Related Posts Plugin for WordPress, Blogger...

Who Benefits Most From Bariatric Surgery?

>> Saturday, March 31, 2012






At this week's ISORAM Boot Camp hosted jointly by the Canadian Obesity Network, University of Alberta, and University of Leipzig (Germany), one of the main topics of discussion was bariatric surgery.  While I was only able to attend a fraction of the week long meeting due to my clinic schedule, I had the great pleasure of hearing several great sessions, including the final lecture provided by Dr Arya Sharma.

Dr Sharma, as always, gave a very thought provoking talk, highlighting several points, ranging from the '4 M's' of obesity assessment and management for clinicians to consider, to the '5 A's' of obesity counseling.  When we overeat, he urged us to consider: are we eating in response to hunger (called 'homeostatic hyperphagia' in medicalese), or for the purpose of reward (aka 'hedonic hyperphagia')?

Another of the many topics Dr Sharma explored was the discussion of what type of patient benefits most from bariatric surgery.  He reviewed the 2012 update from the landmark Swedish Obese Subjects (SOS) study for us, which examined the long term effect of obesity surgery on heart attacks and strokes, compared to control patients who did not have obesity surgery.  While the study did show a lower rate of cardiovascular events and cardiovascular deaths in the group that had obesity surgery, it took nearly two decades of study for this difference to emerge.  As the SOS study participants were obese but otherwise quite healthy, thissuggests that body mass index (BMI) alone may not be an appropriate criterion to decide who is the most appropriate candidate for obesity surgery.  As has been suggested by many studies since the SOS study began, it may be more prudent to select patients based on whether they have complications of their excess body weight (eg diabetes, severe hypertension, etc), as there may be greater health benefits to be had for these individuals.

Interestingly, the SOS study also found that it didn't matter how high the patient's starting weight was, nor did it matter how much weight the patient lost by having obesity surgery - the reduction in risk was the same.  Again, this suggests that body weight or BMI alone is probably not the best way to decide who stands to benefit most from bariatric surgery - an assessment based on the presence or absence of complications of excess body weight (ie the EOSS staging system) may be far more appropriate.

Congratulations to the CON on another hugely successful meeting!


Dr Sue Pedersen www.drsue.ca © 2012 drsuetalks@gmail.com

Follow me on Twitter for daily tips! @drsuepedersen 

Read more...

The Vote is In but the Jury is Out - Is Bariatric Surgery Appropriate for the Treatment of Type 2 Diabetes?

>> Thursday, December 8, 2011







At this week's World Diabetes Congress in Dubai, hosted by the International Diabetes Federation, I had the opportunity to listen to a fantastic debate as to whether bariatric (weight loss) surgery is an appropriate treatment option for Type 2 Diabetes. 

The argument in favor of bariatric surgery was presented by Dr Francesco Rubino, a bariatric surgeon and leading authority on the issue from Cornell University, in New York.   He highlighted key points of evidence regarding the benefits of bariatric surgery in terms of improving diabetes, noting that bariatric surgery provides a powerful potential opportunity to reverse the course of an otherwise progressive disease.  While the current criteria for bariatric surgery in diabetics include a Body Mass Index (BMI) ≥35, he presented for us the International Diabetes Federation position statement on the role of bariatric surgery, which suggests that surgery should also be considered in people with BMI 30 to 35 when diabetes cannot be adequately controlled by medical therapy, especially in the presence of other cardiovascular risk factors.  (BMI can be calculated here)

Dr Rubino noted that bariatric surgery stands apart from some other medical treatments of diabetes, in that many medications cause weight gain, whereas bariatric surgery can result in substantial weight loss.  He noted that patients who are most likely to have the greatest improvement (or complete remission) of diabetes include those with a shorter duration of diabetes, and lower preoperative medication requirements; in other words, earlier intervention appears to produce the best results.  He noted that not only does bariatric surgery improve diabetes, but can also be very effective to prevent new cases of diabetes.  Other benefits include some improvement in cholesterol profile and blood pressure, which are also risk factors for cardiovascular disease.  Gastric bypass is superior to gastric banding in achieving these effects.  (Sleeve gastrectomy was not discussed in particular - I enter my own editorial comment here, that sleeves are proving to be quite effective to treat type 2 diabetes as well, somewhere between gastric bypass and banding in terms of efficacy, but so far appearing to be closer in efficacy to gastric bypass).

In discussion of the very limited accessibility to bariatric surgery, Dr Rubino provocatively noted:

"If there were a pill or a shot that can control blood sugars, improve body weight, cholesterol and blood pressure, and improve survival, would it be acceptable that >99% of people do not have access to the treatment? "

He concluded with the comment that we should not be using BMI as the most important criteria or cutoff in choosing the right patient for bariatric surgery; rather, we should be considering the metabolic disease (in particular, diabetes) that each patient carries, and stratify our decision re surgical candidates based on cardiovascular risk profile, as the BMI does not tell the whole story.   

The negatives for bariatric surgery in the treatment of type 2 diabetes was presented by Dr John Pinkney, professor of diabetic medicine from Plymouth, UK. 

Dr Pinkney opened with a discussion of the treatment goals for type 2 diabetes, including increasing life expectancy, reducing cardiovascular disease, reducing small vessel complications of diabetes (eye, kidney, and peripheral nerve complications), and improving quality of life, using treatment modalities where the benefits exceed the risks.   Many of these health goals are achieved by optimizing control of vascular risk factors (diabetes control, blood pressure, and cholesterol).

In terms of treatment targets for diabetes, Dr Pinkney notes that several recent diabetes trials have suggested that tight glucose control may not actually prevent cardiovascular events, compared to slightly less tight glycemic control.  He wondered, then, whether getting diabetes into excellent control with bariatric surgery would really be of that much benefit (and worth the risk?) in patients who had reasonable control of their diabetes in the first place. 

He noted that while the improvements in blood pressure and cholesterol with bariatric surgery are statistically significant, that the absolute improvements are not that big.  From the prevention of small vessel diabetes complications perspective, he noted that there is not yet much study in this area, and the question as to whether bariatric surgery prevents these diabetes complications in the long term remains unanswered. 

While improvements or remission of diabetes is certainly impressive, the long term durability of diabetes remission was discussed, in that the most recent literature is now suggesting that a substantial proportion of diabetes that initially goes into remission, recurs years down the road.

The downsides of bariatric surgery require very serious consideration, and the risks vs benefits must be weighed carefully.  The risk of death due to the surgery itself was discussed, though Dr Rubino noted that this risk is approximately that of a gall bladder removal surgery (ie, fairly low as far as surgeries are concerned).  Although the need for diabetes medications may decrease with surgery, these treatments are 'traded in' for the need for a new array of lifelong nutritional supplements (the exact array of supplements needed depends on the type of surgery).  Not taking these supplements or not having them monitored carefully can result in life threatening complications.  The removal of the freedom to 'eat as I wish' and the potential impact on quality of life was also noted.

Dr Pinkney noted that type 2 diabetes is a complex disease that is very common, and suggested that it may not be feasible or productive in general to consider a treatment (surgery) that is very expensive, requires lifelong follow up, and is therefore not accessible for any but a small sliver of the people with diabetes worldwide.

Both presenters were grateful for the opportunity to present this important topic, noting that the topic of bariatric surgery has only been taken seriously as a potential therapy for diabetes in the last few years.

At the conclusion of the presentations, a show of hands of the audience was requested as to how many people were in favor vs against the use of bariatric surgery to treat type 2 diabetes (this was an auditorium containing several hundred diabetes health care professionals from around the world) - to my eye, the vote was roughly evenly split. 

My feeling on this issue is reflected in an underlying theme to both of these presentations: the decision for bariatric surgery is a highly patient specific decision.  Each patient must be considered on a case by case basis, with the benefits and risks carefully weighed and discussed in exquisite detail.  For the right diabetic patient, bariatric surgery can provide an appropriate treatment option.


Dr Sue Pedersen www.drsue.ca © 2011 

drsuetalks@gmail.comFollow me on Twitter for daily tips! @drsuepedersen  

Read more...

Genetics Influence Response of Body Weight to Gastric Bypass Surgery

>> Saturday, October 15, 2011





Gastric bypass surgery is an increasingly utilized treatment option for severe obesity worldwide.  While this surgery can be very successful to result in substantial and sustained weight loss over the long term, individual results from person to person are highly variable.  A recent study suggests that a person's genetics may be the primary factor responsible for this variation.


The study, just published in the Journal of Endocrinology and Metabolism by Ida Hatoum and colleagues, examined the DNA of 848 patients undergoing gastric bypass surgery at the Massachusetts General Hospital.  Amongst these patients were 13 pairs of first degree relatives, none of whom were living together.  An additional 10 pairs of patients were identified who were living together but not related (thus allowing a comparison of the effect of environment on the efficacy of surgery). The remaining 794 people in the study were randomly paired for a non-genetic, non-environmentally connected comparison group.  

Interestingly, the study found that first degree relatives had a similar response to surgery, with an average of only 9% difference in the excess weight lost between members of each pair.  In contrast, there was a 26% difference in excess weight lost between cohabitating, unrelated individuals, which was no more similar than unrelated randomly paired individuals, who had a 25% difference in excess weight.

These results suggest that genetics have a strong influence on the effect of gastric bypass surgery on body weight.  Interestingly, they also suggest that the home environment does not have an influence on the efficacy of gastric bypass surgery.

We are certainly becoming increasingly aware of the strong genetic influence in obesity.  Dozens of genes which contribute to obesity risk have been identified so far, and this number continues to climb as our knowledge base grows.  It is therefore perhaps unsurprising to learn that genetics play a strong part in the response to bariatric (weight loss) surgery as well. 

The current study examines the influence of genetics on the lowest weight reached (called the 'nadir') after gastric bypass.  I would be very interested to know if genetics has an equally strong influence on the risk of weight regain after hitting the nadir weight postoperatively, as there is also quite a substantial variation in weight maintenance vs weight regain in the long run after bariatric surgery.  More study is needed in this area.

Although this study was too small to be able to identify the specific genetic contributors to weight loss success after gastric bypass surgery, larger scale studies could be undertaken to examine the entire human genome to try to identify the relevant genes.  It is likely that there are many genes involved here, and their interactions are likely to be extremely complex.  Discovery of new genetic mechanisms involved in the response to surgery may teach us something not only about surgery but about obesity in general, possibly leading us down the path to other discoveries that will assist us in non-surgical treatment of obesity as well.  

As for people currently contemplating gastric bypass surgery, this study is too small to make definitive conclusions, but if you have a first degree relative (parent, sibling, or child) who has had the surgery, the success they experienced may be predictive of your own.


Dr Sue Pedersen www.drsue.ca © 2011 drsuetalks@gmail.com

Follow me on Twitter for daily tips! @drsuepedersen

Read more...

Chatelaine Interview: The Latest News and Research in Obesity

>> Saturday, August 6, 2011






A few months ago, I was asked to provide an overview of the undertakings at this year's Canadian Obesity Summit in Montreal, by James Fell, fitness columnist, certified strength and conditioning specialist, and the man behind Body For Wife.  

The complete article can be found at this link.  Below are some excerpts regarding elements of the Summit that I felt were important to highlight.  As some very controversial issues were raised and discussed, I thought I would post these items, and I'd really like to survey my readers as to their thoughts on these issues!  Please feel free to post a comment by clicking on the envelope icon at the bottom of this post - this is how we can get a good dialogue going, and stimulate change in our society! 


1. Genetics: “There are least 45 obesity-related genes that have been discovered and each one contributes 2-3kg to body weight. We don’t understand a lot about how they work; some create a different balance in hunger hormones and others cause fat storage. It’s not that some people are genetically fixed to be obese, but it can set the stage.”

Dr. Pedersen also mentioned how a woman who is obese while pregnant increases the prevalence of the child being obese through epigenetic changes that take place in utero.


2. Environment: “There was a lot at the conference about guiding Canadians to lead healthier lives. For example, should there be a junk food tax? Can we create programs to get Canadians to focus on weight loss and healthy eating and getting more exercise?”


3. Childhood obesity: “Eight percent of Canadian adolescents are obese, so how do we create good family-based programs to help them lose weight? These have to be focused on the parents because if they lose weight, then the kids lose weight by default.” 

Sue also had some interesting comments about adolescents and bariatic surgery. “Lap banding is favoured in kids [in extreme cases where it is deemed necessary] because it is the least invasive and is reversible. The Hospital for Sick Children in Toronto is the only place in Canada that is doing it right now. The decisions for bariatric surgery with children are very challenging.”


4. Adult obesity management: “There was a big focus on weight-loss surgery for people with Type 2 diabetes because the surgery can put it into remission. Having the surgery is done when the benefits of it outweigh the risks. Bariatric surgery can be the appropriate decision for a patient who has failed in all other attempts to lose weight.” Dr. Pedersen stated that such patients require psychological counseling as well, and that this is never a decision to be entered into lightly.

In regards to bariatric surgery, there is not enough funding so the wait list is about five years. Some provinces allow people to pay for it themselves, allowing lap banding for about $16-20 thousand for those who don’t want to wait.


Dr. Sue © 2011   www.drsue.ca     drsuetalks@gmail.com

Follow me on Twitter for more tips! drsuepedersen

Read more...

Should Adolescents Have Bariatric Surgery?

>> Saturday, May 7, 2011







Obesity is a serious problem amongst all age groups, and we are seeing obesity affect younger individuals in higher numbers.  It is estimated that18% of American adolescents and 9% of Canadian adolescents are obese.   In adults, bariatric (weight loss) surgery is increasing recognized as an important treatment option for adults who suffer from severe or complicated obesity, in whom all other treatment options have been unsuccesful.  As such, the question is being raised as to whether adolescents with severe obesity should be considered for weight loss surgery.


This complex issue was discussed at the Canadian Obesity Summit last weekend in Montreal.  I had the pleasure of hearing several speakers from both the US and Canada, sharing their experiences on this issue.


Dr Evan Nadler, pediatric surgeon at the George Washington University School of Medicine & Health Sciences, discussed the various types of weight loss surgeries and the known data to date.   So far, preliminary evidence suggests that lap banding may be the most appropriate surgery to consider in this age group.  Early data suggests that the risks of gastric bypass surgery may be unacceptably high amongst teens, and there is little data regarding sleeve gastrectomy.  All three of these surgeries are being actively studied.


Dr Jill Hamilton, pediatric endocrinologist at the Hospital for Sick Children in Toronto presented the STOMP (SickKids Team Obesity Management Program), an innovative program which provides multidisciplinary support to adolescents with obesity, and for the appropriate candidate, bariatric surgery.  Five patients have been operated so far (with the first ones being done in October 2010), and this is the only pediatric Canadian site that is currently exploring this area.


Dr Beth Dettner, PhD and psychologist who works with the adolescents in the STOMP program, provided a poignant review of the psychological complexities of this population.  There are several challenges involved in selecting the appropriate teen for bariatric surgery: assessing for psychological conditions like depression, anxiety, and eating disorders, assessing family functioning and support for surgery, patients' and parents' understanding of the surgery and required diet and activity behaviours, the teen's coping skills, and their motivations for surgery are all key components.   


I found this to be an absolutely fascinating workshop, and I have a deep and renewed respect for the challenges that face adolescents with obesity, and their health care professionals as they work with these patients to find the most appropriate and successful treatment options.  Elements ranging from the high prevalence of binging and purging behaviours (as high as 30%), to the potential impact of gastric bypass surgery on accrual of peak bone mass, to the possibility of parental coercion to have the surgery, to the challenges of compliance with follow up, to specific motivations for desired weight loss (and the list goes on) all need special consideration in this population, and must be very carefully weighed against the potential weight, health, and psychosocial benefits that can result from successful bariatric surgery.


Dr. Sue © 2011   www.drsue.ca     drsuetalks@gmail.com

Follow me on Twitter for more tips! drsuepedersen

Read more...

FDA Gives Thumbs Up to Broader Lap Banding Indications While Research Gives Thumbs Down to Long Term Outcomes

>> Saturday, April 16, 2011






For some individuals, despite intensive and longstanding attempts at shedding pounds and exhausting every possible lifestyle intervention or medical therapy, weight loss remains elusive.  In some cases, weight loss surgery (called 'bariatric' surgery) may be the most appropriate option.  Bariatric surgery has typically been reserved for the most extreme cases, but recently, the American FDA has lowered the Body Mass Index (BMI) requirements for eligibility to undergo laparascopic adjustable gastric banding ('lap band') surgery.


As blogged previously, bariatric surgery has traditionally been reserved for the most serious cases of obesity, defined as a Body Mass Index of 40 or greater, or, a BMI of ≥ 35 with one or more serious complication of obesity, such as diabetes, obstructive sleep apnea, or high blood pressure (you can calculate your own BMI in the right hand column here).  However, because of the impressive success that bariatric surgery can have to result in weight loss and reduce complications of obesity, the FDA has lowered the required BMI for a patient with a serious complication of obesity to 30 for the lap band procedure.

However, as blogged previously, recent study suggests that lap banding may actually have a poor long term outcome.   It is interesting that the FDA seems to be embracing the most extreme of obesity treatments by expanding indications for bariatric surgery, in a form that may be associated with poor long term outcomes, while simultaneously (and in some experts' opinions, perhaps stringently) rejecting a lineup of three potential new weight loss medications in the last year.


For Canadians, the BMI criteria for bariatric surgery remain unchanged.  If we were to follow our US counterparts with a broadening of the BMI criteria, it would make little practical difference in any case, as the average wait time for bariatric surgery across Canada is over half a decade.  In addition, in light of recent study suggesting that lap banding may have a poor long term outcome, other types of bariatric surgery (such as gastric bypass) may be more appropriate to consider, though these other forms of surgery have a significant risk of complications as well, and long term outcomes of these procedures are not yet well known. 


Dr. Sue © 2011   www.drsue.ca     drsuetalks@gmail.com

Follow me on Twitter for more tips! drsuepedersen

Read more...

Bariatric Surgery - Patient Guide to Endocrine and Nutritional Management

>> Saturday, November 6, 2010





As blogged previously, bariatric (weight loss) surgery is a treatment options for people with severe obesity that has proven to be resistant to treatment with more traditional and conservative measures. The treatment does not end with the surgery itself, however - the story is far more complex than that.

As beautifully summarized in the Patient Guide to Endocrine and Nutritional Management after Bariatric Surgery in the Journal of Clinical Endocrinology and Metabolism (a free download!), there are several aspects which require close attention and follow up in order to minimize the chance of weight regain after surgery, to minimize the risk of developing a complication of bariatric surgery, and to ensure that complications of obesity are well managed postoperatively.

To decrease the chance of weight regain after surgery, a lot of the preventive work actually has to happen before the surgery is even done. It must be recognized, as with any 'diet', that the lifestyle change being made has to be a permanent one. This is not about eating smaller portions or altering food choices for a short period of time - this is forever. It is also absolutely critical that the relationship with food is thoroughly explored and managed well before the surgery takes place. There are many contributing factors to overeating, many of them emotional: eating in sadness, in joy, to comfort, to alleviate stress, even to service a true addiction to food. People who have not had help in dealing with these aspects of their weight struggles, or who have not worked through these issues prior to surgery, are not appropriate candidates for bariatric surgery, as they stand a high risk of weight regain postoperatively if those habits and coping mechanisms are not managed beforehand.

The risk of nutritional deficiencies is very real after bariatric surgery, particularly after gastric bypass surgery (pictured above), which involves a re-routing of the small intestine such that about 1.5 meters of small intestine is no longer exposed to food and the enzymes required to digest it. Patients who undergo gastric bypass surgery are at risk of life threatening complications if they do not adhere to their supplement regimen, which for most patients includes a specific multivitamin, calcium, vitamin B12, vitamin D, and often iron. An individual who is committed to having gastric bypass surgery must be equally committed to taking supplementation for the rest of their lives. Protein malnutrition is a potentially severe complication of any type of bariatric surgery due to decreased intake; it is essential to follow the protein consumption recommendations provided by the bariatric program's dietician (usually at least 90 grams of protein intake per day).

Because bariatric surgery often has a profound beneficial impact on several obesity-related complications such as diabetes, high blood pressure, obstructive sleep apnea, cholesterol, and osteoarthritis (to name a few), it is important to have physicians involved both pre- and post-operatively who can help to manage changes in medications and treatment approach that are often necessary.

While bariatric surgery is a very appropriate treatment option for some people, it must always be remembered that bariatric surgery is not a quick fix or a cure; it is the exchange of one set of medical issues for another (though usually in a positive direction), and it is most certainly a permanent lifestyle alteration.

Dr Sue Pedersen www.drsue.ca © 2010 drsuetalks@gmail.com

Follow me on Twitter for daily tips! @drsuepedersen

Read more...

  © Blogger templates Palm by Ourblogtemplates.com 2008

Back to TOP