Increased Fetal Hemoglobin in Insulin-Treated Diabetes Mellitus Contributes to the Imprecision of Glycohemoglobin Measurements

been described in pediatric insulin-dependent patients. The popular electroendosmotic method for glycohemo-globin includes HbF. In an adult population comprising 50 insulin-treated and 57 non-insulin-treated diabetic pa-tients and 57 control subjects, we measured HbF by HPLC and measured glycohemoglobin by both HPLC and an electroendosmotic method. Of the insulin-treated pa-tients, 46 % had concentrations of HbF 0.5%, compared with 25 % of non-insulin-treated patients and 23 % of controls (P <0.02). In the insulin-treated patients, the two glycohemoglobin methods correlated best when the HPLC measurements included HbF (r = 0.92 vs r = 0.84). Fructosamine concentrations correlated best with glyco-hemoglobin concentrations determined by methods that accounted for HbF. The true between-batch CV of th