Lipid risk factors in patients requiring arterial reconstruction

Progressive peripheral atherosclerosis commonly leads to failure of a bypass graft. Lowering blood cholesterol retards coronary atherosclerosis and similar treatment might limit peripheral atherosclerosis. To identify lipid risk factors for peripheral atherosclerosis, 144 patients with peripheral atherosclerosis (98 with severe disease and 46 with stable claudication) and 61 age-matched control subjects were studied. Fasting lipid (cholesterol and triglycerides) and lipoprotein (high-density lipoprotein [HDL], low-density lipoprotein [LDL], and very-low-density lipoprotein [VLDL] cholesterol [C]) levels were measured. The incidence of hypertension and diabetes mellitus, amount of previous tobacco use, and location and severity of the peripheral atherosclerosis were also determined. Patients with peripheral atherosclerosis had higher VLDL-C and lower HDL-C levels than controls had, but serum cholesterol and plasma LDL-C levels were similar. Patients with peripheral atherosclerosis also had a higher incidence of diabetes mellitus and hypertension. Predictors of peripheral atherosclerosis by regression analysis were diabetes mellitus, low HDL-C levels, and tobacco use, with diabetes mellitus being the strongest variable. Peripheral atherosclerosis below the inguinal ligament was strongly predicted by low HDL-C and increased VLDL-C levels but not by increased cholesterol or LDL-C levels. Thus lipid risk factors for peripheral atherosclerosis are different, and attempts at limiting late graft failure by lowering lipid levels should be directed toward these lipoproteins.