Asymptomatic PAD prevalence on rise; obese women at high risk

Asymptomatic peripheral artery disease (PAD) is becoming more prevalent, and at least among women, is associated with a significantly higher prevalence of obesity, Andrew D. Sumner, MD, said.

He and colleagues compared PAD prevalence in each of the three most recent National Health and Nutrition Examination Surveys (NHANES), conducted in 1999-2000, 2001-2002, and 2003-2004.

A PAD diagnosis was considered to be an ankle-brachial index of less than 0.9. Prevalence of cardiovascular risk factors (obesity, diabetes, hypertension, and smoking) was examined in 5376 participants age 40 years or older with no history of cardiovascular disease.

Prevalence of asymptomatic PAD increased significantly among asymptomatic adults age 40 years or older over the three surveys.

• In the 1999-2000 survey, asymptomatic PAD prevalence was 3.7%.
• In the 2001-02 survey, prevalence of PAD was 4.2%.
• In the most recent survey (2003-04), 4.6% of the participants were diagnosed with asymptomatic PAD.

The increase in PAD prevalence was observed in every age group. The prevalence of asymptomatic PAD was highest among those age 70 years or older (15.0%) and among non-Hispanic blacks.

The prevalence of PAD decreased in men but increased in women during the 6-year period.

"The increasing prevalence of asymptomatic PAD seen in women during the 6-year study was associated with an increase in the prevalence of obesity, while the prevalence of other cardiovascular disease risk factors in women with asymptomatic PAD decreased over the study period," said Dr Sumner, medical director of Heart Station and Cardiac Prevention at Lehigh Valley Hospital, Allentown, PA.

Of the women with asymptomatic PAD, 47% met the criteria for obesity in the 2003-04 survey but only 32% of the women with PAD in the 1999-2000 were considered obese.

Because PAD portends a higher risk of future MI and stroke, identifying PAD before symptoms appear is important to institute early aggressive intervention, Dr Sumner said. Based on the results of the NHANES analysis, physicians should have a high index of suspicion for PAD in obese women who may deserve special screening consideration. PAD is considered a coronary heart disease equivalent in the National Cholesterol Education Program Adult Treatment Panel III guidelines, and therefore warrants secondary prevention treatment measures that include more aggressive lipid goals than those for primary prevention, he added.