A study of 40 overweight children in Edmonton has revealed they all share something in common aside from being heavy: each one of them has high levels of apoB48, a structural protein found in intestinal cholesterol.
The children displayed high levels of apoB48 even as their LDL cholesterol levels, which are typically high in overweight adults, remained in the normal range.
In discovering high levels of apoB48 in these children, the researchers believe they've found a new and important clue to better understand how some adults are more susceptible to cardiovascular disease (CVD) than others.
"We don't consider these children to be at risk of developing CVD right now. But they have indicated apoB48 at levels that are the same as those that appear in adults who are considered at high risk; so, unless their levels decrease, they will become high risk as they age," said Dr. Spencer Proctor, a nutritional scientist at the U of A and a co-author of the study.
However, testing for apoB48 is currently rare, difficult and expensive, Proctor said.
The prevailing wisdom among researchers is that high LDL cholesterol, which is produced in the liver, is the best indicator of a patient's CVD risk, even though researchers struggle to explain why 40 to 50 per cent of people who suffer cardiac episodes have "normal" LDL levels.
Proctor and his colleagues, including U of A obesity researcher Dr. Geoff Ball, believe that apoB48, which is found exclusively in a type of cholesterol produced in the intestine called chylomicrons, may complement LDL cholesterol as a marker that doctors should look for when gauging a patient's risk of developing CVD.
"We are not measuring the right things and not understanding all the processes that cause CVD," Proctor said. "This study adds to a growing body of evidence we've collected that indicates measuring apoB48 levels as a means to measure chylomicron levels may be an importa
Contact: Ryan Smith
University of Alberta