Capillary Islet Autoantibody Testing at the Preschool Vaccination Is a Feasible and Acceptable Method to Screen Children for Type 1 Diabetes

Background: Islet autoantibody screening for type 1 diabetes (T1D) reduces life-threatening diabetic ketoacidosis, hospitalization and identifies individuals eligible for future preventative treatments. 3.5-4 years has been indicated as an optimal time to screen younger children for T1D at a single-time point. We therefore assessed the feasibility and acceptability of screening at this age, to align with the pre-school vaccination visit, in a first of its kind, proof-of-concept study in the UK. Methods: Children attending routine pre-school vaccinations (n= 63; median age 3.5y (IQR 3.4-3.6, range 3.1-5.1y), 26 (41.3%) male) provided capillary blood samples which were posted for IAA, GADA, IA-2A and ZnT8A analysis. Serum volumes >60µL were tested using Radiobinding assay (RBA), and <60µL by Luciferase Immunoprecipitation Systems (LIPS) assay. Acceptability was assessed using open question postcards, and semi structured interviews. Results: There was 97% (61/63 samples) success in sample analysis, with median serum collected 100µL (IQR 80-155) and 83% (52/63)>60µL. One participant screened and confirmed positive by RBA for IAA. Participants (n=15 interviews, n=31 postcards) were uniformly positive about screening aligning to the vaccination programme, citing that they may have been less likely to take part had screening been a separate visit. Themes identified included being prepared in the event of a T1D diagnosis, feeling reassured by a negative test result, and the long-term benefit of screening outweighing short-term upset. Parents reported that the volume of blood was higher, and collection time longer than expected. Conclusions: Capillary islet autoantibody testing is a feasible and acceptable method to screen children for T1D. Aligning sample collection to the pre-school vaccination was not a deterrent to vaccination. The approach of combining screening with a routine health visit may enable uptake and could be cost saving. Disclosure C. Scudder: None. J. Townson: None. R. Besser: Consultant; Provention Bio, Inc. J. Bowen-morris: None. P. H. Evans: None. S. C. Jones: None. N. P. B. Thomas: None. R. Fox: None. J. Todd: Advisory Panel; GlaxoSmithKline plc., Precion, Qlife, Vesalius Therapeutics. S. Greenfield: None. C. Dayan: Advisory Panel; AstraZeneca, Consultant; Provention Bio, Sanofi, Avotres Inc., Other Relationship; Dompé, Merck & Co., Inc. Funding National Institute for Health Research (203948)