Almost exactly to this date 10 years ago, we published a paper in HYPERTENSION discussing the potential for weight gain associated with the use of beta (β) blockers (drugs that, at the time, were widely use for treating high blood pressure and presently continue to be routinely used for the management of coronary artery disease and heart failure). As we discussed in our paper, sympathetic activation is an important metabolic adaptation limiting weight gain and, therefore chronic β-blocker therapy could increase the propensity for weight gain by reducing energy expenditure. This question was now readdressed by Lee and colleagues from Sydney, Australia, in a paper just published in the International Journal of Obesity. In the current study, the reseachers first performed a mechanistic study comparing energy expenditure, diet-induced thermogenesis, and habitual activity levels between volunteers (n=11) with uncomplicated hypertension treated with a β-blocker and anthropometrically matched controls (n=19) and found that β-blocker treatment reduced diet-induced thermogenesis by around 50%, fat oxidation rate by 32% and weekly habitual activity levels by 30%. They then examined data from three cross-sectional studies consisting of around 200 patients with diabetes, 80 patients with hypertension and over 11,000 participants in a large multi-centre diabetes trial (ADVANCE). In all three populations, β-blocker treated patients had higher body weights: about 9 kg higher in the diabetes patients, around 17 kg higher in the hypertension patients, and around 5 kg higher in the ADVANCE trial. The authors conclude that total energy expenditure (both from reduction in post-prandial thermogenesis and reduced activity levels is reduced and therefore body weight may significantly increase under chronic β-blocker use. These findings must be interpreted with some caution, as ß-blockers consist of a very heterogeneous group of compounds with varying propensity for weight gain (e.g. carvedilol and nebivolol may have far less impact on weight than propranolol or atenolol). Furthermore, this side-effect of ß-blockade should not distract from the fact that this class of drugs has saved 100s of 1000s of lives in patients with coronary artery disease or heart failure and should definitely not simply be discontinued in patients who need them. On the other hand, clinicians should be aware of this side effect and advise patients to carefully monitor their weight to decrease the risk for weight gain – as always, prevention of weight gain is easier than treatment. Fortunately, we now have a variety of other drugs for the treatment of… Read More »
Currently, I am in Leipzig, Germany, home of the latest Integrated Research and Treatment centre funded by a substantial grant (~24 Million Euros) from the German federal ministry of research and education. As you may guess, this centre will focus on obesity, an area in which the University of Leipzig already has considerable expertise. As part of the International Advisory Board to this centre, it is my role to advise the board of this project regarding the best ways to ensure that this substantial grant is put to the best possible use. There is no doubt that the project is highly innovative, cutting straight through Germany’s traditional hierarchical and archaic academic structures, where the “Herr Professor”, once appointed for life, pretty much has the final say on anything that happens in a given department. The integrated Research and Treatment centres are specifically designed to cut through these bureaucratic and often ineffective feifdoms, a concept which may well revolutionize medical practice and research at German universities. I definitely had the pleasure of hearing about a wide range of novel ideas and was very much impressed by the many cross-sectorial research projects ranging from cutting edge work on the biological function of adipose tissue to the psychiatric issues that patients face after bariatric surgery. To top things off, our most generous hosts invited us to a fabulous evening at the 500 year old Auerbach Keller, which apparently was a regular hang out for Goethe during his time in Leipzig and currently ranks #5 under the most visited restaurants in the world (after Munich’s Hofbräuhaus, Caesar´s Palace in Las Vegas, Café Sacher in Wien and the Hard Rock Café in LA). Of course, as to be expected at this historical venue, the evening was accompanied by a recital from Goethe’s Faust in the typical Saxonian dialect. I congratulate Michael Stumvoll and his colleagues on their success in acquiring a substantial amount of funding to establish, what I can only assume will soon be Germany’s leading Centre of Excellence in obesity research and management. Apart from the honour of serving on their International Advisory Board, I certainly very much look forward to future interactions, especially given the recent collaboration agreement between the German Freestate of Saxony and the University of Alberta. AMS Leipzig, Germany
Anyone still hoping that school-based exercise programs will prove to be the “silver bullet” against childhood obesity should probably read the latest meta-analysis on this topic, just out in this week’s issue of CMAJ. In this carefully conducted analysis of the literature, Kevin Harris and colleagues from BC Children’s Hospital, Vancouver, BC, Canada, find no evidence to suggest that school-based physical activity interventions improve BMI, although they certainly have other beneficial health effects. This finding is not unexpected – not only is exercise alone simply not the most efficient way to control weight, it is also not likely that an intervention that only addresses a small proportion of childrens’ total daytime activity will have any measurable impact on body weight. This does not mean that increasing activity in school is bad – as pointed out before in these pages – there are numerous other benefits of being physically active. It so happens that just yesterday, I had the pleasure of listening to Dr. Mark Tremblay, Professor of Pediatrics at the Children’s Hospital of Eastern Ontario and Chief Scientific Officer of Active Healthy Kids Canada, at the 4th University of Alberta Annual Nutrition Symposium, hosted by the Students of Nutrition 440. As Tremblay pointed out: to affect body weight, the target should be to reduce sedentariness – which is not the same as increasing the amount of exercise. There is no reason to assume that a few extra minutes of physical activity at school can cancel out the many hours of screen time and the considerable time spent indoors, not to mention the deleterious effects of caloric-dense unhealthy diets. AMS Edmonton, Alberta p.s. Thanks to all the students who hosted “Obesity: Why the Weight?” – I had a great time – thanks for inviting me.!
Yesterday, I attended a special symposium hosted by the Canadian Association of Bariatric Physicians and Surgeons (CABPS) in Halifax. While Mehran Anvari (McMaster University) spoke on the recent announcement of $75 Million in funding for Bariatric Centres of Excellence in Ontario, Nikolas Christou (McGill University) emphasized the urgency for similar decisions in other provinces, including Quebec. Bariatric surgeons trying to develop programs in Regina (Saskatchewan), Moncton (New Brunswick), Richmond (British Columbia) and elsewhere, commented on their efforts and the tremendous and overwhelming demand on their services. In my presentation, I called for a nation-wide initiative to improve access to bariatric care, not just surgical treatments, but also for medical, mental health and rehabilitation services. I also emphasized that providing treatments to the over 5 Million Canadians struggling with obesity is unrealistic without full engagement of family doctors and family health teams or primary care networks across the country. Not treating obesity, in the end, means treating the complications – obesity treatment IS prevention! AMS Halifax, Nova Scotia
Anyone involved in chronic disease management is well aware how difficult it is for patients to stick with even the simplest of medical regimens – just taking a tablet once a day. This is even more difficult for patients with psychiatric issues (present in over 40% of treatment-seeking patients with obesity). Less than half of patients prescribed medication for depression will still be on their drug 3 months after initiation; with bipolar disorder, this rate drops to only 35%. Pharmacological obesity trials regularly show high-rates of discontinuation (around 20-40% at 12 months), not very different from that seen in real life for blood pressure or lipid-lowering medications. If simply taking a tablet is so hard to stick to, how much more difficult is it to actually make lifestyle changes and stick with them? No question, patients struggling with excess weight need constant coaching, reminders, self-monitoring, support systems – left to their own devices the vast majority of patients will fall back into their old patterns resulting in weight regain. As I often say – there are only two types of obese patients – those that are untreated and those that are treated. The only difference between the two groups is the fact that patients in the treatment group are managing their weights – when treatment stops, group 2 reverts to group 1 – i.e. the weight comes back or continues to increase – there are no exceptions! As with other chronic diseases, our challenge in obesity is not how to get patients to start treatment – the challenge is how to get patients to stick with the treatment forever. AMS Edmonton, Alberta Schematic: World Health Organization, 2003