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Residential Schools And Indigenous Obesity – More Than Just Hunger?

A recent CMAJ article, by Ian Mosby and Tracey Galloway from the University of Toronto argues that one of the key reasons why we see obesity and diabetes so rampant in Canada’s indigenous populations, is the fact that widespread and persistent exposure to hunger during the notorious residential school system may have metabolically “programmed” who generations toward a greater propensity for obesity and type 2 diabetes. There is indeed a very plausible biological hypothesis for this, “Hunger itself has profound consequences for childhood development. Children experiencing hunger have an activated hypothalamic–pituitary–adrenal stress response. This causes increased cortisol secretion which, over the long term, blunts insulin response, inhibits the function of insulin-like growth factor and produces long-term changes in lipid metabolism. Through this process, the child’s physiology is essentially “programmed” by hunger to continue the cycle of worsening effects, with their bodies displaying a rapid tendency for fat-mass accumulation when nutritional resources become available.” While the impact of hunger may well have been one of the key drivers or metabolic changes, the authors failed to acknowledge another (even more?) important consequence of residential schools – the impact on mental health. Oddly enough, in a blog post I wrote back in 2008, I discussed the notion that the significant (and widespread) physical, emotional, and sexual abuse experienced by the generations of indigenous kids exposed to the residential school system would readily explain much of the rampant psychological problems (addictions, depression, PTSD, etc.) present in the indigenous populations across Canada today. The following is an excerpt from this previous post: This disastrous and cruel [residential school] policy resulted in much pain and despair in the First Nations’, Inuit and Metis people that lasts to this day (known as the “generational effect”). Sexual, physical and mental abuse was widespread; students were broken in heart and spirit; culture and identities were destroyed. Much (if not all) of what ails the Aboriginal peoples of Canada can be traced back to this policy – including possibly issues that affect Aboriginal health to this day. It is no secret that obesity and its consequences (e.g. diabetes) are rampant amongst the Aboriginal peoples of Canada. While poverty, breakdown of traditional lifestyle and culture and even genetic factors (thrifty genotype) have all been implicated in this, I wonder how much the misery caused by the residential school program had to contribute. Early traumatic life experiences including sexual, mental and physical… Read More »

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Balancing Benefits And Harms From Redefining Obesity

The final and eight 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,  deals with issue of determining the benefit/harm ratio of the proposed new definition. With terms to redefining obesity as the presence of abnormal or excess body fat that impairs health, I have discussed the potential benefits and harms in previous posts. The question is, whether or not the overall balance comes down on the benefit or harm side of the equation. Here, the authors of the checklist have the following to offer, “Modifying a disease definition should be guided by a balanced assessment of the anticipated benefits and harms, using the best evidence available. The definition should reflect the values and preferences of patients and the wider community and include the impact on resource usage….In general, we recommend that panels consider both an individual and societal approach to assessing the overall benefits and harms of changing disease definitions. We recommend introducing a new disease definition where there is an expected positive balance of harms and benefit for individuals, and in aggregate at the societal level.” In addition, the authors note, “Different definitions may be required for research purposes, for example more stringent standardization, than for clinical purposes where more stringent definitions may deny access to care for patients who would benefit.” Thus, as we have seen, changing disease definitions is not just a matter of opinion but rather, the pros and cons must be considered both at an individual and societal (resource) level. That said, disease definitions are in constant flux as new knowledge and treatments emerge – obesity, should be no exception. Indeed, guidelines would be amiss in not reconsidering the validity of current definitions and exploring potential changes as part of the guidelines process. The published checklist can certainly serve as a guide for this process. @DrSharma Edmonton, AB

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Are There Any Harms Of Redefining Obesity?

The seventh 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,  deals with issue of potential harms to patients. Given the obvious benefits of redefining obesity as the presence of abnormal or excess body fat that impairs health outlined in the previous post, it is nevertheless prudent to explore the possibility of unintentional harms. Obviously, expanding the term obesity to include millions of people, who currently fall under the BMI threshold but may well have health impairments attributable to their body fat, may not sit well with these folks. In fact, they may find themselves shocked to learn that they would now be considered to have obesity (more a reflection of the stigma attached to this term, than its non-judgemental medical meaning). Thus, the authors of checklist remind us that, “The potential harms from diagnosis include the physical harms of diagnosis and treatment; psychological effects, such as anxiety; social effects, such as stigma and discrimination; and financial consequences, such as effects on employment….Potential harms also include the misapplication and misinterpretation of the disease definition when taken from a confined research application to more widespread clinical use.” A, perhaps more concerning issue, is the impact that redefining obesity may have on limited resources for obesity management in the healthcare system. “Changes in resource usage can result in harm by reducing access to care for some patients and by diversion and distraction of clinical care. This can happen at both the societal level, with resources taken from areas more important to health, and at the individual level, by distracting individuals from activities more important to their well-being. Modifications of disease definitions can have considerable impacts on costs, including the costs of testing, and the resources needed for treatment and follow-up for those diagnosed using the new criteria. There may also be resources needed for training and implementation regarding the change, and to minimise misdiagnosis. Costs are particularly important in low- and middle-income countries where inappropriate disease definitions can result in considerable diversion of limited health care resources.” These concerns are far from trivial. Not only are current resources for managing obesity in our healthcare systems limited (to non-existant), but one of the main reasons that employers and payers balk at providing access to obesity treatments, is the sheer number of individuals that already qualify for such treatments. Significantly expanding the pool of eligible patients, is therefore. unlikely to be met with much enthusiasm from these stakeholders. Not only would one need to demonstrate… Read More »

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How Will Patients Benefit From Redefining Obesity?

The sixth 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,  deals with issue of incremental benefits to patients. With the current BMI-based definition, this measure is generally used to decide whether or not a given patient receives obesity treatments. But, as readers are aware, not everyone with a BMI over a certain threshold would have the same degree of health issues (if any) and therefore not everyone currently classified as having obesity would necessarily benefit from treatment. On the other hand, there are a substantial number of individuals who currently fall below the BMI threshold, but have significant health problems attributable to the presence of abnormal or excess body fat. These individuals, would currently not have access to obesity treatments. Thus, as the authors of the checklist point out, “Wherever changes in disease definitions will alter which patients receive treatment, it isessential to assess treatment benefits and harms, focusing on the balance of benefits and harms for those diagnosed by the new definition and not diagnosed by the previous definition. Changes to disease definitions can provide benefits to patients, mostly by providing access to treatments  with beneficial effects.” However, the authors also warn that, “…evidence from previous treatment trials in patients with later or more severe disease cannot be extrapolated to patients with milder or less severe disease…” This means that evidence for treatment benefits will require clinical trials to include participants covered by the new definition. Guideline committees should also consider the possibility that broadening the diagnosis may provide validation of symptoms and access to social and other benefits in individuals not previously qualifying for such benefits. @DrSharma Berlin, D

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Precision and Accuracy of Defining Obesity

The fifth 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,  deals with issue of precision, accuracy, and reproducibility. Obviously, any definition of obesity that requires clinical assessment and clinical judgement will not have the precision, accuracy, or reproducibility of simply measuring height and weight. Thus, if we define obesity as the presence of abnormal or excess body fat that impairs health, we will necessarily have to deal with the issue of assessing health, which is not something that you can simply measure by stepping on a scale. Rather, because abnormal or excess fat can affect virtually every organ system as well as psycho-social well-being, we are going to be faced with a rather complex system of diagnosing who has obesity and who hasn’t. In fact, as the authors of the checklist point out, “…an appropriate gold standard will rarely be available and therefore, traditional measures of diagnostic test accuracy, such as sensitivity and specificity, will generally not be appropriate.” Both repeatability (agreement in identical conditions) as well as reproducibility (agreement across comparable conditions) may result from biological variability, analytical variability, and clinical judgement. The only way to test the reproducibility and precision will be to evaluate the use of the new definition in clinical practice and ultimately determining whether or not clinicians can reasonably agree on who has the condition and who doesn’t. While this may seem daunting to non-clinicians, let us remember that in clinical practice many diagnoses are dependent on clinical evaluations and clinical judgement, whereby experienced clinicians or specialists may perform better than the novice or the non-specialist (a good example is psychiatry, but there are countless other examples). Moreover, there will always be grey areas in “borderline” cases, where examiners may disagree on the exact result and only time will tell, who is right. Welcome to the messy world of clinical practice. Just because BMI is simpler, more precisely measured, and more reproducible, does not make it a better measure of diagnosing whether or not someone actually has a disease. After all it only makes sense that it will take a complex definition to diagnose a complex disease. @DrSharma Edmonton, AB

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