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Impact Of Changing Obesity Definition on Prevalence

The second item on the disease definition modification checklist developed by the Guidelines International Network (G-I-N) Preventing Overdiagnosis Working Group published in JAMA Internal Medicine,  pertains to the issue of how a proposed new definition would alter the prevalence of the disease.

As indicated in the name of the working group that came up with this checklist, their primary concern is over-diagnosis or “diagnosis-creep”, as often disease modifications tend to increase the number of people covered under said new diagnosis.

So what is the implication for prevalence of obesity if we move from a definition based on BMI to one based on an actual impairment of health?

Fortunately, we have some data on this, including our own studies on the Edmonton Obesity Staging System, which ranks individuals based on the presence of obesity related impairments in mental, physical, and/or functional health.

Based on varying estimates, anywhere between 5-15% of individuals with a BMI over 30 would be considered to be rather healthy with no or minimal health risks. These people would need to be excluded, if obesity was defined as the presence of abnormal or excess body fat that impairs health (they may at best be considered to have “pre-obesity”). This would slightly reduce the number of people considered to have obesity (especially in the BMI 30-35 range).

On the other hand, an estimated 40-50% of individuals in the BMI 25-30 range, would actually have significant health problems at least in part attributable to their excess weight, and these individuals may potentially benefit from obesity treatments. Thus, such a change in definition would very substantially increase the number of individuals considered to have obesity.

This, of course is something that needs to be carefully considered, as it would clearly have implications for obesity treatment in a significant number of individuals, who at this time would not meet the criteria for obesity management.

Let us, however, remember that one would still need to demonstrate significant benefit of treatment in these newly classified individuals. before expanding the indication of existing obesity treatments to these individuals.

@DrSharma
Edmonton, AB

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A Checklist For Modifying Disease Defnitions

At the recent European Congress on Obesity in Porto, Portugal, there was much support for calling obesity a chronic progressive relapsing disease.

However, there was also much agreement that the current criteria for diagnosing this disease, based on BMI criteria alone, has important limitations in that it may over-diagnose a significant number of individuals at no or very little imminent risk from their body fat and (even more importantly) under-diagnose a substantial number of individuals, who may well stand to benefit from anti-obesity treatments.

Thus, as my readers are well aware, I have long called for a redefinition of obesity based on the actual presence of health impairments attributable to abnormal or excess body fat.

It is thus timely that JAMA Internal Medicine has just published a seminal article by Jenny Doust and colleagues on behalf of the Guidelines International Network (G-I-N) Preventing Overdiagnosis Working Group, that provides a framework for anyone proposing changes to disease definitions.

Using a 5-step process that included (1) a literature review of issues, (2) a draft outline document, (3) a Delphi process of feedback on the list of issues, (4) a 1-day face-to-face meeting, and (5) further refinement, the group developed an 8-item checklist of items to consider when changing disease definitions.

The checklist specifically deals with the issues of definition changes, number of people affected, trigger, prognostic ability, disease definition precision and accuracy, potential benefits, potential harms, and the balance between potential harms and benefits.

The authors propose that,

“…the checklist be piloted and validated by groups developing new guidelines. We anticipate that the use of the checklist will be a first step to guidance and better documentation of definition changes prior to introducing modified disease definitions.”

No doubt it would be prudent to consider all of the identified aspects in the checklist, when considering changing the definition of obesity from one based simply on BMI to a more clinical definition, based on actual impairments in health.

In coming posts, I will consider each of the proposed checklist items and how they may apply to such a change in the definition of obesity.

@DrSharma
Edmonton, AB

Hat tip to Dr. Marcela Flores for drawing my attention to this paper

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Why Would Anyone Want Access to Prescription Medications For Obesity?

Just imagine if the question in the title of this post was, “Why would anyone want access to prescription medications for diabetes?” (or heart disease? or lung disease? or arthritis? or, for that matter, cancer?)

Why would anyone even ask that question?

If there is one thing we know for sure about obesity, it is that it behaves just like every other chronic disease.

Once you have it (no matter how or why you got it) – it pretty much becomes a life-long problem. Our bodies are so efficient in defending our body fat, that no matter what diet or exercise program you go on, ultimately, the body wins out and puts the weight back on.

In those few instances where people claim to have “conquered” obesity, you can virtually bet on it, that they are still dealing with keeping the lost weight off every single day of their life – they are not cured, they are just treated! Their risk of putting the weight back on (recidivism) is virtually 100% – it’s usually just a matter of time.

Funnily enough, this is no different from people trying to control any other chronic disease with diet and exercise alone.

Take for e.g. diabetes. It is not that diet and exercise don’t work for diabetes, but the idea that most people can somehow control their diabetes with diet and exercise alone is simply not true. No matter what diet they go on or what exercise program they follow, sooner or later, their blood sugar levels go back up and the problems come back.

You could pretty much say the same for high blood pressure or cholesterol, or pretty much any other chronic health problem (that, in fact, is the very definition of “chronic”).

So why medications for obesity?

Because, like every other chronic disease, medications can help patients achieve long-term treatment goals (of course only as long as they stay on treatment).

Simply put, if the reason people virtually always regain their lost weight (no matter how hard they try to lose it) is simply because of their body’s ability to resist weight loss and promote weight regain, then medications that interfere with the body’s ability to resist weight loss and promote weight regain, will surely make it far more likely for them to not only lose the weight but also keep it off.

Now that we increasingly understand many of the body’s mechanisms to defend against weight loss and promote weight regain (and the body has a whole bag of tricks that you are up against), then pharmacologically blocking these mechanisms makes this a manageable (fair?) fight.

This is by no means easy. Interfering with human physiology always comes at a cost – which is why we need medications that are robustly tested for safety and efficacy (which is why we are here talking about prescription medications and not the nonsense you can buy over the counter in your local drug store or health supplement outlet).

There is of course no guarantee that any one medication will work for or be tolerated by everyone – again, no different from the medications for other chronic diseases (which is why we have so many of them for the same indication).

So who has access to prescription anti-obesity medications in Canada?

Short answer – almost no one.

Thus, in the  2017 Report Card on Access To Obesity Treatment For Adults, released last week at the 5th Canadian Obesity Summit, the less than 20% of Canadians living with obesity (and that is a very generous estimate) have access to the two prescriptions medications approved by Health Canada for long-term treatment of obesity.

Thus, as far a coverage for obesity medications in Canada is concerned,

Neither anti-obesity medication (Xenical® or saxenda®) are listed as a benefit on any provincial/territorial formulary and, therefore, they are not covered under any provincial public drug benefit (or pharmacare) programs.

There may be special-access programs in some provinces that adjudicate coverage for non-formulary medications based on individual case review; however, coverage for anti-obesity medications through these programs are not guaranteed and are, in fact, rare.

Anti-obesity medications are not covered in any federal public drug benefit programs.

Again one must ask, what will it take for governments, employers, and payers to stop discriminating against Canadians living with obesity in our healthcare system?

@DrSharma
Edmonton, AB

Disclaimer: I have received honoraria for speaking and consulting for companies that make anti-obesity medications

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Canadians Have Virtually No Access To Interdisciplinary Obesity Care

Every single guideline on obesity management emphasises the importance of interdisciplinary obesity management by a team that not only consists of a physician and a dietitian but also includes psychologists, exercise specialists, social workers, and other health professionals as deemed necessary.

As is evident from the evident from the 2017 Report Card on Access To Obesity Treatment For Adults, released last week at the 5th Canadian Obesity Summit, the overwhelming majority of Canadians living with obesity have no access to anything that even comes close.

Thus, the report finds that

Among the health services provided at the primary care level for obesity management, dietitian services are most commonly available.

Access to exercise professionals, such as exercise physiologists and kinesiologists, at the primary care level is limited throughout Canada.

Access to mental health support and cognitive behavioural therapy for obesity management at the primary care level is also limited throughout Canada. bariatric surgery programs often have a psychologist or a social worker that offers mental health support and cognitive behavioural therapy to patients on the bariatric surgery route, but the availability of these supports outside of these programs is scarce.

Centres where bariatric surgery is conducted also have inter- disciplinary teams that work within the bariatric surgical programs and provide support for patients on the surgical route.

Alberta and ontario have provincial programs with dedicated bariatric specialty clinics that offer physician-supervised medical programs with interdisciplinary teams for obesity management.

Interdisciplinary teams for obesity management outside of the bariatric surgical programs are available in one out of five regional health authorities (RHa) in british Columbia, one out of 18 RHas in Québec, one out of two RHas in new brunswick and one out of four RHas in newfoundland and labrador.

Among the territories, only yukon has a program with an interdisciplinary team focusing on obesity management in adults.

I hardly need to remind readers, that this is in stark contrast to the resources and teams available to patients with diabetes, heart disease, lung disease, or any other common chronic disease, that are regularly available in virtually every health jurisdiction across the country (not to say that they are perfect or sufficient – but at least there is some level of service available).

I understand that our current obesity treatments are extremely limited (at least when effectiveness is measured in terms of weight loss). But even if access to these resources could simply help stabilise and prevent further weight gain (progression) and perhaps improve overall health and well-being, surely Canadians living with obesity should deserve no less that people living with any other chronic disease.

There is simply no excuse for treating Canadians living with obesity as second-class citizens in our publicly funded healthcare system.

@DrSharma
Edmonton, AB

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Another Canadian Obesity Summit Exceeds Expectations

Wow, what a week!

Just back from the 5th Canadian Obesity Summit, there is no doubt that this summit will live long in the minds (and hearts) of the over 500 attendees from across Canada and beyond.

As anyone would have appreciated, the future of obesity research, prevention and practice is alive and kicking in Canada. The over 50 plenary review lectures as well as the over 200 original presentations spanning basic cellular and animal research to health policy and obesity management displayed the gamut and extent of cutting-edge obesity research in Canada.

But, the conference also saw the release of the 2017 Report Card on Access to Obesity Treatment for Adults, which paints a dire picture of treatment access for the over 6,000,000 Canadians living with this chronic disease. The Report Card highlights the virtually non-existant access to multidisciplinary obesity care, medically supervised diets, or prescription drugs for the vast majority of Canadians.

Moreover, the Report Card reveals the shocking inequalities in access to bariatric surgery between provinces. Merely crossing the border from Alberta to Saskatchewan and your chances of bariatric surgery drops from 1 in 300 to 1 in 800 per year (for eligible patients). Sadly, numbers in both provinces are a far cry from access in Quebec (1 in 90), the only province to not get an F in the access to bariatric surgery category.

The presence of patient champions representing the Canadian Obesity Network’s Public Engagement Committee, who bravely told their stories to a spell-bound audience (often moved to tears) at the beginning of each plenary session provided a wake up call to all involved that we are talking about the real lives of real people, who are as deserving of respectful and effective medical care for their chronic disease as Canadians living with any other chronic disease.

Indeed, the clear and virtually unanimous acceptance of obesity as a chronic medical disease at the Summit likely bodes well for Canadians, who can now perhaps hope for better access to obesity care in the foreseeable future.

Thanks again to the Canadian Obesity Network for hosting such a spectacular event (in spectacular settings).

More on some of the topics discussed at the Summit in coming posts.

For an overview of the Summit Program click here

@DrSharma
Edmonton, AB

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