Glycosylated haemoglobin in children with insulin-dependent diabetes mellitus.

Glycosylated haemoglobin (HbA1) was measured serially by microcolumn chromatography in 38 children with newly diagnosed insulin-dependent diabetes. Initial HbA1 levels of 13.6 +/- 0.5% fell signficiantly from day 0 (prior to therapy) both to day 1 (1.6 +/- 0.2% decrease) and to day 3-5 (2.6 +/- 0.4% decrease) (P < 0.001). This drop correlated closely with changes in blood glucose (P < 0.001), less closely and inversely with plasma bicarbonate levels (P < 0.01), but not with prior duration of symptoms or changes in serum cholesterol and triglyceride concentrations. HbA1 levels reached a nadir of 8.2 +/- 0.3% 3 weeks to 6 months after diagnosis, and correlated with decreasing insulin dosage (P < 0.001). HbA1 levels rose again to 11.4 +/- 0.5% in 21 patients followed for more than 3-6 months. Our results indicate that (1) HbA1 level change rapidly during initial stabilization of insulin-dependent diabetes suggesting that glycosylation may not be entirely irreversible, and (2) HbA1 levels are consistent with clinical assessment of control during remission and postremission phases.