[Effectiveness of topiramate in migraine prophylaxis, an observational study in a consecutive case-serie].

Introduction: Open-label studies and three large and controlled trials had demostrated the efficacy of topiramate in migraine prophylaxis.
Objectives: The objective of this study was to assess the effectiveness and tolerability of topiramate in patients not previously treated with any prophylactic drug.
Patients and Methods: Patients selection was made on sequential patients attending our outpatient clinic. Patients were adults diagnosed of either transformed migraine or migraine with a frequency of more than four migraine attacks per month. Topiramate was started at 25 mg and titrated in 4 weeks by weekly increments of 25 mg, up to 100 mg/day. Patients were then followed up for a 12-week maintenance phase. Efficacy was assessed by change in mean monthly migraine attack frequency from baseline. Additional assessments included responder rates, mean number of migraine days and global impression by a seven-point improvement scale.
Results: Mean monthly migraine attacks decreased significantly from baseline (from 5.2 +/- 2.6 to 2.1 +/- 2.2; p < 0.0001). Sixty-nine percent of patients were considered responders and mean reduction rate in migraine was 55.6 %. Topiramare was overall well tolerated. Twentyfive (28.4 %) patients stopped treatment due to adverse events. The most common adverse events were paresthesia, weight loss and cognitive effects. Some grade of satisfaction was reported by 55 % of patients at the end of the study.
Conclusion: This naturalistic study confirms clinical trial data that 100 mg/day is an effective target dose for patients with migraine and presents the possible beneficial effect in transformed migraine.