Adherence to Oral Migraine Preventive Medications Among Patients with Chronic Migraine: Analysis of a Large US Health Insurance Claims Database (S41.009)
Adherence to Oral Migraine Preventive Medications Among Patients with Chronic Migraine: Analysis of a Large US Health Insurance Claims Database (I8-1.006)
Background Migraine prevention guidelines recommend oral prophylactic medications for patients with frequent headache. This study examined oral migraine preventive medication (OMPM) treatment patterns by evaluating medication persistence, switching, and re-initiation in patients with chronic migraine (CM). Methods A retrospective US claims analysis (Truven Health MarketScan® Databases) evaluated patients ≥18 years old diagnosed with CM who had initiated an OMPM between 1 January, 2008 and 30 September, 2012. Treatment persistence was measured at six and 12 months’ follow-up. Time-to-discontinuation was assessed for each OMPM and compared using Cox regression models. Among those who discontinued, the proportion that switched OMPMs within 60 days or re-initiated treatment between 61 to 365 days, and their associated persistence rates, were also assessed. Results A total of 8707 patients met the inclusion/exclusion criteria. Persistence to the initial OMPM was 25% at six months and 14% at 12 months. Based on Kaplan-Meier curves, a sharp decline of patients discontinuing was observed by 30 days, and approximately half discontinued by 60 days. Similar trends in time-to-discontinuation were seen following the second or third OMPM. Amitriptyline, gabapentin, and nortriptyline had significantly higher likelihood of non-persistence compared with topiramate. Among patients who discontinued, 23% switched to another prophylactic and 41% re-initiated therapy within one year. Among patients who switched, persistence was between 10 to 13% and among re-initiated patients, persistence was between 4 to 8% at 12 months. Conclusions Persistence to OMPMs is poor at six months and declines further by 12 months. Switching between OMPMs is common, but results indicate that persistence worsens as patients cycle through various OMPMs.
Comparative effectiveness of onabotulinumtoxinA versus oral migraine prophylactic medications on headache-related resource utilization in the management of chronic migraine: Retrospective analysis of a US-based insurance claims database
Background Migraine, especially chronic migraine (CM), causes substantial disability; however, health care utilization has not been well characterized among patients receiving different migraine prophylactic treatments. Methods Using a large, US-based, health care claims database, headache-related health care utilization was evaluated among adults with CM treated with onabotulinumtoxinA or oral migraine prophylactic medications (OMPMs). Headache-related health care utilization was assessed at six, nine, and 12 months pre- and post-treatment. The primary endpoint was the difference between pre- and post-index headache-related health care utilization. A logistic regression model was created to test the difference between onabotulinumtoxinA and OMPM-treated groups for headache-related emergency department (ED) visits and hospitalizations. Results Baseline characteristics were comparable between groups. The proportion of patients with ED visits or hospitalizations for a headache-related event decreased after starting onabotulinumtoxinA, but increased after starting an OMPM, for all three cohorts. Regression analyses showed that the odds of having a headache-related ED visit were 21%, 20%, and 19% lower and hospitalization were 47%, 48%, and 56% lower for the onabotulinumtoxinA group compared to the OMPM group for the six-month, nine-month, and 12-month post-index periods, respectively. Conclusions When compared with similar patients who initiated treatment with OMPM, onabotulinumtoxinA was associated with a significantly lower likelihood of headache-related ED visits and hospitalizations.
Adherence to oral migraine-preventive medications among patients with chronic migraine
Background Chronic migraine (CM) is a disabling disorder characterized by ≥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. The aim of this study was to assess adherence to 14 commonly prescribed oral migraine-preventive medications (OMPMs) among patients with CM. Methods Retrospective claims analysis of a US claim database (Truven MarketScan® Databases) was queried to identify patients who were at least 18 years old, diagnosed with CM, and initiated an OMPM (antidepressants, beta blockers, or anticonvulsants) between January 1, 2008 and September 30, 2012. Medication possession ratios (MPR) and proportion of days covered (PDC) were calculated for each patient. A cutoff of ≥80% was used to classify adherence. The odds of adherence between OMPMs were compared using logistic regression models. Results Of the 75,870 patients identified with CM, 8688 met the inclusion/exclusion criteria. Adherence ranged between 26% to 29% at six months and 17% to 20% at 12 months depending on the calculation used to classify adherence (PDC and MPR, respectively). Adherence among the 14 OMPMs was similar except for amitriptyline, nortriptyline, gabapentin, and divalproex, which had significantly lower odds of adherence when compared to topiramate. Conclusion Adherence to OMPMs is low among the US CM population at six months and worsens by 12 months.