Prediabetes: Relevancia Clinica

Pre-diabetes: Clinical Relevance and Therapeutic Approach
Richard E Pratley; Glenn Matfin
Posted: 08/28/2007; British Journal of Diabetes and Vascular Disease. 2007;7(3):120-129. © 2007 Sherborne Gibbs Ltd.
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Abstract and Introduction
Abstract
Type 2 diabetes mellitus is epidemic in most developed and many developing countries. The associatedmorbidity, mortality and high costs of care, make type 2 diabetes an important global public health challenge and target for prevention. Patients at high risk for type 2 diabetes can be diagnosed by fasting glucose levels or responses to an oral glucose tolerance test (OGTT). Such patients are also at increased risk for cardiovascular disease (CVD). Since obesity and physical inactivity areimportant risk factors for type 2 diabetes, lifestyle interventions, emphasising modest weight loss and increases in physical activity, should be recommended for most patients with pre-diabetes. Such interventions are safe and effective and also reduce risk factors for CVD. Several oral antidiabetic agents have been shown to be effective at delaying onset of type 2 diabetes. Thiazolidinediones (TZDs)reduced incident diabetes by ~60%, whilst metformin, acarbose and orlistat are only about half as effective as the TZDs. Pharmacological interventions may be appropriate for patients at particular risk for developing diabetes, but the benefits of treatment need to be balanced against the safety and tolerability of the intervention. If pharmacological treatment is warranted, metformin should beconsidered first because of its favourable overall safety, tolerability, efficacy, and cost profile.
Introduction
An epidemic of diabetes threatens the health of large numbers of individuals in developed and developing countries alike.[1] Globally, the number of people with diabetes is expected to almost double in the next two decades, increasing from 194 million in 2003 to 380 million in 2025.[2]Diabetes is associated with serious micro- and macrovascular complications.[3] In particular, it is a potent risk factor for CVD and this complication accounts for much of the excess morbidity, mortality and costs of care associated with diabetes. Thus, diabetes represents a critical public health challenge and an important target for prevention efforts.
Most of the recent growth in the prevalenceof diabetes can be attributed to increases in type 2 diabetes, which now accounts for ~95% of all cases.[2] Although it is clear that a genetic predisposition contributes to type 2 diabetes, the epidemic of diabetes has largely been driven by societal and environmental changes that promote physical inactivity and obesity.[4] The pathophysiology of type 2 diabetes has been well studied in recentyears and is similar in most populations.[5-7] Insulin resistance and impaired insulin secretion are key features, preceding and predicting the development of type 2 diabetes.[5-7] Progression to overt diabetes from a pre-diabetic state occurs gradually over a period of many years and is characterised by worsening insulin resistance and insulin secretory dysfunction and gradual increases in fastingand prandial plasma glucose concentrations.[6,7] The increases in plasma glucose allow individuals at high risk for type 2 diabetes to be easily identified using widely available clinical measures.
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Definition of Pre-Diabetes
In the USA normal glucose tolerance is defined as a FPG < 5.6 mmol/L and 2 h PG in response to a 75 g OGTT of < 7.8mmol/L.[8] Diabetes is defined as a FPG ≥ 7.0 mmol/L or a 2 h PG ≥ 11.1 mmol/L during an OGTT. Pre-diabetes is an intermediate state of altered glucose metabolism with a heightened risk of developing type 2 diabetes and other associated complications. Two different categories of pre-diabetes are currently used. IFG is defined by a FPG ≥ 5.6 mmol/L but < 7.0 mmol/L. IGT is defined by a FPG...