Obesity Management In Canada - A Long (But Promising!) Road Ahead

At this week's Canadian Obesity Summit meeting, I have had the great pleasure of chairing, speaking, and participating in a diverse array of educational sessions, ranging from studies of lifestyle alterations, to government policies, to medications treating obesity, to bariatric surgery.

One of the themes that rang strong is this:

Canada needs more resources dedicated to the management of obesity. 

I can give you many examples of how this point came out, but I'll give you one that rings out in particular.  One session which discussed bariatric surgery included a fabulous presentation by bariatric surgeon, Dr Mary-Anne Aarts, regarding barriers to post operative follow up of bariatric patients.  An interesting discussion ensued with comments from bariatric care providers across the country, and most agreed that follow up appointment attendance is often not good, particularly the further a patient gets in their post op journey (after 6 months post surgery, patients are usually requested to come to appointments every 6 months until 2 years post op).   One point that was made was that follow up may be perhaps too infrequent to keep patients interested and motivated to continue to come. (Studies do show that bariatric surgery patients enjoy greater success with more frequent follow up.)  Dr Aarts pointed out that in the Netherlands, bariatric patients have appointments scheduled every 3 months for 2 years postoperatively, which shocked most of the audience... who in Canada has the resources for that?!  

Here is our problem.  Obesity is a chronic disease, just like, for example, diabetes - yet, we don't treat obesity like a chronic disease.  The Canadian Diabetes Guidelines recommend that diabetics see a physician every 3 months at least, to have an A1C (diabetes report card) and other elements of their health checked as needed.  Why don't we have the same resources available to treat obesity in the same long term, longitudinal way?  If we asked our patients with obesity to follow up every 3 months with a health care provider on an ongoing basis to help them manage this disease, perhaps they might feel more supported and weight management success might be better.

What we need is to:

1.  Break down the stigma against obesity amongst the general public and health care providers, such that obesity is accepted as a chronic disease and not a lifestyle problem.

2.  Have more resources available in health care such that we are able to manage obesity with a long term, team based approach that engages multiple disciplines including dietitians, nurses, pharmacists, psychologists, exercise therapists, and doctors.

3.  Teach health care providers how to best approach the discussion and treatment of obesity with their patients. (See the 5As of obesity as a great way to start!)


So what's the 'Promising' part in all of this?   We (as the Canadian Obesity Network) are 11,000 members strong, and passionately dedicated to achieving these goals.  Together, we continue to make a difference one step at a time, with the above goals in mind.   This week's Summit has gone a long way to breaking down the obesity stigma in the public eye, and we continue to redouble our efforts as our numbers and voice grow.

PS - the Canadian Obesity Network membership is open to anyone with a professional stake in obesity - and it's totally free to join!  Check it out here!

Looking forward to the last day of the Summit today.

Follow me on twitter! @drsuepedersen

www.drsue.ca © 2015

Read more...

Why Weight Loss Increases Gallstone Risk

As for everything in life, weight loss too has its pros and cons.  While the health benefits of weight loss are numerous and powerful, there is an increased risk of gallstone formation, particularly if the weight loss is fast.

Gallstones are very common, being present in 17% of women and 8% of men (most don't know that they have them!).  Bile, which is the digestive juice made by the liver and stored in the gallbladder, is composed of bile acids, which are made by the liver from cholesterol.  Bile also contains cholesterol, phospholipids, proteins and electrolytes.  The bile is usually able to carry cholesterol produced by the liver out into the intestine in a liquid form, but if the cholesterol concentration gets too high, or the contraction of the gallbladder gets too sluggish, cholesterol crystals develop and gallstones form.

Obesity is a risk factor for gallstones for a number of reasons.  There is a larger pool of cholesterol moving around in the body, and the liver's ability to convert cholesterol into bile acids is impaired (thus, more cholesterol relative to bile acids in the bile).   Gallbladder contractions are also more sluggish in obesity, which may be related to insulin resistance and resistance to a satiety (sense of fullness) hormone called leptin.  Diabetes, prediabetes, use of the birth control pill, and hormone replacement therapy are other risk factors for gallstone disease.  Genetics also play a part in gallstone risk, which is an area that we are just starting to learn about.

Within the first 4 months of moderate weight loss on a diet, the risk of gallstones is as high as 25% (though most of these will be without symptoms).  With faster and larger weight loss, the risk is higher: as many as 71% of patients will have gallstone formation by 1 year after bariatric (obesity) surgery.  About 40% of people developing gallstones after bariatric surgery will have symptoms; for those who don't have symptoms, about half will disappear by 2 years after surgery.

Gallstones form during weight loss because cholesterol content of bile increases during weight loss, as fats are being moved out of fat tissue and being utilized or disposed of by the body.  If calorie intake is too low, bile acid production by the liver may drop as well.  Also, during rapid weight loss, the gallbladder contractions become more sluggish.

So, what are the take home messages here?  Again, remember that the health benefits of weight loss are great and numerous, and far outweigh the potential risk of gallstone formation.  That being said, losing weight at a reasonable rate (max 1-2 lb per week) helps to prevent the higher risk of gallstones that comes with too rapid a rate of weight loss.  For those who will be losing weight quickly with bariatric surgery, your surgeon may recommend that your gallbladder be removed at the time of surgery if you already have gallstones.  If not, a medication called URSO (ursodeoxycholic acid) may be recommended, which has been shown to reduce the risk of gallstone formation after gastric bypass surgery by 60%.

Follow me on twitter! @drsuepedersen

www.drsue.ca © 2015

Read more...

Bariatric Surgery For Diabetes Prevention?

Over the last decades, many modalities to prevent type 2 diabetes have been studied.  Lifestyle changes, particularly if they result in weight loss, can be very powerful to prevent this condition.  Of all of the medications studied, only metformin has so far been recommended to decrease the risk of developing diabetes in people who have prediabetes.  Now, studies are coming out, showing that bariatric (obesity) surgery can be very powerful to prevent type 2 diabetes.

One such study, published recently in The Lancet (Diabetes & Endocrinology),  looked at over 2000 patients who had bariatric surgery, and compared them to a group of matched patients who had not had obesity surgery.  They found that, over a median of 2.8 years and a maximum of 7 years of follow up, patients who had bariatric surgery had an 80% lower risk of developing diabetes compared to people who had not had bariatric surgery.

Another recent study was a systemic review and meta-analysis that looked at the power of different interventions to prevent diabetes. In examination of studies of physical activity +/- diet, anti diabetic medications, obesity medications, and bariatric surgery, they found all of these strategies to be of benefit.  Bariatric surgery stood out as being the most effective to prevent diabetes, with a 90% reduction in risk.

So the question then becomes, should we advocate for obesity surgery for the purpose of prevention of diabetes?  Well, as for any treatment or prevention of any medical condition, it's important to balance the benefits vs risks.  Bariatric surgery is invasive, and the most successful modalities (gastric bypass and sleeve gastrectomy) are permanent procedures.  These procedures have a long list of possible complications that need to be taken into consideration.

While bariatric surgery may be the best treatment option for some patients with obesity and existing type 2 diabetes, obstructive sleep apnea, severe high blood pressure, or severe osteoarthritis, it seems that using surgery solely to prevent these conditions may be outweighed by potential risks.  That being said, a marked reduction in risk of developing type 2 diabetes is certainly an added bonus to the patient having bariatric surgery who is having bariatric surgery for other reasons.


Thanks to my friend Gord for the inspiration for this blog post!

Follow me on twitter! @drsuepedersen

www.drsue.ca © 2015

Read more...

Intestinal 'Condom' For Weight Loss?

Another interesting approach to less invasive obesity/metabolic surgery that is currently being studied is the duodenal-jejunal bypass liner.  This is a temporary 60-cm liner that is delivered into the upper part of the small intestine endoscopically (ie, by putting a camera and insertion equipment down through the mouth).  It is left in place for a number of months, and then removed.  It's sometimes referred to as the 'duodenal condom' in that... well, you can see the resemblance... but both ends are open to allow food to pass through.

The idea behind this is to mimic (in a shorter version) the intestinal component of the Roux-en-Y gastric bypass surgery, where the intestines are surgically rerouted to bypass about the first 150cm of small intestine.  We think (based on studies) that one of the major reasons why type 2 diabetes often improves dramatically after gastric bypass surgery is the hormone changes that happen when the intestine is rerouted in this fashion; therefore, there is a lot of interest in seeing whether the liner would have an effect not only on weight loss, but also on type 2 diabetes.

                             Gastric Bypass Surgery


A clinical trial was recently done on the liner, where 77 patients with type 2 diabetes and obesity were randomized to receive either the liner, or dietary counselling (control group).  After 6 months, patients who had the liner had greater weight loss, better diabetes control, and required less diabetes medication than the control group.

Patients then had the liners removed, and both groups were followed up for an additional 6 months after liner removal, with 66 patients completing the full study. There was some weight regain in the group who had previously had the liner, though at 1 year they still had greater weight loss than the control group.  At 1 year, there was no longer a difference in diabetes control between the groups.

In the short term, it appears that the liner is quite effective to help people lose weight and improve their type 2 diabetes control.  However, removal of the liner has to happen at some point, because the longer the liner is left in, the higher the risk that it can lose its hold and migrate further down the intestine, or cause bleeding or perforation (a hole in the intestinal wall), which are all serious complications.  So far, the liner has been shown to have a low risk of these complications after 6 months, and a few studies have now been published suggesting the risk is also low after 1 year.

The liner's current temporary nature is reminiscent of many of the 'diets' out there - they do nothing to help make permanent lifestyle changes, so after the diet (or the liner) is gone, the likelihood is that weight will be regained, along with its metabolic complications.  It would be interesting if the liner could be left in safely for a longer period of time - I'll be watching this area with interest, as the duration of study is growing.  In the meantime, while the liner's results look good in the short term, I'm not overly enthusiastic about an intervention if it is only temporary.

Follow me on twitter! @drsuepedersen

www.drsue.ca © 2014

Read more...

Vagal Nerve Blockade for Weight Loss?

As severe obesity has proven so difficult to treat, much study is underway to try to find innovative treatment options.

The vagus nerve is thought to play an important role in the feeling of fullness (called 'satiety') and metabolism, so the question has arisen as to whether blocking this nerve could help to treat obesity.
An interesting study recently reported in the Journal of the American Medical Association (JAMA) was published, evaluating whether intermittent blockade of the vagus nerve would be effective to induce weight loss.

This study was a randomized, controlled trial of 239 patients with a Body Mass Index (BMI) between 35-45, where an electrical device was implanted to intermittently block the vagal nerve in half of the patients, and the other half had a 'sham' surgery (meaning they went through the implantation procedure, but the device was not hooked up to the vagus nerve).  All patients received lifestyle counseling.

They found that at 1 year, the vagal blockade patients lost a little more weight (3.2%) than the control group, but the vagal blockade group also had a higher risk of serious adverse events (8.6% vs none in the control group). Interestingly, the control group, with lifestyle counseling only, lost 6% of their body weight (compared to 9.2% in the vagal blockade group), showing that lifestyle counseling alone (plus a possible placebo effect of the sham surgery) can result in substantial weight loss.

So, based on this study, intermittent vagal nerve blockade doesn't seem like a promising option - weight loss benefits are minimal, and the rate of serious adverse events is concerning.

Follow me on twitter! @drsuepedersen

www.drsue.ca © 2014

Read more...

Bariatric Surgery - More Long Term, High Quality Data Needed

Based on the available evidence, bariatric (obesity) surgery is effective to improve upon complications medical conditions related to obesity (such as type 2 diabetes and sleep apnea) and helpful for weight loss.  However, most of this data is based on shorter term results, and there is a concern regarding gaps in high-quality knowledge as to the benefits and risks of bariatric surgery over the long term.

In a recent literature review by Puzziferri and colleagues in Journal of the American Medical Association,  the current status of long term high quality data in bariatric surgery research was assessed.  They examined the literature to see just how much high quality longer term data is out there (defined as studies of 2 years or more, with follow up data on at least 80% of patients by the 2 year mark).

They found that only 29 studies total (less than 3% of studies identified) had 80% or more of patients followed up past the 2 year mark (7,971 patients total).  On analysis of available data in these studies, they found that the average excess weight loss was 66% for gastric bypass surgery, vs 45% for gastric band.  Type 2 diabetes remission rates (based on 6 studies) were 67% for gastric bypass, vs 29% for gastric band.  Remission of hypertension (high blood pressure, based on 3 studies) was 38% for gastric bypass and 17% for gastric banding. There wasn't enough data to analyze these parameters for sleeve gastrectomy.  No study had data past 5 years.  Concerningly, only half of the studies reported on complications at least 2 years after surgery.

So, while the existing high quality long term data is encouraging, we are still lacking in quantity of good quality data (clinical trials with low long term dropout rates) to have a thorough understanding of long term effects of bariatric surgery.  While we do have encouraging observational studies to guide us on longer term benefits vs risks of bariatric surgery (encouraging particularly for gastric bypass surgery and sleeve gastrectomy), randomized controlled clinical trials ideally need to be done and patients followed long term (with less dropouts) to have a more comprehensive understanding of long term effects.

The above being said - as discussed in a recent study by Courcoulas and colleagues, and as I can certainly attest to from my own research experiences - this is a tall order to fill.

Follow me on twitter! @drsuepedersen

www.drsue.ca © 2014

Read more...

A Different Kind of STAMPEDE

Obesity (bariatric) surgery has become accepted as an option for the treatment of type 2 diabetes by most diabetes guidelines around the world. The data on which these recommendations are based are from shorter studies, from weeks to months to up to 2 years. 

Now, in a landmark randomized controlled trial published in the New England Journal of Medicine, 3 year data shows us that the benefit of bariatric surgery to diabetes control is sustained out to at least 3 years.

The study, called the STAMPEDE study, randomized 150 people with type 2 diabetes, to receive either intensive medical treatment of diabetes alone (with a goal A1C of 6.0%), vs medical treatment plus gastric bypass surgery, vs medical treatment plus sleeve gastrectomy.

The study clearly shows that gastric bypass surgery and sleeve gastrectomy are superior to intensive medical therapy alone, to have control of type 2 diabetes at 3 years. Thirty-eight percent of patients who had gastric bypass surgery had tight control at 3 years, compared to 24% after sleeve gastrectomy, compared to only 5% receiving medical treatment alone. (The difference between the gastric bypass and sleeve groups was not statistically significant.)

With the above being said, I do take issue to how this study was structured, in that the goals for control of diabetes were too tight. We no longer recommend an A1C of 6.0% as a goal, as another landmark study (the ACCORD study) showed that control this tight was associated with an increased risk of death. It would be interesting to know how the numbers would have panned out if the commonly accepted A1C target of 7.0% was used instead.

However, the point of the article remains that gastric bypass and sleeve gastrectomy results in control of type 2 diabetes in significantly more patients than medical treatment alone. There is no doubt that Bariatric surgery is an important tool in our toolbox of diabetes therapy in the 21st century.

Follow me on twitter: @drsuepedersen

www.drsue.ca © 2014

Read more...