Thousands of children and teens diagnosed with diabetes each year in the U.S.

According to a major national study, as many as 15,000 children and adolescents in the United States are diagnosed with type 1 diabetes, and about 3,700 youth are diagnosed with type 2 diabetes each year.

The study called SEARCH looked at childhood diabetes in racially and ethnically diverse populations and is the largest yet to assess the level of diabetes among youngsters under the age of 20 in the United States.

SEARCH is a multi-center study which covers six clinics in California, Colorado, Hawaii, Ohio, South Carolina, and Washington and a population of about 5.5 million children.

The researchers identified 2,435 youths who were diagnosed with type 1 and type 2 diabetes in 2002 and 2003 and estimated the overall incidence of diabetes in youth to be 24.3 per 100,000 per year.

Type 1 diabetes which is sometimes called juvenile diabetes, occurs when the immune system runs amok and begins attacking itself, destroying insulin-producing cells in the pancreas needed to control blood sugar; people with type 1 diabetes must take daily insulin injections.

Type 2 which is often called adult onset diabetes usually occurs later on in life, often in middle-age.

Lead author Dr. Dana Dabelea, an associate professor of preventive medicine at the University of Colorado in Denver says in all age groups, the highest rates of type 1 diabetes were observed in non-Hispanic white boys and girls.

The study found that one in 3,000 non-Hispanic white children in this age group develop type 1 diabetes each year, compared with one in about 5,000 African-American and Hispanic youths and about 1 in 10,000, for Asian Pacific Islanders and American Indian children.

With type 2 diabetes, in the 15- to 19-year-old age group, American Indian children are hardest hit, with about one in 2,000 developing type 2 diabetes each year.

The study figures for type 1 diabetes are higher than previously thought and the researchers believe a combination of factors such as genetic and environmental triggers or an infectious agent or dietary component not yet identified, could be the cause.

The study also found that newly diagnosed type 2 diabetes was extremely rare in children under age 10 but gradually increased with age and although still rare type 2 diabetes was, nevertheless, present among non-Hispanic white youth 15-19 years of age (5.6 per 100,000 per year).

The appearance of type 2 diabetes in youth reflects the increasing rates in adults and in both cases this form of diabetes is closely linked to obesity, physical inactivity and a family history of type 2 diabetes.

Experts say the study provides a clear picture of diabetes incidence among all American youth and is important in that it will lead to prevention strategies to reduce the risk of complications associated with diabetes.

The researchers will continue to monitor the incidence of diabetes in youth in all of the various population groups through to 2009.

The study was funded by the Division of Diabetes Translation at the Centers for Disease Control and Prevention (CDC) and the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), a part of the National Institutes of Health (NIH).

Almost 21 million Americans have diabetes, which causes 5 percent of all deaths globally each year; most have type 2, which can damage blood vessels, leading to loss of toes and limbs, blindness, heart disease and death.

The study is published in the Journal of the American Medical Association (JAMA).