Real-Time Hypoglycemia Prediction Suite Using Continuous Glucose Monitoring

Abstract

OBJECTIVEThe purpose of this study was to develop an advanced algorithm that detects pending hypoglycemia and then suspends basal insulin delivery. This approach can provide a solution to the problem of nocturnal hypoglycemia, a major concern of patients with diabetes.RESEARCH DESIGN AND METHODSThis real-time hypoglycemia prediction algorithm (HPA) combines five individual algorithms, all based on continuous glucose monitoring 1-min data. A predictive alarm is issued by a voting algorithm when a hypoglycemic event is predicted to occur in the next 35 min. The HPA system was developed using data derived from 21 Navigator studies that assessed Navigator function over 24 h in children with type 1 diabetes. We confirmed the function of the HPA using a separate dataset from 22 admissions of type 1 diabetic subjects. During these admissions, hypoglycemia was induced by gradual increases in the basal insulin infusion rate up to 180% from the subject's own baseline infusion rate.RESULTSUsing a prediction horizon of 35 min, a glucose threshold of 80 mg/dl, and a voting threshold of three of five algorithms to predict hypoglycemia (defined as a FreeStyle plasma glucose readings <60 mg/dl), the HPA predicted 91% of the hypoglycemic events. When four of five algorithms were required to be positive, then 82% of the events were predicted.CONCLUSIONSThe HPA will enable automated insulin-pump suspension in response to a pending event that has been detected prior to severe immediate complications.

Continuous Glucose Monitoring: Real-Time Algorithms for Calibration, Filtering, and Alarms

“…Another linear projection method (used in the voting method presented by Cameron and colleagues 40 and Dassau and colleagues 41 and the pump shutoff studies of Buckingham and associates 42 ) is to consider the end points of a data window…”

Artificial Pancreas Using a Personalized Rule-Based Controller Achieves Overnight Normoglycemia in Patients with Type 1 Diabetes

“…The idea of predicting either hypoglycemia or hyperglycemia episodes as a safety alternative has been proposed previously. 26 Our approach is not only to take advantage of glucose prediction to estimate the future rate of change in glucose levels, which was used by the pRBA as a safety constraint, but also to determine the accepted range in glucose stability.…”

A Novel Adaptive-Weighted-Average Framework for Blood Glucose Prediction

“…Dassau et al 17 and Buckingham et al 18 proposed a hypoglycemia prediction algorithm (HPA) combination framework. The core of the framework is a set of individual HPAs that are combined into one algorithm by using a voting scheme.…”

“…The core of the framework is a set of individual HPAs that are combined into one algorithm by using a voting scheme. The HPA system proposed in this study 17 includes five prediction algorithms: linear projection, Kalman filter, hybrid infinite impulse response filter, statistical prediction, and numerical logical algorithm. When a new CGMS datum is available, each alarm will run independently and produce an alarm if a hypoglycemic event is predicted.…”