A 61-year-old man comes to the emergency department complaining of nausea and right upper-quadrant abdominal discomfort for 3 days. His other medical problems include hypertension, type 2 diabetes, hypercholesterolemia, and hypothyroidism. His medications include low-dose aspirin, metformin, glipizide, hydrochlorothiazide, lisinopril, atorvastatin, and levothyroxine. He is an active smoker with a 60-pack-year history and drinks 1-2 glasses of wine daily.
His blood pressure is 155/90 mm Hg and pulse is 80/min. Examination shows no abnormalities.
Laboratory results are as follows:

Ultrasound examination shows several small gallstones without cholecystitis and a 3.8-cm abdominal aortic aneurysm.
Which of the following is associated with the highest rate of aneurysm expansion and rupture in this patient?

Question

A 61-year-old man comes to the emergency department complaining of nausea and right upper-quadrant abdominal discomfort for 3 days.  His other medical problems include hypertension, type 2 diabetes, hypercholesterolemia, and hypothyroidism.  His medications include low-dose aspirin, metformin, glipizide, hydrochlorothiazide, lisinopril, atorvastatin, and levothyroxine.  He is an active smoker with a 60-pack-year history and drinks 1-2 glasses of wine daily.
His blood pressure is 155/90 mm Hg and pulse is 80/min.  Examination shows no abnormalities.
Laboratory results are as follows:

Ultrasound examination shows several small gallstones without cholecystitis and a 3.8-cm abdominal aortic aneurysm.
Which of the following is associated with the highest rate of aneurysm expansion and rupture in this patient?

Quizplus · Accepted Answer

Abdominal aortic aneurysms (AAAs) are usually asymptomatic and are found incidentally on imaging studies done for unrelated reasons. Risk factors associated with AAA development include age > 60, male gender, cigarette smoking, white race, atherosclerosis, and family history of AAA. The diameter can increase progressively and lead to potentially life-threatening rapid aneurysmal expansion and rupture. The major risk factors associated with aneurysmal expansion and rupture include large diameter (> 5.5 cm), expansion rate of > 0.5 cm every 6 months or > 1 cm per year, and active cigarette smoking. Active smoking is associated with the highest rate of aneurysmal expansion and rupture. The mechanism is unclear but likely involves connective tissue degeneration in the aortic wall. Elective repair is preferred for prevention of AAA rupture. Due to operative risk, repair is usually not recommended in asymptomatic patients until the aneurysm diameter is > 5.5 cm (when the risk of rupture exceeds risks of repair). (Choice B & C) Chronic kidney disease and alcohol consumption are not associated with risk of aneurysmal dilation and rupture. (Choice D) Hyperlipidemia is an important modifiable risk factor in patients with atherosclerosis but has not been associated with increased risk for aneurysmal growth and expansion. Statin use has not been shown to reduce the rate of AAA expansion in multiple studies. (Choice E) Diabetes is a strong risk factor for atherosclerosis. However, diabetes mellitus is actually associated with a decreased risk for developing an AAA or expansion of an existing AAA. Educational objective: Observational studies have shown that the strongest predictors of abdominal aortic aneurysm (AAA) expansion and rupture are large aneurysm diameter, rapid rate of expansion, and active cigarette smoking. Active cigarette smoking is associated with the highest rate of aneurysmal expansion and rupture. Referral for AAA repair is recommended for asymptomatic patients with aneurysmal diameter > 5.5 cm. __________ References: Analysis of risk factors for abdominal aortic aneurysm in a cohort of more than 3 million individuals. (http://www.ncbi.nlm.nih.gov/pubmed/20630687) Abdominal aortic aneurysm expansion: risk factors and time intervals for surveillance. (http://www.ncbi.nlm.nih.gov/pubmed/15210603)

A 61-Year-Old Man Comes to the Emergency Department Complaining of Nausea