Lower extremity arterial disease in older women: the Rancho Bernardo Study

Most studies of lower extremity arterial disease (LEAD) have not included women. To study the frequency of LEAD and its association with cardiovascular disease risk factors and estrogen use in community-dwelling postmenopausal women, we conducted a cross-sectional study of LEAD in 826 women whose average age was 74 years. Cardiovascular disease risk factors and medical history, body mass index (BMI), blood pressure, glucose tolerance, lipids and lipoproteins, and current and past medication use were determined using a standard protocol. Ankle-brachial artery index (ABI) of systolic blood pressure was measured by a trained technician using Doppler ultrasound. LEAD was defined as ABI <0.8. LEAD prevalence increased with age from nearly 5% in the 60-69-year-old group to >25% in women aged 90 and older. In age-adjusted analyses, women with LEAD had significantly lower levels of high-density lipoprotein (HDL) cholesterol, were less likely to exercise regularly, and were less likely to have ever used estrogen replacement therapy. They also had significantly higher levels of blood pressure, low-density lipoprotein (LDL) cholesterol, triglycerides, glucose, and insulin. In multivariate analyses, high HDL cholesterol, regular exercise, and estrogen use were each associated with a reduced risk of LEAD, whereas age, high blood pressure, and abnormal glucose tolerance were each associated with increased risk. Few women (6%) were smokers, but they had twice the risk of LEAD compared with nonsmokers. Estrogen was independently associated with LEAD in a model containing all covariates except LDL and HDL, and this association was no longer significant in a second model adjusting for these lipoproteins. LEAD is common in older women and associated with modifiable risk factors. The apparent protection associated with estrogen should be studied in clinical trials.