External National Validation of the Leicester Self-Assessment Score for Type 2 Diabetes Using Data from the English Longitudinal Study of Ageing

Aims: The Leicester Self-Assessment score is a non-invasive risk assessment that identifies individuals at risk of Non-Diabetic Hyperglycaemia or undiagnosed Type 2 Diabetes Mellitus (DM). We validated this score using a representative English dataset for detecting prevalent Non-Diabetic Hyperglycaemia or undiagnosed Type 2 DM (defined as HbA1c ≥6.0%) and for identifying those who go on to develop Type 2 DM within 10 years. Methods: Data were taken from the English Longitudinal Study of Aging, a nationally representative dataset of people aged ≥50 years. The area under the receiver operator curve (AUROC) and performance metrics for the score at the recommended cut-point (≥16), were calculated for the outcomes of HbA1c ≥6.0% (42 mmol/mol) at baseline and self-reported Type 2 DM within 10 years in those aged 50-75 years at baseline. Results: 3,203 individuals had a baseline HbA1c measurement, of whom 247 (7.7%) had HbA1c ≥6.0% (42 mmol/mol). AUROC was 69.4% (95%CI: 66.0%-72.9%) for baseline HbA1c ≥6.0%. 3,550 individuals had diabetes status recorded at 10 years, of whom 324 (9.1%) were diagnosed with Type 2 DM within this time; the AUROC for this outcome was 74.9% (95%CI: 72.4%-77.5%). The cut-point of ≥16 had a sensitivity of 89.2% (95%CI: 85.3-92.4%) and a specificity of 42.3% (95%CI: 40.5-44.0%) for Type 2 DM within 10 years. Conclusions: The Leicester Self-Assessment score is validated for use across England to identify people with Non-Diabetic Hyperglycaemia or undiagnosed Type 2 DM. Those with a high score are at high risk of developing diabetes in the future.