[Prediction of nocturnal hypoglycaemia with bedtime glucose level during continuous subcutaneous insulin infusion in type 2 diabetics].

OBJECTIVE

To find out the features of glycemic excursion via continuous glucose monitoring system (CGMS) during continuous subcutaneous insulin infusion (CSII) treatment in type 2 diabetics and discuss the possibility of predicting nocturnal hypoglycaemia with bedtime glucose level.

METHODS

A total of 257 diabetes patients (156 males and 101 females, aged from 27 - 88 years old) with 0.1 - 40 years diabetic history were recruited. Their HbA1c level was (10.97 ± 2.11)%. Glycated albumin level was (31.88 ± 7.51)%. All patients were switched to CSII therapy while a 72-hour period of CGMS was performed. Participants were divided into hypoglycemia group and non-hypoglycemia group according to the reading of hypoglycemic events from CGMS data.

RESULTS

(1) From CGMS profiles, the investigators found that MBG was (9.66 ± 2.00) mmol/L and SDBG (2.98 ± 1.03) mmol/L. (2) A total of 243 hypoglycemia events occurred in 118 participants at early stage of CSII treatment. (3) When bedtime blood glucose was below 5.9 mmol/L, the youden index was maximal on a receiver operating characteristic curve. The sensitive was 54.8% and specificity 77.8%. Positive predictive value was 44.3% and negative predictive value 84.2%. So the cut-off point of bedtime blood glucose to predict nocturnal hypoglycemia might be 5.9 mmol/L.

CONCLUSIONS

(1) Hypoglycemia as detected by CGMS occurs in almost 1/2 type 2 diabetics during CSII therapy. (2) There is a higher risk of nocturnal hypoglycemia if the bedtime blood glucose concentration falls below 5.9 mmol/L.