Sometime in the last year or 2 I wrote that, despite my considerable reservations, I had finally come to the conclusion that the American Medical Association’s decision to designate obesity as a disease was appropriate. My rationalization was that the disease label would open more opportunities for funding obesity treatments. However, the explosive growth and popularity of glucagon-like peptide 1 (GLP-1) agonists over the last year has had me rethinking my decision to suppress my long-held reservations about the disease designation.
So, if it’s not a disease, then what should we call it? How do we explain its surge in high-income countries that began in the 1980s? While there are still some folks who see obesity as a character flaw, I think you and I as healthcare providers have difficulty explaining the increase prevalence of obesity as either global breakdown of willpower or a widespread genetic shift as the result of burst of radiation from solar flares.
Dr. William G. Wilkoff
However, if we want to continue our search and finger-pointing we need to have a better definition of exactly what obesity is. If we’re going to continue calling it a disease we have done a pretty sloppy job of creating diagnostic criteria. To be honest, we aren’t doing such a hot job with “long COVID” either.
A recent article in the New York Times makes it clear that I’m not the only physician who is feeling uncomfortable with this lack of diagnostic specificity.
We know that using body mass index (BMI) as a criteria is imprecise. There are healthy individuals with elevated BMIs and there are others who are carrying an unhealthy amount of fat who have normal BMIs. And, there are individuals who have what might appear to be an excess amount of fat who are fit and healthy by other criteria.
Some investigators feel that a set of measurements that includes a waist and/or hip measurement may be a more accurate way of determining visceral adipose tissue. However, this body roundness index (BRI) currently relies on a tape measurement. Until the technique can be preformed by an inexpensive and readily available scanner, the BRI cannot be considered a practical tool for determining obesity.
Dr. Francisco Rubino, the chair of metabolic and bariatric surgery at Kings College in London, England, has been quoted as saying that, “if one defines a disease inaccurately, everything that stems from that – from diagnosis to treatment to policies – will be distorted and biased.”
Denmark has been forced to relabel obesity as a risk factor because the disease designation was stressing the financial viability of their healthcare system as more and more patients were being prescribe GLP-1 agonists, sometimes off label. A rationing strategy was resulting in suboptimal treatment of a significant portion of the obese population.
Spearheaded by Dr. Rubino, a Lancet Commission composed of physicians has tasked itself to define an “evidence-based diagnosis for obesity. Instead of relying on a single metric such as the BMI or BRI, diagnosing “clinical obesity” would involve a broad array of observations including a history, physical examination, standard laboratory and additional testing, “naming signs and symptoms, organ by organ, tissue by tissue, with plausible mechanisms for each one.” In other words, treating each patient as an individual using evidence-based criteria to make a diagnosis. While likely to be time consuming, this strategy feels like a more scientific approach. I suspect once clinical obesity is more rigorously defined it could be divided into several subtypes. For example, there would be a few conditions that were genetic; Prader-Willi syndrome being the best known.
However, I think the Lancet Commission’s strategy will find that the majority of individuals who make up this half-century global surge have become clinically obese because they have been unable to adapt to the obeseogenic forces in our society, which include diet, autocentricity, and attractive sedentary forms of entertainment, to name just three.
In some cases these unfortunate individuals are more vulnerable because there were born into an economically disadvantaged situation. In other scenarios a lack of foresight and/or political will may have left individuals with no other choice but to rely on automobiles to get around. Still others may find themselves living in a nutritional desert because all of the grocery stores have closed.
I recently encountered a descriptor in a story about the Federal Emergency Management Agency which could easily be adapted to describe this large and growing subtype of individuals with clinical obesity. “Social vulnerability” is measure of how well a community can withstand external stressors that impact human health. For example, the emergency management folks are thinking in terms of natural disaster such as hurricanes, floods, and tornadoes and are asking how well a given community can meet the challenges one would create.
But, the term social vulnerability can easily be applied to individuals living in a society in which unhealthy food is abundant, an infrastructure that discourages or outright prevents non-motorized travel, and the temptation of sedentary entertainment options is unavoidable. Fortunately, not every citizen living in an obesogenic society becomes obese. What factors have protected the non-obese individuals from these obeseogenic stressors? What are the characteristics of the unfortunate “vulnerables” living in the same society who end up being obese?
It is time to shift our focus away from a poorly defined disease model to one in which we begin looking at our society to find out why we have so many socially vulnerable individuals. The toll of obesity as it is currently defined is many order of magnitudes greater than any natural disaster. We have become communities that can no longer withstand the its obesogenic stressors many of which we have created and/or allowed to accumulate over the last century.
Dr. Wilkoff practiced primary care pediatrics in Brunswick, Maine, for nearly 40 years. He has authored several books on behavioral pediatrics, including “How to Say No to Your Toddler.” Other than a Littman stethoscope he accepted as a first-year medical student in 1966, Dr. Wilkoff reports having nothing to disclose. Email him at pdnews@mdedge.com.