Prescription Opioid Use, Harms and Interventions in Canada: A Review Update of New Developments and Findings since 2010.

BACKGROUND Canada has featured the second-highest levels of prescription opioid (PO) use globally behind the United States, and reported extensive PO-related harms (e.g., non-medical PO use [NMPOU], PO-related morbidity and mortality). A recent comprehensive review synthesized key data on PO use, PO-related harms, and interventions in Canada, yet a substantive extent of new studies and data have emerged. OBJECTIVE To conduct and present a comprehensive review update on PO use, PO-related harms, and interventions in Canada since 2010. STUDY DESIGN Narrative review METHODS We conducted literature searches, employing pertinent keywords, in key databases, focusing on PO-related studies/data in/for Canada since 2010, or pertinent studies/data from earlier periods not included in our previous review. In addition, we identified relevant data from "grey" literature (e.g., government, survey, other data or system reports). Relevant data were screened and extracted, and categorized into 4 main sections of indicators: 1) PO dispensing and use, 2) non-medical PO use, 3) PO-related morbidity/mortality, 4) PO-related interventions and impacts. RESULTS PO-dispensing in Canada overall continued to increase and/or remain at high levels in Canada from 2010 to 2013, with the exception of the province of Ontario where marked declines occurred starting in2012; quantitative and qualitative PO dispensing patterns continued to vary considerably between provinces. Several studies identified common "high PO dosing" prescribing practices in different settings. Various data suggested declining NMPOU levels throughout most general (e.g., adult, students), yet not in special risk (e.g., street drug users, First Nations) populations. While treatment demand in Ontario plateaued, rising PO-related driving risks as well as neo-natal morbidity were identified by different studies. PO-related mortality was measured to increase--in total numbers and proportionally--in various Canadian jurisdictions. Select reductions in general PO and/or high-dose PO dispensing were observed following key interventions (e.g., Oxycodone delisting, prescription monitoring program [PMP] introduction in Ontario/British Columbia). While physician education intervention studied indicated mixed outcomes, media reporting was found to be associated with PO prescribing patterns. LIMITATIONS The present review did not utilize systematic review standards or meta-analytic techniques given the large heterogeneity of data and outcomes reviewed. CONCLUSIONS Recently emerging data help to better characterize PO-related use, harm and intervention indicators in Canada's general context of comparatively high-level PO dispensing and harms, yet major gaps in monitoring and information persist; this continues to be a problematic challenge, especially given the implementation of key PO-related interventions post-2010, the impact of which needs to be properly measured and understood.