Non-medical use of prescription opioids among Ontario adults: data from the 2008/2009 CAMH Monitor.

OBJECTIVE: There are indications that non-medical prescription opioid analgesics use (NMPOU) in the general population has increased in Canada in recent years; however, existing estimates have limitations. Thus our objectives are to determine prevalence and associated demographics of 1) prescription opioid analgesics (PO) use, 2) NMPOU, and 3) use of PO for intoxication purposes in the adult population in Ontario.

METHODS: Prevalence and the associations between sex, age, region, income, cigarette smoking, binge drinking, cannabis use and psychological distress with the above-noted types of PO use were assessed using data from the 2008 and 2009 samples (n = 2030) of the CAMH Monitor. The statistical significance of the associations for all types of PO use was tested through bivariate associations using chi-square tests, and a two-step logistic regression was performed to test if demographics are associated with NMPOU.

RESULTS: The prevalence of PO use was 21.3% (95% CI 19.1-23.4), and the prevalence of NMPOU was 2.0% (95% CI 1.2-2.8) of Ontario adults. There were no significant differences between men and women for either PO use or NMPOU. Bivariate associations indicated that NMPOU was associated with tobacco and cannabis use and psychological distress in men. Logistic regression showed a significant association between NMPOU and each of age, cannabis use, and psychological distress in men.

DISCUSSION: NMPOU is an emerging epidemic in Canada across all income and age groups, and is associated with other substance use and mental health problems. Improved survey designs are required for more accurate population estimates of NMPOU.