Study Ties Young Women's Obesity, Higher Risk of Heart Enlargement

Study Ties Young Women's Obesity,
Higher Risk of Heart Enlargement

ATLANTA -- The obesity epidemic sweeping the U.S. is yielding an early and troubling condition in young people: enlarged hearts.

A study of 575 otherwise healthy young women found that 25% had abnormally large hearts. More disturbing, 20% of the women in the study were diagnosed with left ventricular hypertrophy, an enlargement of the heart's main pumping chamber -- and a condition highly predictive of future heart problems. Nearly all of the women with the condition were obese; the average age of the group was 20.

[Karl Note:  Might it be possible that free radical damage, rather than poor diet, could be the cause of this condition?]

"To us it was terribly surprising that these women already have hypertrophy," says Thomas R. Kimball, a researcher at Cincinnati Children's Hospital and an author of the report presented Tuesday at the annual scientific meeting of the American College of Cardiology. The findings are "not good news for them," he adds, particularly if they follow unhealthy diets or have poor exercise habits.

The results underscore the growing public health concern about the increasing numbers of Americans -- especially young people -- who are overweight or obese. The U.S. Centers for Disease Control and Prevention estimates that 13% of the nation's children and adolescents are seriously overweight. Some believe the total is even higher. That, in turn, is leading to a sharp rise in Type 2 diabetes among young people, a debilitating health problem that is usually viewed as a disease of middle age or later.

RISKS People with enlarged heart muscles are at higher risk for: • Premature sudden death and death from heart attack   • Irregular heart beats   • Failure to supply sufficient nourishing blood to heart tissue     Source: Cincinnati Children's Hospital

The process of heart disease "clearly begins at a very young age," says Daniel Jones, director of hypertension at University of Mississippi Medical Center, Jackson. "Children who are overweight are much more likely to get heart disease earlier in life" than other people, he adds.

Left ventricular hypertrophy, common among people with chronic high blood pressure, leads to a weakening of the heart muscle, undermining its ability to efficiently pump blood through the body. It is also a precursor to congestive heart failure, a lethal problem that already afflicts about five million Americans.

Exactly why obesity might be linked to an enlarged heart isn't clear. "There's not a lot known about it," Dr. Jones says, though people who are obese with high blood pressure are at particularly high risk for the condition.

[Karl Note:  One reason to avoid naming free radicals as the cause is that there is no drug or medical procedure known to resolve free radicals, other than chelation, and whenever you can blame the patient for a disease, he feels guilty enough to pay for the drugs or procedures claimed to be helpful.  Can free radical damage cause obesity -- might both free radical damage and obesity be caused by something in common -- metal toxicity?]

Surprisingly, the report's author notes, nearly all of the women in the study had normal blood pressure, suggesting that obesity itself is playing the dominant role in affecting the heart muscle. While studies in adults indicate that lowering blood pressure, either through diet or medication can stall or reverse left ventricular hypertrophy, Dr. Kimball says that for these women it may take aggressive dietary changes and weight loss to stem the harmful process and improve their chances for a healthy later life.

The women are part of a long-term study that began about a decade ago before they reached puberty. They were a representative sample of girls in public and parochial schools in Cincinnati being studied to learn about the development of cardiovascular risk factors in girls -- where research has been deficient. About half the participants are African-American. By the time they reached age 20, when they were evaluated for the current study, about half the participants were obese and most of the obese women were African-American. The last finding is consistent with other research and highlights concerns among many public health officials about finding ways to reach young black women with programs to help reduce or prevent obesity.

Dr. Kimball says the findings didn't detect a direct link between being black and the enlarged heart condition.

Considering the entire group of participants, the findings also reflect difficulties in getting teenagers to heed public health recommendations. "It says something about teenage behavior," says Richard Pasternak, director of preventive cardiology at Massachusetts General Hospital and a cardiologist at Harvard Medical School. "... We have to figure out how to [promote] the attitude that they need to take care of their health for the long term."

Dr. Kimball says that he and his colleagues at Cincinnati Children's Hospital are studying a younger group of children and are finding that abnormalities in hearts of obese children begin to form in the early teens or even sooner. Children in that study are now participating in weight-reduction programs to see if that may prevent or reverse the course of heart changes, which doctors call remodeling. So far, modest reductions in weight haven't led to improvements in heart remodeling, suggesting that it may take profound weight loss to undo or mitigate the damage caused by early obesity.

Write to Ron Winslow at ron.winslow@wsj.com¹

Updated March 20, 2002