Prevention of Type 2 Diabetes

As the human and economic cost of type 2 diabetes has surged, focus on its prevention has intensified. Clinical trials across the globe have demonstrated that diabetes can be prevented in high-risk populations over a wide range of cultures and ethnicities [1–12]. Further, reduction in diabetes onset is observed beyond the time of the interventions, albeit attenuated [13, 14]. Waning benefit post-intervention has been attributed to lack of long-term adherence to lifestyle changes or drug therapy. An alternate explanation, however, may be that lack of progression to diabetes rather than the restoration of normoglycemia has been our goal. All of the landmark trials for diabetes prevention to date have enrolled participants with untreated prediabetes due to their exceptionally high risk for acquiring diabetes [1–12]. Even when overt diabetes is delayed or prevented, both microand macrovascular diseases appear more prevalent in those with prediabetes compared to their normoglycemic peers [15–18]. Thus, there is reason to believe that true prevention of diabetes and its complications likely reside in the reversal of prediabetes and the restoration of normoglycemia. New evidence supports this speculation [19] and guidelines are changing accordingly [20]. Nevertheless, there is much to be considered in identifying the people at highest risk for diabetes and determining when and how to institute preventive measures. Through the combination of known and emerging risk factors, the worldwide burden of type 2 diabetes continues to rise. National statistics estimate roughly 29 million Americans – 9.3% of the population – currently have diabetes, reflecting an approximate tripling in the prevalence over the past 25 years [21]. Even more staggering are the 415 million people around the world with diabetes – a number that is expected to increase by more than 50% by 2040 [22]. And although these numbers include all diabetes, >90% have type 2. Fortunately, a number of clinical trials have demonstrated that early intervention can prevent or delay type 2 diabetes [1–12] and newer evidence has shown that prevention of diabetes can also prevent microvascular complications [13].