Relationship between Aging and Enlargement of Intracranial Aneurysms

To predict possible enlargement of cerebral aneurysms with aging, we retrospectively analyzed aneurysm size in relation to patient age and aneurysm site.

We included 1332 unruptured and 2362 ruptured aneurysms detected in patients from the Yamaguchi Prefecture, Japan, from 1995 to 2005.

Age-specific site distribution was not found in the unruptured aneurysms. In the ruptured aneurysms, the incidence of anterior communicating artery (AComA) aneurysms was higher than that of internal carotid posterior communicating (ICPC) artery aneurysms among the patients aged 40-49 years (32.6% versus 14.4%), whereas the difference was small among the elderly patients aged 70-79 years (25.8% versus 24.9%). In the AComA aneurysms, either in the unruptured or ruptured cases, no age-related change in size was found. In the ICPC aneurysms, either in the unruptured or in the ruptured cases, the size of the aneurysms 7 mm or larger increased with age.

The sizes of AComA aneurysms may remain stable with aging. Therefore, the risk of rupture may be similar in young and elderly patients. Meanwhile, ICPC artery aneurysms may continue to grow throughout the patient's life, with an increasing risk of rupture.