The purpose of this study was to evaluate risk factors associated with peripheral vascular disease (PVD) in patients with non-insulin-dependent diabetes mellitus (NIDDM). A group of 100 patients (50 men and 50 women) aged 50 years or over with PVD and another group of 200 age-sex-matched patients (100 men and 100 women) without PVD were studied. The mean +/- standard error of ages for subjects with and without PVD were 60.8 +/- 0.6 years and 59.7 +/- 0.3 years, respectively. Doppler ultrasound was used to measure the systolic pressures of the brachial, posterior tibial and dorsal pedal arteries bilaterally. The diagnosis of PVD was made by an ankle-brachial index (ABI) < 0.90 and the diagnosis of non-PVD by an ABI > 1.00. The association of PVD with diabetic duration, body mass index (BMI), cerebral infarction (CI), coronary heart disease (CHD), proteinuria, diabetic retinopathy, neuropathy, hypertension, and cigarette smoking was evaluated. In addition, biochemical data including fasting plasma glucose, hemoglobin (HD)Alc, cholesterol, triacylglycerol, high- and low-density lipoprotein cholesterol, uric acid, blood urea nitrogen (BUN) and creatinine (Cr) were studied. In univariate analysis, PVD was associated with an increased level of systolic blood pressure (SBP), BUN and Cr, cigarette smoking, CI, CHD, proteinuria and retinopathy. In stepwise logistic regression analysis, the level of SBP, cigarette smoking and CI remained statistically significant. The log odds of PVD could be expressed as: -2.834 + 0.013 (SBP in mmHg) + 0.577 (cigarette smoking) + 1.320 (CI). PVD is the result of aggregation of atherosclerotic risk factors; among those factors noted in this study, SBP, cigarette smoking and CI are important.