Insulin response to an oral glucose load in relation to Lp(a)/pre-beta 1-lipoprotein levels in non-diabetic patients with peripheral vascular disease and in controls.

An oral glucose tolerance test (OGTT) was performed in 21 patients with previously known or recently detected peripheral vascular disease as well as in 16 age-matched controls. The angiographic results and the results in a physiological investigation were used to classify patients with high and low stenosis and normal controls, respectively. No significant differences in mean levels of insulin and blood glucose were found between patients with high and low stenosis, respectively, or between normal controls and (a) the whole group of patients with high stenosis, (b) only those with high stenosis who had not undergone arterial surgery. However, individuals with high amounts of Lp(a) lipoprotein were found to have significantly lower insulin mean levels during the OGTT and an even lower mean fasting level as compared to individuals without detectable Lp(a) lipoprotein. In the group of individuals with high amounts of Lp(a) lipoprotein, the glucose mean levels were also significantly lower, during a part of the OGTT. These findings are in agreement with previous results and suggest that inherited metabolic differences exist between individuals with high and zero or low levels of Lp(a) lipoprotein.