Glucose variability indices predict the episodes of nocturnal hypoglycemia in elderly type 2 diabetic patients treated with insulin

Diabetes Metab Syndr. 2017 Apr-Jun;11(2):119-124. doi: 10.1016/j.dsx.2016.08.023. Epub 2016 Aug 23.


Aim: O determine the applicability of glucose variability (GV) indices derived from continuous glucose monitoring (CGM) data for prediction of nocturnal hypoglycemia (NH) in elderly patients with type 2 diabetes treated with insulin.

Methods: We observed 83 insulin-treated in-patients, 65-80 years of age. Blinded CGM data for 176 nights were analyzed. Daytime (06:00-22:59) mean glucose, Standard Deviation (SD), 2-h Continuous Overlapping Net Glycemic Action (CONGA2) and Mean Absolute Glucose (MAG), pre-midnight (23:00-23:59) mean glucose, SD and MAG, 24-h Mean Amplitude of Glucose Excursions (MAGE), were estimated. Pre-midnight glucose trends were estimated as the absolute difference between glucose values at 23:00 and 23:59 (deltaG). Episode of interstitial glucose ≤70mg/dL observed from 0:00 to 5:59 was considered as NH.

Results: NH was present in 68 out of 176 24-h recordings (39%). Lower daytime mean glucose and CONGA2, and higher MAG values were found in patients with NH as compared to those without (p=0.0002, p=0.0001 and p=0.02, respectively). Pre-midnight mean glucose was lower, while pre-midnight deltaG was higher in patients with NH (p<0.0001 and p=0.02). Antecedent daytime hypoglycemia increased the risk of NH (p<0.0001). In logistic regression analysis, the combination of daytime MAG and pre-midnight mean glucose was the most reliable predictor of subsequent NH (accuracy 75.6%, p=0.0004).

Conclusion: The analysis of CGM-derived GV parameters could improve prediction of NH in elderly patients with type 2 diabetes treated with insulin.

Keywords: Continuous glucose monitoring; Glucose variability; Hypoglycemia; Type 2 diabetes.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Blood Glucose*
  • Diabetes Mellitus, Type 2 / blood*
  • Diabetes Mellitus, Type 2 / drug therapy
  • Female
  • Humans
  • Hypoglycemia / blood*
  • Hypoglycemia / chemically induced
  • Hypoglycemic Agents / adverse effects*
  • Insulin / adverse effects*
  • Male
  • Monitoring, Physiologic
  • Risk Assessment


  • Blood Glucose
  • Hypoglycemic Agents
  • Insulin