A prospective comparison between ICHD-II and probability menstrual migraine diagnostic criteria.

OBJECTIVE: To prospectively evaluate the diagnosis of menstrual migraine (MM) by comparing 2 diagnostic systems.

METHODS: Female migraineurs self-reporting a substantial relationship between migraine and menses were evaluated with 3 consecutive months of daily headache recording diaries. A relationship between menses and migraine was evaluated using International Classification of Headache Disorders (ICHD-II) criteria and a probability model called Probability MM.

RESULTS: Three months of pretreatment prospective diaries were completed by 126 women. ICHD-II menstrually related migraine was diagnosed in 73.8% with pure MM in 7.1%. ICHD-II and Probability diagnoses agreed for all cases of ICHD-II non-MM and pure MM, with disagreement among women diagnosed with ICHD-II menstrually related migraine, only half of whom were identified as having a relationship with menses greater than chance alone using the Probability model. Interestingly, 20% of those women self-reporting a substantial relationship between migraine and menses were not prospectively diagnosed with MM using either diagnostic system. Differences in menstrual vs nonmenstrual headaches were greater when using the Probability model.

CONCLUSIONS: Prospective headache diaries are needed to diagnose MM. A probability-based method, which considers the chance occurrence of headaches during the menstrual cycle, identifies fewer women as having menstrually related migraine compared with the diary-based methods recommended by the current ICHD-II candidate criteria.