This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Diabetes Introduction to Diabetes 1-1 1. Introduction to Diabetes Created: July 7, 2004 Diabetes mellitus is characterized by abnormally high levels of sugar (glucose) in the blood. When the amount of glucose in the blood increases, e.g., after a meal, it triggers the release of the hormone insulin from the pancreas. Insulin stimulates muscle and fat cells to remove glucose from the blood and stimulates the liver to metabolize glucose, causing the blood sugar level to decrease to normal levels [http://www.ncbi.nlm.nih.gov:80/books/bv.fcgi?call=bv.View.. ShowSection&rid=mcb.figgrp.5903]. In people with diabetes, blood sugar levels remain high. This may be because insulin is not being produced at all, is not made at sufficient levels, or is not as effective as it should be. The most common forms of diabetes are type 1 diabetes (5%), which is an autoimmune disorder, and type 2 diabetes (95%), which is associated with obesity. Gestational diabetes is a form of diabetes that occurs in pregnancy, and other forms of diabetes are very rare and are caused by a single gene mutation. For many years, scientists have been searching for clues in our genetic makeup that may explain why some people are more likely to get diabetes than others are. "The Genetic Landscape of Diabetes" introduces some of the genes that have been suggested to play a role in the development of diabetes. Diabetes Introduction to Diabetes 1-2 Classification Diabetes is classified by underlying cause. The categories are: type 1 diabetesan autoimmune disease in which the body's own immune system attacks the pancreas [http://www.ncbi.nlm.nih. gov:80/books/bv.fcgi?tool=bookshelf&call=bv.View..ShowSection&rid=imm.figgrp.1942], render- ing it unable to produce insulin; type 2 diabetesin which a resistance to the effects of insulin or a defect in insulin secretion may be seen; gestational diabetes; and other types. Table 1 com- pares the presentation (phenotype) of type 1 and type 2 diabetes. Table 1. Comparison of Type 1 and Type 2 Diabetes Type 1 diabetes Type 2 diabetes Phenotype Onset primarily in childhood and adolescence Onset predominantly after 40 years of age* Often thin or normal weight Often obese Prone to ketoacidosis No ketoacidosis Insulin administration required for survival Insulin administration not required for survival Pancreas is damaged by an autoimmune attack Pancreas is not damaged by an autoimmune attack Absolute insulin deficiency Relative insulin deficiency and/or insulin resistance Treatment: insulin injections Treatment: (1) healthy diet and increased exercise; (2) hypoglycemic tablets; (3) insulin injections Genotype Increased prevalence in relatives Increased prevalence in relatives Identical twin studies: <50% concordance Identical twin studies: usually above 70% concordance HLA association: Yes HLA association: No * Type 2 diabetes is increasingly diagnosed in younger patients....
View Full Document
- Spring '11