Co-occurring cannabis use disorders and nicotine dependence was associated with several psychosocial problems with public health relevance. Relative to adults with nicotine dependence only, adults with co-occurring cannabis use disorders and nicotine dependence were almost twice as likely to drive under the influence of alcohol and three times as likely to be involved in partner violence. Relative to both those with nicotine dependence only and those with cannabis use disorders only, adults with co-occurring cannabis use disorders and nicotine dependence engaged in almost twice as many antisocial behaviors. Thus, co-occurring cannabis use disorders and nicotine dependence are associated with risky and harmful behaviors that could have an untoward impact on others. However, because individuals with co-occurring cannabis and tobacco use are more likely to meet diagnostic criteria for cannabis use disorders and nicotine dependence (Peters et al., 2012), it is possible that the associations with risky behaviors may be due to the greater severity of each disorder, not the comorbidity of the disorders per se. Although the current study cannot tease apart these relationships, results speak to the need to
