Background: In metropolitan areas, the ratio of elderly people has been increasing. However, in rural areas it has reached a peak. We analyzed the changes in clinical features and outcomes of subarachnoid hemorrhage (SAH) and discussed the treatment strategy.

Methods: We selected consecutive SAH cases from 2001 to 2005 (Early period, 178 cases) and 2012 to 2016 (Late period, 233 cases). In the Late period, catheter intervention, cilostazol application, and early ambulation were performed. Statistical analyses involving age, Hunt-Kosnik (HK) grade, treatment methods, symptomatic vasospasm, rescue therapy, and treatment outcome were performed.

Results: The median age for both periods was 63 years; however, the ratio of patients over 75 years increased from 17% in the former to 21% in the latter. HK grades 1-3 comprised 81% of cases in both periods. Ratio of clipping/coiling/conservative treatment changed from 79/7.3/14 to 68/17/15, and coiling cases significantly increased (p＜0.05). Post-operative symptomatic vasospasm significantly decreased from 17% to 9%, and balloon angioplasty significantly increased (p＜0.05). Favorable outcome at 30 days did not change significantly (75% vs. 73%).

Conclusions: The ratio of elderly patients increased; however, the SAH outcome was not aggravated by improvement in symptomatic vasospasm treatment and less invasive treatment. Therefore, appropriate arrangement of treatment strategy keeps the SAH outcome favorable in advanced aging society.