Patients who showed paradoxical increase in HbA1c levels after intensification of diabetes treatment

• Paradoxical increase in HbA1c levels sometimes occurs after diabetes treatment.
• In the present study, we investigated the pathophysiology of such situations.
• In such patients, glycemic control got worsened before diabetes treatment.
• Therapeutic effect may be misinterpreted if glycemic control is evaluated by HbA1c.
• It is preferable to evaluate glycemic control by FPG, GA and fructosamine.

ObjectivesWhen diabetes treatment is started, added, or changed (intensification of treatment) in patients with poor glycemic control, GA (glycated albumin) decreases within a few weeks, while HbA1c increases in some patients, resulting in a discrepancy between changes in GA and HbA1c. In the present study, we investigated the pathophysiology of such discrepancies.Design and methodsFour diabetic patients with poor glycemic control in whom GA showed a decrease while HbA1c showed an increase at a few weeks after intensification of treatment, resulting in a discrepancy between the time course of HbA1c and that of GA, were studied.ResultsIn all patients HbA1c increased during the course before intensification of treatment; GA measured in two patients before the intensification of treatment also increased. After the intensification of treatment, GA decreased in all patients. On the other hand, HbA1c increased even after the intensification of treatment, but it decreased later in these patients.ConclusionsIn patients in whom HbA1c increased in spite of a decrease in GA after the intensification of diabetes treatment, glycemic control got worsened before the intensification of treatment. In such patients, therapeutic effect may be misinterpreted if glycemic control is evaluated by HbA1c, and thus it is preferable to evaluate glycemic control by fasting plasma glucose, GA and fructosamine in such situations.