Type 1B Or Idiopathic Diabetes
Type 1 B diabetes is also referred to as idiopathic diabetes, or diabetes of unknown origin. This form of type 1 diabetes is not autoimmune in nature, and tests for islet cell antibodies will come up negative. People with type 1 B have an insulin deficiency and can experience ketoacidosis (a high blood sugar emergency), but their need for insulin injections typically waxes and wanes over time. Patients of African, Hispanic, or Asian descent are more likely to develop type 1 B diabetes.
Genetics And Heredity
Exactly what sets off the complex mechanisms behind beta cell destruction and eventual insulin dependence is not completely understood, but researchers believe that it is likely a genetic predisposition to the disease activated by an environmental trigger.
Human leukocyte antigens (HLA) are a set of surface blood proteins that help to control immune function. Two specific HLA markers HLA DR and HLA DQ help the immune system identify foreign invaders and have been specifically linked with type lA diabetes. But while everyone with type 1 diabetes is thought to have one of these genetic markers, not everyone with a marker goes on to develop diabetes. For this reason, genetic testing can be helpful in identifying the possibility of diabetes but not in determining with certainty that it will occur.
How do I know if I have type 1A or type 1 B diabetes?. The issue is largely an academic one. The expense and scarcity of autoantibody tests at this point in time makes them impractical for routine use, and knowing your type probably won't have any real bearing on the course of treatment. The overall approach to disease management is the same, even though type 1 B individuals may have some periods of insulin independence. In addition to statistical uncertainty, it is also cost prohibitive to use genetic testing to screen for type 1 diabetes, and because there are no known methods of delaying or preventing the disease if a genetic tendency is revealed, the test serves no practical purpose. In their 2003 Clinical Practice Recommendation, the American Diabetes Association recommends against routine genetic and autoantibody screening (Le., ICA, IAA, GAD) for type 1 diabetes outside of a clinical trial setting. However, in circumstances where it is unclear if a patient is type 1 or type 2 and early diagnosis may provide a way to preserve some degree of islet cell function, testing may be appropriate.
Heredity is a relatively small piece of the puzzle in predicting type 1 diabetes. Statistically, people with an immediate family member who has type 1 diabetes are fifteen times more likely than the general population to develop the disease. Yet only 10 percent of people with type 1 have a first degree relative with the disease. Having a parent with type 1 places you at an approximate 5 percent risk of developing the disease (2 to 3 percent for the mother and about 6 percent for the father). If you have a sibling with the disease, your risk is an estimated 6 percent. Looking at cases of type 1 in identical twin studies puts the role of heredity in an even better perspective. In cases where one identical twin develops type 1 diabetes, an estimated 30 to 70 percent of their twin siblings will develop it. In other words, having a carbon copy gene set of someone with diabetes isn't a guarantee that the disease will occur. Something in the environment must flip the switch.
U.S. epidemiological studies have found that Caucasians have a higher incidence of type 1 diabetes than Hispanics and African-Americans. Interestingly, geography also seems to playa part in the rates of type 1 diabetes among certain populations. For example, Finland and Sardinia have the highest incidence of type 1 diabetes worldwide, while Asian countries like Japan and China have extremely low rates of the disease.
A good way to remember the core difference between type 1 and type 2 diabetes is in terms of insulin processing. People with type 1 diabetes are insulin deficient, meaning their pancreas is producing little to no insulin. In contrast, most people with type 2 diabetes initially generate enough insulin, but because they are insulin resistant, their bodies can't use it to process blood glucose.