Non-Migraine Headache Across the Menstrual Cycle in Women With and Without Premenstrual Syndrome
Fluctuation of estrogen levels across the menstrual cycle influences migraine headache. In this study, 53 women documented prospectively the incidence and severity of headache daily for an average of three menstrual cycles. Seven of the women met the criteria established by the International Headache Society for migraine with or without aura, while the remaining 46 women failed to do so. Chi-square analysis revealed that, overall, the incidence of non-migraine headache was dependent on day of the cycle (χ2 [1,66] = 247.7, p < 0.001), with more headaches occurring during the perimenstrual phase. The 46 women without migraine were further classified according to NIMH criteria into PMS ( N= 26) and non-PMS groups (n = 26). An association between headache and menstrual cycle phase was noted for both groups ( p < 0.001), although the incidence of severe headache was greater for the PMS women, during both the perimenstrual and intermenstrual phases. Both groups experienced an increase in severe headaches during the perimenstrual phase. The PMS women peaked on the day prior to menstruation, while the non PMS women peaked on the first day of menstruation. There did not appear to be an overall difference in the reporting of mild headache across the cycle between women with or without PMS. These findings suggest that (a) severe headache which does not meet the criteria for migraine with or without aura also may be menstrually related in women with and without PMS and; (b) the as yet unidentified physiological mechanism predisposing some women to PMS may also render them susceptible to more frequent, severe, non-migraine headaches both during the perimenstrual phase and throughout the entire menstrual cycle.