Prediabetes and the risk of diabetes

We agree with Adam Tabák and colleagues1Tabák AG Herder C Rathmann W Brunner EJ Kivimäki M Prediabetes: a high-risk state for diabetes development.Lancet. 2012; 379: 2279-2290Summary Full Text Full Text PDF PubMed Scopus (1721) Google Scholar that prediabetes is a risk factor for diabetes. Because diabetes is a risk factor for cardiovascular events,2Roy B Pawar PP Desai RV et al.A propensity-matched study of the association of diabetes mellitus with incident heart failure and mortality among community-dwelling older adults.Am J Cardiol. 2011; 108: 1747-1753Summary Full Text Full Text PDF PubMed Scopus (10) Google Scholar it is tempting to conclude that prediabetes is also a risk factor for cardiovascular events. However, we have shown that, in community-dwelling older adults in the Cardiovascular Health Study,3Deedwania PC Ahmed MI Mujib M Ahmed A Is prediabetes associated with increased mortality and cardiovascular morbidity in community-dwelling older adults?.J Am Coll Cardiol. 2010; 55: A137Summary Full Text Full Text PDF Scopus (1) Google Scholar prediabetes had no independent association with increased risk of mortality or incident cardiovascular events, including heart failure. A potential explanation for this observation is that older adults with incident diabetes might die from other competing risk factors before development of diabetes-related complications. It might also explain why lifestyle and drug-based interventions in those with prediabetes do not seem to reduce the risk of mortality or cardiovascular events despite reduction in the risk of incident diabetes.4Hopper I Billah B Skiba M Krum H Prevention of diabetes and reduction in major cardiovascular events in studies of subjects with prediabetes: meta-analysis of randomised controlled clinical trials.Eur J Cardiovasc Prev Rehabil. 2011; 18: 813-823Crossref PubMed Scopus (118) Google Scholar This point is important because the prevalence of prediabetes increases with age and nearly half of older adults in the USA have prediabetes.5Cowie CC Rust KF Ford ES et al.Full accounting of diabetes and pre-diabetes in the US population in 1988–1994 and 2005–2006.Diabetes Care. 2009; 32: 287-294Crossref PubMed Scopus (959) Google Scholar These findings question the wisdom of routine screening for prediabetes in community-dwelling older adults for targeted interventions to prevent incident cardiovascular events and death in those with prediabetes. We declare that we have no conflicts of interest. Prediabetes and the risk of diabetes – Authors' replyArnaud Chiolero and Fred Paccaud note that prediabetes is not a unique disease entity and that the risk of diabetes is a continuum along blood glucose values. This comment highlights one important message of our paper—ie, the potential benefits of risk scores for diabetes risk prediction. In addition to blood glucose as a continuous risk factor for diabetes, risk prediction algorithms take into account other important modifiable risk factors such as hypertension, diet, or physical inactivity. There is, however, a need for further research because few studies have examined whether the use of risk calculators improves prediction of diabetes risk on the basis of current definitions of prediabetes. Full-Text PDF