703-844-0184 | Suboxone Doctor | Alexandria, Va 22306 | Call for an appointment – web based services available
High-intensity cannabis use is associated with retention in opioid agonist treatment: a longitudinal analysis
Background and Aims Cannabis use is common among people on opioid agonist treatment (OAT), causing concern for
some care providers. However, there is limited and conflicting evidence on the impact of cannabis use on OAT outcomes.
Given the critical role of retention in OAT in reducing opioid-related morbidity and mortality, we aimed to estimate the association
of at least daily cannabis use on the likelihood of retention in treatment among people initiating OAT. As a secondary
aim we tested the impacts of less frequent cannabis use. Design Data were drawn from two community-recruited
prospective cohorts of people who use illicit drugs (PWUD). Participants were followed for a median of 81 months (interquartile
range = 37–130). Setting Vancouver, Canada. Participants This study comprised a total of 820 PWUD
(57.8% men, 59.4% of Caucasian ethnicity, 32.2% HIV-positive) initiating OAT between December 1996 and May
2016. The proportion of women was higher among HIV-negative participants, with no other significant differences.
Measurements The primary outcome was retention in OAT, defined as remaining in OAT (methadone or
buprenorphine/naloxone-based) for two consecutive 6-month follow-up periods. The primary explanatory variable was
cannabis use (at least daily versus less than daily) during the same 6-month period. Confounders assessed included:
socio-demographic characteristics, substance use patterns and social–structural exposures. Findings In adjusted analysis,
at least daily cannabis use was positively associated with retention in OAT [adjusted odds ratio (aOR) = 1.21, 95% confidence
interval (CI) = 1.04–1.41]. Our secondary analysis showed that compared with non-cannabis users, at least daily
users had increased odds of retention in OAT (aOR = 1.20, 95% CI = 1.02–1.43), but not less than daily users (aOR = 1.00,
95% CI = 0.87–1.14).
Among people who use illicit drugs initiating opioid agonist treatment in Vancouver,
at least daily cannabis use was associated with approximately 21% greater odds of retention in treatment compared with
less than daily consumption.
Heavy Cannabis Use Might Affect Recovery from Opiate Use Disorder
Using cannabis at least daily is associated with better 6-month retention in a program of opioid replacement therapy.
Greater retention during treatment for opiate use disorder (OUD) reduces morbidity and mortality and predicts better outcomes. According to preclinical and clinical data, both tetrahydrocannabinol (THC) and cannabidiol (CBD) might reduce opioid withdrawal and pain. CBD is safe in humans and might reduce anxiety and craving for opioids. However, results have been mixed in several large observational studies of the relationship between cannabis use and OUD treatment retention. In another observational study, researchers followed 820 Canadian patients with OUD for a median of 81 months after initiation of opioid replacement therapy (methadone, 99%).
At baseline, daily heroin injections were reported by 44%, daily prescription opioids by 8%, and cannabis use by 49% (17% used cannabis daily). In two semiannual follow-ups, daily use (but not less than daily) was associated with a 20% greater odds of 6-month treatment retention than no cannabis use. Various analyses yielded similar results.
Despite these provocative findings, providers should not recommend cannabis to patients with OUD for several reasons: Of several large observational studies, this is the only one supporting a benefit for retention with cannabis use; in two others, cannabis users had worse outcomes. As an observational study, it may have unmeasured confounders. Cannabis use has several potential associated risks and harms, including psychotic disorder, cognitive impairment, and cannabis use disorder. Finally, the findings might be relevant only to patients on methadone; almost no participant received buprenorphine. That said, cannabis use is unlikely to be excessively detrimental to recovery from OUD. In light of the recent FDA approval of a cannabidiol-containing compound and its classification to Schedule 5, more studies should be performed soon to investigate the utility of CBD for treating substance use disorders.