An observational study in Diabetes (Insulin-requiring, Type 1 or Type 2), Diabetes and Diabetes (DM), sponsored by Royal Devon and Exeter NHS Foundation Trust. Recruiting at 4 sites in United Kingdom. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-18.
Sponsored by Royal Devon and Exeter NHS Foundation Trust · Observational
The purpose of this research is to understand the impact of retained endogenous insulin (as measured by C-peptide) on quality of life and related outcomes in people living with insulin treated diabetes, and, in those living with type 1 diabetes, to determine the pragmatic and non-pragmatic C-peptide measures which have the strongest association with clinical benefit (including repeated home samples and derived measures of beta cell function). The investigators will do this in two ways:
Firstly, the investigators will extend a large existing prospective study of new adult onset diabetes (Getting the Right Classification and Treatment From Diagnosis in Adults With Diabetes (StartRight)) https://clinicaltrials.gov/ct2/show/NCT03737799) which has followed 1800 participants for median 4 years from diabetes diagnosis. Participants with insulin treated diabetes will be invited to take part in a further research visit remotely or face to face. The investigators will assess the longitudinal relationship between C-peptide and the available quality of life, mental health status and healthcare utilisation measures over up to 9 years from diabetes diagnosis and assess additional measures in cross sectional analysis.
In the second part of this research, the investigators will utilise cohorts of over 2500 participants with type 1 diabetes, measured C-peptide and consent to recontact to recruit 200 participants with a range of C-peptide. Eligible participants with C-peptide measured in clinical care may also be invited to take part. The investigators will undertake detailed assessment of complex and pragmatic measures of C-peptide and beta cell function and compare performance in predicting glycaemic outcomes (using data from continuous glucose monitors) and (where relevant) patient reported outcomes.
The purpose of this study is to understand the possible benefits of restoring insulin secretion in people living with diabetes, and to understand how insulin secretion can be best measured in people living with diabetes.
Most people living with type 1 diabetes stop making their own insulin, this means that insulin injections are needed to survive. It also means their blood glucose is variable, meaning it is very difficult to control blood glucose levels. This is in contrast to type 2 diabetes, where most people keep making their own insulin, and loss of insulin production is uncommon.
Previous research has shown that some people with type 1 diabetes keep making some of their own insulin, and this can be very helpful for their blood glucose control. However, there is limited information on long term benefits of making insulin, and other possible benefits, such as on wellbeing, have not been studied. It is important that the full benefits of making insulin are known as new treatments have been developed to preserve insulin secretion in type 1 diabetes, and/or to restore insulin secretion. These treatments are expensive and can have side effects, and have been studied only in small studies for a short amount of time. It is important to fully understand the likely long-term benefits of preserving or restoring insulin secretion to know whether healthcare providers like the NHS should fund these treatments.
At present research studies that are testing new treatments to preserve or restore a person's insulin production need to frequently test insulin secretion, using a test called a mixed meal tolerance test that needs to be undertaken in a hospital setting and takes at least 2.5 hours. This makes these studies difficult to take part in, and expensive to run. Insulin production can now be measured at home, on a finger-prick test, but more information is needed on the best way to do the home test for these kinds of studies.
This research has two parts. In the first part of this research the investigators will measure insulin secretion (using a test called C-peptide) in 500 people with insulin treated diabetes who have already taken part in a large recent study that measured their insulin secretion, and other important measures such as their quality of life and use of healthcare services, every year for up to 4 years after diabetes diagnosis. There will be assessment of participants' quality of life and other measures related to diabetes. The investigators will use this information, and the information already collected in the study, to understand the effects of retaining or loosing insulin production over up to 9 years from diabetes diagnosis, and compare whether this differs in type 1 and 2 diabetes.
In the second part of this research the investigators will recruit 200 participants with type 1 diabetes who have had their insulin secretion measured in part one of this research, in other research or in clinical care. Information from this previous testing will be used to ensure participants are recruited with a range of insulin production. Participants will attend a research facility for assessment of their insulin production over 2 hours after a liquid meal similar to a milkshake. Participants will then undertake this test at home, using finger-prick samples after the same liquid meal, and after 3 of their own normal meals. Participants will also monitor their glucose over 2 weeks using a device called a continuous glucose monitor. This information will be used to understand if home measures are as accurate as the test in the research facility, and work as well in predicting a person's risk of low glucose (hypoglycaemia) and how variable their glucose is.
The end result of this research will be important information to inform the design of studies of new treatments to preserve or restore insulin secretion for people living with diabetes and understand the likely long-term benefits of these treatments.
3,754 studies on the registry are indexed under Diabetes Mellitus, Type 1; 600 are open to participants now.
This study's planned enrollment of 700 is above the median of 125 across 792 observational studies indexed under Diabetes Mellitus, Type 1.
Browse Diabetes Mellitus, Type 1 studies →Royal Devon and Exeter NHS Foundation Trust is the lead sponsor of 63 studies on the registry; 9 are open to participants now.
Compared within Diabetes Mellitus, Type 1, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Diabetes Mellitus. The counts are of registry records indexed under each term, refreshed daily. How we classify →
ARM 1: Participants who have previously taken part in the StartRight study (NCT03737799) with consent to re-contact for future research (from sites across the United Kingdom (UK)).
ARM 2: Participants who have previously taken part in the StartRight study or other diabetes research cohorts, as well as patients referred by their clinician or self-referred (across the UK).
ARM 1
Inclusion Criteria:
ARM 2
Inclusion Criteria:
Exclusion Criteria:
- Renal failure defined by \<30mL/min/1.73 m²
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Adults (aged \>= 18 years) diagnosed with diabetes for \>3 years, treatment with insulin, and previously taken part in the StartRight study with consent to re-contact.
Other: Observational
Adults (aged \>= 18 years) diagnosed with type 1 diabetes. Known level of insulin secretion, measured using a C-peptide test after diabetes diagnosis. Participants will have had C-peptide measured as part of a previous research study or as part of their diabetes clinical care. Where C-peptide is not measured, participant must be within 7 years of diagnosis and have at least 1 positive islet antibody, measured at any time since diabetes diagnosis.
Other: Observational
Observational
Capillary C-peptide measured 1-5 hours after a meal containing carbohydrates (Arm 1)
Analysis of Arm 1 will assess the relationship between home post-meal C-peptide (measured serially from within 12 months of diagnosis up to 10 years post-diagnosis, through extension of an existing study), and the secondary outcomes listed below. This will be assessed as longitudinal change over time (Arm 1 cohort) and cross-sectionally using the most recent visit data from the combined Arm 1 and Arm 2 cohorts.
Time frame: 1 day during study participation
Plasma and capillary C-peptide (Arm 2)
Primary analysis for Arm 2 will assess the relationship between home capillary C-peptide measurements (post-meal, assessed individually \& as the average of up to three measurements, and 90-minute post-mixed meal tolerance test) and 90-minute plasma C-peptide measured during a mixed meal tolerance test conducted at a research centre. Secondary analysis will compare the relationship between C-peptide measures and the continuous glucose monitoring secondary outcome listed below.
Time frame: 90-minutes post baseline
Questionnaire assessed hypoglycaemia and hypoglycaemia unawareness (Arm 1 & Arm 2)
Results from analysis of data from Modified Clarke/Edinburgh Hypoglycaemia History questionnaire
Time frame: Symptoms experienced during 4 weeks prior to study enrolment
Questionnaire assessed emotional burden (Arm 1 & Arm 2)
Results from analysis of data from Diabetes Distress Scale questionnaire
Time frame: Symptoms experienced during 4 weeks prior to study enrolment
Questionnaire assessed quality of life/wellbeing (Arm 1 & Arm 2)
Results from analysis of data from Veterans RAND 12-Item Health Survey (VR-12) questionnaire
Time frame: Symptoms experienced during 4 weeks prior to study enrolment
Changes/updates to diabetes treatment, complications and healthcare utilisation for relevant medical conditions since previous study visit (Arm 1)
Data collected during current study visit combined with data from previous study visit.
Time frame: Up to 3 years prior to study enrolment
Continuous glucose monitor measured glucose variability and hypoglycaemia (Arm 2)
Analysis for Arm 2 will compare the relationship of different C-peptide measures to glucose variability (assessed as Standard Deviation glucose) and hypoglycaemia (assessed as % time glucose below 3mmol/L), derived from 14 days of continuous interstitial glucose monitoring
Time frame: 14 days during study participation
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Royal Devon and Exeter NHS Foundation Trust