Prevalence of Prescribed Opioid Claims Among Persons With Traumatic Spinal Cord Injury in Ontario, Canada: A Population-Based Retrospective Cohort Study

Abstract

ObjectivesTo examine prescription opioid claims among individuals with traumatic spinal cord injury (SCI) and to identify factors associated with both chronic opioid and chronic high-dose opioid use. DesignRetrospective cohort study using population-level administrative data. SettingOntario, Canada. ParticipantsIndividuals (N=1842) with traumatic SCI between April 1, 2004 and March 31, 2015. InterventionsNot applicable. Main Outcome MeasuresProportion of cohort with chronic opioid use (≥90d supply) and proportion with chronic high-dose opioid use (≥90d supply exceeding 90 mg morphine equivalent) between April 1, 2016 and March 31, 2017 (observation period). ResultsA total of 1842 individuals with traumatic SCI were identified (74% men), with a median age of 51 years (interquartile range [IQR], 34-64y) and median duration of injury of 6 years (IQR, 4-9y). During the observation period, 35% were dispensed at least 1 opioid and 19.8% received chronic opioids, 39% of whom received more than 90 mg daily (chronic high dose). The median daily morphine equivalent dose was 212 mg morphine equivalent (IQR, 135.5-345.3 mg) for chronic high-dose users. Significant risk factors for chronic opioid use were male sex; age between 40 and 60 years; lower income; multimorbidity; thoracic, lumbar, or sacral level of injury; and having a previous diagnosis of osteoarthritis. Risk factors for chronic high-dose opioid use were an extended time since injury, age between 40 and 50 years, and increasing comorbidity. ConclusionsA large proportion of individuals with traumatic SCI were dispensed an opioid in a recent 1-year period. A substantial proportion were dispensed more than 90 mg of morphine equivalents, which is the maximum recommended by the Canadian opioid guideline. Further research is needed to understand the risk factors associated with chronic, high-dose opioid use in this population.