Traditional risk-scoring algorithms, such as Framingham risk score, are known to have low sensitivity for predicting risk of fatal or nonfatal cardiovascular events. Abnormal ABI, which is indicative of underlying PAD, has been shown to be associated with a higher risk of cardiovascular disease. "In our study, we found abnormal ABI to be highly prevalent; 10 percent of our study population ”who were otherwise not known to have coronary heart disease, stroke, diabetes and are not considered at high risk based on Framingham risk assessment ”have underlying PAD," said Murphy.

Researchers reviewed the results from the PEDAL study, a population-based, cross-sectional study of 822 participants (women, 69.7 percent; non-Hispanic white, 89.7 percent) conducted at 23 Legs for Life?® sites nationwide. PEDAL was conducted in 2007 “08 during SIR's Legs for Life?® PAD national public-health screening program. The participants (average age, 64 years) did not have known cardiovascular disease or diabetes and were screened for PAD with an ABI test. Variables to compute Framingham risk scores of the participants were available to calculate 10-year risk of coronary heart disease. Risk was determined to be low, intermediate or high, per Framingham categories. A low Framingham risk score was observed in 256 participants (31.1 percent); of these, 11.3 percent had an abnormal ABI. Of the 414 participants (50.4 percent) with an intermediate Framingham risk score, 12.8 percent had abnormal ABI test results.

Last year, researchers analyzed information from the 1999 “2004 National Health and Nutrition Examination Survey (NHANES) ”a nationally representative cross-sectional survey of the U.S. population for 6,292 men and women ages 40 and older without known history of heart disease, stroke, diabetes or atherosclerotic vascular disease ”along with available data on standard cardiovascular risk factors and screening tests (including the ABI). They found that novel risk factors (those not traditionally considered in the Framingham risk score) are abnormal in up to 45 percent of those not considered high risk for coronary heart events. It was the first time researchers determined the prevalence of PAD in a large population of women and men who were not considered at high risk for cardiovascular disease.

SOURCE Society of Interventional Radiology