Early outcomes from the English National Health Service diabetes prevention program

Objective: To assess weight and HbA1c changes in the Healthier You: National Health Service Diabetes Prevention Programme (NHS DPP), the largest DPP globally to achieve universal population coverage. Research Design and Methods: A service evaluation assessing intervention effectiveness for adults with non-diabetic hyperglycaemia (HbA1c 42-47 mmol/mol (6.0-6.4%)) or fasting plasma glucose 5.5-6.9 mmol/l) between programme launch in June 2016 and December 2018, using prospectively collected national service-level data in England. Results: By December 2018, 324,699 people had been referred, 152,294 had attended initial assessment and 96,442 had attended at least one of 13 group-based intervention sessions. Allowing sufficient time to elapse: 53% attended initial assessment; 36% attended at least one group-based session; and 19% completed the intervention (attended over 60% of sessions). Of the 32,665 that attended at least one intervention session and had sufficient time to finish, 17,252 (53%) completed: intention-to-treat analyses demonstrated mean weight loss 2.3 (95% CI: 2.2-2.3) kg and HbA1c reduction 1.26 (1.20-1.31) mmol/mol (0.12 (0.11-0.12) %); completer analysis demonstrated mean weight loss 3.3 (3.2-3.4) kg and HbA1c reduction 2.04 (1.96-2.12) mmol/mol (0.19 (0.18-0.19) %). Younger age, female sex, Asian and black ethnicity, lower socioeconomic status and normal baseline BMI were associated with less weight loss. Older age, female sex, black ethnicity, lower socioeconomic status and baseline overweight and obesity were associated with smaller HbA1c reduction. Conclusions: Reductions in weight and HbA1c compare favourably to those reported in recent meta-analyses of pragmatic studies and suggest likely future reductions in participant type 2 diabetes incidence.