Insulin reserves in children with impaired glucose tolerance(IGT) and subsequent development of diabetes mellitus (DM)

Abstract

The validity of the maximum stimulation test (MIST) and oral glucose tolerance test(OGTT) as screening procedures for the development of DM was studied in 33 children with IGT. They were administered MIST(p.o.glucose;i.v.tolbutamide and glucagon) and OGTT on 2 consecutive days.Insulin response was compared with the development of DM for up to 5½yrs.MIST was a better indicator of the chance to develop DM:3 non-obese subjects with poor MIST insulin response (glucose/insulin ratio> 4)developed DM. One child who was on Orinase at the time of studies,progressed to DM despite a good MIST insulin release.All others had a good MIST insulin response and did not develop DM.The predictive value for the development of DMwith a poor MIST insulin response was 75%.The predictive value for non-development of DM with a good MIST insulin response was 96.2%.In contrast,OGTT elicited poor insulin responses in 9 of 30 children;only 3 of them progressed to DM.The predictive value for development of DM with a poor OGTT insulin response at 1 hr was 33.3% and the predictive value for non-development of DM with a good OGTT insulin release was 100%.Thus, the ability to release insulin during MIST may be a better prognostic indicator of the chance to develop DM in children with IGT,whereas OGTT may help in assessing the decreased risk of DM.