Cannabis and other substance use was linked to worse COVID-19 outcomes but not higher death rates
Among 17,423 COVID-19 patients, cannabis, cocaine, sedative, and opioid use were each associated with more ICU admissions, ventilator use, and longer hospitalizations, but not increased mortality.
Quick Facts
What This Study Found
Cannabis, cocaine, sedative, and opioid use were each associated with increased ICU care, ventilatory support, more hospitalizations, and longer stays; substance use was not associated with increased mortality; no differences between methadone, buprenorphine, and other opioids.
Key Numbers
n=17,423 COVID-19 patients; cannabis, cocaine, sedative, and opioid use each significantly associated with ICU admission, ventilation, and longer hospitalization; no mortality increase; no difference between MOUD types.
How They Did This
Retrospective cohort using EHR data from a large urban hospital system; 17,423 COVID-19 positive patients (2020-2021); substance use identified from urine toxicology within 90 days; multivariable logistic regression controlling for age, sex, comorbidity, tobacco, and social disadvantage.
Why This Research Matters
Understanding how substance use affects COVID-19 severity can inform clinical management and resource allocation during future outbreaks.
The Bigger Picture
Substance use may increase COVID-19 morbidity through immune, pulmonary, and cardiovascular mechanisms, but the lack of mortality association suggests these patients can recover with appropriate care.
What This Study Doesn't Tell Us
Retrospective design; substance use identified by urine toxicology (may miss some users); single hospital system; cannot separate individual substance effects in polysubstance users.
Questions This Raises
- ?Which specific mechanisms link cannabis to worse COVID-19 morbidity?
- ?Does smoking route drive pulmonary complications?
- ?Would vaccination modify the substance-COVID interaction?
Trust & Context
- Key Stat:
- Substance use increased ICU and ventilator needs but not COVID-19 mortality
- Evidence Grade:
- Large cohort with objective substance detection (urine toxicology) and adjusted analyses, though retrospective design and single-system data limit generalizability.
- Study Age:
- Published 2025, data from 2020-2021
- Original Title:
- Effects of Buprenorphine, Methadone, and Substance Use on COVID-19 Morbidity and Mortality.
- Published In:
- Journal of addiction medicine, 19(2), 223-226 (2025)
- Authors:
- Christian, Nicholaus J, Zhou, Xin, Radhakrishnan, Rajiv(8)
- Database ID:
- RTHC-06223
Evidence Hierarchy
Looks back at existing records to find patterns.
What do these levels mean? →Frequently Asked Questions
Did cannabis use make COVID-19 worse?
Cannabis use was associated with more ICU admissions, ventilator needs, and longer hospitalizations, but not with higher death rates from COVID-19.
Did addiction medications affect COVID outcomes?
No. There were no significant differences between methadone, buprenorphine, and other opioids on COVID-19 outcomes.
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Cite This Study
https://rethinkthc.com/research/RTHC-06223APA
Christian, Nicholaus J; Zhou, Xin; Radhakrishnan, Rajiv. (2025). Effects of Buprenorphine, Methadone, and Substance Use on COVID-19 Morbidity and Mortality.. Journal of addiction medicine, 19(2), 223-226. https://doi.org/10.1097/ADM.0000000000001386
MLA
Christian, Nicholaus J, et al. "Effects of Buprenorphine, Methadone, and Substance Use on COVID-19 Morbidity and Mortality.." Journal of addiction medicine, 2025. https://doi.org/10.1097/ADM.0000000000001386
RethinkTHC
RethinkTHC Research Database. "Effects of Buprenorphine, Methadone, and Substance Use on CO..." RTHC-06223. Retrieved from https://rethinkthc.com/research/christian-2025-effects-of-buprenorphine-methadone
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.