PS2-29 EVIDENCE SYNTHESIZE TO AID PRESCRIBING DECISIONS FOR POSTOPERATIVE PAIN MANAGEMENT

Monday, October 24, 2016
Bayshore Ballroom ABC, Lobby Level (Westin Bayshore Vancouver)
Poster Board # PS2-29

Karishma Desai, PhD., MS, B.Pharm1, Ian Carroll, M.D., MS1, Steven Asch, MD, M.P.H.2, Kathryn McDonald, MBA, B.S1, Tina Seto1, Catherine Curtin, M.D.1 and Tina Hernandez-Boussard, PhD, MPH, MS1, (1)Stanford University, Stanford, CA, (2)VA Palo Alto Health Care System, Menlo Park, CA
Purpose:

Pain management and opioid use are under great scrutiny in the US. New empirical evidence suggests that certain pain medication (Prodrug opioids) is rendered ineffective when combined with certain antidepressants (serotonin reuptake inhibitors, SSRIs).  This study leverages routinely collected medication and pain score data from Electronic Health Records (EHRs) to generate evidence on the effect of the prescribed combination of SSRIs and Prodrugs – information useful for clinical decisions based on drug-drug interactions. 

Method:

This retrospective study used EHRs from a single academic medical center. We identified patients undergoing four surgical procedures (distal radial fracture, mastectomy, thoracotomy & total knee replacement) using ICD-9-CM/ICD-10-CM. We extracted standardized pain scores from the medical record, and using administration time stamps identified patients administered SSRI’s and a Prodrug during their inpatient stay. We assessed the prevalence of concomitant use of these medications during the in-patient stay and at follow-up. Maximum pain score at discharge and maximum follow-up pain score (within 30-days) were dependent variables used in separate multivariate regression analyses to examine the effect of the combined use of SSRIs and Prodrugs on post-operative pain. Patient characteristics were controlled for in the models.

Result:

Our cohort included 12,771 patients who underwent surgery of which 6,946 had follow-up a visit pain score. Overall, 4% had documented SSRIs use during their hospital stay and 93% received both an SSRI and opioid Prodrug post-surgery. The patients receiving the combined medications were associated with higher discharge pain scores (Odds Ratio [OR]: 1.95, 95% Confidence Interval [CI]: 1.52, 2.45) and higher follow-up pain scores (OR: 2.56, CI: 1.73, 3.74) compared to non-antidepressant patients after controlling for important demographic characteristics. 

Conclusion:

Evidence from this large study support the need for clinical decision support tools to aid physicians prescribing opioids for postoperative pain management. Our results demonstrate that patients on SSRIs and opioid Prodrugs have poorer pain management compared to other patients. In practical terms, this co-prescribing pattern could affect a patients’ ability to manage their postoperative pain, potentially leading them to request additional and continued opioid prescriptions. This study adds to evidence of consequential drug interactions, while the high prevalence of concomitant use suggests that more attention to medication prescribing choices is warranted for post-operative pain management.