Cluster headache: on the significance of so-called minibouts.

Cluster headache periods (bouts) have, at the lower end of the scale, been supposed to last for periods as short as 1-2 weeks. Patients who usually have bouts of ordinary duration occasionally have brief attacks in the remission phase ("abortive attacks"). The group described here had a temporal pattern, clearly at variance with both these patterns: The six patients had mostly or entirely bouts of less than 1 week's duration. We have termed such short-lasting bouts minibouts, on the supposition that such cases belong within the cluster headache cycle. All the patients were men and had a history of unilateral headache without side shift, and usually the solitary attacks had some autonomic accompaniments, although of a moderate degree. In four cases only mild attacks occurred, whereas in two cases the attacks were rather severe and not consistent with full working ability. The group as such may not be homogeneous. The nosologic status of patients with bouts lasting only 1-2 days is somewhat uncertain. As long as the substrate of cluster headache is not outlined, the lower end of duration of minibouts cannot be accurately identified. The fact that three patients recently have experienced bouts of ordinary length strengthens the view that such cases really belong to the cluster headache cycle.