In a Cox proportional hazards model (Table 2), the contributions of age, gender, smoking status, lifetime history of cannabis use and lifetime history of alcohol use were examined. Mortality risk was significantly increased in males (Hazard Ratio (HR)=2.2, p=0.02), older ages (35–55 years versus <35 years) (HR=2.3, p=0.01), but decreased in cannabis users (HR=0.5, p=0.04). Alcohol was not predictive of mortality in the cox model (HR=0.8, p=0.29). There were no significant interactions between cannabis and alcohol use (χ2=0.3, df=1, p=0.61), or between use of either substance and age.
