Prevalence of prescribed opioid claims among persons with non-traumatic spinal cord dysfunction in Ontario, Canada: a population-based retrospective cohort study

Study DesignCohort study.ObjectivesTo determine the prevalence and to identify predictors of prescription opioid use among persons with non-traumatic spinal cord dysfunction within one year after discharge from inpatient rehabilitation.SettingOntario, Canada.MethodsWe conducted a retrospective cohort study using administrative data to determine predictors of receiving prescription opioids during the one year after discharge from inpatient rehabilitation among persons with non-traumatic spinal cord dysfunction between April 1, 2004 and March 31, 2015. We modelled the outcome using a Poisson multivariable regression and reported relative risks with 95% confidence intervals.ResultsWe identified 3468 individuals with non-traumatic spinal cord dysfunction (50.35% male) with 66.58% who were aged ≥66. Over half of the cohort (59.46%) received opioids during the observation period. Being female, previous opioid use before rehabilitation, increasing comorbidity level, low functional status, and having a previous diagnosis of osteoarthritis were significant risk factors for receiving opioids after discharge, as shown in an adjusted multivariable analysis. Increasing length of rehabilitation stay was protective against opioid receipt after discharge. Risk of receiving opioids varied with age. Younger individuals had a significantly higher risk of future opioid use, a risk that peaked around 30–40 years of age (aRR 1.54, 95% CI 1.42–1.67 for age 40, as compared to age 80). Risk of opioid use following discharge decreased as age increased beyond 40 years, as compared to age 80.ConclusionsMany individuals with non-traumatic spinal cord dysfunction in Ontario are prescribed opioids after discharge from inpatient rehabilitation. This may be problematic due to the number of severe complications that may arise from opioid use and their use in this population warrants future research.