Visceral Obesity/Ectopic Fat and Non-invasive Markers of Atherosclerosis: A Cardiometabolic-cardiovascular Imaging Study

Although it is frequently mentioned in the media that overweight and obesity have reached epidemic proportions worldwide and in this country, some Canadians are perplexed and sometimes confused about the role of obesity in diabetes and heart disease. In fact, the investigators even hear from time to time that there could be "healthy" obese individuals. In clinical practice, assessment of obesity as a risk factor for cardiovascular disease (CVD) remains a challenge as even some physicians are confused. However, studies conducted in our laboratory and by other research teams around the world over the last 20 years have clearly shown that body shape is more important than body size when evaluating the risk of overweight/obesity and that high accumulation of abdominal fat (excess belly fat) increases the risk of diabetes and cardiovascular disease (CVD).

The investigators now need to better understand the link between excess belly fat and atherosclerosis (the thickening of artery walls by fatty deposits, also referred to as atherosclerotic plaque), leading to complications such as angina (chest pain) and myocardial infarction (heart attacks). Using non-invasive imaging techniques such as magnetic resonance imaging, the investigators therefore propose to examine the relationships between measures of fatness and of abdominal fat and the size of atherosclerotic plaque in large blood vessels of apparently healthy human subjects. This study is also a unique opportunity to look, for the first time, at the relationship between belly fat, blood sugar, several well-known risk factors for heart disease (cholesterol, blood pressure, cardiorespiratory fitness, etc.) and the size of atherosclerotic plaques. This research program should pave the way to the development of new improved preventive/therapeutic approaches focusing not on body weight but rather on abdominal fat and associated blood abnormalities which are predictive of the development of atherosclerotic plaques leading to the premature development of heart disease.