DIGOXIN-LIKE IMMUNOACTIVITY AND GLUCOSE-TOLERANCE IN PREGNANCY

The relation of fasting plasma digoxin-like immunoactivity (DLIA) to p lasma glucose levels, insulin response as well as to insulin/glucose ( I/G) ratios during 75 g oral glucose tolerance test (OGTT), were inves tigated in 25 pregnant women with different glucose tolerance. There w ere 13 women with normal glucose tolerance (NGT), 12 women had impaire d glucose tolerance (IGT) or gestational diabetes mellitus (GDM). The test was performed after 25 weeks of pregnancy. Fasting plasma DLIA in IGT+GDM was significantly higher (p<0.05) than in NGT pregnant women. In addition, for all the pregnant women, there were direct correlatio ns between fasting plasma DLIA and plasma glucose levels, (most signif icant with increase (delta) in plasma glucose during 1st hour, r=0.65, p<0.001), between fasting plasma DLIA and insulin response, (most sig nificant with 2nd hour insulinemia, r=0.62, p<0.001) as well as betwee n fasting plasma DLIA and I/G ratios, (most significant with 2nd hour I/G ratio, r=0.58, p<0.01), during OGTT. Conversely, the higher the fa sting plasma DLIA, the worse the glucose tolerance and the higher insu lin resistance were observed in pregnant women during OGTT. Correlatio n coefficients describe relationships, but they do not define causalit y. Consequently, it is too early to speculate whether increase in subs tances with DLIA leads to deterioration of glucose tolerance (insulin resistance), or vice versa. Actually, both variables may be secondary to a more basic defect.