Obese children appear to have a blood vessel abnormality similar to what doctors see in much older adults with cardiovascular disease, a study has found.
Lead author Kevin Harris, a cardiology fellow at B.C. Children's Hospital, said tests in a group of obese children showed the aorta – the major artery from the heart – had lost normal elasticity, as if the aging process has been accelerated in the blood vessel.
"We were surprised to find that these obese children already have stiff blood vessels," said Dr. Harris. "Aortic stiffness is an early indicator of cardiovascular disease in obese children."
The aorta, the largest artery in the body, carries oxygen-rich blood from the heart to all the other arteries.
"The normal aorta has elastic qualities that buffer the flow of blood. When that elasticity is lost, aortic stiffness results – a sign of developing cardiovascular disease," said Dr. Harris, adding that aortic stiffness in adults is associated with heart attacks and stroke that can result in premature death.
He said the childhood obesity rate has risen dramatically over the last 30 years, leading to predictions that life expectancy in Canada is set to decline for the first time in the country's history.
"I think that underscores the magnitude of the problem," Harris said.
To conduct the study, the B.C. researchers assessed the heart and blood vessels of 63 obese children and 55 normal-weight children using echocardiography, a type of ultrasound. Blood pressure, cholesterol and body mass index also were measured in all the children, who had a mean age of 13.
While the obese children had normal cholesterol levels, their blood pressure was marginally elevated and ultrasounds of the heart showed arterial health was already compromised.
"I think it's kind of an early indicator of cardiovascular disease and it's important because we need to recognize that obesity is affecting children very early on," said Dr. Harris, who was to present his findings Monday at the Canadian Cardiovascular Congress in Montreal.
Toronto cardiologist Dr. Beth Abramson, a spokeswoman for the Heart and Stroke Foundation, said it is alarming to see changes in the performance of the heart and blood vessels in obese children.
She said more than one-quarter of Canadian children aged two to 17 are overweight or obese, putting them at risk for heart disease, high blood pressure and Type 2 diabetes.
"We know there is an association between unhealthy lifestyles and heart disease," Dr. Abramson said. "Poor nutrition and inactivity are threatening their health and well-being. We must rethink the lifestyle standards we have accepted as a society to protect the future health of our kids."
Dr. Harris said the next step for researchers is to determine whether aortic stiffness can be reversed with weight loss through a healthier diet and exercise, using echocardiography as a measuring tool.
"This technique may now be useful for monitoring the progression of arterial disease and vascular health in obese children," he said. "And it also allows us to assess the impact of interventions for obesity that are aiming to improve the health of obese children."
The Canadian Press