Characteristics and predictors of health problems from use among high-frequency cannabis users in a Canadian university student population

Aims: Assess key cannabis use, risk and outcome characteristics among high-frequency cannabis users within a university student sample in Toronto, Canada. Methods: N = 134 active universities students (ages of 18-28) using cannabis at least three times per week were recruited by mass advertisement, telephone-screened and anonymously assessed by an interviewer-administered questionnaire. Relevant descriptive statistics are presented; subsequent univariate and multivariate logistic regression analyses (MLRA) identified independent predictors of experiencing physical or mental health problems. Findings: The majority of respondents used cannabis >5 years, almost daily and >1 times/day, socially and medically on occasion. In past 30 days, 79% used cannabis by deep inhalation, 38% drove a car after use, 45% had difficulty controlling or limiting use and 52% experienced negative mental/physical health effects, with few respondents reporting any past treatment. The MLRA identified 'difficulty controlling or limiting use' (OR = 3.40, 95% CI = 1.58-7.30), 'non-white ethnicity' (OR = 2.78, 95% CI = 1.13-6.83), and 'living with others' (OR = 2.37, 95% CI = 1.02-5.55) as independent predictors (p < 0.01) of negative health problems. Conclusions: Our sample was characterized by several use-related risks and problems, which may result in long-term burden of disease. University environment may offer suitable settings for targeted interventions. Determinants of future cannabis use and problems should be assessed in this population.