T1DRA (Type 1 Diabetes Risk in Adults)

The half of T1D that gets forgotten

Type 1 diabetes (T1D) is still widely thought of as a childhood disease. It is not. About half of all T1D diagnoses are made in adults.¹ Yet look at the screening programmes that exist — Germany's Fr1da, the UK's ELSA, Italy's national law, Colorado's ASK — and almost all of them screen children, or screen relatives of people who already have T1D. The adult who will be diagnosed at 34, with no family history, is invisible to nearly all of it.

That gap has a cost. Adults are not spared the crisis that screening is meant to prevent: diabetic ketoacidosis (DKA) rates of up to 24% are estimated in adults with new-onset T1D in Europe.¹ Adults are also more likely to be misdiagnosed as having type 2 diabetes first, and to be treated for months or years with the wrong drugs.

T1DRA (Type 1 Diabetes Risk in Adults) is the study built for exactly this blind spot.

What T1DRA is

T1DRA is run by the University of Bristol, led by Professor Kathleen Gillespie, and funded by The Helmsley Charitable Trust with Diabetes UK.²³ It aims to recruit 20,000 UK adults aged 18 to 70 from the general population — you do not need a relative with T1D to take part.²³ Recruitment opened in November 2023 and is ongoing.

Diabetes UK's framing is the accurate one: it makes the UK the first country in the world to offer T1D screening for both children and adults in the general population — in a research setting.³ That qualifier matters, and we keep it. This is a study, not a service.

The test

It is about as low-friction as screening gets:²

• A free at-home kit arrives in the post.
• You take a finger-prick blood sample yourself — no clinic visit, no venous blood draw.
• You return it in prepaid packaging.
• Results take 8-10 weeks.

The lab looks for islet autoantibodies — the immune markers that show the attack on insulin-producing cells has already begun, often years before any symptom. Two or more autoantibodies is the definition of presymptomatic T1D: stage 1 (autoantibodies, normal glucose), stage 2 (autoantibodies plus abnormal glucose), stage 3 (clinical diabetes).

Why the prediction is weaker in adults — and why that is the point

Here is the honest part, and it is the most important thing on this page.

The autoantibody staging model was built and validated mostly in children. Applying it to adults is not a straightforward copy-paste:

• Autoantibody prevalence is lower in the adult general population.
• Single-antibody positivity is commoner — frequently GAD-only — and a single antibody carries far lower risk of progression than two or more.
• Progression rates in adults are not well characterised. Nobody can currently tell a 45-year-old with two autoantibodies what their five-year risk actually is with the confidence a paediatrician could offer a child's family.

So T1DRA's predictive value is provisional by design — which is precisely why we score it well below the paediatric programmes. But that is not a flaw in the study; it is the study. T1DRA is a natural-history study: its central job is to produce the missing numbers — how common islet autoantibodies really are in adults, and how quickly adults with them progress. No existing screening service is generating that data. That, and not novelty, is T1DRA's defensible distinction.

What a positive result unlocks

Two things, both real.

Monitoring. Knowing in advance is what turns a T1D diagnosis from an emergency into an appointment. It is the main defence against DKA — the crisis that still accounts for up to a quarter of adult-onset presentations.¹

Access to a disease-modifying drug. Teplizumab is the first therapy shown to delay clinical T1D. NICE recommended it for NHS use in stage 2 T1D for people aged 8 and over — adults included — in final draft guidance on 23 June 2026, since confirmed in final guidance (TA1176).⁴ But a drug for stage 2 is useless if nobody knows they are in stage 2. NICE spells out the bottleneck: people are likely to learn they have stage 2 T1D in one of three ways — by taking part in a research study, by being tested because a family member has T1D, or by being tested incidentally for some other reason.⁴ T1DRA is an example of that first route for adults, as ELSA is for children. For a UK adult with no family history and no reason to be tested, a study like T1DRA is realistically the only door.

That is a strange state of affairs worth naming plainly: screening is the rate-limiting step for the drug, not the other way round.

Honest limits

• It is a study, not a service. Fixed recruitment target, finite funding, an end date. When it closes, the adult screening pathway it provides closes with it unless something replaces it.
• We quote no enrolment figure. The study reports only that thousands have joined; no verified participant count and no results paper are published. We will not invent precision that does not exist.
• No published outcomes yet. T1DRA has not yet reported prevalence, progression or DKA-reduction results. Our evidence: moderate rating reflects a well-designed, well-funded study that has not yet produced its data.
• Adults elsewhere are not entirely without options. T1Detect in the US is open to the general public of all ages, so it is not true that adults can only be screened in the UK. What is true is that no country offers adults a routine, funded screening pathway, and no other programme is set up to answer the natural-history questions T1DRA is asking.
• A positive result is not a diagnosis. It is a risk finding, and — for now — one whose adult timescale is genuinely uncertain. Counselling and follow-up matter enormously here, and honest uncertainty must be part of what is communicated.

Why we rank it where we do

T1DRA scores lower than ELSA or Fr1da on predictive value and access, and that is not a criticism — it is the difference between working in a well-mapped population and working in an unmapped one. The paediatric programmes are harvesting a validated model. T1DRA is building the model for a population that has been left out of it, and it is doing so with the lowest-burden test in the field: one finger-prick, done at home, posted back for free.

If half of T1D starts in adulthood, then half of the case for screening does too. T1DRA is the only serious attempt anywhere to prove it.

References

1. An international consensus on screening and monitoring early-stage type 1 diabetes: a roadmap to European implementation. Diabetes, Obesity and Metabolism (2026). https://doi.org/10.1111/dom.70569 ↩ ↩² ↩³

2. T1DRA — Type 1 Diabetes Risk in Adults. University of Bristol (official study site, accessed 2026). https://t1dra.bristol.ac.uk/ ↩ ↩² ↩³

3. Diabetes UK. World-first study to screen adults for type 1 diabetes opens for recruitment. diabetes.org.uk. https://www.diabetes.org.uk/about-us/news-and-views/world-first-study-screen-adults-type-1-diabetes-opens-recruitment ↩ ↩² ↩³

4. NICE. First disease-modifying therapy for NHS use to delay the onset of type 1 diabetes recommended. nice.org.uk (23 June 2026). https://www.nice.org.uk/news/articles/teplizumab-to-delay-the-onset-of-type-1-diabetes-recommended ↩ ↩²