Obese Kids at Risk for Early Death

By Kristina Fiore, Staff Writer, MedPage Today
Published: February 10, 2010
Reviewed by Dori F. Zaleznik, MD; Associate Clinical Professor of Medicine, Harvard Medical School, Boston. Earn CME/CE credit
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Action Points

* Explain that children with obesity, glucose intolerance, or high blood pressure may be at risk of premature death, but those with hypercholesterolemia were not at increased risk.

Children with obesity, glucose intolerance, or high blood pressure may be at risk of premature death, according to a longitudinal study of Native Americans.

Youngsters from two Arizona tribes who had the highest body mass index (BMI) were more than twice as likely as those with the lowest BMI to die prematurely from endogenous causes, and those with the worst glucose intolerance had a 73% higher risk of death than those with the best control, Paul W. Franks, PhD, now of Umeå Universitet in Umeå, Sweden, and colleagues reported in the Feb. 11 issue of the New England Journal of Medicine.

Youths with high cholesterol weren't at increased risk for premature death, but the researchers said that may be because Native Americans have lower cholesterol levels than most other ethnic groups.

"The pattern of relationships between the risk factors and observed mortality supports the view that childhood obesity is an early metabolic derangement, whereas most of the other risk factors evolve later," they wrote.

While the study may not be applicable to the general population, it may "be applicable to those vulnerable populations -- the poor, African Americans, Hispanics -- who today have a comparably high prevalence of childhood obesity," said Barbara J. Moore, PhD, president of Shape Up America!, an organization that raises obesity awareness.

But Nicolas Stettler, MD, of the Children's Hospital of Philadelphia, said the study offers the opportunity to see what happened to a group of children who had a high rate of obesity 20 to 30 years ago -- a rate similar to the general population today.

Because of this, Stettler says he worries that a similar high rate of early death could be in the general population's near future.

For their study, the researchers assessed 4,857 children from the Gila River Indian Community in Arizona, most of whom were Pima or Tohono O'odham Indians. All were born between 1945 and 1984, and none had diabetes.

All of the children were assessed with glucose tolerance tests.

During a median follow-up of about 24 years, 559 patients died before they reached age 55, with 166 of those deaths due to endogenous, or internal, causes.

The researchers found that BMI was positively associated with the risk of premature death from endogenous causes, including alcoholic liver disease, cardiovascular disease, infections, cancer, diabetes or diabetic nephropathy, and acute alcohol or drug overdose (RR 1.40, 95% CI 1.20 to 1.63).

Rates of death from endogenous causes more than doubled among children with the highest BMI, compared with those with the lowest (RR 2.30, 95% CI 1.46 to 3.62).

The association between BMI and premature death was attenuated after adjusting for baseline glucose levels, cholesterol levels, and blood pressure -- but it remained significant (RR 1.41, 95% CI 1.19 to 1.67).

Rates of premature death from endogenous causes among youngsters with the worst glucose intolerance were 73% higher than those in the lowest quartile (RR 1.73, 95% CI 1.09 to 2.74).

"The presence of impaired glucose tolerance in a child is sinister because it silently undermines health," Moore said. "The child feels poorly and does not know why, and may even think that the way he or she feels is perfectly normal."

There were no significant associations between overall premature death and childhood cholesterol levels or hypertension. But the latter was significantly associated with premature death from endogenous causes (RR 1.57, 95% CI 1.10 to 2.24).

The lack of an association between premature death and cholesterol levels may be due partly to the low proportion of deaths due to cardiovascular disease in the cohort, the researchers explained.

Also, they noted, cholesterol levels are lower in American Indians than "in most ethnic groups."

In an accompanying editorial, the CDC's Edward W. Gregg, PhD, cautioned that Pima Indians aren't always considered representative of the U.S. population because they have an especially high risk of diabetes.

However, he wrote, "the prevalence of impaired glucose tolerance among persons in the current study (4%) is similar to the current prevalence in the general population of U.S. adolescents (3%) and is far less than the prevalence among obese adolescents in the U.S. (9.5%)."

"Since the trends with respect to obesity and diabetes among the Pima Indians have been a reliable harbinger for trends in the rest of the U.S. population during recent decades," he continued, "the present study should intensify the debate about whether interventions that are initiated during childhood and young adulthood can affect our broader diabetes epidemic."

He added that it will be "important to convert these results into effective prevention policies."

Moore said addressing childhood obesity rather than high cholesterol is the "first order of business."

"There is evidence from the diabetes prevention program that weight loss will improve and in many instances reverse the impaired glucose tolerance and avert the development of diabetes altogether," she said. "The same is true for high cholesterol."

The study was supported by the National Institute of Diabetes and Digestive and Kidney Diseases, and by grants from the Swedish Diabetes Association, the Swedish Heart Lung Foundation, the Swedish Research Council, Umea University, and the Vasterbotten regional health authority.

Neither the researchers nor the editorialists reported conflicts of interest.

This article was developed in collaboration with ABC News.

Primary source: New England Journal of Medicine
Source reference:
Franks PW, et al "Childhood obesity, other cardiovascular risk factors, and premature death" N Engl J Med 2010; 362: 485-93.

Additional source: New England Journal of Medicine
Source reference:
Gregg EW, et al "Are children the future of type 2 diabetes prevention" N Engl J Med 2010; 362: 548-50.