Résumé
•Reducing glycemia to near normal levels in type 1 diabetes is associated with an increased risk for hypoglycemia.•The time spent with glucose below 70 mg/dL (TBR < 70 mg/dL) is positively correlated with the glycemic variability (%CVglucose).•The risk for hypoglycemia becomes negligible or eliminated when the %CVglucose are < 27 or 19%, respectively.•One of the ultimate goals of the treatment in type 1 diabetes is to achieve a near normal glycemic variability.•The latter objective remains far from being attainable even with the most current new technologies of insulin delivery.
Lowering plasma glucose to near normal levels without consideration of the within-day glycemic variability is a potential risk factor for iatrogenic hypoglycemia in type 1 diabetes.
To know below which threshold the glycemic variability should be brought for minimizing or eliminating the risk of hypoglycemia in type 1 diabetes treated with SAP (Sensor Augmented Pump) or AID (Automated Insulin Delivery).
The analysis of 38 randomized controlled trials has shown a mean reduction of 2.0 % (percentage points) in the coefficient of variation for glucose (%CV glucose) is associated with a mean decrease in the percentage of time spent with plasma glucose levels below 70 mg/dL (TBR < 70 mg/dL) of approximately 0.50 % (percentage points). In addition, the risk for hypoglycemia becomes negligible or eventually eliminated according to whether the %CV glucose is brought down below 27 or 19 %, respectively.
As such thresholds are the upper limit or the averaged value of %CV glucose, respectively, in non-diabetic people, the ultimate goal to prevent hypoglycemia in people with type 1 diabetes on intensive insulin therapy should be to achieve a near normal glycemic variability. Achieving such a goal needs further improvements in insulin delivery systems.