Perimenstrual migraines and their response to preventive therapy with topiramate.

INTRODUCTION: Preventive treatment with topiramate is effective for overall reduction of migraine frequency, but there are few data regarding its efficacy on perimenstrual migraines. To determine whether topiramate can prevent perimenstrual migraines, we analyzed data from premenopausal women as a subgroup of the Prolonged Migraine Prevention with Topiramate (PROMPT) study. METHODS: In total, 198 women from the PROMPT study with menstrually related migraine (MRM) were evaluated. After a one-to-two-month prospective baseline period, patients received open-label topiramate (50-200 mg/day) for six months. RESULTS: During topiramate treatment, mean monthly migraine frequency was reduced from 7.03 at baseline to 4.36 (mean change: -2.66; p < .001, endpoint analysis). Mean percentage reductions were similar for migraines during and outside the perimenstrual period (-45.9% and -46.1%, respectively). In patients with aura, reductions in migraine days with (-48.3%) or without (-43.4%) aura were similar to those in patients without aura (-45.4%). Reductions were also similar whether women were taking combined oral contraceptives (-47.0%) or were not (-46.6%). CONCLUSIONS: Topiramate reduces the frequency, but not severity or duration, of perimenstrual migraines in women with MRM, including migraines with and without aura, and regardless of combined oral contraceptive use.

Factors predicting the probability of relapse after discontinuation of migraine preventive treatment with topiramate.

INTRODUCTION: Demographic and clinical variables were examined in a post hoc analysis of the PROlonged Migraine Prevention with Topiramate (PROMPT) study to determine potential contribution to relapse. METHODS: After a six-month open-label (OL) topiramate phase, patients were randomised to continue topiramate or switch to placebo in a six-month double-blind (DB) phase. 'Relapse' was investigated in terms of change in monthly migraine days after randomisation compared with the month before randomisation, and was analysed during the first ('initial relapse') and last month ('sustained relapse') of the DB phase. More than 40 potential predicting factors were entered into analyses of variance and covariance. RESULTS: For initial relapse, variable-by-treatment interactions were significant for the Headache Impact Test (HIT-6) at DB baseline, and decline in acute medication intake or reporting of 'anxiety' in the OL phase. For sustained relapse, no statistically significant interactions were observed. CONCLUSION: Relapse after topiramate discontinuation in migraine prophylaxis appears to be unaffected by patient characteristics or baseline migraine frequency.

Topiramate in patients with episodic migraine: reducing the risk for chronic forms of headache.

OBJECTIVE: The aim was to evaluate whether preventive treatment with topiramate in patients with episodic migraine reduces the risk of developing chronic forms of headache. BACKGROUND: Chronic forms of headache, including chronic migraine or medication overuse headache (MOH), are characterized by 15 or more headache days per month. Acute medication overuse has been shown to be a risk factor for developing chronic headache, but it is not known whether preventive treatment can reduce the risk of developing chronic forms of headache or the development of MOH. METHODS: Pooled data from 3 trials in patients with episodic migraine randomized either to treatment with 100 mg topiramate per day (n = 384) or with placebo (n = 372) were analyzed with regard to the number of headache days during a prospective 4-week baseline period and the individual final 4 weeks of each patient's treatment during the planned 26-week double-blind treatment period. RESULTS: The number of headache days per month in the topiramate versus the placebo-treated groups was 7.3 +/- 3.0 versus 7.3 +/- 3.1 during baseline and 4.1 +/- 4.2 versus 5.6 +/- 4.9 during the final 4 weeks, respectively (P < .001). At the end of the study, 8 versus 16 patients fulfilled International Headache Society criteria of chronic headache (odds ratio: 2.11, P= .082). Moreover, a significantly lower number of patients receiving topiramate treatment reported an increase in headache days per month by the end of the study when compared to placebo (66 vs 88 patients, respectively; odds ratio: 1.49, P < .05). Finally, the number of days with usage of acute medication was significantly lower in the topiramate arm compared with placebo (3.3 +/- 3.7 vs 4.3 +/- 3.6, respectively; P < .001). CONCLUSION: Preventive treatment with topiramate in patients with episodic migraine may reduce the risk of developing chronic forms of headache.

Long-term migraine prevention with topiramate: open-label extension of pivotal trials.

OBJECTIVE: To demonstrate that topiramate is an effective and generally well-tolerated migraine preventive therapy when used for up to 14 months. BACKGROUND: Topiramate 100 and 200 mg/d significantly reduced mean monthly migraine frequency during 2 large, 26-week, randomized, placebo-controlled trials. Only a small number of clinical trials have examined the long-term (> or =1 year) effectiveness and safety of migraine preventive therapies. METHODS: Five hundred sixty-seven patients with an established history of migraine with or without aura were enrolled in this 8-month, open-label extension of 2 large (49 US and 52 US and Canadian medical centers), randomized, double-blind, placebo-controlled, parallel group, 26-week trials of identical design. To be eligible for the open-label extension, patients were required to have either completed the double-blind phase of the 2 pivotal migraine prevention trials or withdrew after 4 weeks due to lack of efficacy. All eligible patients, regardless of type or dose of study medication (topiramate or placebo) received in the double-blind phase, were titrated to a clinically effective dose of open-label topiramate based on physician judgment of patient response. Efficacy of topiramate was measured as the change in mean monthly migraine frequency. RESULTS: The mean topiramate dose during the open-label extension phase was 124.7 mg/d and 150.3 mg/d for patients on placebo (n = 159) or topiramate (n = 408), respectively, during the double-blind phase (N = 567, 91% female, mean age 39.4 years). Patients on topiramate for up to 14 months had 2.2 +/- 2.4 (mean +/- SD) migraines per month after completion of the open-label extension phase (3.4 +/- 2.6 at double-blind endpoint). Patients on topiramate during the open-label extension phase only (placebo during the double-blind phase) had 3.0 +/- 2.9 migraines per month at open-label extension endpoint (4.9 +/- 3.0 migraines per month at double-blind endpoint). Discontinuation rates due to adverse events during the double-blind phase were 22.2% for patients on topiramate and 11.0% for patients on placebo. Discontinuation rates due to adverse events during the open-label extension phase were 8.6% for those patients who had already received topiramate during the double-blind phase and 20.9% for those patients who had previously received placebo. CONCLUSIONS: Patients receiving topiramate experienced a sustained reduction in migraine frequency for up to 14 months. The effectiveness and safety of topiramate was consistent with that observed during 2 26-week pivotal trials.