https://www.medpagetoday.com/Endocr...id=nl_mpt_DHE_2017-03-29&eun=g790893d0r&pos=1
Medpagetoday
Endocrinology
Time to Redefine Obesity?
Experts: if it's a disease, it needs to be about more than body fat measure
Canadian experts proposed a small tweak to the definition of obesity that would have big implications for the way it is diagnosed.
The long-standing World Health Organization definition of "abnormal or excessive fat accumulation that may impair health" should be changed to the less equivocal "abnormal or excessive fat accumulation that impairs health," said Arya Sharma, MD, PhD, and Denise Campbell-Scherer, MD, PhD, both of the University of Alberta in Edmonton.
"This change in wording, albeit minor, would, in fact, change the whole nature of the discussion. The defining criterion for whether a given individual has the 'disease' now is not whether that person has excessive body fat or even whether that fat is 'abnormal,' but rather whether abnormal or excessive body fat is actually impairing that person's health," Sharma and Campbell-Scherer said in the journal Obesity.
One of the first implications of the new definition would be that body-mass index (BMI), which has always been an imprecise measure, would no longer be used to diagnose obesity. "This is not to say that BMI would no longer serve as a practical screening tool to help identify people at risk for obesity -- but it would no longer be considered 'diagnostic' or the defining characteristic of this disease. It would, in fact, take more than a scale or a measuring tape to diagnose obesity," the experts said.
Another implication of the new definitions is that healthcare professionals would no longer misdiagnose those who are "fat but fit" -- individuals for whom weight loss would provide little proven benefit. Similarly, the new definition would not miss those who are "thin but metabolically obese" -- individuals with a relatively small amount of belly fat that is nevertheless negatively impacting their health, Sharma and Campbell-Scherer said.
Furthermore, doctors would no longer have to debate whether or not a mixed-race individual meets the BMI criteria for one race or the other or how to diagnose obesity in populations in which there are no established validated BMI cutoffs, they said.
"In clinical practice, assessing whether or not abnormal or excess weight is impairing someone's health should not pose a major diagnostic dilemma. In the vast majority of patients, a few interview questions, a brief physical exam, and a short panel of routine lab tests should readily establish (or rule out) the diagnosis of obesity," the experts said.
Some might argue the new approach would be impractical, but such diagnostic approaches are standard practice for many other diseases that require a clinical encounter, laboratory testing, and/or diagnostic imaging for their diagnosis. "In fact, there are very few diseases that can be reliably diagnosed with just a single measure or test," Sharma and Campbell-Scherer argued.
Of course, there would be borderline cases in which the signs and symptoms are too vague or too subjective to be diagnostic, they said, but it is the same with other diseases in which borderline cases may require a more intense work-up or simply a watch-and-wait approach.
In an accompanying editorial, two U.S. experts approved of the new definition with one caveat. Donna Ryan, MD, and Eric Ravussin, PhD, both of the Pennington Biomedical Research Center in Baton Rouge, La., said, "Even if it is not a totally novel idea, we fully agree that BMI should not be the only criteria for a diagnosis of obesity in the clinic. But BMI categories have utility on a population basis and for screening. Let's not throw out the baby with the bathwater."
"By this we mean, don't discard use of BMI altogether just because it's not completely diagnostic of the disease," they said.
Sharma disclosed financial relationships with Novo Nordisk and Takeda. Campbell-Scherer disclosed a financial relationship with Novo Nordisk. Ryan and Ravussin disclosed no financial relationships.
Medpagetoday
Endocrinology
Time to Redefine Obesity?
Experts: if it's a disease, it needs to be about more than body fat measure
- by Jeff Minerd
Contributing Writer, MedPage TodayMarch 28, 2017 - This article is a collaboration between MedPage Today® and:
Canadian experts proposed a small tweak to the definition of obesity that would have big implications for the way it is diagnosed.
The long-standing World Health Organization definition of "abnormal or excessive fat accumulation that may impair health" should be changed to the less equivocal "abnormal or excessive fat accumulation that impairs health," said Arya Sharma, MD, PhD, and Denise Campbell-Scherer, MD, PhD, both of the University of Alberta in Edmonton.
"This change in wording, albeit minor, would, in fact, change the whole nature of the discussion. The defining criterion for whether a given individual has the 'disease' now is not whether that person has excessive body fat or even whether that fat is 'abnormal,' but rather whether abnormal or excessive body fat is actually impairing that person's health," Sharma and Campbell-Scherer said in the journal Obesity.
One of the first implications of the new definition would be that body-mass index (BMI), which has always been an imprecise measure, would no longer be used to diagnose obesity. "This is not to say that BMI would no longer serve as a practical screening tool to help identify people at risk for obesity -- but it would no longer be considered 'diagnostic' or the defining characteristic of this disease. It would, in fact, take more than a scale or a measuring tape to diagnose obesity," the experts said.
Another implication of the new definitions is that healthcare professionals would no longer misdiagnose those who are "fat but fit" -- individuals for whom weight loss would provide little proven benefit. Similarly, the new definition would not miss those who are "thin but metabolically obese" -- individuals with a relatively small amount of belly fat that is nevertheless negatively impacting their health, Sharma and Campbell-Scherer said.
Furthermore, doctors would no longer have to debate whether or not a mixed-race individual meets the BMI criteria for one race or the other or how to diagnose obesity in populations in which there are no established validated BMI cutoffs, they said.
"In clinical practice, assessing whether or not abnormal or excess weight is impairing someone's health should not pose a major diagnostic dilemma. In the vast majority of patients, a few interview questions, a brief physical exam, and a short panel of routine lab tests should readily establish (or rule out) the diagnosis of obesity," the experts said.
Some might argue the new approach would be impractical, but such diagnostic approaches are standard practice for many other diseases that require a clinical encounter, laboratory testing, and/or diagnostic imaging for their diagnosis. "In fact, there are very few diseases that can be reliably diagnosed with just a single measure or test," Sharma and Campbell-Scherer argued.
Of course, there would be borderline cases in which the signs and symptoms are too vague or too subjective to be diagnostic, they said, but it is the same with other diseases in which borderline cases may require a more intense work-up or simply a watch-and-wait approach.
In an accompanying editorial, two U.S. experts approved of the new definition with one caveat. Donna Ryan, MD, and Eric Ravussin, PhD, both of the Pennington Biomedical Research Center in Baton Rouge, La., said, "Even if it is not a totally novel idea, we fully agree that BMI should not be the only criteria for a diagnosis of obesity in the clinic. But BMI categories have utility on a population basis and for screening. Let's not throw out the baby with the bathwater."
"By this we mean, don't discard use of BMI altogether just because it's not completely diagnostic of the disease," they said.
Sharma disclosed financial relationships with Novo Nordisk and Takeda. Campbell-Scherer disclosed a financial relationship with Novo Nordisk. Ryan and Ravussin disclosed no financial relationships.
