Cluster headache: severity and temporal profiles of attacks and patient activity prior to and during attacks.

A detailed clinical study of 77 spontaneous cluster headache attacks has been carried out. The information was recorded during a period when patients were without medication and with the use of methods which were not dependent on the patients' memory of events. The findings stress the usual rapid onset and termination of attacks, and their short duration. There was a preponderance of attacks beginning during sleep and the majority of daytime attacks began when patients were physically relaxed. No significant difference between nocturnal and daytime attacks was found as regards severity or temporal profiles. A significant positive correlation was found between severity of maximal pain and both duration of maximal pain and total duration of attacks. "Abortive attacks" accounted for 16% of attacks. The apparent spontaneous arrest of these attacks does not appear to be due to special features of patient activity prior to or during attacks, nor are they restricted to a refractory period following more severe attacks.