The 5-factor modified frailty index was a more useful associated factor of in-hospital complications than chronological age in patients younger than 74 years undergoing unruptured intracranial aneurysm surgery 1).

Chronic subdural hematoma (CSDH) is an uncommon but potentially serious complication of clipping unruptured intracranial aneurysms.

1)
Kuwabara M, Ikawa F, Michihata N, Sakamoto S, Okazaki T, Hosogai M, Maeda Y, Horie N, Kurisu K, Fushimi K, Yasunaga H. The 5-Factor Modified Frailty Index as a More Useful Associated Factor Than Chronological Age After Unruptured Cerebral Aneurysm Surgery: A Nationwide Registry Study. Neurosurgery. 2022 Nov 4. doi: 10.1227/neu.0000000000002203. Epub ahead of print. PMID: 36331212.