What causes brain aneurysms?

Brain aneurysms are primarily caused by weaknesses in the blood vessel walls, which can result from genetic factors, high blood pressure, and atherosclerosis. Other risk factors include smoking, heavy alcohol consumption, and certain medical conditions, such as connective tissue disorders. Trauma or infections can also contribute to the formation of aneurysms. While the exact cause may vary among individuals, these factors collectively increase the likelihood of developing an aneurysm.