NEW ORLEANS — The arteries of obese and dyslipidemic children resemble those of middle-aged adults, possibly heralding the early onset of cardiovascular disease, according to a study presented at the annual scientific sessions of the American Heart Association.
“This is a wake-up call,” said coauthor Dr. Geetha Raghuveer, a cardiologist at Children's Mercy Hospital, Kansas City, Mo., who presented the findings. She noted that childhood obesity has already been shown to “track” into adulthood and to pose multiple risks to the vasculature.
Dr. Raghuveer and colleagues at the University of Missouri, Kansas City, and Children's Mercy Hospital measured the carotid artery intima-media thickness (CIMT) by ultrasound in 34 boys and 36 girls whose average age was 13 years. Most were obese, with a mean weight of 64 kg and mean body mass index of 26 kg/m
Most of the 70 also had abnormal lipid levels. Total cholesterol was greater than 170 mg/dL in 59 children and LDL cholesterol was above 110 mg/dL in 51; in 43 children, HDL cholesterol was less than 35 mg/dL and triglycerides were above 100 mg/dL.
To characterize the state of the carotid arteries in these children, the investigators plotted the CIMT measurements against previously published normative data for 45-year-olds matched by sex and race. The images revealed “advanced vascular age” in 75% of this young obese cohort. Mean CIMT was 0.45 mm, and maximum was 0.75 mm.
“We found that the state of the arteries in these children is more typical of 45-year-olds than of people their age,” reported Dr. Raghuveer. She noted that there are no normative standards of CIMT in children against which to compare the findings.
For example, a 12-year-old white male was shown to have a CIMT of 0.54 mm. Plotted against that of a 45-year-old male, this CIMT measurement fell between the 25th and 50th percentiles of the adult (0.50 and 0.57 mm, respectively). The researchers labeled the arteries as having “advanced age” if the CIMT exceeded the 25th percentile for their matched adult counterpart.
“We then wondered what might be favoring this early advancement in CIMT, and we found that those with advanced age had higher triglyceride levels,” Dr. Raghuveer reported. More children with advanced vascular age had elevated triglyceride levels than normal triglycerides.
The same was found for the 40 most obese children, or those with BMI above the 95th percentile. Of those, 26 had both a vascular age above the 25th percentile of adults as well as a triglyceride level above 100 mg/dL. Children with lower triglycerides were evenly divided between those who scored below or above the 25th percentile on the charts for 45-year-olds. When a cutoff of 120 mg/dL was used to define high triglyceride, the result was stable. “More kids in the high vascular age group had higher triglycerides,” she added.
“Vascular age was advanced the furthest in the children with obesity and high triglyceride levels, so the combination of obesity and high triglycerides should be a red flag to the physician that a child is at high risk of heart disease,” Dr. Raghuveer commented.
“Our take-home message is that obese children with abnormal lipids have arterial wall changes in association with cardiovascular risk factors quite early in life, and these can progress over time,” she concluded.
Future research should evaluate whether risk factor modification can change the vasculature over time, she said. “We are hoping that it can,” Dr. Raghuveer added. “These children do not have hard, calcified arterial plaque as we see in older people, and hopefully we can document some regression with changes in lifestyle [and] behaviors, and if need be, drug therapy.” Currently, children at her clinic who are identified as having advanced vascular age receive nutrition and exercise counseling.