Cigarette smoking and its relationship to mood disorder symptoms and co-occurring alcohol and cannabis use disorders following first hospitalization for bipolar disorder.

OBJECTIVES: Cigarette smoking is highly prevalent among individuals with bipolar disorder (BD) and may adversely affect symptoms of the disorder, as well as the co-occurrence of other substance use disorders. However, anecdotal reports suggesting that smoking cessation caused a worsening of mood in smokers with BD have raised concerns about quitting. In the present study, we prospectively evaluated the course of BD, alcohol use disorders, and cannabis use disorders in relation to smoking and examined the relationship between smoking abstinence and changes in mood.
METHODS: Participants (N = 161) were adolescents (n=80) and adults (n = 81) with bipolar I disorder who were hospitalized for their initial mixed or manic episode. Participants were followed up to eight years post-hospitalization (median follow-up = 122 weeks) as part of a naturalistic, observational study of the longitudinal course of BD and substance use.
RESULTS: The course of BD symptoms in the 12 months following index hospitalization did not differ by smoking status in either the adolescent or the adult subsample. Among adolescents, smoking was associated with an increased risk of having a cannabis or alcohol use disorder, almost all of which were new-onset disorders, in the year following first hospitalization. Neither adolescents nor adults who were abstinent from smoking for at least two months experienced significant increases in depressive or manic symptoms.
CONCLUSIONS: Although cigarette smoking did not predict a worse course of BD, smoking was associated with an increased risk of developing alcohol and cannabis use disorders in adolescents with BD. Importantly, these data provide no evidence to suggest that abstinence from smoking is associated with worsening symptoms of depression or mania in the short term.