Study finds childhood obesity increases early signs of cardiovascular disease

Jun 11 2009

At a press conference held today at The Endocrine Society's 91st Annual Meeting in Washington, D.C., Nelly Mauras, M.D., Division Chief of Endocrinology at Nemours Children's Clinic in Jacksonville, announced the results of a four year study with findings that show childhood obesity increases early signs of cardiovascular disease. Dr. Mauras' study was chosen for distinction among 5,000 abstracts that were submitted to the national conference.

The new study, supported by The Thrasher Research Fund of Salt Lake City, found that by as early as seven years of age, being obese may raise a child's future risk of heart disease and stroke, even without the presence of other cardiovascular risk factors such as high blood pressure. Conducted by researchers at Nemours Children's Clinic in Jacksonville and Dr. Charles DelGiorno from the Mayo Clinic, the investigation demonstrates that the unhealthy consequences of excess body fat starts very early. Obesity alone, according to the study, is linked to certain abnormalities in the blood that can predispose individuals to developing cardiovascular disease early in adulthood.

"Our findings suggest that we need more aggressive interventions for weight control in obese children, even for those who do not have the co-morbidities of the metabolic syndrome," said Dr. Mauras, principal investigator and senior author.

The metabolic syndrome is a cluster of risk factors that raise the risk of developing heart disease, stroke and diabetes. It is increasingly being diagnosed in children as obesity becomes a greater problem. Although debate exists as to its exact definition in general, an individual must have at least three of the following to receive a diagnosis of metabolic syndrome: increased waist circumference (abdominal fat), low HDL (good) cholesterol, high triglycerides (fats in the blood), high blood pressure and high blood glucose (blood sugar).

In establishing the study, the research team wanted to know if simple obesity could raise cardiovascular disease risk before metabolic syndrome develops. They screened more than 300 individuals aged seven to 18 years and included just those without features of metabolic syndrome, consisting of approximately 202 subjects. Of the subjects in the study there were 115 obese children and 87 lean children that served as controls; half were prepubetal and half in late puberty. Also, the obese children had a body mass index (a measure of body fat) above the 95th percentile for their sex, age and height.

To be eligible to participate in the study, the children and adolescents had to have normal fasting blood sugar levels, normal blood pressure and normal cholesterol and triglycerides. Lean control subjects could not have a close relative with type 2 diabetes, high cholesterol, high blood pressure or obesity. The latter group proved very difficult to find.

Also, all study participants underwent blood testing for known markers that predict the development of cardiovascular disease. These included elevated levels of C-reactive protein (CRP) which is a marker of inflammation, and abnormally high fibrinogen, a clotting factor, among others. Obese children had a 10 fold higher CRP and significantly higher fibrinogen concentrations, compared with age- and sex-matched lean control children. These abnormalities occurred in obese children as young as seven years old, long before the onset of puberty.

"The results were striking as the children were entirely healthy otherwise," Dr. Mauras stated. Although it is not yet known whether early therapeutic interventions can reverse high CRP and fibrinogen, she said that it would be prudent for health care providers to advise more aggressive interventions to limit calories and increase activity in "healthy" overweight children, even before the onset of puberty.

"Doctors often do not treat obesity in children now unless they have other features of the metabolic syndrome," she said. "This practice should be reconsidered."

Further studies by the group may offer insight into the effects of therapeutic interventions in these children.

About Nemours

Nemours, one of the nation's largest pediatric health systems, is dedicated to achieving higher standards in children's health. Nemours offers an integrated spectrum of clinical treatment coupled with research, advocacy, and educational health and prevention services extending to all families in the communities it serves. Starting with Alfred I. duPont's bequest over seventy years ago, Nemours has grown into a multi-dimensional organization offering personalized clinical and preventive care focused on children.

Nemours owns and operates the Alfred I. duPont Hospital for Children in Wilmington, Delaware and major children's specialty clinics in Delaware (Wilmington), Florida (Jacksonville, Orlando and Pensacola), Pennsylvania (Philadelphia and Bryn Mawr) and New Jersey (Atlantic City and Voorhees). Having recently received approval from the State of Florida, Nemours will establish a new full-service children's hospital in Orlando. KidsHealth.org, the world's most visited pediatric health care Web site for parents, kids and teens, is a project of Nemours.

Nemours employs over 4,200 individuals, including 430 pediatric physicians, specialists and surgeons who cared for approximately a quarter of a million children in 2007. The organization's goal is to align with parents, physicians, community leaders, children's advocates and elected officials to ensure optimal wellness for every child.