[Risk factor, natural history and prognosis of the patients with arteriosclerosis obliterans].

A sufficient understanding of the risk factor and the natural history of arteriosclerosis obliterans, ASO, is essential for selecting the optimal treatment for this condition. Hypercholesterolemia, hypertension and cigarette smoking have been identified as independent major risk factors of ASO, and diabetics, obesity, hypertrigriceridemia, low HDL-cholesterol level, aging, gender, etc, as minor factors. The patients with ASO often have multiple risk factors, synergistically accelerating the disease progression. Recent objective studies on natural history of claudicants have demonstrated a more morbid prognosis, especially in the patients with disabling claudication, than that outlined by previous historical studies. Mortality rates for ASO patients in long-term follow-up have revealed to be significantly higher than those observed in control groups. The causes of death are mostly arteriosclerotic vascular disease, particularly coronary artery and cerebrovascular diseases, which indicate the significance of the systemic evaluation in treating patients with ASO.