Diabetes mellitus, smoking, and the risk for asymptomatic peripheral arterial disease: whom should we screen?

OBJECTIVE To describe coexisting medical conditions and lifestyle factors associated with asymptomatic peripheral arterial disease (PAD) in a population of white, African American, and Hispanic patients. STUDY DESIGN AND SETTING White, African American, and Hispanic patients 50 years or older were recruited for this cross-sectional study from 4 primary care clinics in Houston, TX. Patients with an ankle-brachial index (ABI) < 0.9 and without leg symptoms typical of PAD were diagnosed with asymptomatic PAD. RESULTS 403 patients were screened for PAD. Of these, 25 (6.2%) had asymptomatic PAD. Compared with patients without PAD, diabetes mellitus ([OR] 3.8; 95% CI 1.6, 9.0) and a history of smoking at least 1 pack of cigarettes per day ([OR] 2.5; 95% CI 1.1, 6.0) were significantly associated with asymptomatic PAD. An interaction effect existed between diabetes mellitus and smoking at least 1 pack of cigarettes per day. Diabetes mellitus combined with heavy smoking showed the highest predicted value positive (15%) and the highest specificity (92%). A lack of both demonstrated low rates for predicting asymptomatic PAD (predicted value positive, 1%). CONCLUSION The ankle-brachial index could become routine screening among patients with diabetes mellitus and/or who smoke.