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

Abstract

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. 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 follow-up examinations. 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. 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.