Bruce A Buckingham1, Timothy S Bailey2, Mark Christiansen3, Satish Garg4, Stuart Weinzimer5, Bruce Bode6, Stacey M Anderson7, Ronald Brazg8, Trang T Ly1, Francine R Kaufman9. 1. 1 Department of Pediatric Endocrinology, Stanford University , Stanford, California. 2. 2 AMCR Institute , Escondido, California. 3. 3 Diablo Clinical Research , Walnut Creek, California. 4. 4 Barbara Davis Center for Diabetes , Aurora, Colorado. 5. 5 Department of Pediatrics, Yale University School of Medicine , New Haven, Connecticut. 6. 6 Atlanta Diabetes Center , Atlanta, Georgia . 7. 7 UVA Center for Diabetes Technology , Charlottesville, Virginia. 8. 8 Rainier Clinical Research Center , Renton, Washington. 9. 9 Medtronic, Northridge, California.
Abstract
BACKGROUND: 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. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSION: The MiniMed 640G "suspend before low" feature prevented 60% of induced predicted hypoglycemic events without significant rebound hyperglycemia.
BACKGROUND: 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. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSION: The MiniMed 640G "suspend before low" feature prevented 60% of induced predicted hypoglycemic events without significant rebound hyperglycemia.
Authors: J Geoffrey Chase; Jean-Charles Preiser; Jennifer L Dickson; Antoine Pironet; Yeong Shiong Chiew; Christopher G Pretty; Geoffrey M Shaw; Balazs Benyo; Knut Moeller; Soroush Safaei; Merryn Tawhai; Peter Hunter; Thomas Desaive Journal: Biomed Eng Online Date: 2018-02-20 Impact factor: 2.819
Authors: Jane L Chiang; David M Maahs; Katharine C Garvey; Korey K Hood; Lori M Laffel; Stuart A Weinzimer; Joseph I Wolfsdorf; Desmond Schatz Journal: Diabetes Care Date: 2018-08-09 Impact factor: 19.112
Authors: Rayhan A Lal; Marina Basina; David M Maahs; Korey Hood; Bruce Buckingham; Darrell M Wilson Journal: Diabetes Care Date: 2019-09-23 Impact factor: 19.112