Overweight and Obesity Enlarges Teenagers' Hearts
Teen Obesity and Heart
The effects of excess weight on heart health can be seen even in adolescents, with abnormal enlargement and impaired pumping function evident in subjects by age 20, according to a new study in the June 6, 2006, issue of the Journal of the American College of Cardiology.
"Heart damage starts very early in the natural history of obesity. We need to work on our young people, to prevent catastrophic effects later on," said Giovanni de Simone, M.D., F.A.C.C. from the New York Presbyterian Hospital-Weill Medical College of Cornell University in New York, New York and the Federico II University Hospital School of Medicine in Naples, Italy.
The Strong Heart study (SHS) is a longitudinal study of cardiovascular risk factors and cardiovascular disease that enrolled 4,549 people in American Indian communities in Arizona, Oklahoma, and North and South Dakota. This analysis included data from examinations of 460 participants age 14 to 20 years (245 girls and 215 boys). The researchers used ultrasound and other methods to measure the size, shape and pumping function of the teenagers' hearts.
The left ventricles of the hearts of both overweight and obese teenagers were larger and heavier than those of normal weight participants; but the obese teenagers also showed signs of impaired heart function. The changes were not entirely explained by changes by high blood pressure.
"Our findings demonstrate that, even among adolescents at a mean age under 18, severity of abnormality in body build also parallels early cardiac changes, including high prevalence of left ventricular hypertrophy and increased hemodynamic load, paralleling previous findings and suggesting that increased left ventricular mass occurs to sustain the increased cardiac workload," the study authors wrote.
"The main findings are that, when obesity is present, something happens in our hearts to increase its size and wall thickness, which cannot be understood by measurement of blood pressure. This excess of cardiac mass, which we call 'inappropriate' in connection to cardiac workload, is also associated with a general impairment of the function of the heart to push blood into the arterial tree and also to distend its cavity to receive the blood returning from the periphery," Dr. de Simone said.
He said that these results underscore the need to fight excess weight in children, since the damaging effects are evident even before adulthood.
Although the participants in this study were all members of American Indian communities, Dr. de Simone said that he believes similar effects would be seen in overweight and obese children from other communities.
"The analysis was performed in an American Indian population and whether these results can be generalized to other ethnic groups needs to be demonstrated. However, similar analyses previously performed in other ethnic groups, such as Caucasians and African Americans, have suggested similar association between left ventricular mass and adiposity, independently of other cardiovascular risk factors," the authors wrote.
In an editorial in the journal, Stephan von Haehling, M.D., Wolfram Doehner, M.D., Ph.D., and Stefan D. Anker, M.D., Ph.D. from the Imperial College School of Medicine in London, United Kingdom and the Charit