A new study has shown that combining 2 ways of assessing a person’s size —body mass index (BMI) and waist-to-height ratio (WHtR) —may be a better way of identifying which overweight and obese individuals are at highest risk for cardiovascular disease and diabetes than either measurement alone.

The work was reported at the 2014 European Congress on Obesity by Seán Millar, PhD, an epidemiologist at University College Cork, Ireland. Dr. Millar said that the concept of being obese and “metabolically healthy” is a controversial idea at a population level, “and we would never advocate that any level of obesity is necessarily healthy or okay.”

But “at a clinical level, we have to acknowledge that a high proportion of subjects who are overweight or obese will not develop cardiometabolic outcomes, so we are looking for tools to identify the people who will. “If the prevalence of obesity in our population is high, we run the risk of just classifying everyone as being at risk, so we’re looking to narrow it down,” he added.

‘Is the waist-to-height ratio greater than 0.5?’ is the easiest, quickest screening tool you can have, and it works for everybody in the world, and it’s particularly useful for children. Also, eliminating BMI from the equation will make the assessment quicker and easier for doctors, as they won’t have to weigh people. Nevertheless, many people are wedded to BMI, so it’s better to add WHtR. BMI is the traditionally assessed surrogate measure of adiposity, “but there are certain limitations with this. It’s a weight-to-height measure that cannot distinguish between fat and lean mass, and numerous studies have suggested that obesity characterization based on BMI is inadequate and may misclassify adiposity”, Dr. Millar said.

Other research has shown that central obesity is more important, and this is often measured by waist circumference, he said, but the latter “doesn’t take whole body fat distribution into account.”

from Medscape Medical News, June 2, 2014