Topiramate vs divalproex sodium in the preventive treatment of migraine: a prospective "real-world" study

Abstract

Background and objectives: Certain neuromodulators, most notably topiramate (TPM) and divalproex sodium (DVP), are effective preventive agents for migraine. Published data from head-to-head studies comparing TPM and DVP are not available. The purpose of this study was to compare TPM and DVP for the prophyaxis of migraine in a "real-world" setting.

Methods: At 2 centers and over a period of 12 months we prospectively evaluated and treated a consecutive series of migraine patients. At baseline all were experiencing less than 15 headache days/month, and we treated all patients requiring prophylactic therapy with either TPM or DVP. We evaluated adherence, headache frequency (HF) and tolerability after 3 months of treatment. TPM treatment was initiated at 25 mg daily and increased every 10 days (25 mg) to a target of 150 mg/day (2 divided doses/day). Treatment with DVP was initiated at 250 mg daily and sequentially titrated up to 500 mg twice daily. All patients were naïve to the use of TPM and DVP.

Results: One hundred and twenty patients (104 women and 16 men of ages 18 to 68, mean 41.2 years) were included. Topiramate selectively was prescribed to 69 patients and DVP selectively to 51. Baseline HF for both groups was similar (8 ± 4 headache days/month). By intention to treat analysis at 3 months, 40 (58%) of patients initially treated with TPM and 26 (51%) of those initially treated with DVP experienced a reduction in HF of >50% (P = NS). Ten patients (14.5%) initially treated with TPM and 8 (15.7%) initially treated with DVP did not return for follow up or were begun on alternative prophylactic therapy. The most common side effects manifested by TPM patients were weight loss (50% of those who completed the treatment period), paresthesia (48%), and cognitive disturbances (20%), whereas DVP patients who completed the treatment period reported weight gain, hair loss, and gastrointestinal symptoms (approximately 24% for each). The mean doses achieved by those completing the study were 140 mg/day for TPM and 890 mg/day for DVP.

Conclusions: Although any conclusions from this investigation necessarily are limited because of our study's open-label nonrandomized design, these results suggest that TPM and DVP are reasonably effective and generally well tolerated when used to treat a "real-world" population of episodic migraineurs who require prophylaxis.