Objectives: In a 12-month observational study, we evaluated the effect of opioid use on the outcomes in 1700 adult patients with fibromyalgia.
Methods: Data were evaluated using propensity score matching after patients were divided into cohorts based on their baseline medication use: (1) taking an opioid (concurrent use of tramadol was permitted); (2) taking tramadol (but no opioids); and (3) not taking opioids or tramadol. Changes in outcomes were assessed using the Brief Pain Inventory for severity and pain-related interference (BPI-S, BPI-I), Fibromyalgia Impact Questionnaire (FIQ), Patient Health Questionnaire for depression (PHQ-8), Insomnia Severity Index (ISI), Sheehan Disability Scale (SDS), 7-item Generalized Anxiety Disorder Scale (GAD-7), and economic factors. Time-to-opioid or tramadol discontinuation was analyzed using Kaplan-Meier survival analyses.
Results: Compared with the opioid cohort, the nonopioid cohort demonstrated significantly greater reductions (P<0.05) in BPI-I, FIQ, PHQ-8, SDS, and ISI; the tramadol cohort compared with the opioid group showed greater reductions on FIQ and ISI. Reductions in BPI-S and GAD-7 did not differ significantly among cohorts. Compared with the opioid cohort, patients in the tramadol cohort had fewer outpatient visits to health care providers. Few significant differences were found between the tramadol and nonopioid cohorts across outcomes.
Discussion: Although pain severity was reduced over time in all cohorts, opioid users showed less improvement in pain-related interference with daily living, functioning, depression, and insomnia. Overall, the findings show little support for the long-term use of opioid medications in patients with fibromyalgia given the poorer outcomes across multiple assessment domains associated with this cohort.
*Eli Lilly and Company
∥VA HSR&D Center of Excellence for Implementing Evidence-Based Practice, Indiana University
¶Regenstrief Institute Inc.
**PharmaNet/i3, Indianapolis, IN
†Seattle Rheumatology Associates
‡Division of Rheumatology Research, Swedish Medical Center
§Department of Internal Medicine, University of Washington School of Medicine, Seattle, WA
#Chronic Pain and Fatigue Research Center, University of Michigan, Ann Arbor, MI
††Kaiser Permanente, Escondido, CA
‡‡INC Research, Raleigh, NC
X.P., R.L.R., D.F., and M.W. are employees of and/or shareholders in Eli Lilly and Company (Indianapolis, IN). D.A.W. is a consultant for Eli Lilly and Company, Forest Pharmaceuticals, Pfizer, Jazz Pharmaceuticals, and Bristol Meyers Squibb. Y.C. is an employee of PharmaNet/i3. B.M. is an advisor for NeurogesX. P.M. receives research funding and consulting fees and is an honoraria speaker for Eli Lilly and Company, Forest Pharmaceuticals, and Pfizer. D.H. is a medical writer with INC Research. The REFLECTIONS study was sponsored by Eli Lilly and Company or one of its subsidiaries. K.K. declares no conflict of interest.
Reprints: Xiaomei Peng, MD, PhD, Eli Lilly and Company, Indianapolis, IN 46285 (e-mail: Peng_Xiaomei@Lilly.com).
Received July 26, 2013
Received in revised form February 17, 2014
Accepted January 21, 2014