Joana E. Kist-van Holthe, MD, PhD, from VU University Medical Center in Amsterdam, and colleagues reported that, of the 255 children between the ages of 2 and 18 whose cardiovascular risk factors were available, 56% had hypertension, 14% had high blood glucose, and 54% had low HDL cholesterol.
They defined severe obesity as a body mass index (BMI) of 20.5 kg/m2 for a 2-year-old, 31 for a 12-year-old, and 35 for an 18-year-old.
"Remarkably," they said, 62% of those severely obese children ages 12 and younger already had one or more of these risk factors.
Researchers noted that, although there is a global awareness of the increasing prevalence of obesity in children and of the cardiovascular risks associated with it, data on various categories and consequences of severe childhood obesity are lacking.
But such data are important for healthcare providers and in forming public health policy "as they give an indication of the need for early detection, timely treatment, and the development of interventions for this specific group."
The researchers gathered data on newly diagnosed cases of severe obesity from 2005 to 2007 supplied by pediatricians in general hospitals.
Of the 307 newly diagnosed cases of severe obesity, 52% were boys, and boys 12 and under tended to be heavier than their adolescent counterparts. With girls it was the opposite, as the adolescents tended to be more obese than the younger girls.
Interestingly, 40% of this severely obese cohort were of non-ethnic Dutch origin, included those of Turkish, Moroccan, and Surinamese backgrounds. The researchers said this finding is in line with other studies that showed an increased risk for obesity in these ethnic groups compared with Dutch children.
Overall, the investigators found that 67% of the children had at least one cardiovascular risk factor; 17% had at least two; 8% at least three, and 2.5% at least four.
High blood pressure was the most prevalent risk factor, occurring in more than half of all the children and in more than half of children 12 and younger. However, boys older than 12 tended to have more risk factors than the other age and sex categories. Specifically, more older boys tended to have high triglycerides and low HDL cholesterol. More older girls as well were reported to have low HDL cholesterol compared with those 12 and younger.
Although 14% of the entire cohort exhibited impaired fasting glucose, only two children had type 2 diabetes.
"The prevalence of impaired fasting glucose in this population is worrying, considering the increasing prevalence worldwide of type 2 diabetes in children and adolescents," the authors wrote. "Likewise, the high prevalence of hypertension and abnormal lipids in these children may lead to cardiovascular disease in (young) adulthood."
What’s most remarkable about the new Dutch study, however, is that it finds signs of heart disease even among much younger children still. Among the severely obese Dutch boys and girls aged 2 to 12, 62% showed one or more risk factors. Roughly half of those youngsters were hypertensive.
Writing in the medical journal Archives of Disease in Childhood, the Dutch researchers note that out of the hundreds of children diagnosed as severely obese, "Only one child was obese because of a medical cause," a hypothalamic tumor. The rest, it seems, were obese instead due to unhealthy lifestyle, a risk factor that continues to spread across the globe.
They also reported that nearly one in three of these severely obese children came from one-parent families. The researchers called for "specialized pediatric obesity centers for the intensive treatment of severely obese children."
They also called for "internationally accepted criteria for defining severe obesity and guidelines for the early detection and treatment of severe obesity and comorbidity."
The most common risk factor was hypertension, which was present in more than one-half of all severely obese children and of those younger than 12.
The Dutch study found a high prevalence of cardiovascular risk factors already present in severely obese children and adolescents, even those younger than 12 years old.
van Emmerik NM, et al "High cardiovascular risk in severely obese young children and adolescents" Arch Dis Child 2012; DOI: 10.1136/archdischild-2012-301877.