Inspiring My Interest in Visceral FatWednesday, July 11, 2012
Clearly one of the most prominent researchers, who has championed the measurement of waist circumference as a screening tool for abdominal obesity, is my friend and colleague Jean-Pierre Després from Laval University.
He is also the organiser and host of this 3rd International Congress on Abdominal Obesity.
In his plenary talk at the beginning of the congress, Despres presented the results of the INSPIRE ME IAA Study (which stands for INternational Study of Prediction of Intra‐Abdominal Adiposity and its Relationships with CardioMEtabolic Risk/Intra‐ Abdominal Adiposity).
INSPIRE ME IAA is the largest, standardised international imaging study ever conducted on abdominal obesity as a risk factor for cardiovascular disease and type 2 diabetes. In total, 297 physicians recruited 4504 patients (53% men, aged 39‐71 years) from 29 countries with a planned 3‐ year follow‐up.
Cardiometabolic risk variables were assessed at baseline and at follow‐up as well as measurements of VAT, abdominal subcutaneous adipose tissue and liver attenuation (inversely related to liver fat) by computed tomography (at baseline only).
In this study, not only was increased levels of visceral adipose tissue (VAT) associated with a remarkably increased risk of type 2 diabetes, but was also independently associated with an increasingly deleterious plasma lipid/lipoprotein profile, with higher apoB and triglycerides and lower HDL cholesterol
and higher levels of circulating inflammatory markers.
Regardless of the presence of type 2 diabetes, increased VAT was associated with the presence of cardiovascular disease.
Despite a strong correlation between the BMI and waist circumference, there was considerable variability of waist circumference measures within each single BMI unit.
In the 3-year follow-up, which included about 2000 non-diabetic individuals, about 200 participants converted to type 2 diabetes, and it is perhaps no surprise that these individuals all tended to have greater levels of VAT and liver fat.
For clinicians this means that individuals with increased VAT are far more likely to have Stage 2 or Stage 3 obesity than those without VAT – at least at BMI’s less than 40, measuring waist circumference may represent a quick screening tool (which is why waist circumference measurements are included in the Assess step of the 5As of Obesity Management™).
These findings of course are very much in line with our previous findings in 27,000 individuals in the INTERHEART study, where waist-to-hip ratio was a far better predictor of cardiovascular risk than BMI.
The take away is that when it comes to the impact of body fat on metabolic health, it all comes down to location, location, location!
Québec City, Québec