Washington, November 6 : The problems of overweight and heart disease risk factors begin at an early age, and may become evident by the time a child reaches age seven, according to a study.

While making a presentation at the American heart Association’s Scientific Sessions 2007, the researchers revealed that their findings are based on a study of “BMI rebound age”, the age at which BMI reaches its lowest point before increasing through later childhood, adolescence and adulthood.

As many as 308 children—158 boys and 150 girls—were involved in the study, which investigated the subjects BMI rebound age beginning at age 3, and looked at adverse cardiovascular risk effects at age 7.

“Obesity is a problem that develops early in childhood and has adverse cardiovascular consequences early in childhood,” said Dr. Thomas R. Kimball, senior author of the study and professor of paediatrics at the University of Cincinnati College of Medicine in Ohio.

Healthy children entered the study at age 3, and were measured for BMI every four months for the next four years until they reached age 7. The majority of the children, primarily Caucasian, were drawn from the paediatric primary care centre at Cincinnati Children’s Hospital.

The researchers found that earlier BMI rebound age was associated with adverse risk factors for heart disease—such as higher BMI, higher systolic and diastolic blood pressures, higher serum insulin and leptin levels, and higher left ventricular mass and left atrial size—as measured at age 7.

The children were divided into three groups based on age of BMI rebound— below the 25th percentile, between the 25th and 75th percentiles, and above the 75th percentile.

BMI rebound age for children in the 25th percentile was 4.4 years for boys and 4.2 years for girls. In the 75th percentile, the BMI rebound age was 6.6 years for boys and 5.7 years for girls.

“The study implies that girls may have earlier BMI rebound age than boys. Earlier rebound age correlates with greater likelihood to become obese adults, so girls may be more at risk to become obese adults,” Kimball said.

Jennifer Jaworski, lead author of the study and a third-year medical student at the University of Cincinnati College of Medicine in Ohio, said she and her colleagues found statistically significant differences between children in the 25th percentile BMI rebound age and those in the 75th percentile of BMI rebound age.

Kimball stressed the importance of measuring BMI and BMI rebound age in younger children as well as adolescents.

The researcher also said that “these problems of overweight and cardiac risk factors begin at an early age, not just in teenage or adult years. As a physician and parent, I’d rather deal with these issues before the habits are set. The crux of the matter is when these habits are set in childhood, they are difficult to break. It’s not just the child’s problem, but becomes a family issue.” (ANI)