A new study finds the incidence of diabetes in the United States is far greater than previously thought, a finding that suggests the U.S. healthcare may be severely strained in dealing with this epidemic. The study says nearly 13 percent of adults aged 20 and older have diabetes, but 40 percent of them have not been diagnosed, according to epidemiologists from the National Institutes of Health and the Centers for Disease Control and Prevention. The researchers found another 30 percent of adults have pre-diabetes, a condition marked by elevated blood sugar that is not yet in the diabetic range.

 

“We’re facing a diabetes epidemic that shows no signs of abating, judging from the number of individuals with pre-diabetes,” says lead author Catherine Cowie of the National Institute of Diabetes and Digestive and Kidney Diseases.

 

The study, reported in the Diabetes Care, looks at newly available data from an Oral Glucose Tolerance Test. Diabetes is especially common in the elderly with nearly one-third of those age 65 and older having the disease.

 

Diabetes is a group of diseases marked by high levels of blood glucose resulting from defects in insulin production, insulin action, or both, researchers say. It is the most common cause of blindness, kidney failure, and amputations in adults and a leading cause of heart disease and stroke. Type 2 diabetes accounts for up to 95 percent of all diabetes cases and virtually all cases of undiagnosed diabetes. Pre-diabetes, which causes no symptoms, substantially raises the risk of a heart attack or stroke and of developing type 2 diabetes, they say.

 

The researchers found that minority groups continue to bear a disproportionate burden. The prevalence of diabetes, both diagnosed and undiagnosed, in non-Hispanic blacks and Mexican-Americans stands about 70 to 80 percent higher than that of non-Hispanic whites. They also found that diabetes prevalence was virtually the same in men and women, as was the proportion of undiagnosed cases. Even though diabetes is rare in youth ages 12 to 19 years, about 16 percent have pre-diabetes, they said.

 

“These findings have grave implications for our health care system, which is already struggling to provide care for millions of diabetes patients, many of whom belong to vulnerable groups, such as the elderly or minorities,” says Dr. Griffin P. Rodgers, director of the National Institute of Diabetes and Digestive and Kidney Diseases. “Of paramount importance is the need to curb the obesity epidemic, which is the main factor driving the rise in type 2 diabetes.”

 

The survey involved 7,267 people, who represented a national sample of persons aged 12 years and older. Participants were interviewed in their homes and received a physical exam, the researchers say.

 

“It’s important to know if you have diabetes or pre-diabetes, because there's so much you can do to preserve your health,” says Joanne Gallivan, director of the National Diabetes Education Program for the NIH. “You should talk to your health care professional about your risk. If your blood glucose is high but not high enough to be diagnosed as diabetes, losing a modest amount of weight and increasing physical activity will greatly lower your risk of getting type 2 diabetes. If you already have diabetes, controlling your blood glucose, blood pressure, and cholesterol will prevent or delay the complications of diabetes.”

 

Researchers say people over age 45 should be tested for pre-diabetes or diabetes. Those younger than 45 who are overweight and have another risk factor should ask their health care provider about testing, they say.