Impact of Cannabis Use on Long-Term Remission in Bipolar I and Schizoaffective Disorder

Abstract

ObjectiveTo investigate the impact of regular cannabis use on long-term remission of mood symptoms in bipolar spectrum disorders.MethodsThe 24-month prospective observational study included patients (n=239) with bipolar I disorder and schizoaffective disorder, bipolar type. Participants were classified as regular cannabis users (three times or more per week) or non-users. The primary outcome measure was the achievement of remission on the evaluations during the 24 months.ResultsOf the 234 participants for whom data was available, 25 (10.7%) were regular cannabis users, and the group comprised significantly more males than females. In the total population, cannabis use was significantly associated with decreased likelihood of remission during the 24-month follow-up period. Subgroup analyses showed that cannabis use was significantly associated with lower remission rates on the Hamilton Depression Rating Scale in females (n=139) and patients prescribed mood stabilizers alone (n=151), whereas in males (n=95) and patients prescribed olanzapine and/or a mood stabilizer (n=83), cannabis use was significantly associated with lower remission rates on the Young Mania Rating Scale. Remission rates were lowest in the concurrent cannabis and tobacco smoking group (n=22) followed by the tobacco smoking only group (n=97), and the non-smoker group (n=116). The post-hoc analysis revealed that all remission rates were significantly lower in the concurrent cannabis and the tobacco smoking group compared to the non-smoker group.ConclusionCannabis use negatively affects the long-term clinical outcome in patients with bipolar spectrum disorders. A comprehensive assessment and integrated management of cannabis use are required to achieve better treatment outcomes for bipolar spectrum disorders.

Areas of controversy in neuroprogression in bipolar disorder

“…Additionally, a machine learning study revealed that psychiatric comorbidities are associated with suicide attempts in patients with BD . Furthermore, alcohol use and cannabis use in patients with BD were associated with lower remission rates , higher severity of mood episodes, and functional impairment . A recent systematic review reported that patients with BD with a current or history of comorbid alcohol use disorder show more severe neurocognitive impairments especially in verbal memory and executive cognition .…”

Pros and Cons of Medical Cannabis use by People with Chronic Brain Disorders

“…Cannabis use in patients with bipolar also further increases the risk for suicide [ 159 ]. A prospective study showed that cannabis use is associated with a decrease in long-term remission for bipolar disorder [ 164 ]. A large epidemiological study indicated that cannabis use increases the risk for manic symptoms [ 165 ].…”

Medical cannabis&nbsp;‒&nbsp;the Canadian perspective<p class="MsoNormal">&nbsp;</p>

“…Recently, Kim et al found that cannabis use was significantly associated with lower rates of remission of bipolar spectrum patients over a 2-year follow-up period. 78 Studies have also found an association between cannabis misuse and earlier onset of bipolar disorder. 79 Thus, the use of low-THC content strains is recommended for these patients.…”