Lower extremity atherosclerosis-occlusive disease (PAD) is caused by the formation of atherosclerotic plaques in the lower extremities, resulting in narrowing and occlusion of the lower extremity arteries, which in turn leads to chronic ischemia in the limbs. With the improvement of the overall living standard of the society and the aging of the population, the incidence of lower extremity atherosclerosis occlusive disease is increasing year by year. What are the causes of lower extremity atherosclerosis and occlusive disease? 1, long-term hypertension can cause damage to the inner wall of the blood vessels, which is conducive to lipid infiltration and deposition in the inner wall of the arteries; diabetes can accelerate the process of atherosclerosis occlusion, while there are diabetic microangiopathy to make the condition more complicated. 2, gender and sex hormones: estrogen has the effect of lowering blood lipids and inhibiting atherosclerosis, so the onset of the disease is more frequent in men than in women, and the age of onset is also earlier than in women. 3, the diet contains more saturated fat, eat too much sugar may cause high cholesterol, high blood fat, these also constitute the risk factors of atherosclerosis. 4, smoking: carbon monoxide in cigarettes can cause endothelial cells in the blood vessel wall to lack oxygen, contributing to atherosclerosis; nicotine in cigarettes can also reduce high-density lipoprotein and increase low-density lipoprotein, thus aggravating atherosclerosis, which is one of the main risk factors for atherosclerosis. 5, age: the majority of atherosclerosis develops after the age of 50, mainly due to hypertension, diabetes and some other basic lesions gradually develop and worsen with age. 6, environment: cold, wet environment is prone to the onset of the disease, so the incidence is higher in the northeast, and the incidence will cluster higher every winter.