Background and Purpose: Aneurysmal rebleeding prior to treatment is a major cause of death and morbidity in aneurysmal subarachnoid hemorrhage (SAH). Recognizing risk factors for aneurysmal rebleeding is particularly relevant and might help to identify the aneurysms that benefit from acute treatment. The aim of this study was to determine predictors for an aneurysmal rebleeding in pre-, intra- and postoperative period.
Methods: The incidence of rebleeding, demographic data, and clinical data from 5001 patients with aneurysmal SAH were retrospectively collected from Nagasaki SAH registry since January 2000 to December 2013. All clinical variables were examined by univariate analysis, and a binary logistic regression analysis was performed to identify the risk factors related to rebleeding.
Results: Rebleeding occurred in 10.3±0.5% of the 5001 aneurysm patients during the in-hospital stay (within 28 days), and the rebleeding rate was fairly constant over time. In the preoperative period, there was no difference in age, sex, aneurysm location and aneurysm number between rebleeding and non-rebleeding patients. However, Aneurysm size (P<0.01) and smoking (P<0.01) were significantly affected to the rebleeding. On the other hand, only aneurysm location (anterior communicating artery) was significantly affected to the intraoperative rebleeding (33.6% vs. 9%, P<0.01). Postoperative rebleeding rate was significantly lower in aneurysmal clipping compared with endovascular coiling, but was almost the same in the recent 5 years.
Conclusions: Aneurysmal rebleeding after SAH has a characteristics in the pre-, intra-, and postoperative period. Aneurysmal size and smoking history could be a risk factor in the preoperative period, and aneurysmal location could be a risk factor in the intraoperative period. There was no difference in the postoperative rebleeding between clipping and coiling possibly due to the development of endovascular treatment.