April 24, 2019

Predictors of chronic opioid use in non-cancer community-dwelling patients

Query 18-04: Predictors of chronic opioid use in non-cancer community-dwelling patients.

This project is Phase 2 of Q# 16-07, focusing on appropriate opioid prescribing.  This research was funded by the Drug Safety and Effectiveness Network (DSEN) and conducted by the following investigators: Yola Moride, Cristiano S Moura, Sasha Bernatsky and the CAN-AIM team.

Issue:

  • Canada has one of the highest levels of prescription opioid consumption in the world. Well-known harms of prolonged opioid use include addiction, misuse, abuse, overdose, and death. 
  • Regulators need to know how to reduce or prevent opioid-related harms while preserving the highest standards of pain care. 
  • If we could identify factors associated with chronic opioid use, we may be able to plan strategies to prevent unnecessary chronic opioid use and/or consider interventions to mitigate opioid-related harms.

Study aim:

  • To identify factors associated with chronic prescribed opioid use in the non-cancer adult population

Study description:

  • We conducted a cohort study with population-based data from Quebec’s public prescription drug insurance plan. We studied randomly selected non-cancer patients who initiated a prescription opioid in the outpatient setting from January 2012 to December 2016.
  • Patients were followed to determine, 12 months after opioid initiation, who had become a chronic opioid user. This was defined by at least 90 consecutive days or 120 or more cumulative days of active opioid prescriptions. 
  • Multivariate logistic regression was used to assess factors potentially associated with transitioning to chronic opioid use, including the prescriber’s specialty, patient sociodemographic factors, patient co-morbidity including psychiatric disorders, characteristics of the initial opioid prescription (duration, type of drug) and potential indication for opioid including chronic pain conditions.   

Study findings:

  • Among 124,492 non-cancer patients initiating a prescription opioid, 4,172 became chronic opioid users, which translated to 3.4% of the cohort. This resembles estimates obtained in recent similar studies from the United States, Europe, and Australia
  • The mean duration of opioid use over 12 months was 242.7 days for chronic users and the mean treatment intensity was the equivalent of 41.5 mg morphine per day.
  • The majority of patients have dispensed only one opioid product during follow-up, although 10.1% of chronic users used three or more different opioids.
  • Factors independently associated with the transition to chronic use included:
    1. Initial opioid prescription by a general practitioner
    2. Prescription of multiple opioids concomitantly
    3. Initiation of hydromorphone or oxycodone (versus morphine or codeine) 
    4. Patients of older age and those living in urban areas  
  • An initial opioid supply equal or greater to 30 days and a diagnosis associated with chronic pain were the strongest predictors of chronic opioid use. 
  • Regulators may consider evaluating personalized strategies to monitor patients at risk of becoming chronic opioid users, without compromising optimization of pain care

Summary:

  • Canada has one of the highest levels of prescription opioid consumption in the world and a current critical concern is regarding how to reduce or prevent opioid-related harms, such as addiction, misuse, abuse and accidental overdose, and death.
  • This study identified factors associated with chronic prescribed opioid use in the non-cancer adult population. The ultimate intent would be to help inform practice change at the point of care.
  • We studied a population-based cohort of 124,492 non-cancer patients who initiated a prescription opioid in the outpatient setting, focusing on vulnerable populations, elderly and psychiatric patients. Patients were followed to determine, 12 months after opioid initiation, which patients had become a chronic opioid user.
  • We found that 3.4% of the cohort went on to become chronic users. This is similar to estimates in other countries.
  • In new users of a prescription opioid, the strongest predictors of transition to chronic opioid use were initial supply greater or equal to 30 days and chronic pain diagnosis.
  • Personalized strategies to monitor patients at risk of becoming chronic opioid users may be helpful, but should not compromise optimal pain care.

For more information, contact: Autumn Neville, Research Coordinator. [email protected]