European Primary Care Cardiovascular Society

Training GPs to treat screen-detected diabetes intensively also benefitted normoglycemic individuals

Simmons RK, Diabetologia, 2017

Does training of general practitioners for intensive treatment of people with screen-detected diabetes have a spillover effect on mortality and cardiovascular morbidity in ‘at risk’ individuals with normoglycaemia? Results from the ADDITION-Denmark cluster-randomised controlled trial

Simmons RK, Bruun NH, Witte DR, et al.
Diabetologia 2017;60:1016-1021


In contrast to clear guidelines for treatment of diabetes, no treatment protocols are known in most countries for those who are positive based on a diabetes risk questionnaire, but normoglycaemic on biochemical testing.
The Anglo–Danish–Dutch Study of Intensive Treatment In People with Screen-Detected Diabetes in Primary Care (ADDITION)-Denmark trial [1], in which 175 general practices were cluster-randomized to routine care or to receive training and support for the implementation of an intensive treatment program for individuals with screen-detected diabetes, intervention was associated with a non-significant risk reduction in cardiovascular disease events, during a 5-years follow-up [2].
In this current analysis of the ADDITION-Denmark (screening 2001-2006), it was investigated whether the education and guidelines that were offered had also an impact on the management of patients with normal blood glucose levels following screening, in order to assess the potential spillover effect of the intervention. Participants diagnosed with type 2 diabetes were managed according to the treatment regimen to which their practice had been allocated: routine care (control) or intensive treatment. For intensive treatment, general practitioners and nurses received training and support via small group or practice-based educational meetings where treatment targets/algorithms, lifestyle advice and supporting evidence were discussed. Cardiovascular risk was determined based on heart SCORE, which was assessed if participants score ≥5 points on the questionnaire.

Main results

  • 21,513 participants screened positive for diabetes based on a questionnaire, were found to have normal blood glucose; 10,289 in the routine care (control) group and 11,224 in the intensive treatment group.
  • In the intensive treatment group, 1904 (17.0%) cardiovascular disease events occurred during a median follow-up of 8.9 years, which was higher (1880, 18.3%) in the control group (HR 0.92, 95% CI 0.85-0.99). This was more pronounced in those with a heart SCORE ≥10 (HR 0.85, 95% CI 0.75-0.96).
  • Deaths in the intensive and control treatment groups were 8.2% and 8.0%, respectively, of which 13.5% and 12.8% were cardiovascular disease-related.
  • HR for all-cause mortality was 1.02 (95% CI 0.92-1.14) across all levels of cardiovascular disease risk.


Training of general practitioners to provide target-driven intensive management of blood glucose levels and other cardiovascular risk factors showed some evidence for a spillover effect; treating patients with screen-detected diabetes with normal glucose levels intensively reduced the number of cardiovascular events, which was clinically meaningful in those at highest cardiovascular disease risk. Therefore, it has been hypothesized that training and support of general practitioners in the intensive treatment arm of the trial may have improved the management of lifestyle behavior, and maybe medication adherence, among patients identified at high risk but without diabetes on biochemical testing.
Find this article online at Diabetologia


1. Lauritzen T, Griffin S, Borch-Johnsen K, Wareham NJ, Wolffenbuttel BH, Rutten G (2000) The ADDITION study: proposed trial of the cost-effectiveness of an intensive multifactorial intervention on morbidity and mortality among people with Type 2 diabetes detected by screening. Int J Obes Relat Metab Disord 24(Suppl 3):S6–S11
2. Griffin SJ, Borch-Johnsen K, DaviesMJ et al (2011) Effect of early intensive multifactorial therapy on 5-year cardiovascular outcomes in individuals with type 2 diabetes detected by screening
(ADDITION-Europe): a cluster-randomised trial. Lancet 378:156–167