The 1st World Congress on the Insulin Resistance Syndrome.

Abstract

This is the first of two articles covering the 1st World Congress on the Insulin Resistance Syndrome (IRS), which was held in Los Angeles, 21–22 November 2003. Yehuda Handlesman (Tarzana, CA), the conference organizer, noted that it reflects an endeavor to bring an understanding of basic science into the clinical practice of medicine. Contributory causes of insulin resistance include obesity, sedentary lifestyle, and many other characteristics and conditions. Handlesman noted that the syndrome has been assigned International Classification of Disease (ICD)-9 code 277.7 as the dysmetabolic syndrome. Many aspects of the IRS are pharmacologically treatable when lifestyle modification is ineffective, and we need tools to determine which approaches are appropriate for particular individuals. Gerald Reaven (Stanford, CA) reviewed the six- to eightfold variation in steady-state plasma glucose (SSPG) with continuous octreotide, insulin, and glucose infusion among apparently healthy persons. He attributed the lack of glycemic abnormality of persons with insulin resistance to compensatory hyperinsulinemia, although noting that there is great variation in insulin levels for a given level of insulin sensitivity. Similarly, there is variation in the correlations between obesity and insulin resistance, as well as between maximal aerobic capacity, a measure of physical fitness, and insulin sensitivity. Reaven suggested that adiposity and physical fitness each account for ∼25% of the variability in insulin sensitivity, with genetic factors, which he illustrated with the differences in insulin sensitivity between persons of European and persons of South Asian or Mexican ancestry and with the similarity in insulin sensitivity of related persons in a family, responsible for an additional 50% of this variation. Syndrome X, as Reaven originally termed it, included insulin resistance, hyperinsulinemia, dyslipidemia, hypertension, and increased risk of both diabetes and coronary heart disease. Other abnormalities associated with the IRS include glucose intolerance, small LDL particle size, postprandial accumulation of triglyceride-rich …