Prognostic Significance of Sentinel Headache Preceding Aneurysmal Subarachnoid Hemorrhage

BACKGROUND: Sentinel headache (SH) is often assumed to portend an increased risk of delayed cerebral ischemia (DCI) and aneurysm rebleeding. This study aimed to re-evaluate the associations between SH and aneurysm rebleeding, DCI, and outcome after SAH. METHODS: We retrospectively analyzed 1102 patients with spontaneous SAH and available data regarding history of SH who were enrolled in the Columbia University SAH Outcomes Project between 1996 and 2009. Patients were asked whether they had experienced any episodes of acute, sudden-onset severe headache in the 2 weeks preceding the most recent bleeding event. DCI was defined as neurologic deterioration, infarction, or both due to vasospasm. Rebleeding was defined as the appearance of new hemorrhage on computed tomography. Outcome was assessed at 3 months by telephone interview using the modified Rankin Scale. RESULTS: SH was reported in 152 (14%) of 1102 patients. There were no significant differences between patients with and without SH with regard to admission Hunt-Hess grade or modified Fisher Scale. There was also no difference with regard to the frequency of aneurysm rebleeding (10% vs. 8%, P = 0.42), DCI (18% vs, 20%, P = 0.64), moderate-or-severe angiographic vasospasm on follow-up angiography (51% vs. 56%, P = 0.43), highest recorded mean middle cerebral artery flow velocity on transcranial Doppler (134 versus 128 cm/s, P = 0.30), or the distribution of modified Rankin Scale scores at 3 months. CONCLUSIONS: A history of sentinel headache before the clinical diagnosis of SAH does not imply an increased risk of DCI or further rebleeding, and carries no prognostic significance.