The OPQRST Of Body Weight

The assessment of weight history is no doubt a key feature of obesity assessment. Not only can weight history and trajectories provide important insights into obesity related risk but, perhaps more importantly, provide key information on precipitating factors and drivers of excessive weight gain. Now, in a short article published in MedEdPublish, Robert Kushner discusses how the well-known OPQRST mnemonic for assessing a “chief complaint”  can be applied to assess body weight. In short, OPQRST is a mnemonic for Onset, Precipitating, Quality of Life, Remedy, Setting, and Temporal pattern. Applied to obesity, Kushner provides the following sample questions for each item: Onset: “When did you first begin to gain weight?” “What did you weight in high school, college, early 20s, 30s, 40s?” “What was your heaviest weight?” Precipitating: “What life events led to your weight gain, e.g., college, long commute, marriage, divorce, financial loss?” “How much weight did you gain with pregnancy?” “How much weight did you gain when you stopped smoking?” “How much weight did you gain when you started insulin?” Quality of life: “At what weight did you feel your best?” “What is hard to do at your current weight?” Remedy: “What have you done or tried in the past to control your weight?” “What is the most successful approach you tried to lose weight?” “What do you attribute the weight loss to?” “What caused you to gain your weight back?” Setting: “What was going on in your life when you last felt in control of your weight?” “What was going on when you gained your weight?” “What role has stress played in your weight gain?” “How important is social support or having a buddy to help you?” Temporal pattern: “What is the pattern of your weight gain?” “Did you gradually gain your weight over time, or is it more cyclic (yo-yo)?” “Are there large swings in your weight, and if so, what is the weight change?” As Kushner notes, “These features provide a contextual understanding of how and when patients gained weight, what efforts were employed to take control, and the impact of body weight on their health. Furthermore, by using a narrative or autobiographical approach to obtaining the weight history, patients are able to express, in their own words, a life course perspective of the underlying burden, frustration, struggle, stigma or shame associated with trying to manage body weight. Listening should be unconditional and nonjudgmental. By letting patients tell their story, the… Read More »

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How The Body Weighs Itself – Evidence For A Bone “Gravitostat”

In my talks, I have often joked about how to best keep weight off – just carry around a backpack that contains the lost pounds to fool the body into thinking the weight is still there. It turns out that what was intended as a joke, may in fact not be all too far from how the body actually regulates body weight. As readers of these posts are well aware, body weight is tightly controlled by a complex neuroendocrine feedback system that effectively defends the body against weight loss (and somewhat, albeit less efficiently, protects against excessive weight gain). Countless animal experiments (and human observations) show that following weight loss, more often than not, body weight is regained, generally precisely to the level of initial weight. With the discovery of leptin in the early 90s, an important afferent part of this feedback system became clear. Loss of fat mass leads to a substantial decrease in leptin levels, which in turn results in increased appetite and decreased metabolic rate, both favouring weight regain and thus, restoration of body weight to initial levels. Now, an international team of researchers led by John-Olov Jansson from the University of Gothenburg, Sweden, in a paper published in the Proceeding of the National Academy of Science (PNAS), provides compelling evidence for the existence of another afferent signal involved in body weight regulation – one derived from weight-bearing bones. Prompted by observations that prolonged sedentariness can promote weight gain, independent of physical activity, the researchers hypothesised that, “…there is a homeostat in the lower extremities regulating body weight with an impact on fat mass. Such a homeostat would (together with leptin) ensure sufficient whole body energy depots but still protect land-living animals from becoming too heavy. A prerequisite for such homeostatic regulation of body weight is that the integration center, which may be in the brain, receives afferent information from a body weight sensor. Thereafter, the integration center may adjust the body weight by acting on an effector.” In a first series of experiments, the researchers observed that implanting a weight corresponding to about 15% of body weight into rodents (rats and mice), resulted in a rapid “spontaneous” adjustment in body weight so that the combined weight of the animal plus the weight implant corresponded more-or-less to that of control animals. Within two weeks of implanting the weights, ∼80% of the increased loading was counteracted by reduced… Read More »

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The Key To Obesity Management Lies In The Science Of Energy Homeostasis

If there is one thing we know for sure about obesity management, it is the sad fact, that no diet, exercise, medication, not even bariatric surgery, will permanently reset the body’s tendency to defend and regain its body weight to its set point – this generally being the highest weight that has been achieved and maintained for a notable length of time. Thus, any effective long-term treatment has to offset the complex neurobiology that will eventually doom every weight-loss attempt to “failure” (no, anecdotes don’t count!). Just how complex and overpowering this biological system that regulates body weight is, is described in a comprehensive review by the undisputed leaders in this field (Michael Schwartz, Randy Seeley, Eric Ravussin, Rudolph Leibel and colleagues) published in Endocrine Reviews. Indeed the paper is nothing less than a “Scientific Statement” from the venerable Endocrine Society, or, in other words, these folks know what they’re talking about when it comes to the science of energy balance. As the authors remind us, “In its third year of existence, the Endocrine Society elected Sir Harvey Cushing as President. In his presidential address, he advocated strongly in favor of adopting the scientific method and abandoning empiricism to better inform the diagnosis and treatment of endocrine disease. In doing so, Cushing helped to usher in the modern era of endocrinology and with it, the end of organo-therapy. (In an interesting historical footnote, Cushing’s Energy Homeostasis and the Physiological Control of Body-Fat Stores presidential address was given in , the same year that insulin was discovered.)” Over 30 pages, backed by almost 350 scientific citations, the authors outline in excruciating detail just how complex the biological system that regulates, defends, and restores body weight actually is. Moreover, this system is not static but rather, is strongly influenced and modulated by environmental and societal factors. Indeed, after reading this article, it seems that the very notion, that average Jane or Joe could somehow learn to permanently overcome this intricately fine-tuned system (or the societal drivers) with will power alone is almost laughable (hats off to the very few brave and determined individuals, who can actually do this – you have climbed to the top of Mount Everest and decided to camp out there for the foreseeable future – I wish you all the best!). Thus, the authors are confident that, “The identification of neuromolecular mechanisms that integrate short-term and long-term control… Read More »

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Alternate Day Fasting Is No Better Than Any Other Fad Diet

It seems that every year someone else comes up with a diet that can supposedly conquer obesity and all others health problems of civilization. In almost every case, the diet is based on some “new” insight into how our bodies function, or how our ancestors (read – hunters gatherers (never mind that they only lived to be 35) ate, or how modern foods are killing us (never mind that the average person has never lived longer than ever before), or how (insert remote population here) lives today with no chronic disease. Throw in some scientific terms like “ketogenic”, “guten”, “anti-oxidant”, “fructose”, or “insulin”, add some level of restriction and unusual foods, and (most importantly) get celebrity endorsement and “testemonials” and you have a best-seller (and a successful speaking career) ready to go. The problem is that, no matter what the “scientific” (sounding) theories suggest, there is little evidence that the enthusiastic promises of any of these hold up under the cold light of scientific study. Therefore, I am not the least surprised that the same holds true for the much hyped “alternative-day fasting diet”, which supposedly is best for us, because it mimics how our pre-historic ancestors apparently made it to the ripe age of 35 without obesity and heart attacks. Thus, a year-long randomised controlled study by John Trepanowski and colleagues, published in JAMA Internal Medicine, shows that alternate day fasting is evidently no better in producing superior adherence, weight loss, weight maintenance, or cardioprotection compared to good old daily calorie restriction (which also produces modest long-term results at best). In fact, the alternate day fasting group had significantly more dropouts than both the daily calorie restriction and control group (38% vs. 29% and 26% respectively). Mean weight loss was virtually identical between both intervention groups (~6 Kg). Purists of course will instantly critisize that the study did not actually test alternative-day fasting, as more people dropped out and most of the participants who stayed in that group actually ate more than prescribed on fast days, and less than prescribed on feast days – but that is exactly the point of this kind of study – to test whether the proposed diet works in “real life”, because no one in “real life” can ever be expected to be perfectly compliant with any diet. In fact, again, as this study shows, the more “restrictive” the diet (and, yes, starving yourself… Read More »

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Zona Incerta Stimulation Provokes Instant Binge Eating in Mice

The neuronal control of appetite and food intake is among the most complex and fascinating systems. Now, in a paper published in Science, Xiaobing Zhang and Anthony van den Pol from Yale University, New Haven, report the identification of a novel role of the zona incerta in inducing profound binge eating behaviour in mice. The zona incerta, is a little know part of the central nervous system within the subthalamus with extensive projections all the way from the cerebral cortex into the spinal cord. It is thought to play an important role in limbic-motor integration as well as synchronizing brain rhythms. The researchers showed that optogenetic stimulation of zona incerta GABA neurons or their axonal projections to paraventricular thalamus excitatory neurons rsults in an immediate (in 2 to 3 seconds) binge-like eating behaviour – the animals ate up to 35% of their total energy requirements in just 10 mins. Furthermore, while intermittent stimulation of these neurons led to body weight gain, ablation reduced weight. The authors suggest that the identification of this novel orexigenic system may lead to better treatments not just for binge-eating disorder. @DrSharma Edmonton, AB  

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