A pattern of weight gain beginning in childhood can lead to an enlarged heart by early adulthood, according to an article in the November 23rd issue of Circulation.
American researchers with the Bogalusa Heart Study followed 467 children for an average of 21.5 years. They found that adiposity beginning in childhood was a consistent predictor of heart size in early adulthood. By adulthood, both body mass index and a high systolic blood pressure were independent predictors of left ventricular hypertrophy.

“We have observations taken from children 20 to 30 years ago that could be compared with similar medical data obtained in early adulthood,” said Gerald S. Berenson, MD, the study’s principle investigator. “It shows that a high childhood body mass index predicts heart enlargement in adulthood. This underscores the importance of obesity in the development of early cardiac enlargement and the need for early prevention. Children need to eat more healthy diets and exercise. Health education needs to start in kindergarten.”

The researchers conducted seven cross-sectional surveys of children aged 4 to17 years between 1973 and 1996. They conducted five surveys of the same group as young adults aged 18 to 38 years. Participants’ height, weight, blood pressure, cholesterol, and triglycerides were measured every three to four years. During the last six months of 1996, the young adults (71 percent white, 39 percent male, average age 32 years) underwent echocardiography to determine left ventricular mass.

The researchers divided body mass index measurements into quartiles with quartile 1 representing the lowest index and quartile 4, the highest. Increased average levels of left ventricular mass corresponded with increased body mass index quartile as measured in childhood, in adulthood, and as a cumulative burden from childhood to adulthood. Body mass index values from 18.5 to 24.9 are considered normal; BMI from 25 to 29.9 is overweight; and BMI of 30 or greater is obese.

For white men, average index value was 18.1 in childhood and 27.7 in adulthood. For white women, average index was 18.2 in childhood and 26.1 in adulthood. Average index value for black men was 17.7 in childhood and 27.4 in adulthood. For black women, the average was 18.7 in childhood and 29.8 as adults. Average left ventricular mass in adulthood was 30.1 for white men, 31.3 for white women, 32.3 for black men, and 35.9 for black women.

When body mass index was analyzed in quartiles and compared with adult left ventricular mass index, body mass index in the highest quartile in both childhood and adulthood correlated with the largest heart size in young adults.

Xiangrong Li, MD, co-author of the study, said half of the obese adults were also obese as children.

“We need to begin to teach healthy habits in childhood,” said Berenson. “That is one of the major things we have learned from the Bogalusa Heart Study, that heart disease often begins in childhood.”