The metabolic syndrome is a condition characterized by hyperinsulinemia, hypertension, visceral obesity, dyslipidemia, and glucose intolerance, which leads to increased risk of coronary-artery disease and type 2 diabetes. The National Health and Nutrition Examination Survey (NHANES III) indicated that 45 percent of the U.S. population over age 50 has metabolic syndrome, and, because of the increase in the prevalence of obesity, the incidence of the metabolic syndrome has increased by 60 percent over the last decade.
Obesity is generally accompanied by insulin resistance, which is manifest as fasting hyperinsulinemia. In addition, an elevated area under the curve for insulin values during an oral glucose-tolerance test is usual for insulin-resistant, obese individuals, and glucose utilization is markedly depressed in euglycemic insulin-clamp studies.58,59 Stimulation of glucose transport by insulin is markedly blunted in muscle of obese individuals.273459'82 This observation likely explains the decreased in vivo glucose disposal observed in insulin-resistant individuals, because muscle is the primary tissue for glucose disposal, and glucose transport into muscle is the rate-limiting step for glucose utilization.33, 35 86 88
Was this article helpful?