No evidence of increased fetal haemoglobin in an adult diabetic population.

Increased fetal haemoglobin levels, which could interfere with glycohaemoglobin assessment, have been observed in some diabetic populations, especially in insulin-treated patients. In this study, we have consecutively examined 1042 adult (aged > 18 y) diabetic subjects (102 IDDM patients, 263 insulin-treated NIDDM patients and 677 non-insulin-treated NIDDM patients) and 156 sex-and age-matched control subjects. Fetal haemoglobin was assessed with a fully automated high performance liquid chromatography (HPLC) device. Its average levels were 0.19% +/- 0.28% in the control group, 0.17% +/- 0.23% in IDDM patients, and 0.19% +/- 0.25% in insulin-treated NIDDM patients; these differences were not significant. Also the percentage of patients with fetal haemoglobin exceeding the 95th percentile of normal values (0.75%) was not different in the various subgroups. In conclusion, in our large cohort of adult diabetic patients, fetal haemoglobin levels are within the normal range, including those who have IDDM or insulin-treated NIDDM. Genetic factors could explain this difference with other reports.