In sickle cell anemia, rapid hemoglobin turnover may be present. HbA1C and other glycated hemoglobin assays are not valid in rapid hemoglobin turnover and in abnormal hemoglobin conditions. Fructosamine measurements can be used because of shorter half life of albumin.

HbA1C measurements are NOT ordinarily used to monitor long-term diabetic control in a diabetic with sickle cell anemia.