Does Cannabis Use Affect Treatment Outcome in Bipolar Disorder?

Abstract

Research suggests that cannabis use affects negatively on onset and outcome of schizophrenia, but less is known about possible effects in mood disorders. Bipolar in- and outpatients (N = 3459) were enrolled in an observational study. The influence of cannabis exposure on clinical and social treatment outcome measures was examined over the course of 1 year, as well as the effects on these associations of third mediating variables. Over 12 months of treatment, cannabis users exhibited less compliance and higher levels of overall illness severity, mania, and psychosis compared with nonusers. Additionally, cannabis users experienced less satisfaction with life and had a lower probability of having a relationship compared with nonusers. There was little evidence that cannabis-outcome associations were mediated by third variables. An independent impact of cannabis use on psychopathologic outcomes in patients with bipolar disorder was apparent, whereas the impact on social outcomes was modest.

Cannabis use and mania symptoms: A systematic review and meta-analysis

“…van Rossum et al (2009) explored the association between cannabis use and mania symptoms over the course of a year in a very large sample (N=3,426) of bipolar in-and outpatients. Mania symptoms were assessed using the Clinical Global Impression Bipolar (CGB-BP) mania scale and rated for severity on a seven point index (yielding a total mania symptom score) at baseline, 12 weeks, 6 months and 1 year.…”

“…Bipolar disorder is a complex disease with extensive and diverse symptom clusters (van Rossum et al, 2009) including manic and depressive phases. In terms of cannabis use, associations with manic phases appear especially likely DelBello, 2000, Sarkar et al, 2003).…”

Cannabis e humor

“…De um modo geral, parece que o uso de substâncias psicoativas em bipolares pode estar associado a uma série de características negativas, como dificuldade na recuperação dos sintomas afetivos, maior número de internações, piora na adesão ao tratamento, risco aumentado de suicídio, agressividade e a uma pobre resposta ao lítio 13,[19][20][21][22][23] . No estudo de van Rossum et al, no qual mais de três mil sujeitos foram acompanhados por um período de um ano, os prejuízos clínicos foram bem mais evidentes do que os prejuízos sociais 20 .…”

“…No estudo de van Rossum et al, no qual mais de três mil sujeitos foram acompanhados por um período de um ano, os prejuízos clínicos foram bem mais evidentes do que os prejuízos sociais 20 . Além disso, os bipolares que fizeram uso de cannabis tiveram maiores índices de uso de outras substâncias ilícitas.…”

“…Esta ideia é reforçada pela observação de que alguns pacientes poderiam ter a sensação de uma melhora no convívio social ao fazerem uso de maconha 20,25 .…”