title: Opioid rotation in patients initiated on oxycodone or morphine: a register study.
abstract: OBJECTIVE
  Strong opioids are recommended for the treatment of moderate to severe pain. However, some patients do not achieve a successful treatment outcome due to intolerable adverse events and/or inadequate analgesia, thus may benefit from switching to another opioid, a procedure known as "opioid rotation." The type of opioid at treatment initiation may influence the risk of opioid rotation and the objective of this study was to assess such rotation after treatment initiation with two alternative treatments, controlled-release (CR) oxycodone versus CR morphine in patients suffering from non-cancer pain.
  
  
  METHODS
  The study reported here was a real-life study based on Swedish register data: the Prescribed Drug, National Patient, and Cause of Death registers. The captured data cover the entire Swedish population treated in specialist care. A statistical analysis plan was agreed and signed before data were accessed.
  
  
  RESULTS
  Data from 50,223 cases were included in the analyses. The risk of rotation was 19% higher in patients initiating treatment with morphine compared with oxycodone (hazard ratio 1.19; 95% confidence interval 1.11-1.27; P < 0.001), after adjusting for such baseline variables that were both significantly correlated with the outcome variable (time to rotation) and significantly different between the groups; age at index date, osteoarthritis and number of pain-related drugs.
  
  
  CONCLUSIONS
  Patients with non-cancer pain who initiated treatment with CR morphine had a higher risk of opioid rotation than patients initiated with CR oxycodone.
authors.affiliation: Nordic Health Economics.
authors.forename: Lisa
authors.initials: L
authors.lastname: Ericson
authors.forename: Anneli
authors.initials: A
authors.lastname: Ambring
authors.forename: Ingela
authors.initials: I
authors.lastname: Björholt
authors.forename: Peter
authors.initials: P
authors.lastname: Dahm
keywords: Sweden; drug rotation; nationwide data; non-cancer pain