Obese Children Have Heart Damage

Heart trouble can start early for obese children, a German research team found. Writing in the Journal of the American College of Cardiology, Norman Manger, MD, and colleagues compared blood pressure, low-density lipoprotein cholesterol, and glucose metabolism in 61 obese children with that of 40 children with healthy weights. The obese group had an average BMI of about 31 while the control group’s average BMI was about 20.

The team found that the obese group tended to have enlarged left-side and right-side cardiac chambers, thicker left ventricular walls, and increased left ventricular mass. They also found decreased Doppler-derived peak systolic velocity and regional basoseptal strain in the overweight kids. That group also showed impaired diastolic function.

“Childhood obesity is associated with significant changes in myocardial geometry and function, indicating an early onset of potentially unfavorable alterations in the myocardium,” Manger wrote.

Though it has long been known that obesity in adults is associated with heart failure, left ventricular dilation and other signs of cardiovascular problems, the team said its work shows “many of these abnormalities may already occur in childhood and adolescence.”

The researchers found that since the obese children had significantly higher blood pressure than the healthy-weight children, that could have played a role in the myocardial changes. They also suggested that insulin resistance might be contributing to the heart changes in the obese group. But “other explanations or confounding factors for disturbed systolic cardiac mechanics may account for the findings,” Manger wrote. “Insulin acts as a growth factor and stimulates the sympathetic nervous system with an increased presssor reaction to angiotensin, leading to hypertension, hypertrophy and fibrosis in the myocardium. “

The authors also said the study was not designed to determine whether the cardiac changes would reverse if the children later lost weight. They also noted that “The clinical significance of these changed values in obese children remains unknown and will require extensive longitudinal follow-up to ultimately determine their predictive value.”

The researchers work at the University of Leipzig.