Waist Size Weighs on Blood Pressure and Insulin

Waist circumference may be an underappreciated risk factor for disease anddeath, and is more of a red flag than blood pressure, insulin sensitivity, orobesity as measured by body mass index (BMI), according to a group ofresearchers reporting an analysis of the Quebec Health Survey in the March2005 issue of Hypertension.

Paul Poirier, MD, PhD, and colleagues at Laval Hospital Research Centerlooked at a sampling of the massive health survey, which included more than 5million of the 6.7 million residents of the province of Quebec, essentiallythe entire adult population. The sampling included 907 men and 937 women,ranging from 17 to 74 years of age.

Researchers had data on fasting glucose, insulin, and lipid levels, amongother laboratory values, and measurements of height and weight for calculatingBMI, as well as waist circumference. Participants' BMIs ranged from 16.7 to46.9, with an average of about 25 for both sexes. Men had an average waistcircumference of 89 cm (35 in), while women averaged 77.3 cm (30.5in).

Significant associations were noted among BMI, waist circumference, fastinginsulin, and blood pressure. According to the researchers, the associationamong risk factors can be explained by variation in the amount of abdominalfat, as estimated by waist circumference.

The effect of waist circumference was stronger than that of any otherfactor, according to the group. For example, when participants were sorted byBMI, those with more abdominal fat—and a larger waist size than otherswith the same BMI—also tended to have higher blood pressure.

Central obesity is an important common link between blood pressure, insulinresistance, and other unbalanced health indicators. Fortunately, clinicianscan easily keep track of this key health risk factor with a tape measure.