Patterns of Opioid Exposure in the Emergency Care System and Prolonged Opioid Use Among Opioid-Naïve Adults With Low Back Pain

Abstract

The objectives of this thesis were to: 1) describe the characteristics of opioids delivered to opioid-naïve adults with low back pain as they transition through a Canadian emergency care system; 2) identify different patterns of opioid exposure; and 3) investigate associations of these patterns with prolonged opioid use. I conducted a retrospective cohort study using linked administrative data in Halifax, Nova Scotia, Canada. I captured opioid delivery at four key points of emergency care management: ambulance, emergency department, discharge, and community pharmacy. I used generalized estimating equations to estimate associations between patterns of opioid exposure and prolonged opioid use, defined as filling an opioid prescription 4-180 days after the index emergency department visit. Opioid-naïve adults with low back pain had varying patterns of opioid exposure in the emergency care system. Patients who received opioids at multiple points in the care process were more likely to transition to prolonged opioid use.