degree
or higher), annual household income (variable INCOME; less
than US$20,000, US$20,000–49,999, US$50,000–74,999 or
US$75,000 or more); marital status (variables IRMARITSTAT
and IRMARIT recoded; married, divorced/separated, widowed
or never married); self-reported engagement in risky behaviour
(variable RSKYFQTES recoded; never, seldom, sometimes
or always), lifetime cocaine use (variable COCFLAG; ever
used or never used), lifetime other stimulant use (variable
STMANYFLAG; ever used or never used), lifetime sedative use
(variable SEDANYFLAG; ever used or never used), lifetime
tranquilizer use (variable TRQANYFLAG; ever used or never
used), lifetime heroin use (variable HERFLAG; ever used or
never used), lifetime pain reliever use (variable PNRANYFLAG;
ever used or never used), lifetime marijuana use (variable
MRJFLAG; ever used or never used), lifetime phencyclidine
(PCP) use (variable PCPFLAG; ever used or never used), life-
time 3,4-methylenedioxymethamphetamine (MDMA/ecstasy)
use (variable ECSTMOFLAG; ever used or never used), lifetime
inhalant use (variable INHALFLAG; ever used or never used),
lifetime smokeless tobacco use (variable SMKLSSFLAG; ever
used or never used), lifetime pipe tobacco use (variable
PIPFLAG; ever used or never used), lifetime cigar use (variable
CGRFLAG; ever used or never used), lifetime daily cigarette use
(variable CDUFLAG; ever used or never used) and age of first
alcohol use (variable IRALCAGE recoded; less than 13 years of
age (Preteen), 13–19 years of age (Teen), more than 19 years of
age (Adult), or never used). These control variables were coded
as separate covariates and broadly mirror the covariates of prior
investigations (Hendricks et al., 2015; Sexton et al., 2019b),
except for lifetime smokeless tobacco, pipe tobacco, cigar and
daily cigarette use, as well as age of first alcohol use, which were
added to control for a lifetime history of major health risk factors
(Christensen et al., 2018; Hu et al., 2017; Inoue-Choi et al.,
2019a, 2019b; Levola et al., 2020). Lastly, a recoded version of
the Kessler Psychological Distress Scale (Kessler et al. 2002,

Simonsson et al. 449
2010) was also included as a control variable (variable
K6SCMON recoded into dichotomous variable), but only in the
ordered logistic regression model predicting self-reported overall
health (see below) to ensure that self-reported overall health was
not influenced by the mental health status of the respondents.
Statistical analyses
The present study used descriptive statistics to present an over-
view of lifetime use of classic psychedelics in the United States
(Table 1). Multiple regressions were used to calculate adjusted
odds ratios with 95% confidence intervals and examine the
unique associations between lifetime classic psychedelic use and
markers of physical health. Ordered logistic regression was used
to examine the association between lifetime classic psychedelic
use and self-reported overall health (Table 2); multinomial logis-
tic regression was used to examine the association between life-
time classic psychedelic use and BMI (Table 3); and logistic
regression was used to examine the association between lifetime
classic psychedelic use and having a heart condition and/or can-
cer in the past 12 months (Table 4).
The analyses used weights provided by the NSDUH, and the
control variables listed above were included as covariates in the
regression models to control for potential sources of confound-
ing. Insofar that the NSDUH is a nationally representative sur-
vey, there was no a priori rationale for identifying or removing
outliers. The NSDUH conducts statistical imputation and revi-
sion for missing values for select variables, denoted by ‘IMP’ or
‘IR’ prefixes. A number of constraints are put in place by the
NSDUH to ensure consistency in imputed values with non-miss-
ing values for use in multivariate analyses. In the present analy-
ses we did not conduct additional imputations beyond what the
NSDUH has already provided in their annual releases. All miss-
ing values were treated as missing. Additional information on the
NSDUH imputation procedure can be found in the ‘Statistical
Imputation’ section in the introduction of each annual codebook.
Finally, though there was no control for multiple comparisons,
exact p-values are reported to the fourth decimal place, which
allows for the application of conservative Bonferroni-type cor-
rections of the reader’s choosing (SAMHSA, 2019).
Results
Frequency distributions
Table 1 presents descriptive statistics of lifetime classic psyche-
delic users in the United States (2015–2018). As shown in the
table, approximately 14% of the sample reported lifetime classic
psychedelic use, which suggests that almost 34 million American
adults have used a classic psychedelic at least once in their life-
time, based on the population estimates from the NSDUH.
Multiple regressions
Table 2 presents results from the ordered logistic regression on
the association between lifetime classic psychedelic use and self-
reported overall health. As illustrated in the table, lifetime classic
Table 1. Lifetime classic psychedelic (DMT, Ayahuasca, Psilocybin,
LSD, Mescaline, Peyote or San Pedro) users in the United States
(2015–2018).
Responses % (95% CI) Population estimates
Ever used 13.8 (13.5–14.1) 33,925,666
Never used 86.2 (85.9–86.5) 211,912,497
Total 100 245,838,163
Note: The number of observations was 171,766 (unweighted). The percentages
have been weighted to reflect national estimates and have been rounded to the
closest decimal point.
Table 2. Lifetime classic psychedelic use and self-reported overall
health.
aOR (95% CI) p value N
Self-reported
overall health
1.08 (1.02–1.14) .0048 168,123
aOR: adjusted odds ratio; CI: confidence interval; N refers to unweighted counts
in the regression model; odds ratios are adjusted for age, sex, sexual orientation,
ethnoracial identity, educational attainment, annual household income, marital
status, self-reported engagement in risky behaviour, lifetime use of cocaine,
other stimulants, sedatives, tranquilizers, heroin, pain relievers, marijuana,
phencyclidine (PCP), 3,4-methylenedioxymethamphetamine (MDMA/ecstasy),
inhalants, smokeless tobacco, pipe tobacco, cigar and cigarettes daily, age of
first alcohol use, and past month psychological distress.
Table 3. Lifetime classic psychedelic use and body mass index.
aRRR (95% CI) p value N
Normal weight (Reference) 56,955
Underweight 0.93 (0.72–1.20) . 5753 3940
Overweight 0.86 (0.80–0.93) .0002 51,212
Obesity – Class 1 0.80 (0.74–0.87) <.0001 28,913
Obesity – Class 2 0.76 (0.69–0.83) <.0001 13,831
Extreme obesity – Class 3 0.78 (0.68–0.88) .0002 8926
aRRR: adjusted relative risk ratio; CI: confidence interval; N refers to unweighted
counts in each row; relative risk ratios are adjusted for age, sex, sexual orienta-
tion, ethnoracial identity, educational attainment, annual household income,
marital status, self-reported engagement in risky behaviour, lifetime use of co-
caine, other stimulants, sedatives, tranquilizers, heroin, pain relievers, marijuana,
phencyclidine (PCP), 3,4-methylenedioxymethamphetamine (MDMA/ecstasy),
inhalants, smokeless tobacco, pipe tobacco, cigar and cigarettes daily, and age of
first alcohol use.
Table 4. Lifetime classic psychedelic use and heart condition and/or
cancer in the past year.
aOR (95% CI) p value N
Heart condition and/or
cancer in the past year
0.89 (0.77–1.02) .0917 168,147
aOR: adjusted odds ratio; CI: confidence interval; N refers to unweighted counts
in the regression model; odds ratios are adjusted for age, sex, sexual orientation,
ethnoracial identity, educational attainment, annual household income, marital
status, self-reported engagement in risky behaviour, lifetime use of cocaine,
other stimulants, sedatives, tranquilizers, heroin, pain relievers, marijuana,
phencyclidine (PCP), 3,4-methylenedioxymethamphetamine (MDMA/ecstasy),
inhalants, smokeless tobacco, pipe tobacco, cigar and cigarettes daily, and age
of first alcohol use. Note: the odds ratios are similar when heart condition in
the past year and cancer in the past year are analyzed as separate dependent
variables (see Tables A1 to A3 in Appendix for more information).

450 Journal of Psychopharmacology 35(4)
psychedelic use was associated with significantly higher odds of
greater self-reported overall health.
Table 3 presents results from the multinomial logistic regres-
sion on the association between lifetime classic psychedelic use
and BMI. As illustrated in the table, lifetime classic psychedelic
use was associated with significantly lower odds of being over-
weight or obese as compared to having a normal weight.
Table 4 presents results from the logistic regression on the
association between lifetime classic psychedelic use and having
a heart condition and/or cancer in the past year. As illustrated in
the table, the association between lifetime classic psychedelic use
and having a heart condition and/or cancer in the past 12 months
approached conventional levels of significance, with lower odds
of having a heart condition and/or cancer in the past 12 months
for respondents who had tried a classic psychedelic at least once.
Discussion
The present study investigated the association between lifetime
classic psychedelic use and three markers of physical health (self-
reported overall health, BMI, and heart condition and/or cancer in
the past 12 months). Findings show that respondents who reported
having ever used a classic psychedelic had significantly higher
odds of greater self-reported overall health and significantly lower
odds of being overweight or obese as compared to having a nor-
mal weight. The association between lifetime classic psychedelic
use and having a heart condition and/or cancer in the past 12
months approached conventional levels of significance, with
lower odds of having a heart condition and/or cancer in the past 12
months for respondents who had tried a classic psychedelic at
least once. Taken together, these results suggest that classic psych-
edelics may have long-term beneficial effects beyond improved
mental health.
While the acute transcendent experience occasioned by clas-
sic psychedelics may presumably induce long-term changes in
health behaviour that contribute to better physical health, it is
plausible that there are other key mechanisms through which
classic psychedelics could influence physical health, including
improvements on various indices of mental health beyond the
simple absence of psychological distress (e.g. increased prosoci-
ality, trait mindfulness and purpose in life; Griffiths et al., 2018;
Murphy-Beiner and Soar, 2020), many of which are well-known
risk factors for physical maladies (Chaddha et al., 2016; Germann,
2020; Hernandez et al., 2018); immunomodulatory and anti-
inflammatory effects of relevance to physical health (Flanagan
and Nichols, 2018; Frecska et al., 2013, 2016; Szabo, 2015,
2019; Szabo et al., 2014; Thompson and Szabo, 2020; Tourino
et al., 2013; Winkelman and Sessa, 2019); and high affinity to
receptor subtypes (e.g. serotonin 2A receptors) that are impli-
cated in the pathophysiology of different physical disorders
(Nichols, 2009; Thompson and Szabo, 2020). Future research is
needed to better understand potential causal pathways of classic
psychedelics on physical health.
There are several limitations with the present study that need
serious consideration before the results are interpreted. First, the
cross-sectional design of the study limits causal inference. The
analyses controlled for multiple sources of potential confound-
ing, but the associations might have been obscured by response
bias or latent variables that were not controlled for (e.g. a com-
mon factor predisposing one to classic psychedelic use may also
predispose one to healthy lifestyle behaviours including physical
activity). Second, the dataset did not contain information on fre-
quency of classic psychedelic use, dose used or context of use.
The present study could therefore not evaluate frequency, dose or
context-specific relationships between classic psychedelic use
and physical health markers. Third, it is also not possible to rule
out that classic psychedelic use might have caused harm on the
individual level, even if it did not obfuscate the population-level
associations. Fourth, given the potential importance of immu-
nomodulatory and inflammatory factors in the current study, it
would have been sensible to also control for regular anti-inflam-
matory drug (e.g. nonsteroidal anti-inflammatory drug (NSAID))
use, but assessment of this behaviour was not included in the
NSDUH. Fifth, BMI has been widely used as a screening tool for
overweight or obesity, but it does not account for details such as
fat distribution, which limits its utility as a marker of physical
health (Prentice and Jebb, 2001). Finally, it is noted that some
associations of lifetime classic psychedelic use were somewhat
modest in size (e.g. heart condition and/or cancer in the past
year). However, even modest effects can have substantial impacts
at the population level. For instance, considering approximately
1.2 million people die from heart disease or cancer every year in
the United States alone (Heron, 2019), even a small decrease
(e.g. 11%) in the prevalence of these illnesses could translate to
thousands of lives saved annually.
Conclusion
The psychedelic research to date has primarily focused on mental
health, but relatively little is known about how classic psyche-
delics might influence physical health. The findings in the pre-
sent study suggest that lifetime classic psychedelic use is
associated with higher odds of better physical health status,
which demonstrates the need for more rigorous research to better
understand potential causal pathways of classic psychedelics on
physical functioning.
Authors’ note
The current study was a secondary analysis of publicly available data
files and was exempt from review by the Research Ethics Committee of
the Department of Sociology (DREC) at the University of Oxford.
Author contributions
OS conceived of the study and was the primary author who cleaned data,
conducted analyses and drafted the manuscript summarizing the findings.
JDS commented on draft manuscripts and contributed meaningful exper-
tise to inform methodology and statistical analyses. PSH supervised and
commented on draft manuscripts.
Declaration of conflicting interests
PSH is on the scientific advisory board of Bright Minds Biosciences Ltd.,
Eleusis Benefit Corporation., and Silo Pharma Inc. JDS is the
Bioinformatics Director at Eleusis Benefit Corporation.
Funding
The author(s) received no financial support for the research, authorship,
and/or publication of this article.
ORCID iD
Otto Simonsson https://orcid.org/0000-0003-4197-7566

Simonsson et al. 451
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Appendix
Logistic regressions
Multinomial logistic regression
Table A1. Lifetime classic psychedelic use predicting heart condition
in the past year.
aOR (95% CI) p value N
Heart condition in the past year 0.90 (0.76–1.06) .2074 168,147
aOR: adjusted odds ratio; CI: confidence interval; N refers to unweighted counts
in each regression model; odds ratios are adjusted for age, sex, sexual orienta-
tion, ethnoracial identity, educational attainment, annual household income,
marital status, self-reported engagement in risky behaviour, lifetime use of co-
caine, other stimulants, sedatives, tranquilizers, heroin, pain relievers, marijuana,
phencyclidine (PCP), 3,4-methylenedioxymethamphetamine (MDMA/ecstasy),
inhalants, smokeless tobacco, pipe tobacco, cigar and cigarettes daily, and age of
first alcohol use.
Table A2. Lifetime classic psychedelic use predicting cancer in the
past year.
aOR (95% CI) p value N
Cancer in the past year 0.88 (0.68–1.14) .3329 168,147
aOR: adjusted odds ratio; CI: confidence interval; N refers to unweighted counts
in each regression model; odds ratios are adjusted for age, sex, sexual orienta-
tion, ethnoracial identity, educational attainment, annual household income,
marital status, self-reported engagement in risky behaviour, lifetime use of co-
caine, other stimulants, sedatives, tranquilizers, heroin, pain relievers, marijuana,
phencyclidine (PCP), 3,4-methylenedioxymethamphetamine (MDMA/ecstasy),
inhalants, smokeless tobacco, pipe tobacco, cigar and cigarettes daily, and age of
first alcohol use.
Table A3. Lifetime classic psychedelic use predicting heart condition
only, cancer only, and both heart condition and cancer in the past year.
aRRR (95% CI) p value N
No heart condition or cancer
(Reference)
161,036
Heart condition only in the
past year
0.89 (0.76–1.05) . 1752 5563
Cancer only in the past year 0.86 (0.67–1.11) .2452 1328
Both heart condition and
cancer in the past year
0.98 (0.43–2.25) .9681 220
aRRR: adjusted relative risk ratio; CI: confidence interval; N refers to unweighted
counts in each row; relative risk ratios are adjusted for age, sex, sexual orienta-
tion, ethnoracial identity, educational attainment, annual household income,
marital status, self-reported engagement in risky behaviour, lifetime use of co-
caine, other stimulants, sedatives, tranquilizers, heroin, pain relievers, marijuana,
phencyclidine (PCP), 3,4-methylenedioxymethamphetamine (MDMA/ecstasy),
inhalants, smokeless tobacco, pipe tobacco, cigar and cigarettes daily, and age of
first alcohol use.