Diabetes: Are we underestimating its prevalence?

The number of adolescents with diabetes or prediabetes is higher than previously estimated, according to a new research letter published in the Journal of the American Medical Association.

Lead author Andy Menke, PhD, an epidemiologist with Social and Scientific Systems in Silver Springs, Maryland, says the new figures are not only startling, but they paint a grave picture for the future health of American teenagers.

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“These findings are important because diabetes in adolescence is associated with early onset of other risk factors for diabetes complications such as high blood pressure and cholesterol levels, as well as actual diabetes complications,” Menke says. “A relatively large proportion of adolescents with diabetes were unaware of the condition, particularly Hispanic and non-Hispanic black participants. We need to better educate people on the risk factors for type 1 and type 2 diabetes and ways to reduce risk, and improve screening for adolescents at high risk.”

Previous estimates place diabetes prevalence among teenagers at 0.25% but the new research places that estimate closer to 0.8%. Even more concerning, perhaps, was that 1 in 3 cases were undiagnosed and another 20% of the study group had prediabetes, according to the report.

“A large percentage of adolescents with diabetes are unaware of it, and these young people are likely to have type 2 diabetes. In addition, a large proportion of adolescents have prediabetes, which puts them at high risk for type 2,” Menke says. “There are effective treatments for diabetes, but those treatments are not useful to people who have not been diagnosed.”

Although the study didn’t differentiate teenagers with type 1 versus type 2 diabetes, Menke says the findings suggest that more teenagers are developing type 2, in addition to the estimated 87% of diabetic adolescents with type 1 diabetes.

The study was conducted using data from the 2005-2014 National Health and Nutrition Examination Survey and was funded by the National Institutes of Health’s National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). More than 2600 teenagers aged 12 to 19 years were randomly selected for fasting blood glucose tests, and completed questionnaires to provide demographic information as well as data on whether they had already received a diabetes diagnosis from a physician.

Of the teenagers tested, 62 had diabetes; 20 had diabetes but were previously undiagnosed; and 512 had prediabetes. Overall, the weighted prevalence of adolescents in the study was 0.8% with diabetes; 28.5% with undiagnosed diabetes; and 17.7% with prediabetes.

NEXT: Prediabetes prevalence

Prediabetes prevalence was most common with males (22%) compared with females (13.2%), and was highest in non-Hispanic black and Hispanic participants. Undiagnosed diabetes also was more prevalent in non-Hispanic black and Hispanic populations, according to the study.

“At 18%, the prevalence of prediabetes was higher than we anticipated. We expected the prevalence of diabetes to be a little higher than in previous studies, because previous studies were mostly limited to diagnosed diabetes, which means they would have missed cases of undiagnosed diabetes,” Menke says, adding this study was the first to use all 3 markers-A1c, fasting plasma glucose, and plasma glucose from an oral tolerance test-recommended by the American Diabetes Association (ADA) in the adolescent population.

Although there are effective preventive measures and treatment strategies for diabetes and prediabetes, Menke notes that they don’t work unless the clients know they have the condition or are at risk.

“We need to better educate people on the risk factors for type 1 and type 2 diabetes and ways to reduce risk, and improve screening for adolescents at high risk,” Menke says. “While at present there are no screening recommendations specifically in adolescents, it would be prudent to better screen those at high risk for diabetes based on guidelines for their adult counterparts.”

Next: Taking control of T2D

Among individuals aged younger than 20 years, the ADA estimates the prevalence of diabetes at 0.25%-or 208,000 cases, with the majority having type 1 diabetes (18,436) followed by type 2 diabetes (5089).

American Indians/Alaska Natives are known to have the highest prevalence at 15.9%, followed by non-Hispanic blacks at 13.2%; Hispanics at 12.8%; Asian-Americans at 9%; and non-Hispanic whites at 7.6%.

Whereas type 2 diabetes has mainly been viewed as a disease that develops in overweight individuals over the age of 40 years, prevalence is certainly growing among children aged 10 to 19 years.

The NIDDK says the increasing prevalence of type 2 diabetes in children and adolescents can be tied to the growing obesity epidemic, noting that 16% to 17% of children and adolescents aged 2 to 19 years have a body mass index greater than or equal to the 95th percentile for their age and weight bracket-a statistic that has doubled over the last 20 years.

Although type 1 diabetes is still most common among children, it is not necessarily preventable or caused by lifestyle factors, but rather is an autoimmune disease in which the body destroys its own insulin-producing beta cells in the pancreas.

The Centers for Disease Control and Prevention (CDC) says non-Hispanic white children have the highest rate of new type 1 diabetes cases, but minorities make up the bulk of type 2 diabetes cases.

From 2008 to 2009, the CDC reveals that new cases of type 2 diabetes rose the most in the American Indian/Alaska Native population, from about 5 per 100,000 cases per year to about 35 per 100,000 cases per year, followed by non-Hispanic blacks with a jump from about 18 per 100,000 cases per year to roughly 45 per 100,000 cases per year.

Comorbidities associated with diabetes include kidney and cardiovascular disease, stroke, and vision problems. The ADA notes that diabetes is the seventh leading cause of death in America, but there are methods for prevention.

A healthy diet and regular exercise are key to staving off diabetes, and the ADA says individuals with prediabetes can lower their risk of developing diabetes by 58% with a 7% weight loss and moderate exercise.