Risk factors associated with the diagnosis of abdominal aortic aneurysm in patients screened at a regional Veterans Affairs health care system.

BACKGROUND: An active abdominal aortic aneurysm (AAA) screening program at a regional Veterans Affairs (VA) health system identifies patients at risk for AAA. The purpose of this study is to evaluate unique risk factors associated with the AAA diagnosis upon AAA screening examination to identify the most at risk patients for AAA. METHODS: Data were extracted from a regional VA health care system to identify patients who underwent AAA screening within a 3-year period. An aortic diameter ≥3.0 cm was defined as an AAA. Patient risk factors included age, body mass index, total cholesterol, estimated glomerular filtration rate (eGFR), statin use, and active smoking status; the presence of hypertension, diabetes, coronary artery disease (CAD), chronic obstructive pulmonary disease (COPD), or peripheral vascular disease (PVD) was also evaluated. Risk factors were compared in a multivariate analysis between patients with AAA and patients with a normal aorta. RESULTS: A total of 6,142 patients (mean ± SD age: 72.7 ± 5.3 years) were screened for AAA between January 2007 and December 2009. A total of 469 patients (7.6%) with AAA were identified. The following risk factors were significantly associated with a diagnosis of AAA: age >75 years (39.6% vs. 28.9%; P < 0.001), prevalence of CAD (43.1% vs. 28.5%; P < 0.001), COPD (26% vs. 11.4%; P < 0.001), PVD (37.3% vs. 7.7%; P < 0.001), eGFR <60 mL/min (36.7% vs. 24.3%; P < 0.001), and current smoking (23.2% vs. 15.3%; P < 0.001). The risk factors significantly associated with normal aortic size were the presence of diabetes (18.6% vs. 27.4%; P < 0.001) and total cholesterol ≥200 mg/dL (10.4% vs. 15%; P = 0.04). CONCLUSIONS: The diagnosis of AAA in a large screening study is typically identified in patients who are at high risk for cardiovascular disease. The presence of diabetes is a major cardiovascular risk factor that is more associated with normal aorta when compared to patients with the AAA diagnosis. Total cholesterol ≥200 mg/dL was associated with decreased AAA risk, and renal insufficiency was associated with increased AAA risk.

Outcomes of an abdominal aortic aneurysm screening program.

OBJECTIVE: In 2007, Medicare guidelines were established to identify persons at risk for the presence of an abdominal aortic aneurysm (AAA). The purpose of this study is to evaluate the 5-year outcomes of an AAA screening program in a regional Veterans Affairs (VA) health care system. METHODS: Data were extracted from a regional VA health care network identifying all veteran males 65 to 75 years of age who smoked at least 100 cigarettes during their lifetime. In 2007, an AAA screening mandate was implemented allowing patients meeting screening criteria to be evaluated for AAA as part of the patient's health maintenance. AAA is identified as an aortic diameter size of 3.0 cm or greater. Clinician adherence to screening protocols and referral to a vascular surgeon for aneurysms >5.5 cm were also evaluated. RESULTS: A total of 9751 patients (71.5 ± 5.6 standard deviation years of age) were screened for an AAA over a 5-year period from January 1, 2007 to December 31, 2011. A total of 698 aneurysms (7.1%) were found. Referrals to a vascular surgeon were made on 45 patients with aneurysms >5.5 cm. Over a 5-year period, a total of 2754 patients (28.2%) were inappropriately screened: 416 patients were under 65 years old, 2243 patients were over 75 years old, 36 patients were women, and 123 patients without aneurysms had multiple screenings. In 2007, during the first year of implementation, 39.2% of patients were inappropriately screened. Over the next 4 years, inappropriate screenings decreased with 33.7% in 2008, 28.6% in 2009, 17.7% in 2010, and 14.3% in 2011. CONCLUSIONS: A large AAA screening program at the VA detects more aneurysms, but at smaller diameters than that published in clinical trials. Over time, the number of inappropriate AAA screenings has continued to decrease, demonstrating greater awareness and application of the AAA screening guidelines by primary care providers. Developing surveillance guidelines for small and medium aneurysms is a potential area for future research.