High BMI in young people can change the structure of the heart

Because of these changes, young people who are overweight may be more prone to heart diseases as they grow older

Being overweight in youth can cause hard to reverse structural changes in the heart that can predipose to heart diseases in later life.

High Body Mass Index (BMI) in young people can cause higher blood pressure and thicken heart muscle, according to new research in the American Heart Association’s journal Circulation.

The study is the first to explore if higher body mass index (BMI) – a weight-for-height index – results in adverse effects on the cardiovascular system in young adults. While observational studies can suggest associations between risk factors or lifestyle behaviors and heart disease, they cannot prove cause-and-effect. Here, investigators triangulated findings from three different types of genetic analysis to uncover evidence that BMI causes specific differences in cardiovascular measurements.

“Thickening of vessel walls is widely considered to be the first sign of atherosclerosis, a disease in which fatty plaques build up within the arteries and lead to heart disease.”

“Our results support efforts to reduce body mass index to within a normal, healthy range from a young age to prevent later heart disease,” said Kaitlin H. Wade, B.Sc., Ph.D., lead author of the study and a research associate at the Medical Research Council Integrative Epidemiology Unit at the University of Bristol Medical School in the United Kingdom.

Researchers used data on several thousand healthy 17-year-olds and 21-year-olds who have participated in the ongoing Children of the 90s study (also known as the Avon Longitudinal Study of Parents and Children) since they were born in the Bristol area of the United Kingdom.

The findings suggest that higher BMI:

• caused higher systolic (top number) and diastolic (bottom number) blood pressure; and
• caused enlargement of the left ventricle, the heart’s main pumping chamber.

“Thickening of vessel walls is widely considered to be the first sign of atherosclerosis, a disease in which fatty plaques build up within the arteries and lead to heart disease. However, our findings suggest that higher BMIs cause changes in the heart structure of the young that may precede changes in blood vessels,” Wade said.