Since about 2000, non-medical use and harms (e.g., morbidity, mortality) related to prescription opioids (POs) have emerged as a major substance use and public health problem in North America, including Canada[1, 2]. While key facets of this very problem are solidly documented in the United States (US), the only country in the world with a higher overall PO consumption (in Defined Daily Doses, DDD) per capita than Canada, relevant indicator data for Canada have been available only selectively, in part due to inadequate monitoring systems[1, 3, 4].
The most comprehensive Canadian data on NMPOU and PO-related harms come from Ontario, its most populous province. There are two reasons for this: overall PO consumption rates (a known determinant of levels of PO-related harms) are higher in Ontario than in most other provinces, and it has the most comprehensive monitoring data available[5, 6]. Specifically, recent Ontario data have indicated high levels of non-medical prescription opioid use (NMPOU) in general adult (5.9%; 2010/11) and secondary student (15.5%; 2011), as well as key marginalized (e.g., aboriginal on reserves, street drug users) populations[1, 7, 8]. Furthermore, there have been substantive increases in PO-related substance use treatment admissions and increases in PO-related accidental mortality since about 2000[1, 2, 9]. In addition, extensive variations of PO prescribing, including possible over-prescribing, associated with elevated morbidity and mortality risks have been documented in the Ontario population[10, 11].
While Canada, unlike countries like the US or Australia, yet remains without a national strategy targeting the problem of NMPOU and PO-related harms, various governmental and non-governmental entities in Ontario have implemented a number of large-scale interventions aiming to reduce these problem phenomena in the past couple of years. For example, in 2010, the Ontario College of Physicians and Surgeons (CPSO) issued a report containing numerous recommendations for improved regulatory control, clinical practice guidelines, and interventions related to POs with the aim of reducing the “opioid public health crisis” in Ontario. In November 2010, the Ontario government passed the ‘Narcotics Safety and Awareness Act’ (NSAA) as the legal foundation of its new provincial ‘Narcotics Strategy’ launched in 2011. A core feature of the NSAA was the implementation of a prescription monitoring program (PMP) centrally collecting information on POs dispensed by prescribers and patients. PMPs have been in place in most US states and Canadian provinces (but not Ontario) and are associated with reduced PO dispensing levels, albeit their effects on PO abuse or harms are not clearly evidenced[14, 15]. In early 2012, the province delisted ‘Oxycontin’ (oxycodone) – a potent PO substance associated with an extensive share of NMPOU and PO-deaths—which accounted for 25% (in Defined Daily Doses per population) of PO dispensing in 2010 in Ontario from the province’s formulary, triggering a substantive reduction of its clinical use and availability. These initiatives have been accompanied by extensive media reporting on the extent of NMPOU and PO-related harms effects on individual and public health[17, 18].
The above interventions mostly occurred on an ad-hoc basis, and commentators have emphasized the need for systematic evaluations of their effects on reducing NMPOU and harms in Ontario, in the interest of science, evidence-based policy and public health[16, 19]. Important markers for such evaluative efforts are indicators of both any PO use and NMPOU among adults. These specific indicators are assessed for Ontario by the ‘Centre for Addiction and Mental Health (CAMH) Monitor’ (CM), a long-standing survey on substance use and health indicators of the Ontario general adult population.