The U.S. Preventative Services Task Force guidelines for abdominal aortic aneurysm (AAA) screening are based mainly on studies of older Caucasian males from non-U.S.This study was designed to analyze the findings of a large, all-inclusive AAA screening program in the U.S.Screening events were held nationally by a U.S. non-profit organization between 2001 and 2017. AAA screening was offered regardless of risk profile. Participants filled out a demographics form with known co-morbidities. Significant risk factors were determined using logistic regression with backward stepwise variable selection. Odds ratios (OR) reported with 95% confidence intervals.A total of 9,457 screened participants (47% male) were analyzed. The mean age was 67 ±9 with 40.8% between 65 and 75 years old. Most participants were Caucasian (83.4%), followed by African American (13.1%). Screened risk factors included hypertension (58.1%), hyperlipidemia (54.9%), smoking (52.0%), cardiac disease (29.2%), diabetes mellitus (18.4%), family history of AAA (22.4%) or brain aneurysms (8.6%), and BMI (26.9 ±5.28). Overall, 267 participants (2.82%) were found to have an AAA (>3cm). Ages 65-75 had a prevalence of 2.98%. In a fully adjusted, multivariate logistic regression, there was an increased risk of AAA in males (OR, 3.24; 2.39-4.40), current smokers (OR, 3.28; 2.36-4.54), previous smokers (OR, 1.86; 1.41-2.47), cardiac disease (OR, 1.30; 1.01-1.68), family history of AAA (OR, 1.60; 1.20-2.14), and increasing age (P <.0001). Female ever smokers 65-75 years old had a prevalence of 1.7%. Male smokers 45-54 and 55- 64 years old had a prevalence of 3.37% and 4.43%, respectively. There was an increased risk of AAA in females with morbid obesity (OR, 5.54; 1.34-22.83 in never smokers and OR, 5.61; 1.04-30.15 in smokers), female smokers with hypertension (OR, 3.22; 1.21-8.58), males with cardiac disease (OR, 2.06; 1.08-3.90 in never smokers and OR, 1.48; 1.05-2.09), male smokers with family history of AAA (OR, 1.69; 1.61-2.46), and current smokers (OR, 6.33; 2.62-15.24 for females and OR, 2.50; 1.70-3.65 for males).This study shows that there remain high-risk groups outside the current guidelines which would likely benefit from AAA screening. Risk factors for AAA include male gender, smoking, cardiac disease, family history of AAA and increasing age. The most significant risk factor is current smoking status.
