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The History of “Essential” Hypertension Has Much To Teach Us About Obesity

I spent the first 10 years of my professional life studying and treating hypertension. As a bit of a history buff, I dug out old books on hypertension and went back to reading papers on blood pressure that were written in the 20s and 30s. I also had numerous mentors, who were around well before the advent of modern diagnostics or pharmacotherapy. In retrospect, I believe that there is much we can learn from the history of hypertension.

In the early part of last century, as we learnt more about the physiology of blood pressure regulation, numerous forms of “secondary” hypertension were identified (e.g. renal artery stenosis, Conn’s Syndrome, pheochromocytoma, etc.). Although these were rare conditions, they taught us much about pathophysiology – but (to this day), most case of elevated blood pressure are still considered “essential”, meaning that they do not appear to have a defined cause (genetics and environment both play a big role but the details remain rather murky).

Although the link between elevated blood pressure, stroke, heart disease, and kidney failure were well-recognised, there were no good treatments. In fact, the history of medical and surgical treatment of hypertension during the first part of the 1900s was so dismal, that many were opposed to treating hypertension with anything other than a highly restricted low-salt diet. Prior to the 1950s, pharmacotherapy included drugs like sodium thiocyanate, barbiturates, bismuth, bromides, hexamethonium, hydralazine, or reserpine – drugs that were poorly tolerated and for which there was little evidence that they lowered mortality. In desperate cases, surgeons performed sympathectomies – a drastic and complex operation.

Given the dismal landscape of medication for hypertension, there were loud voices that challenged the whole concept of hypertension. After all, if there were no good treatments, would it not be best to leave the patients alone and perhaps just support them in other ways? There were prominent doctors who warned about the possible damage that lowering blood pressure could do (particularly to the elderly). Even those who supported treatment, suggested modest targets – 170/110 mmHh was deemed “not so bad”.

Then came the 50s. The first modern drug to be introduced was the oral-diuretic chlorothiazide. Then came, beta-blockers, ca-antagonists, ACE-inhibitors, ARBs, and renin blockers.

Now that effective medications were available, researchers could conduct long-term studies to prove that these medications were not only safe and effective in lowering blood pressure, but could actually drastically reduce the incidence of strokes, heart attacks, and kidney failure.

But even as these studies were ongoing, there were the “nay” sayers. People who pointed out that, given the dismal history of hypertension medications, these should have no place in the clinic. People, who, even if they conceded that the medications were more effective and safer that ever before, pointed out that there was not enough data to support their routine use. There were those, who warned against lowering blood pressure too far and those who decidedly did not consider elevated blood pressures in the elderly a worthwhile target. And of course, there continued to be those that felt that rather than trying to treat hypertension, we should focus all efforts on preventing it by declaring a war on salt.

How things have changed. Today, no doctor would think twice about prescribing anti-hypertensive medications to a patient with elevated blood pressure. No payer would refuse the coverage of anti-hypertensive medications. No medical student leaves medical school without training in hypertension management. In fact, the only excuse today for anyone walking around with elevated blood pressure is either that they have not been diagnosed or are not taking their medications as prescribed (of course there are still some patients for whom the existing treatments are not tolerated or do not work, but these are few and far between).

I still recall the debates at conferences (my first hypertension conference was the World Hypertension Conference in Kyoto in 1988) on whether or not hypertension is a disease or just a risk factor. I recall proponents suggesting that simply improving lifestyles (without lowering blood pressures) would be as useful if not better for patients than exposing them to life-long pharmacotherapy (after all essential hypertension is just a “lifestyle” disease). I remember arguments about definitions and targets, about diagnostic strategies and therapeutic pathways (e.g. is it better to increase the dose, switch, or add-on?).

Funnily enough, I am reliving much of this history with obesity. There are those who, given the dismal past of anti-obesity medications, are vehemently opposed to the very notion that anti-obesity medications will one-day have a place in clinical obesity management. There are those, who given the past failures with dietary approaches (not unlike the failure of low-salt diets to produce long-term blood pressure lowering in most people), are ready to abandon dietary approaches all together (at least in the context of weight loss). Indeed, there are those who continue to argue that obesity is not really a disease but simply a risk factor attributable largely to lifestyle “choices”.

It took about 100 years for us to get to hypertension management as it exists today. In obesity, I think the wheels are moving a lot faster, although to many living with this disease, movement may appear glacial. Remember, less than 30 years have passed since the discovery of leptin. Only now are we entering the “modern” era of anti-obesity medications.

Yes, the debates about definitions and targets and treatment plans will continue but I am confident that sooner or later, we will get to the point where helping patients manage their obesity will be as routine, free of bias or judgement, and accepted as helping patients manage their hypertension.

Edmonton, AB


Is There A Role For Dietitians In Obesity Management?

Over the past 30 years, I have actively been involved in nutrition research – conducting numerous carefully controlled dietary studies ranging from the impact of electrolytes on blood pressure and renal function, to the impact of micro and macronutrients on insulin resistance and metabolism, to the role of genetic factors in response to nutrient intake. In all of this, dietitians have always been key players in my research team helping with the design and execution of these studies.

In my clinical work, I have regularly depended on the tremendous expertise of dietitians in the care of my patients with hypertension, chronic kidney disease, dyslipidemia, and type 2 diabetes – in virtually all of these conditions, dietitians have helped my patients on a wide range of treatments ranging from medications to chronic hemodialysis improve their diets, thereby significantly improving control of their underlying diseases or averting complications.

I have practiced medicine long enough to remember the days of prescribing low-salt diets before the modern era of anti-hypertensive medications, dietary lipid management before the introduction of statins, and worrying about glycosuria well-before most people considered type 2 diabetes to be an actual “disease” and not just a “risk factor” of questionable significance that happens to old people.

Thus, it is with a bit of wonder that I sense an increasing reluctance of some dietitians (at least in Canada) to fully embrace the important role that they could play in obesity management. At times, in recent conversations, I was surprised (and concerned) that more than a few (younger?) dietitians are not only uncomfortable with addressing obesity in their clients, they are in fact ambivilant (if not frankly hostile) to the very idea that obesity is a disease or that dietary interventions to support weight loss have a role to play in obesity management.

This, of course does not apply to the many excellent and skilled dietitians working in the many bariatric centres and obesity clinics, without who many of the successful outcomes in medical and surgical treatment of this chronic disease would hardly be possible.

Rather, ambivalence towards nutritional obesity management appears to emanate from folks who clearly do not (yet) have a sound understanding of the complex psycho-neurobiology of obesity or the mode of action and effectiveness of evidence-based obesity treatments that include medications and surgery.

Indeed, I cannot but wonder about these dietitians’ qualifications to actually contribute to the care of patients struggling with obesity. Imagine having your patient with diabetes being counselled by a dietitian who has never heard of insulin or glucagon, has only a vague idea of how SGLT2 agonists, DPP IV inhibitors, or GLP-1 analogues work, and firmly believes that typ2 diabetes can be fully controlled or even “cured” if patients only followed “healthy eating” tips. Imagine having your cholesterol managed by dietitians who don’t “believe” in cholesterol or statins, or your hypertension managed by dietitians who believe that some variation in blood pressure levels is acceptable and that simply reducing your salt intake and perhaps following the DASH diet is all you need to get off those terrible anti-hypertension meds.

This is unfortunate. Not only is there room for dietary interventions in obesity management, but, as in other chronic diseases, dietitians can (and should) be a key partner in the therapeutic management of people living with this chronic disease.

However, to be effective, dietitians need to first of all be comfortable with the very notion that obesity is a chronic disease. In the same way that any dietitian who does not “believe” in hypertention or type 2 diabetes should probably best stay away from counseling clients with these conditions, I would be wary of any dietary advice regarding managing my obesity from a dietition who does not “believe” in this disease.

Next, I would also expect any dietitian attempting to counsel patients for their obesity to have a robust understanding of the complex psycho-neuro biology of obesity, be aware of their own biases and misconceptions about people living with obesity, and be fully informed and aware of current evidence-based obesity treatments, including medications and surgery.

I would expect no less of a dietitian working with my patients living with hypertension or chronic kidney failure. Simply trying to get people living with obesity to follow a healthy balanced diet is not enough – different people living with obesity require different dietary approaches – approaches that change from patient to patient dependent on patient preferences, responses, circumstances, expectations, severity of disease, as well as concomitant use of medications and surgery.

I know that dietitians can do this when managing patients with a host of other chronic diseases – why some of them struggle to similarly serve clients with obesity, is frankly beyond me.

As we will soon see in the new Clinical Practice Guideline for Obesity Treatment in Adults to be released in 2020, there is strong and robust evidence to support nutritional interventions and dietary management of people living with obesity (in adjunct to, not instead of, medical and surgical management). But is it up to the dietetic profession to fully embrace this role and prepare its members for it by ensuring that their members fully understand and appreciate the emerging science of this complex chronic disease.

Edmonton, AB


Are You Living With Obesity? Time To Speak Up

Yesterday, at Obesity Week, I co-chaired a symposium on how stigma and weight-bias directly affects the health and health care of people living with obesity.

As several of the speakers pointed out, the prevailing false narrative that obesity is simply a matter of lifestyle “choices” that people make and that there are easy solutions (just eat-less move-more) is so dominant, that it has even been internalized by people living with obesity – they also believe that they have “done this to themselves” and “know what to do” (just eat less and move more), which is why they generally don’t reach out to health professionals and “demand” the standard of care and support that they would expect if they were living with a less stigmatized condition.

Indeed, in any other health area, people (and their family members) would hardly accept the almost complete lack of support or access to care (as for e.g. the grotesquely long wait-times for bariatric surgery) as people living with obesity are apparently willing to put up with.

Unfortunately, not speaking up and demanding the same level of health care as people living with other chronic diseases, is by far the #1 barrier to getting policy makers to move on this issue – as long as people living with obesity continue to blame themselves, feel “undeserving” of care, and are too ashamed to stand up for themselves, not much is going to change.

At Obesity Week, I also attended a full-day workshop of the international OPEN coalition, where I listened to experts on advocacy explain that the only way to ever effectively change policy is to speak up and speak out – not something most people living with obesity are comfortable with.

Unfortunately, there is no alternative – as long as people living with obesity are “OK” with being treated as “second-class” citizens and are “OK” with not having better access to proven and evidence-based obesity treatments, nothing will change.

If you are someone living with obesity who feels strongly that you should have the same right to supportive health care and treatments as people living with other chronic diseases, seek out and engage with organisations, who are there to help (e.g. Obesity Canada). Fortunately, you are not alone – there are millions of people living with obesity – if only a fraction of them stood up for themselves and demanded action – no politician seeking re-election could afford to ignore this issue.

If you are a healthcare provider, encourage your patents living with obesity to speak up and join and support organisations (e.g. Obesity Canada), who can help amplify their concerns and ultimately ensure that the health system allows you to provide the care that your patients need.

Las Vegas, NV


ABOM Master of Obesity Medicine

Yesterday, at the 2019 Obesity Week in Las Vegas, I had the honour of receiving the 2019 American Board of Obesity Medicine “Master of Obesity Medicine” award.

This is indeed a remarkable privilege, given that many of the previous distinguished award winners were folks that I have always looked up to, who have always offered their friendship and advice, and without whose mentorship, I would certainly not have developed the ideas or had the influence in obesity medicine that regular readers of these pages will be familiar with.

It was particularly humbling to see so many of my Canadian colleagues in the audience, who have always supported my endeavours and, in true Canadian fashion, have welcomed me to the Canadian research and practice community since I moved to Canada in 2002.

Finally, I owe this award to the many patients who have taught me much of what I know about obesity over the years.

If nothing else, this award will serve as a constant reminder that we continue to do what we can as researchers, clinicians, and advocates to make a difference in the lives of the millions of children and adults living with this complex chronic disease.

Las Vegas, USA


Report: ACTION on Obesity – it’s about time!

Today is officially World Obesity. As pointed out in the 252-page OECD report on “The Heavy Burden of Obesity: The Economics of Prevention”, Canada, like most OECD countries is not doing a great job at it (nor are others!). This leaves us with the fact that there are currently well over 6 million Canadian adults and children living with what the World Obesity Federation (and the Canadian Medical Association) calls a complex chronic disease.

So what is obesity and what does obesity care look like from the perspective of Canadians living with obesity (PwO), health care providers (HCPs), and employers? This is the topic of the Canadian ACTION Study, released today by Obesity Canada.

Conducted as a nationally representative survey, the ACTION study reveals that although people living with obesity, health care providers, and employers all agree that obesity is a significant health problem (on par with heart disease, diabetes, or even cancer), their views vastly differ when it comes to what to do about it.

Responses to the survey also suggest that people with obesity, health care providers and employers don’t fully understand the complexity of obesity, and believe that, contrary to current research findings, diet and exercise are sufficient approaches to managing it.

Based on the findings of the report, Obesity Canada makes the following recommendations:

For People Living with Obesity:

  • Learn evidence about obesity causes and treatments and understand that obesity management is a lifelong process that requires medical intervention.
  • Find health professionals who have been trained in obesity management.
  • Self-advocate for support and access to treatments and supports with Obesity Canada’s online resources.

For Health Care Providers:

  • Understand recent research supporting obesity’s complex etiology and heterogeneity.
  • Learn more about current evidence-based approaches to treating obesity (see Obesity Canada website).
  • Treat obesity as a chronic disease using available treatments (new Clinical Practice Guidelines available in 2020).
  • Include obesity in the training program curricula for health professionals.

For Employers:

  • Treat obesity as a chronic disease and move obesity out of the lifestyle category in bene ts plans.
  • Offer meaningful obesity services/coverage that move beyond healthy eating and exercise programs.

The Full ACTION Report ist available here.

An Infographic summarizing the key findings of the ACTION study is available here.

Edmonton, AB


The Clinical Importance Of The Limbic Dump

This week I am speaking at the LATAM Obesity Summit in Santaigo, Chile, where I again had occasion to hearing my Canadian colleague Michael Vallis (Halifax), speak about behavioural change.

In his talk, he discussed an important strategy in counselling patients, whch he referred to as the “limbic dump”. As readers will know, the limbic system is responsible for holding our emotions – anxiety, fear, apprehension, disappointment, frustration, but also, joy, optimism, anticipation, motivation.

In a classical doctor-patient encounter, the doctor generally focusses on analysing the problem (making the diagnosis) and giving advice (providing treatment) – both are functions that largely rely on the cognitive or “logical” part of our brains. The general idea is that, the doctor will provide rational information and advice to the patient, and the rational part of the patient’s brain will take in this advice and “follow instructions”.

Unfortunately, in most situations, this “rational” approach is overriden by the limbic or “emotional” part of the patient’s brain, which is far too busy dealing with feelings (shame, fear, anxiety, disappointment, frustration, etc.) to take in the “rational” information that is being provided.

This is where the “limbic dump” comes in. As Vallis points out, before getting into the “rational” part of any encounter, it is far more useful to begin by allowing the patient to first “dump” their concerns (or successes) on the table. Once these are out in the open, have been duly acknowledged, and discussed, the conversation can move on to the more “logical” transactional part of the encounter. Now, after the “limbic dump” you actually have a patient who is able to listen to what you have to say.

Of course, all experienced clinicians probably already know this. I, for one, generally start any patient encounter with an open ended question as to how the patient is feeling about how things are going. This gives them the opportunity to “dump” their feelings on the table – positive or negative. Only after acknowledging these (sometimes prompting them for details), do we move on to the more objective part of the encounter (I’m a big believer in motivational interviewing, so generally, I let my patients do most of the talking).

Now, thanks to Vallis, I have an explanation and term for what I have been doing all along – long-live the “limbic dump”.

Santiago, Chile


2nd International Symposium on Obesity Mechanisms, Leipzig 2019

For the past 10 years, I have had the rather exclusive privilege of being on the External Advisory Board (which I have chaired for the past five years) of the Integrated Research and Treatment Center (IFB) AdiposityDiseases, a multi-million Euro a joint research and clinical center of the University and the University Hospital Leipzig – sponsored by the German Federal Ministry of Education and Research. This funding period has now come to term (although obesity research will remain alive and kicking in Leipzig) and the 2nd International Symposium on Obesity Mechanisms, marks an important celebration of this milestone.

The three-day symposium, at which I will be presenting the Key Note Lecture, is held in collaboration with the DFG-funded SFB1052 and focuses on central obesity mechanisms, brain periphery crosstalk, adipose tissue heterogeneity, adipokines, and the clinical consequences of obesity. 

The findings and publications emanating from this research consortium over the past decade are far too numerous to mention in this post (publications appeared in the New England Journal of Medicine, The Lancet, Cell, Nature, Nature Medicine, and other top international journals).

As Matthias Blüher remarked in his opening address, many of these findings are now finding their way into translational research, including the testing of novel anti-obesity compounds and behavioural interventions based on findings from neuroimaging studies.

I, for one, have very much enjoyed being associated with these important efforts here in Leipzig and look forward to continuing involvement in the exciting work that continues to advance our understanding of this complex chronic disease.

Leipzig, Germany


Polyagonists for the Treatment of Obesity and Diabetes

This morning, I spoke at the German Diabetes Congress in Berlin on the issue of whether or not metabolic surgery offers a cure (or just remission) in patients with type 2 diabetes.

I also had the pleasure of attending the Hans Langerhans Award Lecture, the highest distinction awarded by the German Diabetes Society, given by my colleague Matthias Tschöp, who is also the Director of the Helmholtz Centre for Diabetes Research in Munich.

Tschöp focussed his acceptance speech on his ground-breaking work on polyagonists, i.e. molecules that can co-stimulate two or more peptide receptors (e.g. for GLP-1, GIP, and glucagon).

Tschöp began his presentation by declaring that we could almost completely reverse the global epidemic of type 2 diabetes, if only we had more effective treatments for obesity.

As we now know, appetite and energy regulation is tightly controlled by a host of neuroendocrine signals, which act on the central nervous system as part of a complex homeostatic system that acts to sustain and defend body weight.

Based on these findings, Tschöp’s work has pursued the notion that effective obesity treatments require targeting of the homeostatic centres in the brain. As we have learnt from the extensive research on bariatric surgery, there are a number of signal molecules released by the gut (incretins) that directly affect central mechanism of appetite and satiety.

However, given the complexity and redundancy of the system, just targeting one of these molecules may not be effective enough to counteract the powerful mechanisms that defend against long-term weight loss. This insight, led Tschöp to pursue the idea that developing single synthetic molecules, that could simultaneously stimulate  several distinct but synergistic pathways, may prove to be more effective than targeting a single molecular target.

This idea, ultimately led to the development of molecules that simultaneously act as dual co-agonists (e.g. for GLP-1 and glucagon or for GLP-1 and GIP ) or even tri-co-agonists (e.g. for GLP-1, GIP, and glucagon). These co-agonists appear to have potent metabolic and anti-obesity effects both in animal models and in early human studies. Indeed, this approach is now being actively pursued by a number of pharmaceutical companies hoping for more effective anti-obesity medications.

While these studies are currently underway, they certainly hold great promise for the future of medical treatments for obesity and diabetes.

Congratulations to Matthias Tschöp and his team for this most well-deserved award.

Berlin, Germany

p.s. As an aside, I will have the pleasure of playing guitar with the “Sugar Daddies”, featuring Matthias Tschöp on drums (along with other prominent German diabetes researchers) at the Diabetes Gala Evening this evening.