Glucose Response, Excursions And Treatment (GREAT) Study

• Status: Completed
• Trial end date: 2015-11-01
• Target enrollment: 0
• Participant gender: All

Summary

Patients with type 2 diabetes have very variable endogenous insulin secretion. While some patients have relatively preserved endogenous insulin with marked insulin resistance others may develop the very severe insulin deficiency seen in type 1 diabetes. The impact of this variation on hypoglycaemia risk and treatment response in type 2 diabetes is unclear. This project aims to determine the impact of residual endogenous insulin secretion on glucose variability, hypoglycaemia risk and treatment response in insulin-treated participants with a clinical diagnosis of type 2 diabetes. The investigators will recruit participants from existing cohorts known to have severe insulin deficiency despite classical clinical characteristics of type 2 diabetes. The investigators will recruit other participants with insulin-treated type 2 diabetes and retained endogenous insulin secretion matched for glycemia and gender. The investigators will assess glucose variability (using continuous glucose monitoring system (CGMS)) and treatment response to a single dose of the glucose lowering therapy vildagliptin and compare responses between groups. This study will allow us to assess the potential utility of measuring endogenous insulin secretion in insulin-treated type 2 diabetes as a marker of hypoglycaemia risk and in determining likely response to oral therapy.

• Phase: N/A
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: Royal Devon and Exeter NHS Foundation Trust
• Collaborator: NIHR Exeter Clinical Research Facility
• Treatments: Dipeptidyl-Peptidase IV Inhibitors; Insulin

Criteria

Inclusion Criteria:

Clinical diagnosis of type 2 diabetes Diagnosis of diabetes ≥ age 35 Treated with insulin Time from diagnosis to requiring insulin therapy of ≥36 months HbA1c ≥53mmol/mol (7%) and ≤100mmol/mol (11.3%)

Presence or absence of severe endogenous insulin deficiency:

• Severe deficiency = fasting blood C-peptide ≤0.08nmol/L or stimulated C-peptide ≤0.2nmol/L or post meal urine C-peptide creatinine ratio ≤0.2nmol/mmol

• Retained endogenous insulin secretion = fasting blood C-peptide ≥0.25nmol/L or stimulated C-peptide ≥0.6nmol/L or post meal urine C-peptide creatinine ratio ≥0.6nmol/mmol

Exclusion Criteria:

Pregnancy or breastfeeding Moderate renal impairment (EGFR<30 mls/min/1.73m2) Hepatic impairment (ALT >3 times upper limit of the normal range) Concurrent treatment with GLP-1 receptor analogue or DPPIV inhibitor glucose-lowering therapy.

Planned changes to glucose lowering therapy during the study duration Unable to self-monitor blood glucose Unable to give informed consent