Toward Defining the Threshold Between Low and High Glucose Variability in Diabetes

Diabetes Care. 2017 Jul;40(7):832-838. doi: 10.2337/dc16-1769. Epub 2016 Dec 30.

Abstract

Objective: To define the threshold for excess glucose variability (GV), one of the main features of dysglycemia in diabetes.

Research design and methods: A total of 376 persons with diabetes investigated at the University Hospital of Montpellier (Montpellier, France) underwent continuous glucose monitoring. Participants with type 2 diabetes were divided into several groups-groups 1, 2a, 2b, and 3 (n = 82, 28, 65, and 79, respectively)-according to treatment: 1) diet and/or insulin sensitizers alone; 2) oral therapy including an insulinotropic agent, dipeptidyl peptidase 4 inhibitors (group 2a) or sulfonylureas (group 2b); or 3) insulin. Group 4 included 122 persons with type 1 diabetes. Percentage coefficient of variation for glucose (%CV = [(SD of glucose)/(mean glucose)] × 100) and frequencies of hypoglycemia (interstitial glucose <56 mg/dL [3.1 mmol/L]) were computed.

Results: Percentages of CV (median [interquartile range]; %) increased significantly (P < 0.0001) from group 1 (18.1 [15.2-23.9]) to group 4 (37.2 [31.0-42.3]). In group 1, the upper limit of %CV, which served as reference for defining excess GV, was 36%. Percentages of patients with %CVs above this threshold in groups 2a, 2b, 3, and 4 were 0, 12.3, 19.0, and 55.7%, respectively. Hypoglycemia was more frequent in group 2b (P < 0.01) and groups 3 and 4 (P < 0.0001) when subjects with a %CV >36% were compared with those with %CV ≤36%.

Conclusions: A %CV of 36% appears to be a suitable threshold to distinguish between stable and unstable glycemia in diabetes because beyond this limit, the frequency of hypoglycemia is significantly increased, especially in insulin-treated subjects.

MeSH terms

  • Aged
  • Blood Glucose*
  • Diabetes Mellitus, Type 1 / blood*
  • Diabetes Mellitus, Type 1 / drug therapy
  • Diabetes Mellitus, Type 2 / blood*
  • Diabetes Mellitus, Type 2 / drug therapy
  • Dipeptidyl-Peptidase IV Inhibitors / pharmacology
  • Dipeptidyl-Peptidase IV Inhibitors / therapeutic use
  • Female
  • Humans
  • Hypoglycemia / blood
  • Hypoglycemia / drug therapy
  • Hypoglycemic Agents / pharmacology*
  • Hypoglycemic Agents / therapeutic use
  • Insulin / pharmacology
  • Insulin / therapeutic use
  • Male
  • Middle Aged
  • Sulfonylurea Compounds / pharmacology*
  • Sulfonylurea Compounds / therapeutic use
  • Treatment Outcome

Substances

  • Blood Glucose
  • Dipeptidyl-Peptidase IV Inhibitors
  • Hypoglycemic Agents
  • Insulin
  • Sulfonylurea Compounds