In this population-based study, we evaluated the changes of case-fatality rates and full-recovery rates in subarachnoid hemorrhage at three months and determined trends in these rates during the period of 1993–2009. We retrospectively reviewed 4,308 patients registered in the Nagasaki SAH Data Bank from 1993 to 2009. All neurosurgical units in Nagasaki Prefecture participate in Nagasaki SAH Data Bank. From 1993 to 2000, case fatality rates were 25.5%, 29.8%, 37.1%, and 51.2% in patients at ages 40–59, 60–69, 70–79, and ≥80 years, respectively. Whereas, from 2001 to 2009, these rates improved to 20.0%, 20.0%, 27.4%, and 39.2%, respectively. There were significant differences in all age groups. On the other hand, there were no significant changes in full-recovery rates between 1993–2000 and 2001–2009. The proportions of high grade SAH (Hunt & Hess Grade IV and V) and low grade SAH (Hunt & Hess Grade I and II) did not differ significantly in all age groups between 1993–2000 and 2001–2009. In all age groups, rates of radical treatment, especially with coil embolization, for ruptured aneurysms increased significantly in 2001–2009.
Advances in radical treatment and intensive management might reduce mortality in SAH but might not result in improvement of full-recovery rates at three months. Long term follow-up studies are required to accurately evaluated the favorable outcome of severe SAH.
