Adherence to Oral Migraine Preventive Medications Among Patients with Chronic Migraine: Analysis of a Large US Health Insurance Claims Database (S41.009)

Abstract

OBJECTIVE: The aim of this study was to assess adherence to 14 commonly prescribed oral migraine preventive medications (OMPM) among patients with CM. BACKGROUND: Chronic migraine (CM) is a disabling disorder characterized by 蠅15 headache days per month that has been shown to significantly reduce quality of life. Migraine prevention guidelines recommend preventive medications as the standard of care for patients with frequent migraine. DESIGN/METHODS: A retrospective claims analysis was undertaken using Truven MarketScan^® Databases (2007 - 2012), which comprise US commercial, Medicare supplemental, and Medicaid claims for over 40 million unique lives per year. Patients who were at least 18 years old, were diagnosed with CM, and who initiated an OMPM between January 1, 2008 and September 30, 2012 were included in the analysis. Medication possession ratios (MPR) and proportion of days covered (PDC) were calculated for each patient and a cut-off of 蠅80% was used to classify adherence. The odds of adherence between OMPM was compared using logistic regression models. RESULTS: A total of 75,870 CM patients were identified, of which 9,614 met our inclusion criteria. A majority of the patients were middle-aged women, employed full time, resided in a metropolitan area, and had significant co-morbidities. Adherence ranged between 26% to 29% at 6 months and 17% to 20% at 12 months (using PDC and MPR respectively). Among the 14 OMPMs amitriptyline, nortriptyline, gabapentin, and divalproex had significantly lower likelihood of adherence when compared to topiramate. CONCLUSIONS: Adherence to oral migraine preventive medications is low among the US chronic migraine population at 6 months and declines even further by 12 months. Further research evaluating reasons for non-adherence, and strategies to improve adherence, is needed. Study Supported by: Allergan Inc.

Disclosure: Dr. Hepp has nothing to disclose. Dr. Dodick has received personal compensation for activities with Allergan, Inc., Pfizer Inc., Merck & Co., Inc., ENeura NuPathe, Colucid, Alder, Artaeus, Eli Lilly & Company, Amgen Inc., WL Gore, Bristol-Myers Squibb Company, Ethicon J&J, ATI, Zogenix, Cognimed, Intramed, Scientiae, Syndergy, Curatio CME, and Pfizer Inc. Dr. Dodick has received personal compensation in an editorial capacity for Sage Publishing, Lippincott, Oxford University Press, Cambridge University Press, UpToDate, and Web MD. Dr. Varon has received personal compensation for activities with Allergan Inc. Dr. Varon holds stock and/or stock options in Allergan Inc., which sponsored research in which Dr. Varon was involved as an investigator. Dr. Gillard has received personal compensation for activities with Allergan Inc. as en employee. Dr. Hansen has nothing to disclose. Dr. Devine has nothing to disclose.