title: Pressure sensitivity and phenotypic changes in patients with suspected opioid-induced hyperalgesia being withdrawn from full mu agonists.
abstract: OBJECTIVE
  To assess changes in phenotype and pressure sensitivity in patients with suspected opioid-induced-hyperalgesia (OIH) after transitioning to buprenorphine.
  
  
  METHODS
  Twenty patients with suspected OIH were enrolled to transition to buprenorphine therapy. Patients completed validated self-report measures at baseline and at 1, 4, 8 weeks, and 6 months after initiation of buprenorphine along with quantitative sensory testing including measures of pressure pain threshold, pain tolerance and Pain 50 (a pain intensity rating).
  
  
  RESULTS
  20 patients were enrolled, 17 were treated with buprenorphine and 11 completed all assessment points. We found that after transitioning to buprenorphine, patients on higher opioid doses (≥100mg oral morphine equivalents) had significant improvements for some measures including decreased pain severity and fibromyalgia survey scores, fewer neuropathic pain features, less catastrophizing, fewer depressive symptoms, and improved functioning 1-week after transitioning to buprenorphine with an eventual return back to baseline. Although not statistically significant, patients on high dose opioids (≥100mg OME) also showed a trend of decreased pressure sensitivity 1-week after transitioning to buprenorphine with a gradual return back to baseline.
  
  
  CONCLUSIONS
  Our study is the first to look at pressure pain sensitivity in patients who were taking opioids and transitioned to buprenorphine. These results suggest that the patients most likely to benefit from buprenorphine therapy are those on higher doses. In addition, the eventual return back to baseline on measures of pain phenotype and pressure sensitivity suggests that buprenorphine may over time result in a return of the hyperalgesic effects of a full mu agonist.
authors.affiliation: Department of Anesthesiology, University of Michigan Health System, Ann Arbor, MI, USA.
authors.forename: Ronald A
authors.initials: RA
authors.lastname: Wasserman
authors.affiliation: Department of Anesthesiology, University of Michigan Health System, Ann Arbor, MI, USA.
authors.forename: Afton L
authors.initials: AL
authors.lastname: Hassett
authors.affiliation: Department of Anesthesiology, University of Michigan Health System, Ann Arbor, MI, USA.
authors.forename: Steven E
authors.initials: SE
authors.lastname: Harte
authors.affiliation: Department of Anesthesiology, University of Michigan Health System, Ann Arbor, MI, USA.
authors.forename: Jenna
authors.initials: J
authors.lastname: Goesling
authors.affiliation: Department of Anesthesiology, University of Michigan Health System, Ann Arbor, MI, USA.
authors.forename: Herbert L
authors.initials: HL
authors.lastname: Malinoff
authors.affiliation: Department of Anesthesiology, University of Michigan Health System, Ann Arbor, MI, USA.
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Berland
authors.affiliation: Department of Anesthesiology, University of Michigan Health System, Ann Arbor, MI, USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Zollars
authors.affiliation: Department of Anesthesiology, University of Michigan Health System, Ann Arbor, MI, USA.
authors.forename: Stephanie E
authors.initials: SE
authors.lastname: Moser
authors.affiliation: Department of Anesthesiology, University of Michigan Health System, Ann Arbor, MI, USA.
authors.forename: Chad M
authors.initials: CM
authors.lastname: Brummett
keywords: Buprenorphine; Mu Agonists Withdrawal; Opioid-Induced Hyperalgesia; Phenotypic Changes; Pressure Sensitivity