Progression of peripheral occlusive arterial disease in diabetes mellitus. What factors are predictive? The clinical, biochemical, and vascular laboratory measurements potentially associated with the development and/or progression of peripheral occlusive arterial disease (POAD) were assessed during a 4-year period in 110 normal control subjects, 112 patients with POAD without diabetes mellitus, 240 patients with diabetes mellitus without POAD, and 100 patients with diabetes mellitus and POAD. Age, history of hypertension or coronary heart disease, history of cigarette smoking, presence of POAD, systolic blood pressure, and beta-thromboglobulin level were associated with progression of POAD. A multivariate logistic regression model indicated that the presence of diabetes mellitus or POAD or both at baseline, decreased postexercise ankle-brachial index, increased arm systolic blood pressure, and current smoking were independently associated with progression of POAD. This study suggests that cessation of smoking and control of hypertension are essential treatment modifications to decrease the risk of progression of peripheral vascular disease in diabetic patients. 