Abstract

Predictions based on continuous glucose monitoring (CGM) data are the basis for automatic suspension and resumption of insulin delivery by a predictive low-glucose management feature termed "suspend before low," which is part of the Medtronic MiniMed(®) 640G combined insulin pump and CGM system. This study assessed the safety and performance characteristics of the system in an in-clinic setting at eight sites.In-clinic standardized increases in basal insulin delivery rates were used to induce nocturnal hypoglycemia in subjects (14-75 years) with type 1 diabetes wearing the MiniMed 640G system. The "suspend before low" feature was set at 65?mg/dL, and as a result, the predictive algorithm suspended insulin delivery when the forecasted glucose was predicted to be =85?mg/dL in 30?min (a 20?mg/dL safety buffer). Reference plasma glucose values (Yellow Springs Instruments [YSI], Yellow Springs, OH) were used to establish hypoglycemia and were defined as =2 consecutive values =65?mg/dL.Eighty subjects were screened. Among the 69 successful completers, 27 experienced a hypoglycemic event and 42 did not, a prevention rate of 60%. The mean (±standard deviation) YSI value at the time of pump suspension was 101?±?18.5?mg/dL, and the mean duration of the 68 "suspend before low" events was 105?±?27?min. At 120?min after the start of the pump suspension events, the mean YSI value was 102?±?34.6?mg/dL.The MiniMed 640G "suspend before low" feature prevented 60% of induced predicted hypoglycemic events without significant rebound hyperglycemia.

View details for DOI 10.1089/dia.2016.0319

View details for PubMedID 28221823