Presented at the 2012 AAPM Annual Meeting « Back

Identifying Predictors of Chronic Hydrocodone Use

J. Bradford Rice, PhD, brice@analysisgroup.com¹, Thomas M. Samuelson, BA², Howard G. Birnbaum, PhD², Nathaniel Katz, MD MS³, (1) Economic Consultant, Boston, Massachusetts, (2) Analysis Group, Boston, Massachusetts, (3) Pain Management, Pharmaceuticals, Natick, Massachusetts

Introduction: Although chronic pain affects over 100 million Americans, significant unmet need remains. Hydrocodone is the most frequently prescribed pain treatment, however most formulations contain acetaminophen, a leading cause of liver failure. This study identifies key characteristics that may help prescribers assess the likelihood of chronic hydrocodone use, and further inform appropriate treatment options. Methods: Patients 18–64 years old initiating hydrocodone (2006–2009) were selected from a de-identified privately insured administrative claims database. Patients were required to have continuous eligibility and no long-acting opioid use in the 6 months prior to and 15 months following hydrocodone initiation (n = 424,810). Chronic use was defined as having any 90-day period with a minimum average daily dose of 20mg in the 15 months following hydrocodone initiation (i.e., patients can become chronic users within one year following initiation). Characteristics of chronic and non-chronic users were compared using logistic regression. Results: Approximately 5% of hydrocodone patients were chronic users; 2% of hydrocodone patients progressed to chronic use within one year of initiation. Chronic users exhibited the following characteristics prior to initiation: 1) use of other short-acting opioids; 2) diagnosis of insomnia; 3) pain diagnoses including back pain, osteoarthritis, rheumatoid arthritis, fibromyalgia, and neuropathic pain; and 4) knee replacement or spinal surgery. Conclusions: This study identifies characteristics associated with progression to chronic hydrocodone use. Evaluation of such characteristics could help physicians recognize these patients, and further inform treatment in a population susceptible to complications associated with long-term acetaminophen use. References: 1)Institute of Medicine, "Relieving pain in America: A blueprint for transforming prevention, care, education, and research," 2011 The National Academies Press, Washington DC, pp. S-1, 3-15. 2)Larson et al. "Acetaminophen-induced acute liver failure: Results of a United States multicenter, prospective study, Hepatology 2005; 42(6): 1364-1372. 3)Von Korff et al. “De facto long-term opioid therapy for noncancer pain," Clin J Pain. 2008;24:521-527.

Funding: Funding provided by Zogenix Inc.