Autopsy studies indicate that cerebral aneurysms are fairly common in adults, with a prevalence ranging between 1% and 5%.[2]Wiebers DO, Whisnant JP, Huston J 3rd, et al. Unruptured intracranial aneurysms: natural history, clinical outcome, and risks of surgical and endovascular treatment. Lancet. 2003;362:103-110.
http://www.ncbi.nlm.nih.gov/pubmed/12867109?tool=bestpractice.com
[3]Korja M, Kaprio J. Controversies in epidemiology of intracranial aneurysms and SAH. Nat Rev Neurol. 2016 Jan;12(1):50-5.
http://www.ncbi.nlm.nih.gov/pubmed/26670298?tool=bestpractice.com
Prevalence of intracranial aneurysms among adults is estimated between 1.0% and 3.2%.[4]Atkinson JL, Sundt TM Jr, Houser OW, et al. Angiographic frequency of anterior circulation intracranial aneurysms. J Neurosurg. 1989 Apr;70(4):551-5.
http://www.ncbi.nlm.nih.gov/pubmed/2926495?tool=bestpractice.com
[5]Vlak MH, Algra A, Brandenburg R, et al. Prevalence of unruptured intracranial aneurysms, with emphasis on sex, age, comorbidity, country, and time period: a systematic review and meta-analysis. Lancet Neurol. 2011 Jul;10(7):626-36.
http://www.ncbi.nlm.nih.gov/pubmed/21641282?tool=bestpractice.com
Therefore, 3 to 12 million Americans harbor intracranial aneurysms. The incidence of reported ruptured aneurysms is about 6 to 7 in every 100,000 people per year.[6]Asaithambi G, Adil MM, Chaudhry SA, et al. Incidences of unruptured intracranial aneurysms and subarachnoid hemorrhage: results of a statewide study. J Vasc Interv Neurol. 2014 Sep;7(3):14-7.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4188252
http://www.ncbi.nlm.nih.gov/pubmed/25298853?tool=bestpractice.com
Cerebral aneurysms can occur at any age but are more common in adults than children. Women are approximately 1.6 times more likely to harbor cerebral aneurysms than men.[5]Vlak MH, Algra A, Brandenburg R, et al. Prevalence of unruptured intracranial aneurysms, with emphasis on sex, age, comorbidity, country, and time period: a systematic review and meta-analysis. Lancet Neurol. 2011 Jul;10(7):626-36.
http://www.ncbi.nlm.nih.gov/pubmed/21641282?tool=bestpractice.com
Epidemiologic studies show that 7% to 20% of patients with aneurysmal subarachnoid hemorrhage have a first- or second-degree relative with a confirmed intracranial aneurysm.[7]Norrgard O, Angquist KA, Fodstad H, et al. Intracranial aneurysms and heredity. Neurosurgery. 1987 Feb;20(2):236-9.
http://www.ncbi.nlm.nih.gov/pubmed/3561729?tool=bestpractice.com