[Changes in magnesium and ionized calcium serum levels in disorders of glucose tolerance]

In a group of 58 subjects with a strictly defined glucose tolerance (38 normal--nGT, 10 impaired glucose tolerance--pGT, 10 type II diabetics treated by diet) the authors investigated the mutual relationship between changes in the blood sugar level and insulin serum level in relation changes of calcium, ionized calcium, magnesium and total proteins. In addition to expected differences in the native blood sugar level and insulinaemia, the authors found in pGT group in reduction of ionized calcium and magnesium on fasting. In the course of the oGTT in pGT group there is a rise of ionized calcium and magnesium and thus the changes, as compared with the initial value, differ significantly from changes in subjects with a normal glucose tolerance and in type II diabetics. The differences in the pattern total calcium are less marked, the changes of total protein did not differ. Evaluation of correlations revealed a only significant relationship between the change of ionized calcium and blood sugar level after 120 mins, in DM II. The findings suggest a different calcium and magnesium metabolism after a glucose load in subjects with an impaired glucose tolerance. It is not clear whether a cause of the disorder is involved or a possible compensatory mechanism. The clinical impact will have to be examined.