Young, apparently healthy -- and at risk of heart disease

Atherosclerosis – or buildup of fat in the walls of arteries − is thought of as a disorder of older people but it affects a large number of young men and women, according to a new Heart and Stroke Foundation study.

"The proportion of young, apparently healthy adults who are presumably 'the picture of health' who already have atherosclerosis is staggering," says Dr. Eric Larose, an interventional cardiologist at the Institut universitaire de cardiologie et de pneumologie de Québec and an assistant professor at Université Laval.

Atherosclerosis can eventually lead to serious problems including heart disease, stroke, or even death.

The study enrolled 168 young adults (age 18 to 35) – half male and half female – who had no known cardiovascular disease or risk factors such as family history of premature heart disease, diabetes, smoking, high blood cholesterol, or high blood pressure.

The team took complete body measurements, including height, weight, body-mass index and waist circumference. They also measured, through magnetic resonance imaging (MRI), various body fat deposits including subcutaneous fat (fat under the skin that you can measure with calipers) as well as fat within and around the abdomen and chest including the amount of intra-abdominal or visceral fat. Ultimately, they measured atherosclerosis volumes of the carotid arteries by MRI.

The researchers found that although a large proportion of subjects didn't have traditional risk factors for atherosclerosis, they did have discrete signs: greater waist circumference, and visceral fat covering the internal organs within the chest and abdomen. Visceral fat is difficult to detect because it surrounds the organs deep inside the body, unlike the fat under our skin than can be easily detected in the mirror or with a pinch of the fingers.

"We know obesity is a bad thing," says Dr. Larose "but we're dropping the ball on a large proportion of young adults who don't meet traditional measures of obesity such as weight and BMI."

He says their message is that beyond simple weight and BMI, measures of fat hidden within (visceral fat) are greater predictors of atherosclerosis. The people with greater visceral fat will have greater atherosclerosis, even if they are young and apparently healthy − and could benefit from preventive lifestyle measures.

Dr. Larose adds that despite having normal weight and BMI, young adults with greater visceral fat have greater atherosclerosis burden, therefore greater risk for clinical events including heart attack and stroke in the long run. "We were encouraged to find that in this young and apparently healthy population, an easy way to measure risk in the doctor's office is through waist circumference," he says.

At any given BMI, an enlarged waist circumference measured with a simple tailor's ribbon was predictive of increased visceral adiposity and of premature atherosclerosis. The prediction of visceral adiposity and of atherosclerosis was almost as precise as by MRI.