[Persisting hyperlipidemias as risk factors of diabetic macroangiopathy]

Severe forms of arterial occlusive diseases occurred more frequently in 11 insulin-treated diabetics with persisting hyperlipidemia than in 10 control subjects who were 11 years older. Triglycerides and cholesterol of total serum and of VLDL were 2-7 times higher (P less than 0.01); however, LDL-cholesterol was 2 times lower than in control subjects (P less than 0.025). HDL-cholesterol was not significantly different in either group. After insulin administration (81 U/die vs 37 U/die, P less than 0.00251), the increased lipids were only insignificantly reduced, while LDL-cholesterol and the ratio of LDL-/HDL-cholesterol was even increased (P less than 0.0025 and P less than 0.05). In contrast to control subjects, VLDL-cholesterol was positively correlated to the tolbutamide-induced insulin reserve (before insulin administration) and to the diurnal insulin dosage (after insulin administration) (P less than 0.01 and P less than 0.001). The results show that the atherosclerotic risk in diabetics with persisting hyperlipidemia is higher than in control subjects and that the risk is distinguished by increased VLDL-cholesterol in correlation with increased insulin concentrations. Since the atherosclerotic risk is even more accentuated by the fact that insulin administration increases LDL-cholesterol, insulin therapy must be observed carefully in these patients.