Objective To investigate the prevalence of vascular disease in the lower extremities and its related risk factors in type 2 diabetic patients.Methods A total of 393 type 2 diabetic patients treated in 5 hospitals in Beijing were randomly recruited for the study with their age of more than 40 years at onset,diabetes duration of more than 5 years and treatment for more than 1 year in each hospital.The case history,physical examination,biochemical tests and ultrasonic Doppler examination were conducted in these patients.Results Eight patients had gangrene (2.0%) and 28(7.1%) had intermittent claudication in 393 diabetics,while ultrasonic examination showed that 357 cases (90.8%) had vascular lesions in the lower limbs.Ankle/brachial systolic pressure ratio (API,Ankle pressure index) less than 1.0 was found in 68 cases (17.8%).The higher prevalence of diabetic nephropathy and retinopathy,higher fasting blood sugar and HbAlc,higher diastolic pressure and lower HDL ch levels ( P