Insulin resistance in the morbidly obese adolescent

Abstract

Multiple causes can drive the development of insulin resistance in children and adolescents, such as sedentary behavior, specific dietary elements, and genetic factors, yet the most common cause in this age group is obesity. Obesity is defined in general as an excess adipose tissue. Adipose tissue may be stored in several depots which differ in their localization, anatomical structure, as well as their metabolic profiles. While most fat is accumulated in adipose tissue, some fat may be deposited within and outside of cells in other tissues such as the liver and muscle. In these tissues, lipids may serve as important sources of energy, yet an excess of their intracellular accumulation may have deleterious effects on specific metabolic processes and intracellular signal transduction pathways. Thus, total body fat serves as a crude parameter in the definition of obesity that may be useful in epidemiological studies, yet has limited utility in the characterization of the metabolic phenotype of an obese individual. In order to provide clinical insights into the impact of the amounts of fat in an individual, one must have a precise description of the distribution of fat into specific depots as well as the deposition of fat in various tissues, specifically in insulin-responsive organs.