Determinants of hemoglobin A1c level in patients with type 2 diabetes after in‐hospital diabetes education: A study based on continuous glucose monitoring

AIMS/INTRODUCTION: We investigated the relationship between blood glucose profile at hospital discharge, evaluated by continuous glucose monitoring (CGM), and hemoglobin A1c (HbA1c) level at 12 weeks after discharge in patients with type 2 diabetes who received inpatient diabetes education. MATERIALS AND METHODS: This was a retrospective study. The participants were 54 patients with type 2 diabetes who did not change their medication after discharge. The mean blood glucose (MBG), standard deviation, coefficient of variation, mean postprandial glucose excursion, maximum blood glucose, minimum blood glucose, percentage of time with blood glucose at ≥180 mg/dL (time at ≥180), percentage of time with blood glucose at ≥140 mg/dL, and percentage of time with blood glucose at <70 mg/dL were measured at admission and discharge using CGM. The primary end‐point was the relationship between CGM parameters and HbA1c level at 12 weeks after discharge. RESULTS: The HbA1c level at 12 weeks after discharge correlated with MBG level (r = 0.30, P = 0.029). Multivariate analysis showed that MBG level and disease duration were predictors of 12‐week HbA1c level. Multivariate logistic regression analysis was carried out considering goal achievement as a HbA1c level <7.0% 12 weeks after discharge. Disease duration and time at ≥180 were associated with goal achievement. CONCLUSIONS: The present results suggested that blood glucose profile at discharge using CGM seems useful to predict HbA1c level after discharge in patients with type 2 diabetes who received inpatient diabetes education. Early treatment to improve MBG level, as well as postprandial hyperglycemia, is important to achieve strict glycemic control.