Asian and Pacific islander children in the United States have much higher rates of diabetes than children in many Asian countries, say the latest findings of a 10-year study of the disease.

Researchers were expecting higher incidence rates of type 2 diabetes in the American children, since that form of the disease is closely linked to obesity. But they were surprised at data indicating higher rates of type 1 diabetes as well, said Dr. Beatriz Rodriguez, a professor at the University of Hawai'i's John A. Burns School of Medicine and principal investigator at the SEARCH for Diabetes in Youth study site in Hawai'i, one of six study sites around the nation.

The causes of type 1 diabetes — an autoimmune disorder involving the pancreas that requires patients to take insulin in order to survive — are less clear. Rodriguez, who is also a researcher with the Pacific Health Research Institute, said a combination of genetic and nongenetic factors, such as infections at birth, toxins, and early cessation of breastfeeding, are suspected.

The SEARCH study found that incidence rates of type 1 diabetes in Asian and Pacific islanders under age 14 in the United States are at least three times higher than the rates in Japan, Korea, Shanghai, Taiwan, Thailand and Singapore.

Rates for type 2 diabetes also were substantially higher among Asian and Pacific islander youths in the U.S., according to the study. For example, the rate was 2.6 per 100,000 in Japan and 6.5 per 100,000 in Taiwan, compared with 12.1 per 100,000 in the United States.

Type 2 diabetes occurs when the body develops resistance to insulin. Risk factors include a family history of the disease, obesity, physical inactivity and race. Asians, Pacific islanders, African Americans and Hispanics all have higher rates of type 2 diabetes than whites.

The SEARCH study is the largest-ever national surveillance of youth with diabetes. More than half of the Asian and Pacific islander children in the study are from Hawai'i, said Rodriguez, who has been able to identify 550 youngsters with diabetes in the state.

Earlier study findings showed that 70 percent of Asian children and 100 percent of the Pacific island youngsters with type 2 diabetes are obese. Rodriguez said the research also found a higher than expected percentage of children with type 1 diabetes are overweight or obese.

According to the study, approximately 1 in 8,200 Asian and Pacific islander youth between the ages of 10 and 19 is diagnosed with type 2 diabetes each year. Only Navajo youth have a higher rate: 1 in 2,542.

Complications from diabetes include heart disease, stroke, blindness and kidney failure. Rodriguez said the findings underscore the importance of public health efforts in Hawai'i and elsewhere to address obesity and prevent diabetes among Asian and Pacific island children and other minority groups.

Other newly released findings show the annual incidence rate of type 1 diabetes among U.S. non-Hispanic white youth is one of the highest in the world: 1 in about 4,200. And although high rates of type 2 diabetes have been documented in African-American youth, the study also found type 1 among African-American children is more common than expected.