AbstractThe effects of plasma lipid reduction on the progression of femoral atherosclerosis have been studied in 24 hyperlipidaemic patients with stable intermittent claudication. The patients were randomized into treatment or ‘usual‐care’ groups, the former receiving lipid‐lowering therapy by diet and drugs, and the latter no such treatment. Biplanar femoral arteriography was performed before and after a mean period of 19 months. In the treatment group plasma total cholesterol was decreased by a mean of 25 per cent and plasma triglyceride by more than 40 per cent. Plasma lipids were unchanged in the usual‐care group. Significantly fewer arterial segments showed detectable progression in the treatment group (P<0·01). In addition, the mean increment in plaque area (mm2per segment per year) in the treatment group was only 34 per cent of that in the usual‐care grou