Analysis of the duration of migraine prophylaxis

To determine the minimum duration of migraine prophylaxis, after patients become pain-free. Migraine patients diagnosed according to criteria of International Classification of Headache Disorders-2 were treated prophylactically. After becoming pain-free, they were divided into two equal groups: in group 1, prophylaxis was maintained for another 12 months and in group 2, for 24 months. Each group was followed for more three years after prophylaxis period. Of the 50 patients, 39 (78%) were female and 11 (22%) were male. The age ranged from 18 to 50 years. Before treatment, the attack frequency for groups 1 and 2 was, respectively, 16.3 ± 12.8 and 16.4 ± 11.8 days per month (p = 0.769). Patients in groups 1 and 2 have become pain-free, respectively, with 21.4 ± 11.2 and 16.8 ± 9.9 months (p = 0.161). During three years without treatment, groups 1 and 2 maintained an annual frequency of respectively 3.2 and 0.5 headache days. Of the patients in group 2, 76.0% (19/25) remained pain-free during follow-up, versus 44.0% (11/25) of group 1, with a significant difference (p = 0.001). The best results were obtained when migraine prophylaxis was maintained for 24 months after patients became pain-free.