Physiological Adaptation Q 192

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What is the most common cause of an abdominal aortic aneurysm?

  

     A. Atherosclerosis

     B. DM

     C. HPN

     D. Syphilis

    

    

Correct Answer: A. Atherosclerosis

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Atherosclerosis accounts for 75% of all abdominal aortic aneurysms. Plaques build up on the wall of the vessel and weaken it, causing an aneurysm. AAA is thought to be a degenerative process of the aorta, the cause of which remains unclear. It is often attributed to atherosclerosis because these changes are observed in the aneurysm at the time of surgery.

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Option B: Diabetes mellitus does not directly cause an abdominal aortic aneurysm. Patients at greatest risk for AAA are men who are older than 65 years and have peripheral atherosclerotic vascular disease. A history of smoking often is elicited.

Option C: Hypertension accounts for 1-15% of cases of an abdominal aneurysm. A Swedish study showed that instances of AAA in elderly men have been decreasing, A phenomenon that can be attributed to a nationwide decline in smoking for the past 30 years, as well as the significantly improved longevity of the elderly population.

Option D: Syphilis is not related to AAA. Syphilis is a bacterial infection usually spread by sexual contact. The disease starts as a painless sore — typically on your genitals, rectum, or mouth. Syphilis spreads from person to person via skin or mucous membrane contact with these sores.

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