Contribution of fasting and postprandial hyperglycemia to hemoglobin A 1c in insulin-treated Japanese diabetic patients

Abstract

The contribution of fasting and postprandial glucose to hemoglobin A 1c (HbA1c) levels was evaluated in insulin-treated patients. In 57 insulin-treated, diabetic out-patients, fasting glucose (before breakfast (B-FG), lunch (L-FG) and dinner (D-FG)) and postprandial glucose (B-PPG, L-PPG and D-PPG) levels were determined by the patients themselves at home using glucose self-monitoring apparatus over the course of one week. The correlation between HbA1c levels and self monitored blood glucose levels were calculated. In the conventionally treated group, there was a significant correlation between HbA1c and fasting glucose (FG) levels only before lunch, but at 2 hr after (PPG) all meals. In the intensively treated group, a significant correlation between HbA1c levels and FG levels was found before lunch and at 2 hr after breakfast and dinner. In all subjects, only FG levels before lunch correlated significantly with HbA 1c levels, although PPG levels were significantly correlated with HbA1c at all points. The correlation was highest with PPG after breakfast and dinner. The sum of all FG, PPG and FG + PPG levels was significantly correlated with HbA1c levels. Postprandial hyperglycemia after breakfast and dinner should be regarded as most important for improving HbA1c levels in insulin treated diabetic patients.