Determining minimally invasive alternatives to glucose, proinsulin and C-peptide in early-stage type 1 diabetes
Type 1 diabetes
49 children with two or more diabetes autoantibodies and aged <18 years of age, will be invited to take part. They will be identified from research established research monitoring programmes where they are already taking part in venous OGTTs. To ensure we have a spread of glucose values, we will aim to recruit approximately equal numbers of participants in stages 1 and 2 T1D i.e. those with 2 or more IAbs but who have normal glucose levels (stage 1) or slightly abnormal glucose levels (stage 2). To aid in recruitment stratification, we will use a recent HbA1c or OGTT (within the previous 6 months), where available, to aid categorisation of glycaemia. An effort will also be made to recruit participants across a range of ages. This study involves two visits to the hospital or research centre for OGTTs no more than 3 weeks apart, each visit should take around 3 hours. Before each visit the participant will need to fast for at least 8 hours (this would be when they are sleeping, and they can still drink water). Study Visit 1: 1. Baseline information including date of birth, gender and ethnicity will be collected as well as height and weight. 2. A cannula will be inserted to collect blood samples. Two blood samples will be taken from the cannula at the start of the test, to measure glucose, proinsulin and C-peptide. At the same time, a fingerprick blood sample (one drop) will be collected. This drop will go onto panel A of the GTT@home kit which is being provided by Digostics Ltd for the study, and measures glucose. A second one or two drops of blood will be collected using a device called ‘the Mitra’. This absorbs blood with a sponge and stores it inside the device. This sample will be analysed later to measure the proteins proinsulin and C-peptide. If it is difficult to get a second drop of blood we can skip this test. 1. The participant will drink a sugary drink, which has been measured out by the study team based on their weight, within 10 minutes. 2. 2 hours late
1. Willing and able to give informed consent for participation, or assent with parental consent 2. Aged <18 years old 3. Able to consume oral glucose drink within 10 minutes 4. Presence of diabetes autoimmunity (>=2 islet antibodies)
1. On insulin treatment for diabetes 2. On any medication that may interfere with glucose metabolism (including but not limited to steroids)