Brain aneurysms develop silently. Some people may have inherited a tendency for weak blood vessels, which may lead to the development of aneurysms. Aneurysms in children are rare, and most aneurysms probably develop as a result of wear and tear on the arteries throughout a person’s lifetime. Occasionally, severe head trauma or infection may lead to the development of an aneurysm. 

There are a number of risk factors that contribute to the formation of aneurysms, listed below. Two of the most significant are, fortunately, ones that can be controlled: cigarette smoking and high blood pressure (hypertension). 

• Smoking 
• High blood pressure (hypertension) 
• Strong family history of brain aneurysms (familial aneurysms) 
• Age (over 40) 
• Gender: women have an increased risk of aneurysms 
• Race: people of color have an increased risk of ruptured aneurysms 
• Other disorders: Ehlers-Danlos syndrome, autosomal dominant polycystic kidney disease, Marfan syndrome, and fibromuscular dysplasia 
• Presence of an arteriovenous malformation (AVM) 
• Congenital abnormality in the artery wall 
• Drug use, particularly cocaine 
• Excessive alcohol use 
• Infection 
• Severe head trauma