Algorithm to Control Postprandial, Post Exercise and Night Glucose Excursions in a Portable Closed Loop Format

J.H. DeVries16 enrolled

Overview

In previous studies, we tested the feasibility of a bi-hormonal closed loop system. This system for automated control of blood glucose in patients with type 1 diabetes was tested in the clinical research center as well as at the home of the patients. Glucose control with automated closed loop control was comparable to patient-managed open loop control. The closed loop system has been further developed and miniaturized (from backpack to smartphone size) in order to interfere as little as possible with daily patient life. The aim of this trial is to assess the efficacy of the new prototype at the home of the patient. It is hypothesized that the closed loop system provides better glucose control than standard open loop therapy.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Enrollment

Conditions

Diabetes Mellitus, Type 1

Interventions

Eligibility

Sex: ALLMin age: 18 YearsMax age: 75 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Diagnosed with diabetes mellitus type 1 * Treated with insulin pump therapy for a minimum of 6 months * Age between 18 and 75 years * Willing and able to sign informed consent Exclusion Criteria: * Impaired awareness of hypoglycemia (score ≥ 4) according to Gold and/or Clarke questionnaire * BMI \> 35 kg/m2 * HbA1c \> 97 mmol/mol (=11.0 %) * Use of heparin, coumarin derivatives or oral corticosteroids * Skin condition prohibiting needle insertion * Pregnancy and/or breastfeeding * Living alone during the closed loop period (the patient may ask someone to stay over temporarily) * Any condition that the local investigator feels would have interfere with trial participation or the evaluation of the results

Locations (2)

Rijnstate Hospital

Arnhem, Gelderland, Netherlands

Academic Medical Center

Amsterdam, North Holland, Netherlands

Outcomes

Primary Outcomes

Mean sensor glucose concentration

Time frame: Day 2-4

Secondary Outcomes

Proportion of time spent in each glycemic category

Glycemic categories: * Low glucose (\<3.9 mmol/l and ≥ 3.3 mmol/l) * Very low glucose (\<3.3 mmol/l and ≥ 2.8 mmol/l) * Dangerously low glucose (\<2.8 mmol/l) * High glucose (\> 10 mmol/l and ≤ 13.9 mmol/l) * Very high glucose (\> 13.9 mmol/l and ≤ 22.2 mmol/) * Dangerously high glucose (\> 22.2 mmol/l)

Time frame: Day 2-4

Number of events in each glycemic category

Time frame: Day 2-4

Number of carbohydrate-treated hypoglycemic events

Time frame: Day 2-4

Proportion of time spent in euglycemia (≥ 3.9 mmol/l and ≤ 10 mmol/l)

Time frame: Day 2-4

Glycemic variability

Calculated as Interquartile Range (IQR)

Time frame: Day 2-4

Mean sensor glucose concentration during specific periods

Periods: * Day * Night * Postprandial

Time frame: Day 2-4

Mean absolute relative difference between sensor values and self-monitored blood glucose values

Time frame: Day 2-4

Heart rate

Time frame: Day 2-4

Physical activity

Acceleration measured with a tri-axial accelerometer. The physical activity parameter is calculated as the magnitude of the total acceleration vector (square root of the sum of the squared axes).

Time frame: Day 2-4

Mean glucose concentration per day

Intervention arm (closed loop) only

Time frame: Day 1-4

Time that the control algorithm is inactive

Intervention arm (closed loop) only

Time frame: Day 1-4