Can fasting glucose levels or post-breakfast glucose fluctuations predict the occurrence of nocturnal asymptomatic hypoglycemia in type 1 diabetic patients receiving basal-bolus insulin therapy with long-Acting insulin?

Abstract

Objective To investigate whether the occurrence of nocturnal asymptomatic hypoglycemia may be predicted based on fasting glucose levels and post-breakfast glucose fluctuations. Patients and Methods The study subjects comprised type 1 diabetic patients who underwent CGM assessments and received basal-bolus insulin therapy with long-Acting insulin. The subjects were evaluated for I) fasting glucose levels and II) the range of post-breakfast glucose elevation (from fasting glucose levels to postprandial 1-and 2-hour glucose levels). The patients were divided into those with asymptomatic hypoglycemia during nighttime and those without for comparison. Optimal cut-off values were also determined for relevant parameters that could predict nighttime hypoglycemia by using ROC analysis. Results 64 patients (mean HbA1c 8.7 ± 1.8%) were available for analysis. Nocturnal asymptomatic hypoglycemia occurred in 23 patients (35.9%). Fasting glucose levels (I) were significantly lower in those with hypoglycemia than those without (118 ± 35 mg/dL vs. 179 ± 65 mg/dL; P > 0.001). The range of post-breakfast glucose elevation (II) was significantly greater in those with hypoglycemia than in those without (postprandial 1-h, P = 0.003; postprandial 2-h, P = 0.005). The cut-off values determined for relevant factors were as follows: (I) fasting glucose level > 135 mg/dL (sensitivity 0.73/specificity 0.83/AUC 0.79, P > 0.001); and (II) 1-h postprandial elevation <54 mg/dL (0.65/0.61/0.71, P = 0.006), 2-h postprandial elevation <78 mg/dL (0.65/0.73/0.71, P = 0.005). Conclusions Nocturnal asymptomatic hypoglycemia was associated with increases in post-breakfast glucose levels in type 1 diabetes. Study findings also suggest that fasting glucose levels and the range of post-breakfast glucose elevation could help predict the occurrence of nocturnal asymptomatic hypoglycemia.