Compared with controls, BD cases were 6.8 times [95% C.I. 5.41-8.52] more likely to report a lifetime history of cannabis use – 71.3% of the cases, compared with 26.8% of the controls. This association was not modified by sex (p=0.22), however, the association was somewhat less strong in African-American (O.R. 0.48, 95% C.I. 0.29-0.76) subjects and in those aged 18-34 years (O.R. 0.58, 0.34-0.98). The association between BD and lifetime cannabis use persisted even after adjusting for other forms of substance use (alcohol, nicotine, cocaine and other illicit drugs).
