Is Age a Risk Factor for Poor Outcome of Surgical Treatment of Unruptured Intracranial Aneurysms?

OBJECTIVE: Advanced age is known to be a significant risk factor for the rupture of intracranial aneurysms. The impact of age on outcomes of surgically treated patients with unruptured intracranial aneurysms (UIAs) is less clear. METHODS: A total of 663 consecutive patients with 823 surgically treated UIAs were evaluated. UIAs, which need bypass surgery including low-flow or high-flow bypass, were defined as complex aneurysms. Aneurysm size was categorized as small (<15 mm), large (15-24 mm), and giant (>= 25 mm). In patients without symptoms, a poor outcome is defined as a modified Rankin Scale (mRS) score of 2-6. In those with mRS score higher than 1 as a result of UIA-related symptoms or other comorbidities, a poor outcome is defined as an increase of 1 or more on the mRS. Outcomes were evaluated at the 6-month and 12-month followup examinations. RESULTS: The mean age was 62 +/- 12 years and 650 UIAs (78%) were observed in women. Previously treated aneurysm (P = 0.009), posterior circulation aneurysm (P < 0.0001), complex aneurysm (P < 0.0001), a larger size (P = 0.011), and perforator territory infarction (P < 0.0001) were related to poor outcome at 6 months, and posterior circulation aneurysm (P < 0.0001), complex aneurysm (P < 0.0001), a larger size (P = 0.035), and perforator territory infarction (P = 0.013) were related to poor outcome at 12 months. Age was not associated with poor outcome in patients with UIAs who undertook direct surgery. CONCLUSIONS: Although risks and benefits of aneurysm treatment in older patients should be carefully considered,surgical treatment of UIAs in the elderly should be considered positively.