Clinical characteristics of subarachnoid hemorrhage with or without headache.

Objective: Some patients report the absence of a typical headache at the onset of subarachnoid hemorrhage (SAH). We investigated the clinical backgrounds and characteristics of patients with SAH without headache and compared the findings with those of patients with SAH and headache.
Methods: We examined 224 patients retrospectively who underwent intracranial aneurysmal clipping. Patient's characteristics, Fisher's computed tomography grade, situation at onset, site of ruptured aneurysm, and symptoms were compared. Subjects were categorized into two groups: headache group and nonheadache group.
Results: Eighteen patients (8.0%) did not present with headache. There were no significant differences in terms of age, sex, Fisher's computed tomography grade, onset time, or site of ruptured aneurysm.
Conclusions: The patients without headache have no specific clinical characteristics over patients with common SAH.