Hybrid Closed-Loop Control With Prandial Insulin Dosing Informed by Insulin Sensitivity in Adolescents With Type 1 Diabetes
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 25
- 试验地点
- 2
- 主要终点
- Low Blood Glucose Index (LBGI)
研究概览
简要总结
The objective of this study is to evaluate the safety and feasibility of a smart bolus calculator that adjusts insulin dosing for meals according to real-time insulin sensitivity (SI) in adolescents with type 1 diabetes (T1D) using a hybrid closed loop (HCL) system during an active week of diabetes camp.
详细描述
This is a single center, double-blind, randomized, crossover trial. The study team will target enrollment of 30 adolescents (age 12 - <18 years) with T1D who currently manage their diabetes with an insulin pump and a continuous glucose monitoring (CGM) system. Participants will be randomized 1:1 to the use of the standard HCL system (USS Virginia) vs. the HCL system with the smart bolus calculator first. The trial will be held at a local camp facility and will consist of EITHER a weeklong (6 day/5 night) camp OR two long weekends (4 day/3 night) separated by a washout period of about one week.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Treatment
- 盲法
- Double (Participant, Investigator)
入排标准
- 年龄范围
- 12 Years 至 17 Years（Child）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age ≥12 and <18 years old at time of consent
- •Clinical diagnosis, based on investigator assessment, of T1D for at least one year
- •Currently using insulin for at least six months
- •Currently using an insulin pump for at least three months
- •Currently using a CGM system for at least three months
- •Having at least 75% of CGM data over the previous four weeks
- •Using insulin parameters such as carbohydrate ratio and correction factors consistently on their pump in order to dose insulin for meals or corrections
- •Access to internet and willingness to upload data during the study as needed
- •For females, not currently known to be pregnant or breastfeeding
- •A negative urine pregnancy test will be required for all females of childbearing potential
- •Willingness to suspend use of any personal CGM for the duration of the clinical trial once the study CGM is in use
- •Willingness to switch to lispro (Humalog) or aspart (Novolog) if not using already, and to use no other insulin besides lispro (Humalog) or aspart (Novolog) during the study
- •Total daily insulin dose (TDD) of at least 10 U/day
- •Willingness not to start any non-insulin glucose-lowering agent during the course of the trial (including metformin, GLP-1 agonists, pramlintide, DPP-4 inhibitors, biguanides, sulfonylureas and naturaceuticals)
- •Willingness to eat at least 40 grams of carbohydrates per meal
- •An understanding and willingness to follow the protocol and signed informed consent
- •Participants and parent/legal guardians will be proficient in reading and writing in English
- •Willingness to comply with COVID-19 precautions as defined by the study team
- •Having completed a COVID-19 vaccination with an FDA-approved COVID-19 vaccine at least two weeks before the first study admission, and willing to provide a copy of the COVID-19 vaccination card
排除标准
- •Hemoglobin A1c <5% or >10% if measured at screening or available from historical medical report performed within the last 6 months; in absence of a valid HbA1c measurement, average blood glucose estimated from CGM data to be approximately between 100 and 240 mg/dL
- •History of diabetic ketoacidosis (DKA) in the 6 months prior to enrollment
- •Severe hypoglycemia resulting in seizure or loss of consciousness in the 6 months prior to enrollment
- •Pregnancy or intent to become pregnant during the trial
- •Currently breastfeeding or planning to breastfeed
- •Currently being treated for a seizure disorder
- •Planned surgery during study duration
- •History of cardiac arrhythmia (except for benign premature atrial contractions and benign premature ventricular contractions which are permitted)
- •Treatment with any non-insulin glucose-lowering agent (metformin, GLP-1 agonists, pramlintide, DPP-4 inhibitors, SGLT-2 inhibitors, biguanides, sulfonylureas and naturaceuticals)
- •A known medical condition that in the judgment of the investigator might interfere with the completion of the protocol.
- •Use of an insulin delivery mechanism that is not downloadable by the participant or study team
- •Known contact with COVID-positive individual within 14 days of any study admission without negative follow-up COVID-19 Polymerase Chain Reaction (PCR) test performed 3-5 days after the date of exposure
- •Symptoms of COVID-19 (e.g., fever, shortness of breath, unexpected loss of taste or smell) developed within 14 days of any study admission
- •A positive COVID-19 test within 14 days of any study admission or during study admission participation
- •Not being fully vaccinated at the time of the first camp admission (according to Center for Disease Control (CDC) guidelines a person is intended to be fully vaccinated after two weeks from either the second dose of the Pfizer or Moderna vaccine, or the single dose of the Johnson & Johnson vaccine)
结局指标
主要结局
Low Blood Glucose Index (LBGI)
时间窗: 4 hours (dinner postprandial period); the final metric for each intervention type is obtained as the average over two consecutive camp days (days 1-2 for the first intervention; days 3-4 for the second intervention)
LBGI computed from CGM collected in the four hours following the dinner meal. LBGI is a metric quantifying the risk for hypoglycemia (the higher the LBGI, the higher the exposure to/risk of hypoglycemia), calculated based on the following two steps: 1. Transforming each CGM reading in the time-series of length N into a hypoglycemia risk score (rL(i), i=1,...,N) by applying the following transformation: rL(i) = 10 x (1.509 x (log(CGM(i))\^1.084 - 5.381))\^2, if CGM(i) \<=112.5 mg/dL; rL(i) = 0, if CGM(i) \>112.5 mg/dL 2. Averaging the risk scores rL(i), i=1,...,N. The hypoglycemia risk score ranges from 0 for CGM readings \>112.5 mg/dL (no hypoglycemia risk) to 100 for CGM readings =20 mg/dL (maximum hypoglycemia risk); consequently, LBGI can theoretically assume values between 0 and 100 as well. Clinically relevant LBGI thresholds have been defined: 1. LBGI \<2.5: low hypoglycemia risk 2. LBGI in 2.5-5: moderate hypoglycemia risk 3. LBGI \>5: high hypoglycemia risk.
次要结局
- Percentage of Time Spent in 70-180 mg/dL(4 hour (dinner postprandial period); average over two consecutive days for each intervention type, as described for primary outcome)
- Percentage of Time Spent Below 70 mg/dL(4 hour (dinner postprandial period); average over two consecutive days for each intervention type, as described for primary outcome)
- Percentage of Time Spent Above 180 mg/dL(4 hour (dinner postprandial period); average over two consecutive days for each intervention type, as described for primary outcome)
- CGM Coefficient of Variation(4 hour (dinner postprandial period); average over two consecutive days for each intervention type, as described for primary outcome)
- Total Amount of Carbohydrate Administered as Rescue Treatments(4 hour (dinner postprandial period); average over two consecutive days for each intervention type, as described for primary outcome)
- High Blood Glucose Index (HBGI)(4 hour (dinner postprandial period); average over two consecutive days for each intervention type, as described for primary outcome)
研究者
Chiara Fabris, PhD
Assistant Professor
University of Virginia