The first analysis of diabetes trends among American youth reveals that the prevalence of both type 1 and type 2 increased substantially in that demographic over the past decade.
The researchers also found that complications such as nerve damage already are emerging in young people, raising concerns about the long-term health consequences for this and subsequent generations if the trend is not reversed, as reported June 9 in Philadelphia at the American Diabetes Associations 72nd scientific sessions.
The SEARCH for Diabetes in Youth study, funded by the U.S. Centers for Disease Control and Prevention and the National Institutes of Health, assesses diabetes burden in children and young adults under age 20 in five geographically dispersed populations that encompass the ethnic diversity of the U.S. Investigators found that overall, the prevalence of type 2 diabetes had increased 21% among American youth from 2001 to 2009, while type 1 diabetes rose 23%.
These data suggest nearly 189,000 Americans younger than 20 had diabetes during that period, including more than 19,000 with type 2.
Giuseppina Imperatore, MD, PhD, medical epidemiologist with the Division of Diabetes Translation at the CDC, said Type 2 diabetes has become increasingly prevalent in young people. “Weve known this was happening for a while, but now we have data that tell us just how big a problem it has become,” she said.
Additionally, she said, the number of young people worldwide diagnosed with type 1 diabetes has grown at an annual rate of about 3%, and preliminary data indicate a similar trend among U.S. youth.
This is of grave concern, because these youth will live with diabetes most of their lives and may develop diabetes-related complications, such as heart and kidney disease, nerve damage and vision problems, at a much younger age, she said. In fact, preliminary data suggest that complications may already be developing in this generation.
Complications an issue
Preliminary findings presented during the scientific sessions indicated that:
• Many children and adolescents with diabetes already show measurable signs of peripheral neuropathy, which could increase their future risk of lower-limb amputations.
• A pilot study, which looked at a subset of youth with type 1 and type 2 diabetes, found early indications of cardiovascular autonomic neuropathy, suggesting these youth are at increased risk for future cardiovascular disease.
• Young people with type 2 diabetes are more likely to have protein in the urine than youth with type 1, suggesting a greater risk for kidney disease later in life.
• Youth with diabetes who watched television for three or more hours per day had higher A1C and triglyceride levels than those who watched less television. Other lipids, such as cholesterol, did not appear to be affected by duration of television viewing.
The study showed that the proportion of youth with type 2 diabetes was highest among American Indian and non-Hispanic black youth, and in these groups the rate did not change over time. The proportion of Hispanic and non-Hispanic white youth with type 2 diabetes was lower but increased over time. The researchers said a longer study period is needed to fully quantify these trends in all racial groups.
Dana Dabelea, MD, PhD, professor of epidemiology and pediatrics at the University of Colorado, Denver, noted that the risk of early-onset type 2 diabetes is heavily affected by exposure to maternal diabetes or obesity in the womb.
“The vicious cycle of obesity creates a trans-generational problem as the offspring of women who are obese or who have type 2 diabetes during pregnancy are more likely to develop diabetes early in life,” she said.
Type 1 on the rise
Type 1 diabetes, shown in previous studies of European and worldwide registries to be on the rise in recent years, is not believed to be affected by lifestyle in the same way as type 2. The reasons for its rise are unknown, but researchers are investigating several hypotheses.
One theory is that children and infants in contemporary environments are less exposed to viruses and bacteria that help the immune system mature, increasing their subsequent risk for type 1. Other possibilities include changes in the environment that encourage kids to grow faster and gain more weight early in life, which overloads the beta cells and triggers and autoimmune attack; and changes in the diet of infants related to when foods are introduced.