Inhibition of postprandial hyperglycemia by acarbose is a promising therapeutic strategy for the treatment of patients with the metabolic syndrome

The metabolic syndrome is strongly associated with insulin resistance and has been recognized as a cluster of risk factors for cardiovascular diseases such as viscera[ obesity, hypertension, diabetes, and atherogenic dyslipidemia. Recently, insulin resistance in the absence of overt diabetes or the metabolic syndrome itself has been associated with endothelial dysfunction, one of the initial steps in the process of atherosclerosis. Postprandial hyperglycemia, one of the characteristic features of insulin resistance, induces oxidative stress generation and elicits vascular inflammation and platelet activation, thus being involved in the pathogenesis of atherosclerosis. A recent multicenter, placebo-controlled randomized trial, STOP-NIDDM trial, revealed that acarbose (Glucobay(R)), an a-glucosidase inhibitor, improved postprandial hyperglycemia and subsequently reduced the risk of development of type 2 diabetes in patients with impaired glucose tolerance (IGT). In this study, acarbose treatment was also found to stow the progression of intima-media thickness of the carotid arteries, a surrogate marker for atherosclerosis, and to reduce the incidence of cardiovascular diseases and newly diagnosed hypertension in subjects with IGT. Acarbose significantly reduced body mass index and waist circumference in these patients over 3 years. Furthermore, a metaanalysis of seven long-term studies has also shown that intervention with acarbose prevents myocardial infarction and cardiovascular diseases in type 2 diabetic patients. In this analysis, glycemic control, triglyceride levels, body weight and systolic blood pressure was also significantly improved during acarbose treatment. These observations suggest that prevention of postprandial hyperglycemia by acarbose may be a promising therapeutic strategy for reducing the increased risk for diabetes, hypertension, dyslipidemia, obesity, and cardiovascular diseases in patients with the metabolic syndrome. Acarbose improves postprandial hyperglycemia by delaying the release of glucose from complex carbohydrates in the absence of an increase in insulin secretion. Therefore, we would like to hypothesize here that this improvement in glucose metabolism could be associated with amelioration in insulin sensitivity, thus explaining the above-mentioned beneficial cardiometabolic actions of acarbose. Large clinical trials will provide us with more definite information whether acarbose treatment can improve insulin sensitivity and resuttantly reduce the risk of diabetes, hypertension and cardiovascular diseases in patients with the metabolic syndrome. (c) 2005 Elsevier Ltd. All rights reserved.