Atherosclerosis, Metabolic Syndrome, Visceral Obesity
Conditions
Keywords
Magnetic resonance imaging (MRI), Computed tomography (CT), Visceral obesity, Cardiometabolic risk, Atherosclerosis, Ectopic fat, Carotid plaque
Brief summary
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.
Interventions
None listed
Sponsors
Study design
Eligibility
Inclusion criteria
* Men and women aged 35-65 years
Exclusion criteria
* Massive obesity (BMI ≥ 40 kg/m2) * Pharmacological treatment for lipids, hypertension and/or type 2 diabetes * Clinical signs of cardiovascular disease * Chronic inflammatory or auto-immune diseases * Pulmonary diseases on corticosteroids * Cancers not in remission * History or clinical evidence of coronary heart disease (CHD) * History of revascularisation procedures * Current smoking * Hormonal replacement therapy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in carotid vessel wall volume measured by magnetic resonance imaging (MRI) | Change between baseline and 3-year follow-up | Cross-sectional and longitudinal analyses of the relationships between indices of body fat distribution, visceral adiposity/ectopic fat deposition, cardiorespiratory fitness and non-invasive measurements of macrovascular atherosclerosis |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in abdominal adipose tissue measured by computed tomography (CT) | Change between baseline and 3-year follow-up | Visceral and subcutaneous adipose tissue will be determined at both L2-L3 and L4-L5 levels |
| Change in epi- and pericardial fat measured by magnetic resonance imaging (MRI) | Change between baseline and 3-year follow-up | — |
Countries
Canada