Approximately 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 annually, according to estimates from a major national study called SEARCH for Diabetes in Youth.
SEARCH, a multi-center study of childhood diabetes in racially and ethnically diverse populations, is the largest surveillance effort of diabetes among youth under the age of 20 conducted in the United States to date. The study covers 10 locations across the country where about 5.5 million children live.
In a report in the June 26, 2007, issue of the Journal of the American Medical Association (JAMA) , study investigators identified 2,435 youth who were diagnosed with type 1 and type 2 diabetes in 2002 and 2003. The estimated overall incidence of diabetes in youth is 24.3 per 100,000 per year.
“The number of youth with newly diagnosed diabetes varies across major U.S. racial and ethnic groups as well as across age groups,” said lead author Dana Dabelea, MD, PhD, an associate professor of preventive medicine at the University of Colorado at Denver and Health Sciences Center's School of Medicine, and SEARCH principal investigator (PI) for the Colorado site.
In children under the age of 10, most had type 1 diabetes, previously known as insulin-dependent diabetes, regardless of their race or ethnicity. Even among older youth ages 10-14, type 1 diabetes was frequent among non-Hispanic white (32.0 per 100,000 per year), African-American (19.2 per 100,000) and Hispanic adolescents (19.2 per 100,000 per year), but was much less common among Asian Pacific Islander (8.3 per 100, 000 per year) and American Indian youth (7.1 per 100,000 per year). In all age groups, the highest rates of type 1 diabetes were observed in non-Hispanic white boys and girls.
SEARCH estimates of type 1 diabetes incidence are higher than the incidence of insulin-dependent diabetes mellitus reported by previous U.S. childhood diabetes registries. Type 1 diabetes is an autoimmune disease in which a person's own immune cells attack and destroy the beta cells of the pancreas, which produce the hormone insulin needed for survival. Researchers believe that the disease arises from a combination of susceptibility genes and an environmental trigger or triggers, such as an infectious agent or dietary component, that have not yet been identified.
The study also found that newly diagnosed type 2 diabetes was extremely rare in children under age 10 and gradually increased with age. Among minority adolescents and young adults 15-19 years of age high rates were documented among American Indian (49.4 per 100,000 per year), Asian-Pacific Islander (22.7 per 100,000 per years), African American (19.4 per 100,000 per year) and Hispanic (17.0 per 100,000 per year) youth. Although still relatively infrequent, type 2 diabetes was, nevertheless, present among non-Hispanic white youth 15-19 years of age (5.6 per 100,000 per year).
The incidence of type 2 diabetes in youth is consistent with the increasing rates of type 2 diabetes in adults. In both adults and children, this form of diabetes is closely linked to obesity, physical inactivity and a family history of type 2 diabetes.
“Reports of increasing incidence of both type 1 and type 2 diabetes in youth have been among the most concerning aspects of the evolving diabetes epidemic,” said Ann Albright, PhD, and director of the CDC's Division of Diabetes Translation. “The SEARCH study has provided a clear picture of diabetes burden among youth of all US major racial/ethnic groups. These estimates are essential to ultimately design and implement public health efforts to prevent type 1 diabetes, once prevention strategies are identified, and type 2 diabetes, and to reduce the risk for both acute and chronic complications of diabetes in youth.”