Impact of Opioid Agonist Therapies (OAT) on non-fatal and fatal overdose in Ontario: patterns of OAT used among people living with OUD

Summary

Client: IQVIA Solutions Canada Inc.

Project ID: P2024-221/ 2026 0980 006 000

Research Question/Objectives: Opioid use disorder (OUD) is a chronic condition characterized by a strong desire to use opioids, increased tolerance, and withdrawal symptoms upon opioid cessation. In Canada, OUD has led to significant health and economic burdens, with over 47,000 opioid toxicity deaths from 2016 to 2024. Opioid agonist therapies (OAT), such as methadone (MET) and buprenorphine (BUP), are effective interventions that reduce hospital admissions and fatal overdoses. Canadian guidelines consider various factors for OAT, while both MET and BUP have demonstrated similar efficacy, MET has shown better retention, but higher risk of mortality during the first four weeks of treatment. Extended-release BUP (BUP-XR) may lower overdose rates and improve treatment retention. Further research is needed to optimize OAT recommendations and outcomes, and inform clinical practice to help potentially reduce mortality during the opioid crisis.”

Objectives:
The primary objective of this study is to:

1. To assess the impact of OATs on opioid-related fatal OD and opioid-related non-fatal OD among patients with OUD, by OAT use at the time of the event

The secondary objectives of this study are to:

1. Describe the patterns of OAT usage and the associated factors that may influence opioid-related fatal and non-fatal OD between the different OATs among patients with OUD
2. Describe key patient demographic and clinical characteristics of patients with OUD who have initiated OATs

The exploratory objectives of this study are to:

1. Evaluate how the contribution of illicit drug use (opioid and non-opioid) may impact opioid-related fatal and non-fatal OD among patients with OUD, by OAT use at the time of the event
2. Evaluate the impact of slow-release oral morphine (SROM), hydromorphone, and injectable diacetylmorphine on opioid-related fatal and non-fatal OD in patients with OUD

Status: In progress