Defining migraine days, based on longitudinal E-diary data

BackgroundThere is a need for standardization of the definition of a migraine day for clinical and research purposes. MethodsWe prospectively compared different definitions of a migraine day with E-diary data of n = 1494 patients with migraine. We used a baseline definition based on migraine characteristics with a duration of >= 4 hours OR triptan intake (independently from its effect) OR (visual) aura lasting 5-60 minutes. ResultsOf all migraine days defined by triptan intake only, 66.2% had a duration <4 hours. Adjusting the headache duration criterion to >= 30 minutes led to a decrease in days defined by triptan intake only and resulted in a 5.4% increase in total migraine days (equals 0.45 migraine day increase in monthly migraine days). These additional migraine days had a median duration of 2.5 hours. ConclusionWe propose to define a migraine day as follows: 1) (a) headache duration >= 30 minutes; (b) matching >= 2 of four characteristics: unilateral, pulsating, moderate to severe pain, aggravation by or causing avoidance of routine physical activity; and (c) during headache >= 1 of the following: nausea and/or vomiting, photophobia and phonophobia or 2) (visual) aura duration 5-60 minutes or 3) a day with headache for which acute migraine-specific medication is used irrespective of its effect.