Aneurysm refers to the abnormal widening of an artery due to weakness in the wall of the blood vessel. MedlinePlus notes that aneurysms can occur in different locations of the body such as the aorta, brain and intestines. Aneurysms within the body or near the brain often have no symptoms. Ruptures occur leading to low blood pressure or lightheadedness; however, in many cases significant damage occurs such as internal bleeding, stroke or death prior to knowing the aneurysm exists. The exact cause of aneurysm is not fully understood.
Atherosclerosis
Atherosclerosis occurs when plaque builds up inside the artery walls that carry oxygen-rich blood to the heart and other organs. The National Heart Lung and Blood Institute indicates that certain conditions increase the risk of developing atherosclerosis such as sedentary lifestyle, unhealthy diet and aging. Plaque is made up of fatty deposits, cholesterol and calcium. Accumulation of plaque in the arteries weakens the walls of the aorta, increasing the pressure of blood forced through the arteries as well as creating blockage. The aneurysm can grow in this case and rupture, or burst.
Smoking and Alcohol
A 2007 study in the "American Journal of Epidemiology" concluded that use of alcohol and smoking have a significant impact on the development of aortic aneurysms. The study notes that aortic aneurysms are the 10th leading cause of death in men over the age of 55 years old in the United States. The findings from this study explain that both smoking and alcohol use increase the risk of chronic high blood pressure, which is a factor in causing arterial blockage leading to aneurysm. Additionally, the study notes that chronic smoking and alcohol use worsens symptoms of other medical conditions such as diabetes and high cholesterol, further contributing to the risk of developing aneurysms.
Traumatic Injury
Brain aneurysms form as an abnormal bulge in the brain artery, which may leak blood into space around the brain, causing cell damage. The Cleveland Clinic explains that severe traumatic head injury, in the form of car accidents or hits to the head, is one potential cause of this type of aneurysm. Thoracic aortic aneurysms, in the upper chest area, are also caused by traumatic injury. MayoClinic.com notes that falls and motor vehicle crashes contribute to causing this type of aneurysm.
Additional Factors
The National Heart Lung and Blood Institute notes that in rare cases, infections can result in aneurysms. A condition referred to as vasculitis, which is an inflammation and infection of the aortic wall, can result in aortic aneurysm. Genetic conditions such as Marfan syndrome, which affects the connective tissues in the body, is a risk factor for developing an aneurysm. MayoClinic.com explains that Marfan syndrome weakens the aortic walls and increases vulnerability to internal damage or tears to the aorta.
References
- National Heart Lung and Blood Institute: What Causes An Aneurysm?
- Cleveland Clinic: Brain Aneurysm and Hemorrhage
- MedlinePlus: Abdominal aortic aneurysm
- MayoClinic.com: Aortic aneurysm: Causes
- "American Journal of Epidemiology": Smoking, Hypertension, Alcohol Consumption, and Risk of Abdominal Aortic Aneurysm in Men
