Advanced Bolus Calculator for Type 1 Diabetes (ABC4D)

Imperial College London

Status

Completed

Conditions

Type 1 Diabetes

Treatments

Device: ABC4D

Device: Standard bolus calculator

Study type

Interventional

Funder types

Other

Identifiers

NCT02053051

13SM0091

Details and patient eligibility

About

This study aims to assess the safety and efficacy of a novel advanced bolus calculator in subjects with Type 1 diabetes. Insulin bolus calculators have been developed to aid insulin dose adjustment and existing standard insulin bolus calculator consist of a simple algorithm that requires five subject-specific parameters as input to generate a recommended bolus insulin dose:

current blood glucose (mmol/L)
target blood glucose (mmol/L)
insulin-to-carbohydrate ratio (grams of carbohydrate per 1 unit of insulin)
total grams of carbohydrate in meals
insulin sensitivity factor (reduction in glucose per 1 unit of insulin)

Full description

The Diabetes Technology team at Imperial College have developed a novel advanced bolus calculator. The complete integrated system consists of a commercially available smartphone that holds the novel advanced algorithm. The system requires regular updates of cases derived from retrospective blinded continuous glucose monitoring data and for this a commercially available glucose sensor will be used. Each new case includes information about the problem (e.g. capillary blood glucose, meal information and physical exercise), solution (recommended insulin dose) and outcome (blood glucose following a meal). The novel decision support algorithm is based on case-based reasoning (CBR). CBR is an artificial intelligence technique that tries to solve newly encountered problems by applying the solutions learned from solved problems encountered in the past.

The end-product is therefore a subject specific insulin bolus calculator that continues to improve with time. The project utilises commercially available glucose sensors and smartphones (iPhone), integrated with a novel algorithm for insulin bolus calculation. The aim of the ABC4D is to minimise high and low glucose excursions which are associated with the complications of diabetes including blindness, kidney failure, nerve damage and cardiovascular disease.

An interim analysis was conducted in Phase 4 after 25 participants completed the study (in line with the protocol) and it was agreed to stop the study at this stage. A further protocol amendment was approved by REC/MHRA to commence ABC4D phase 5 (different CT.gov number: NCT03963219).

Enrollment

25 patients

Sex

All

Ages

18+ years old

Volunteers

No Healthy Volunteers

Inclusion criteria

Adults ≥18 years of age
Diagnosis of T1DM for > 1 year
On MDI using a basal-bolus insulin regime
Structured education in previous 3 years
HbA1c ≤ 86mmol/mol
No severe hypoglycaemia (defined as needing 3rd party assistance) in previous year

Exclusion criteria