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Search Results for "bariatric surgery"

What Do People (Want to) Eat After Bariatric Surgery?

The reason that medications and surgery work so much better for managing obesity than behavioural interventions alone, is because they change the underlying biology that drives weight gain and defends against weight loss. Thus, rather than relying on willpower, these treatments change ingestive behaviour by modifying the complex neuroendocrine pathways that regulate food intake.  So what exactly do people who undergo bariatric surgery experience in terms of wanting and liking foods and how does their dietary intake change following surgery? This is the topic of a systematic review and meta-analyses of food preference modifications after bariatric surgery by Erika Guyot and colleagues from the University Laval, Quebec, Canada, published in Obesity Reviews.  Apart from the homeostatic control of energy intake, the authors remind us that, “Food intake is partly under the control of the reward system (tonsil, ventral tegmental area, hypothalamus, limbic system, and prefrontal cortex). This system assigns a hedonic value to food and generates motivation for food intake. Food reward has been shown to have two distinct components. The first component is “liking” and is related to the pleasure and the sensory properties of foods. The second component is “wanting”, which is related to the motivation and is defined as an implicit drive to eat.”   Both of these components of food intake have been reported to be altered in patients post-surgery and imaging studies have shown a decrease in the potential of palatable foods’ ability to activate the relevant areas of the brain in post-surgical patients.  The authors included 57 studies in their review (47 studies were prospective, 8 were cross-sectional, and 2 were longitudinal retrospective) that included 2,271 patients with RYGB and 903 patients with SG. As expected, there was significant heterogeneity amongst the studies, which used a total of 16 different methods to assess food intake and preferences, with the majority being based on food records (N = 24), Food Frequency Questionnaires (FFQ) (N = 12), and food recalls (N = 11). Likewise, time points for assessment ranged from days to months post-surgery all the way up to 10 years later.  Despite these methodological differences, a couple of important themes emerged. Overall, despite a marked reduction in caloric intake, there was a significant increase in protein intake (from baseline), with a reduced intake of calories from fat. Carbohydrate intake, as a proportion of overall caloric intake, was largely unaltered.  Perhaps more interestingly, several studies also described differences in food preferences. Thus,… Read More »


Can Gastrointestinal Effects Alter Mental Health After Bariatric Surgery?

Although the overall impact of bariatric surgery on mental health is overwhelmingly positive, there remains a subset of individuals in whom mental health issues like self-harm or addictions may appear after surgery.  Now a paper by Robyn Brown and colleagues, published in Nature Reviews Endocrinology, presents an intriguing hypothesis, that alterations in the gut-axis may play a role in these problems.  As readers are well aware, bariatric surgery (with some variations depending on the type of procedure) results in profound changes in gut function including alterations in incretin release, intestinal flora, bile acid disposition, and vagal signaling. As discussed in the paper, all of these factors may potentially affect mental health. However, the evidence is sparse and often contradictory. As the authors point out, despite a strong potential for some of these alterations induced by surgery to alter mental health, few mechanistic studies appear in the animal or clinical literature that could potentially lead to better mechanistic insights and hopefully effective preventive and treatment measures.   Be the role of the gut in adverse mental health outcomes after bariatric surgery as it may, it’s perhaps important to recall that there are plenty of other probable contributing factors to adverse mental health in bariatric patients.  These include high rates of pre-existing depression, unmet expectations regarding the life-changing effects of weight loss, post-surgical alterations in the absorption of antidepressant and anxiolytic medications, and changes in alcohol metabolism, which might increase disinhibition and impulsivity, leading to self-harm.  In addition weight regain and recurrence of weight-related comorbidities, body dissatisfaction (perhaps heightened by excess skin after weight loss), as well as the reduced capacity to eat or enjoy highly-palatable foods as an emotional coping strategy may play a role in individual patients. Thus, although fear of mental health issues post surgery should probably not deter anyone from undergoing surgery if they really need it, clinicians should be aware of the possibility of adverse mental health outcomes and counsel and monitor patients accordingly.  DrSharma,Berlin, D


How Many Years Can Bariatric Surgery Add To Your LIfe?

Yesterday, I discussed the impact of bariatric surgery on life expectancy in Ontario, Canada, which showed a clear positive impact on reducing overall mortality, particularly from cardiovascular disease and cancer.  But this study is by far not the only data we have on this issue. In fact, a recent meta-analysis by Nicholas Syn and colleagues, published in The Lancet, should dispel any remaining doubts as to the overall impact of having bariatric surgery. The authors looked at data from over 170,000 participants across 16 matched cohort studies and one prospective controlled trial (the one from Ontario not included!), representing over 1,2 Million patient years.  Overall bariatric surgery was associated with a reduction in hazard rate of death of 49·2% with median life expectancy being 6·1 years longer than with usual care. In fact, for patients with diabetes, life expectancy was 9.3 years longer (compared to 5.1 years longer in participants without diabetes). Based on these observations, the numbers needed to treat to prevent one additional death over a 10-year time frame was  slightly greater than 8 for those with diabetes vs. 30 for those without diabetes. This, by any measure, puts bariatric surgery squarely in place as one of the most effective treatments for any serious condition in all of medicine! In an interesting extrapolation of these results to the global pool of potential surgery candidates, the authors project that even just a 1% increase in rates of bariatric surgery, could translate into 5.1 to 6.6 millions potential life-years saved.  To anyone who would still prefer to pooh-pooh this vast body of evidence, because they only “believe” in randomised controlled trials, the authors point out that, “Randomised clinical trials with sufficient power to assess a rare outcome such as mortality are unlikely to ever be done because such studies require large sample numbers, long-term follow-up spanning decades, and are prohibitively expensive. “ So, this may well be the best evidence we may ever have on this issue – take it or leave it. Either way, finding a justification to deny or discourage patients with severe obesity from seriously considering surgery as a treatment for their chronic disease is becoming increasingly untenable.  @DrSharmaBerlin, D


Saving Lives With Bariatric Surgery ?

In all of my years of working with patients who have undergone bariatric surgery, the most common regret I got to hear was, “I regret waiting so long before deciding to have it”. While people who have had surgery often look back on the years of good life lost due to their obesity, the good news is that we now have an increasing body of evidence showing that having bariatric surgery does likely increase your life expectancy, thereby increasing your overall lifespan.  Case in point is the recent paper by Aristithes Doumouras and colleagues from McMaster University, Hamilton, Ontario, published in the Annals of Internal Medicine, showing that undergoing bariatric surgery is associated with a significant reduction in overall mortality. In this observational study, the researchers compared outcomes in over 13,000 patients who underwent bariatric surgery in Ontario, Canada (which has a public healthcare system), to over 13,000 non-surgical patients matched for index date, age, sex, BMI, diabetes status, and diabetes duration.  As is typical for most bariatric patients, more than 80% were female, with a mean age of around 45 years and a baseline BMI of 47. Gastric bypass was the most common procedure (87%) with the rest receiving sleeve gastrectomies. After a median follow-up of just 4.9 years, the overall mortality rate was 1.4% (n = 197) in the surgery group and 2.5% (n = 340) in the non-surgery group, with a lower adjusted hazard ratio (HR) of overall all-cause mortality (HR, 0.68 [95% CI, 0.57 to 0.81]).  The risk reduction was even greater in patients aged 55 or older with a lower HR of mortality in the surgery group (HR, 0.53 [CI, 0.41 to 0.69]).  Much of this reduced mortality risk was attributable to lower cardiovascular mortality (HR, 0.53 [CI, 0.34 to 0.84]) and lower cancer mortality (HR, 0.54 [CI, 0.36 to 0.80]). Although the nature of observational studies is such that one should be cautious in jumping to conclusions regarding causality, the data do strongly support the notion that bariatric surgery may indeed save lives.  This is not to say that bariatric surgery is entirely without risk – after all, it is still major surgery, where things can always go wrong. On the other hand, for people living with sever obesity, having bariatric surgery appears to be the less risky option, at least as far as mortality is concerned.  While these data are both impressive and reassuring,… Read More »


Bariatric Surgery For Adolescents – 5 Year Outcomes

Given that our efforts to stop the childhood obesity have so far yet to show any signs of success and that treatment efforts of kids already struggling with excess weight have been sketchy at best, there is unfortunately a growing number of adolescents living with severe obesity, for who we have very little choice but to consider bariatric surgery. As drastic as surgery may seem, it is important to recognise that for adolescents weighing in at 250 lbs or more, waiting and hoping for obesity to spontaneously resolve, while these kids miss out on opportunities ranging from education to social relationships (never mind the bullying and discrimination), is hardly an acceptable option. Thus, a study by Thomas Inge and colleagues published in the New England Journal of Medicine, showing that 5-year outcomes of adolescents undergoing bariatric surgery are as positive as in (most) adults, is heartening. The study looks at 5-year outcomes in 161 adolescent patients enrolled from 2006 through 2012) and a cohort of adults (396 patients enrolled from 2006 through 2009) undergoing Roux-en Y gastric bypass surgery. Overall, the extent of weight loss 5 years after surgery in the adolescents (-26%) was similar to that in adults (-29%). Adolescents were significantly more likely than adults to have remission of type 2 diabetes (86% vs. 53%) and of hypertension (68% vs. 41%). Three adolescents (1.9%) and seven adults (1.8%) died in the 5 years after surgery. In the adolescent cohort, one death was attributed to suspected sepsis in a patient with type 1 diabetes who had multiple complications after a hypoglycemic episode 3 years after surgery, and features of the other two deaths in adolescents, both of which occurred 4 years after surgery, were consistent with overdose (acute combined drug toxicity). Among the adults, three died of early complications of surgery, one died of colon cancer, one of suicide, and the cause of death in the two remaining cases was unclear. Adolescents experienced a greater rate of abdominal reoperations than the adults (19 vs. 10 reoperations per 500 person-years). As a possible explanation for this, the authors offer: “…closer monitoring for complications in adolescent patients and the potential for a lower threshold to reoperate for suspected complications in younger patients, which would lead to the capture of more events.” Nutritional deficiencies were slightly more common in adolescents compared to adults, which the authors attribute to less compliance with recommended… Read More »