ADDITION 20 Year Follow Up
Research type
Research Study
Full title
ADDITION UK: Register-based passive 20-year follow-up of Cambridge and Leicester participants
IRAS ID
282137
Contact name
Simon Griffin
Contact email
Sponsor organisation
University of Cambridge
Clinicaltrials.gov Identifier
ISRCTN86769081, International Standard Randomised Controlled Trial Number (ISRCTN):; NCT00237549, ClinicalTrials.gov Identifier (NCT number):
Duration of Study in the UK
0 years, 5 months, 31 days
Research summary
This application is for the 20-year follow-up of the ADDITION and ADDITION Plus Trials. The 20-year follow-up aims to collect information on cardiovascular events and risk factors, treatment, and mortality for participants of the original ADDITION and ADDITION Plus Trials. This will allow us to assess the long-term effects of the differences in treatment during the first twenty years after diagnosis. We also plan to include all data and samples collected for the ADDITION studies (as listed in A5-2) within this application, ensuring everything is consolidated under one submission, as advised by CAG.
The original ADDITION UK participants (from Cambridge and Leicester) were recruited following screening for type 2 diabetes and were allocated to either given routine care or intensive management of their diabetes. A further cohort (ADDITION Plus) was recruited (half from the original ADDITION study, half from general practices in/near Cambridge )and randomly allocated to receive intensive treatment of their cardiovascular risk factors alone or in conjunction with an individually facilitated behaviour change programme.
Results from the original ADDITION Trial demonstrated that, compared to routine care, an intervention to promote intensive management of patients with diabetes detected by screening was associated with significant differences in prescribed treatment and levels of cardiovascular risk factors at five years. These differences were associated with a 17% reduction in risk of cardiovascular events that was not statistically significant, in other words it may have been due to chance.
The lower than expected event rate among screen-detected patients and the apparent divergence of event rates between groups suggest that further follow-up of this cohort is justified to establish whether early treatment reduces long-term cardiovascular risk. Resolving this uncertainty is important in assessing the costs and benefits of screening for diabetes, and for informing early treatment decisions.
REC name
East of England - Cambridge South Research Ethics Committee
REC reference
25/EE/0253
Date of REC Opinion
3 Dec 2025
REC opinion
Favourable Opinion