[Epidemiology and natural history of arterial diseases of the lower limbs].

Symptomatic arterial disease in the legs is common and asymptomatic disease is even more common. However the majority of these patients do not develop disabling intermittent claudication and the local disease tends to run a benign course, particularly in women, with less than 10% to 15% ever requiring active intervention. With current therapy the incidence of major amputation is only 1% to 3%. By contrast however the very few patients who develop critical leg ischaemia have a prognosis as serious of that as an incurable malignant cancer. Only little over half of these patients will be alive without a major amputation a year after developing critical leg ischaemia. Perhaps the most important results of epidemiological studies in patients with arterial disease in the legs is that both symptomatic and asymptomatic disease increases mortality by a factor of 2 to 3 compared to subjects without significant arterial disease in the legs. One obvious implication of this is the need to redirect attention to the secondary prevention of cardiovascular morbidity or mortality in these patients even though their symptoms may be confined to the leg.