Common migraine as a weekly and seasonal headache.

The aim of this study was to demonstrate that a possible recurrence may pertain to migraine attacks (MAs). The study was carried out by checking the personal diaries of 30 migraine sufferers ("migraineurs") who carefully annotated the date of their MA over twelve consecutive months. The group was composed of 15 males and 15 females, ranging in age from 17 to 37 years. The individual MAs were summarized in order to obtain the time-qualified frequency per each time period of recurrence. The periodicity in time data series was analysed by means of the Single Cosinor method. The rhythmometric analysis was found to be highly statistically significant; the circaseptan (P = 0.007) and circadian (P = 0.004) recurrence of MA showing critical incidence on Sunday and in January, respectively. No circatrigintan periodicity was validated in relation to the solar and lunar months or menstrual cycle. These findings suggest to us a possible linkage of MA to environmental factors which entrain the routine of our lives. Because of the circaseptan and circannual repetitivities, common migraine syndrome was defined as a "weekly and seasonal headache".