Systematic review of migraine prophylaxis adherence and persistence.

BACKGROUND Migraine is a common neurological disease affecting 12% of Americans and millions worldwide. Medication adherence has been studied extensively in many chronic conditions, with poor adherence adversely affecting treatment outcomes. However, little is known about adherence to oral prophylaxis for migraine. OBJECTIVE To examine the literature on assessing oral prophylaxis medication adherence and persistence among migraine patients. METHODS A systematic search of the PubMed (1966 to present) and EMBASE (1974 to present) databases was conducted to locate prospective and retrospective observational studies and randomized controlled trials (RCTs) of propranolol, amitriptyline, and topiramate. RCTs were pooled, weighted by sample size, and stratified by drug and length of study. Average persistence rates and reasons for discontinuation cited in RCTs were examined for each medication. RESULTS A total of 788 unique articles were identified using the search criteria, 33 of which were included in the final review. Observational studies (n = 14) showed adherence ranges of 41% to 95% at 2 months, 21% to 80% at 6 months, and 35% to 56% at 12 months and persistence ranges of 41% to 88% at 2 months, 19% to 79% at 6 months, and 7% to 55% at 12 months. Pooled persistence from RCTs on propranolol, amitriptyline, and topiramate (n = 19) showed rates of 77%, 55%, and 57%, respectively, at 16-26 weeks. Adverse events were the most common reason for discontinuation cited (24% for topiramate and 17% for amitriptyline). CONCLUSION Observational studies and pooled data from RCTs demonstrate poor adherence and persistence to oral migraine prophylaxis.