Feeds:
Posts
Comments

Posts Tagged ‘bariatric surgery’

Interesting article over at Medscape on the role of bariatric surgery in the treatment of non-alcoholic fatty liver disease (NAFLD) and (NASH).

For the uninitiated, non-alcoholic fatty liver disease is a serious condition where functional tissue of the liver (used to metabolize and detoxify everything we ingest including medications) is replaced with fat tissue, and eventually fibrosis.  As more and more healthy tissue becomes fatty & fibrotic, the liver function deteriorates until it progresses to cirrhosis and eventual liver failure.

Currently, the only treatment for cirrhosis and liver failure is liver transplantation (which is still only a temporary measure, even in the best case scenarios*.)

But why is the happening?  and who does it affect?  Obesity and obese patients.

To better understand what’s going on – we need to review some basic pathophysiology:

First, lets look at food.  Not in cultural or psychosocial way, or even in food preferences, but food as the body sees it: Fuel for all of our cellular functions.  Just as we run our houses, appliances and cars on different types of fuel – gasoline, natural gas, electricity etc.  our body runs on different types of fuels (proteins, fats, sugars) that all get broken down to serve as energy.  Like fossil fuels – the metabolism of each of these fuels requires different mechanisms (ie. gas-powered versus electric cars) and creates different by-products.

Now I want you to think of a scale.

No, not this kind of scale

No – I want you to think of a scale, as in a delicate balance between differing metabolisms for different fuels.

Think of a multi-tiered scale, where a delicate balance between the types of metabolism and waste products is required for continued good health – anything that upsets the balance such as diabetes – throws everything out of whack.

Normally, as fuel (food) in consumed – the body uses insulin to transport the fuel into the cell for processing (metabolism), so think of insulin as a wheelbarrow carrying in complex carbohydrates (sugars) into the cell.

Now, in a person with obesity & diabetes – two things are occurring – too much fuel and not enough wheelbarrows**.  These means that:

1.  Excess fuel is converted into fat (adipose tissue – which we are all familiar with).

2.  Without the wheelbarrows, the body has to find another way to break down the fuel.  This other pathway – for fat metabolism has a lot of by-products  – namely free fatty acids (cholesterol and triglycerides.)  This leads to numerous problems (hypercholesterolemia and cardiovascular disease for one), and fatty liver disease.

(This is a gross oversimplification of a series of very complex mechanisms, but for today’s discussion – it is sufficient.)

Just as the rates of obesity, and diabesity (diabetes caused by obesity) have skyrocketed, so has cardiovascular disease (which we’ve talked about before) and the prevalence of non-alcoholic liver disease. In fact, the authors of the study below found that 70% of the people with a BMI greater than 35 have some degree of non-alcoholic liver disease, and over 30% have the more severe form – NASH.

The article by Rabl & Campos (2012) looks at the literature on the outcomes (progression or regression of disease) after bariatric surgery in patients previously diagnosed with NAFLD.  (I’ve linked a pdf version of the entire article under the full reference.)

They looked at the current bariatric procedures including the ever popular lap-band procedure and it’s effectiveness in treating NAFLD. What they found was that in the majority of cases – with certain procedures (formal gastric bypass surgery aka Roux en Y, and biliopancreatic diversion procedures) the disease process was not only halted, but regressed as a result of both weight loss, and a reversal of altered metabolism.  They also found that as a result of a reduced stomach surface area (in comparison to lap-band procedures where the stomach remains intact) – reduced ghrelin leads to increased weight loss.

(If you don’t know about ghrelin – think of it as an evil gremlin (the one that makes you want cookies when you know you are about to eat dinner) – since it is a potent appetite stimulant produced by the stomach.  The larger the stomach – the more ghrelin released – so the surgical procedures such as gastric bypass where a portion of the stomach is actually surgical removed are significantly more effective overall that lap-banding procedures.)

This is a significant advancement for medicine and the treatment of obesity related disease – since as we suggested above, multiple authors including Burianesi et. al (2008) suggest that the true prevalence of non-alcoholic fatty liver disease is much higher than we realize, (thus affecting a lot more people.)

Notes

* There is a tendency in American society to ‘gloss over’ many of life’s harsh realities, and no where is this more evidence than in the public perceptions of organ transplantation as a ‘cure’ or permanent solution for organ failure.  Transplanted organs do not have the same life expectancy as native organs (even in the best case scenarios) – and for most people who need non-kidney transplants – they get one opportunity, not multiple.  Transplanted organs last ten years – maybe fifteen at the outside – so this is not a cure (particularly in young patients).  Transplantation also carries a whole host of other problems with it – such as the development of opportunistic infections and cancer from the drugs used to prevent rejection, or rejection itself.  The very drugs used to prevent rejection of some organs may cause failure of others – so relying on transplantation as a ‘cure’ for a disease that is becoming more and more prevalent is a pretty poor strategy.

** This balance between mechanisms can be upset in other ways – by starvation, for example, when the body starts catabolizing proteins..  Catabolizing – think cannibalism – as the body consumes it’s own muscle tissue because there is nothing left for it to eat, after it has exhausted all other sources of fuel.

References and Resources

Rabl, C. & Campos, G. M. (2012)  The Impact of Bariatric Surgery on Nonalcoholic Steatohepatitis. Semin Liver Dis. 2012;32(1):80-91 [Article under discussion above].

Body Mass Index calculator – West Virginia Dietetic Association.

Bugianesi et. al. (2008).  Clinical update on non-alcoholic fatty liver disease and steatohepatitis. Annals of hepatology, 2008; 7 (2): April – June 157-160.  The authors ask, “What is the real prevalence of disease?”

Goldstein, B. J. (2001) Insulin Resistance: Implications for Metabolic and Cardiovascular Diseases.  This is a good presentation that explains how alterations in glucose metabolism (from diabetes) affects fat metabolism.

Overview of NASH/ NAFLD with classifications, diagnostics, prognostics : University of California, San Diego – Dan Lawson, 2010 [notes]. Good reference for medical students, health care professionals wanting a brief review.

Salt, W. B. (2004).  Nonalcoholic fatty liver disease (NAFLD): A comprehensive review.  J Insur Med, 2004; 36: 27 -41.

For more about Bariatric surgery – including the Pros & Cons

Advertisements

Read Full Post »

well, I guess we all knew what was coming next.. There was no way I could really stay still – and not interview some more surgeons while I was down here. So I thought I would start with two more specialities that are near and dear to my heart – and those of my readers; cardiac surgery and bariatric surgery.

I will be talking to Dr. Vasquez – who you may remember from a previous post (during an earlier visit to Mexicali) and Dr. Horatio Ham, a bariatric surgeon who also hosts the radio show, Los Doctores on 104.9 FM.

Read Full Post »

As my loyal readers know, I do my best to try to give fair and balanced depictions of surgical procedures, as well as reviews of medical and surgical news and research.  Over at Medscape.com – there is a new video discussion by Dr. Anne Peters, MD.  Dr. Peters is an endocrinologist and a certified diabetic education.  In this video – she talks about the realities of bariatric surgery, and these are things I think that people need to hear.

For more on Bariatric surgery – see my other posts

One of the points that she makes, is (in my opinion) critical.  While bariatric surgery has been shown to cure diabetes in many individuals – there is no medical/ surgical or other treatment to cure much of the pathology related to the development of obesity in the first place.  Obesity is more than poor dietary and exercise habits – it is a psycho-social and cultural phenomenon as well.

For people who don’t want to go to the Medscape site – I have re-posted a transcript of the video from Medscape.com below.

Bariatric Surgery a ‘Magic Bullet’ for Diabetes?

Anne L. Peters, MD, CDE

Transcript
Hi. I’m Dr. Anne Peters from the University of Southern California. Today I’m going to talk about the role of bariatric surgery in the treatment of type 2 diabetes.

There have been a number of recent studies that show just how good bariatric surgery can be for patients with type 2 diabetes.[1,2] In many cases, it seems to cure type 2 diabetes (at least for now), and I think it is an important tool for treating patients with obesity and diabetes.

However, I also have concerns about bariatric surgery, concerns that go back for years as I watched its increased use. When I was a Fellow, I developed a sense of the benefit of extreme caloric restriction for the treatment of type 2 diabetes. I will never forget the first patient I had, an extremely obese man with type 2 diabetes who was on 200 units of insulin per day. His blood sugar levels remained high no matter what we did. He was a significant challenge in terms of management.

One day, he got sick. I don’t remember how or why he got sick, but he ended up in the hospital and I thought that his management would continue to be incredibly difficult. In fact, it was miraculously easy. Within 2 days, he was completely off of insulin and his blood glucose levels remained normal for the entire time he was in the hospital.

This was only a short-lived benefit, however. After he was discharged, he went back to his old habits. He started eating normally, regained the weight, and went back on several hundred units of insulin per day. But it really impressed me how acute severe caloric restriction could, in essence, treat type 2 diabetes.

I have seen many overweight and obese patients with diabetes over the years, and I have seen the frustration as patients go on drugs (such as insulin) that are weight-gain drugs, and they keep gaining more weight. Although I am a big advocate for lifestyle change, many patients can’t do much better. They can’t lose appropriate amounts of weight by their own will or through weight loss programs, or increase their exercise. Therefore, bariatric surgery remains a reasonable option.

For many of my patients who have a body mass index > 35 and type 2 diabetes, I recommend that they at least consider bariatric surgery. Interestingly, very few of my patients actually go for the procedure and I ponder why this is. In part, I think it’s because of the initial evaluation, when you are told what bariatric surgery is like and how much you have to change your habits after the procedure. Before surgery, you are eating however you want to eat and, although you may be trying to diet, there is no enforcement of that diet. After surgery, you have to change how you eat, the portions you eat, and when you eat. I know that people feel fuller, and this is a lot more than just changing one’s anatomy. I think there are significant changes in gut hormones that regulate appetite and satiety. Nonetheless, it is a big change, and many people don’t want to change their habits that much. I know I would be somewhat leery if I were to undergo a surgical procedure that would change my whole way of being. For lots of people, food has many different associations. It’s not just caloric intake; it’s festival, it’s party, it’s joy, it’s sadness. It’s something people like to do, and it hasn’t a lot to do with just maintaining a positive or neutral caloric balance.

I find that people are reluctant to change, and that is understandable. We also don’t know the long-term complications of the procedure. As an endocrinologist, I see 2 things. First, I tend to get sicker patients, so my patients who are on insulin when they undergo bariatric surgery may not get off insulin entirely. They become very disappointed because they think that bariatric surgery will cure them of their diabetes. I also see patients who are too thin, who are nutritionally deficient, who have severe hypoglycemia, or who have significant issues from the surgery itself. In some cases, these patients have needed a takedown of the surgical procedure, restoring them back to their native anatomy.

I think of bariatric surgery as a tool. It is one of many ways to treat our patients with type 2 diabetes. I am a little concerned because we don’t have long-term follow-up data. I think that all bariatric surgery programs, in addition to doing a very thorough preoperative evaluation and counseling, need to do long-term, lifelong follow-up of these patients to see how they do, to see if their obesity returns. In many cases, this does happen. [Patients need to be followed up] to see what happens to their lipids, their blood pressure, and their blood sugar levels over time, and to monitor for other complications.

I think [bariatric surgery] is something that we need to recommend to our patients, and for those in whom it’s appropriate, it is a reasonable step. This has been Dr. Anne Peters for Medscape.

 References
  1. Mingrone G, Panunzi S, De Gaetano A, et al. Bariatric surgery versus conventional medical therapy for type 2 diabetes. N Engl J Med. 2012 Mar 26. [Epub ahead of print]
  2. Schauer PR, Kashyap SR, Wolski K, et al. Bariatric surgery versus intensive medical therapy in obese patients with diabetes. N Engl J Med. 2012; Mar 26. [Epub ahead of print]

Life after Bariatric Surgery

There is also an excellent article by two nurse practitioners about the long-term interventions and health monitoring needed for wellness promotion and health maintenance after bariatric surgery.  While this article is written for other health care providers – it gives an excellent look at life after bariatric surgery, as well as an overview of the surgical techniques, pre-operative evaluation and anticipated post-operative outcomes.

Thomas, C. M. & Morritt Taub, L. F. (2011).  Monitoring and preventing the long-term sequelae of bariatric surgery.  J of the American Academy of Nurse Practitioners, 2011, 23 (9).

Read Full Post »

A full year after we reported it here (and several years after initially being reported in the literature), mainstream media has finally picked up the story about gastric bypass surgery for the definitive treatment of diabetes.   The story made all of the heavies; the Washington Post, the Wall Street Journal, and the Los Angeles Times.

Unfortunately, all of these outlets seem unaware of the existing literature in this area – these results while encouraging, are not surprising.  Similar results have been demonstrated in several other (but smaller) studies for the past ten years, which led to previous recommendations (last summer) for the adoption of gastric bypass surgery as a first-line treatment for diabetes in obese patients.

The publication of two new studies showing clear benefits for diabetics undergoing bariatric surgery has brought this news to the forefront.  In both of these studies, diabetic patients were able to stop taking oral glycemics and insulins after surgery within days..

As this front page story from the New York Times notes – these results do not apply to the more widely marketed ‘lap-band.’  This comes to no surprise to dedicated followers at Cartagena Surgery, who have been reading articles on this topic since our site’s inception in late 2010.

You heard it here first.  For more information on this topic, see our tab on Diabetes & Bariatrics under the ‘surgery’ header. We’ve included a small selection from our archives here.

Bariatric surgery headlines – August 2010

Gastric bypass surgery gets the international federation of diabetes approval.

Gastric bypass as treatment for diabetes

Read Full Post »

Ironically, just a few days ago we were talking about lung cancer and discrimination against patients with lung cancer in the post, The Pearl Ribbon.   Now a new article published in Physicians Money Digest,  suggests that one of the latest trends is discrimination against the obese.  As obese people can tell you – this discrimination has always existed in some form, and from all avenues in society including medicine.

However, this new trend consists of doctors avoiding accepting obese patients in their practice, mainly to avoid the increased workload related to obesity related complications.  That’s right – as discussed in the article by Laura Mortokowitz, which I have re-posted below -some doctors are avoiding caring for obese patients because they do not want to provide care to patients with higher risks of certain complications – diabetes, heart disease, etc.

As someone who works in heart surgery, I can see this issue from both sides.  As many of you know – I am sometimes disheartened by the sheer overwhelming volume of disease (due to diabetes) and the amount of suffering involved for my patients.  I am particularly distressed at times when I see the amount of preventable suffering, and damage my patients experience from not controlling their blood pressure, checking their glucose or taking their medications.  But my patients are already sick – that’s why the are seeing a heart surgeon.  So, I often mourn these lost opportunities to prevent disease (heart attacks, strokes etc.), and I can see how primary care providers, and other providers may feel emotional fatigue and frustration at times.

But, other the other hand –  not every obese person is a stroke or heart attack waiting to happen.  Many of these people can be helped – by education, counseling or even bariatric surgery.  If these people are aggressively followed and cared for, risk reduction can help prevent catastrophic complications – by managing medical conditions that may develop – with aggressive cholesterol control, blood pressure management, etc.

Lastly, medicine is not an exact science – while risks may be greatly increased in many obese people – it is not a guarantee.. Just as it’s a false assumption that all overweight people are sedentary (ie. ‘fat and lazy’), not all overweight people will develop any or all of the complications we’ve discussed before.   But it is guaranteed that these obese patients will suffer, if this trend continues and more and more doctors shun them.

But my door is always open.

By Laura Mortkowitz, Wednesday, November, 16th, 2011
A recent move by Florida ob-gyn physicians to begin turning away overweight patients on the grounds that they were too risky might be the beginning of a new trend. According to Michael Nusbaum, MD, FACS, the health reform bill’s Accountable Care Organizations essentially de-incentivize physicians from taking on morbidly obese patients.
As they stand now, ACOs look at quality measures and they base reimbursements on complications. Doctors already know that a high complication rate will mean less money, and obese patients are considered high-risk patients by definition.
“Under the current bill, the Accountable Care Organizations are looking strictly at outcome measures, so unless that changes I don’t see the perception by physicians changing toward who they’re going to want to treat and who they’re not going to treat,” says Nusbaum, the Medical Director at The Obesity Treatment Centers of New Jersey.
This new practice is not something that would have occurred in the past for two reasons: one, physicians might be reluctant to treat an obese patient, but it was rare to turn them away completely; and two, it was very rare to treat a morbidly obese patient a couple of decades ago.
However, over the last 10 years, the percentage of the population that is overweight has increased dramatically. Today, close to 70% of the population is at least overweight, according to data from the Centers for Disease Control and Prevention. Even more concerning, is the fact that pediatric obesity has tripled over the last 20 years.
“Is the health care system to take care of morbidly obese patients? I would argue that it’s not,” Nusbaum says. “Pretty clearly it’s not. The problem with the health care system is that it lacks infrastructure.”
Most machines and tables can only hold up to 350 pounds, and any patients that exceed that weight might not even be able to get treated at a hospital that doesn’t have the equipment to handle an obese patient. According to Nusbaum, it should be a requirement that hospitals are equipped to treat any morbidly obese patient.
“Nobody is even talking about it,” he says. “Everybody is afraid to even talk about this.”
And it doesn’t seem as if new health laws are encouraging to the treatment of obesity. Under the new health bill’s Essentials Benefit Package, bariatric surgery is not covered because morbid obesity is being considered a poor lifestyle choice. As a result, insurance companies “have become emboldened to say, ‘Well, we’re not going to cover it either,’” Nusbaum says.
In New Jersey, Blue Cross/Blue Shield has 14 insurance policies, and eight of them do not cover bariatric surgery at all.
“What you’re seeing happening is a change in attitude to bariatric surgery and in my opinion a discrimination against those people who have weight issues,” Nusbaum says.
However, there was a rather positive turn of events in Michigan, where bariatric surgery will be covered in 2012 after it was dropped for all of this year.
“They noticed that while they were making money in the short term — they were saving money — they were losing more money by not taking care of these patients,” Nusbaum says. “[The patients] were getting sicker. It was very short sighted.”

//

Read Full Post »

No, researchers aren’t suggesting that entire families undergo bariatric surgery.  But a new study by Woodward, Encarnacion, Peraza, Hernandez – Boussard & Morton (2011) published last month suggests that when one family member underwent bariatric surgery – the rest of the family reaped benefits as well.

As explained in this article by Kristina Fiore at Medpage – there is a family-wide health benefit after bariatric surgery.  After one family member had surgery, other adult members in the family tended to modify their eating habits as well, and subsequently lost weight.  While this study was small, with just 35 families – it shows the huge impact that sociological factors (such as family dietary practices/ habits) have on obesity and health.

Read Full Post »

The American Journal of Cardiology just published a new meta-analysis (a study looking at a collection of other studies) that evaluates the effectiveness of bariatric surgery for cardiovascular risk reduction.  As we’ve discussed before, meta-analyses are often used to sort through large numbers of studies to look for trends and weed out aberrant results or poorly designed studies.  (This is particularly helpful when a poorly designed study gives conflicting results in comparison to the rest of the existing studies.) So, we are going to talk a bit more about the meta-analysis.

In this case, the authors started with 637 studies to evaluate, but ended up using the data from only 52 studies involving almost 17,000 patients.  The first step of a meta-analysis is to find every single study even remotely related to your topic. So the authors pulled out, printed and looked at every single study they could find talking about bariatric surgery.

Then the authors start eliminating studies that aren’t relevant to their topic because once you take a closer look; a lot of the studies initially gathered aren’t really related to your topic at all.  (For example: If the authors gathered all studies talking about Bariatric surgery outcomes – on closer examination – a study about the rate of depression in bariatric surgery patients wouldn’t have any information usable to evaluate cardiac risk in these patients.)  Otherwise it would be like comparing apples to oranges.

Once authors have narrowed the pool to studies that are only looking at relevant topics, with measurable results – the authors then examine the studies themselves.  The authors evaluate all aspects of the studies: what is the study design, what does it measure, (is it designed to measure what it is supposed to measure?), what are the results?  (were the results calculated correctly?)  what are the conclusions?  what are the limitations of the study?

Then the authors summarize all of the findings, and draw conclusions based on the results. (if 50 studies involving 16,900 people show one thing – and 2 studies involving 100 people show something completely different – the authors will discuss that.)

The strengths of meta-analyses are that they summarize all of the existing studies out there – and provide readers with fairly powerful results because they involve large numbers of people.

For researchers, meta-analyses are cheap – particularly in comparison to designing, conducting a large-scale study with hundreds or thousands of subjects.  A meta-analysis doesn’t require federal grants or institutional permissions.  It just requires a computer and journal access (along with a good knowledge of study design, statistics).

As you can imagine, the downside of meta-analyses is that they don’t generate NEW knowledge, since they are summaries of other studies.  Meta-analyses are also limited by the AMOUNT of data already published.  If few researchers have written about a topic, then a meta-analysis isn’t very effective or powerful.  (A meta-analysis on three studies involving only 25 total patients, for example).

Now that we’ve discussed the purpose and function of the meta-analysis, let’s discuss the results of Heneghan’s reported results.

Now, readers need to be very careful when reading blogs, and other articles like mine reporting results such as this – because this is filtered, third-hand information by the time it’s published on blogs, or newspaper articles.  (First source is the meta-analysis itself – which as we’ve discussed is actually a summary evaluation of other work).  Secondary is the Medscape article which summarizes and discusses the results of Heneghan’s study.

Now, that means that anything you read here is essentially third-hand information – if it’s based on the Medscape article.  That’s why we provide links to our sources here at Cartagena Surgery – so readers can read it all first-hand.  This is important because just like the children’s game of telephone, as information is passed from source to source, it is edited, filtered and subtly changed (for reasons of space, editorial preference etc.)

heneghan’s meta-analysis results showed significant reductions in weight, blood pressure, cholesterol and hemoglobinA1c (blood glucose levels) after bariatric surgery.  The Framingham risk score (a score developed based on the landmark Framingham study) which predicts the risk of cardiovascular events (heart attacks, strokes) also showed a significant reduction (which would be expected if all the risk factors such as hypertension were improved).

Framingham Risk Score Calculator

Now, a lot of readers might say, “Wait a minute – isn’t this self-evident?  If you lose weight – shouldn’t all of these things (glucose, blood pressure, cholesterol) improve?”

Yes .- logical reasoning suggests that they should – but in medicine we require hard data, in addition to logical reasoning (ie. A should lead to B versus a study with ten thouand patients proving A does lead to B.)

We need to be particularly careful when suggesting or assuming causality from treatments (surgery) for conditions.  A good example of this is liposuction.  Since liposuction involves the removal of subcutaneous fat – and may result a (a small amount) of weight loss – many consumers assumed that this limited weight loss conferred additional health benefits associated with traditional weight loss.  Wrong!

Sucking fat out of your behind (liposuction) will not lower your blood pressure, cholesterol, or blood pressure and does not replace the health benefits of weight loss or exercise.  I can hear readers snickering now – but that’s because of my phrasing.  For years – many people, some health care providers themselves thought that weight loss, any weight loss lead to the above mentioned health benefits, and that included liposuction related weight loss.  It took several studies to disprove this.  So, in medicine – nothing is obvious – until we prove it is obvious!  (Remember: much of what was “obvious” in 1950’s medicine – is now considered absurd.)

Original Research Article Citation:

Heneghan HD, et al “Effect of bariatric surgery on cardiovascular risk profile” Am J Cardiol 2011; DOI:10.1016/j.amjcard.2011.06.076.  (abstract only – article for purchase).

Medpage Summary Article:

Bankhead, C. (2011). Medical News: Bariatric Surgery gets high marks for CVD risk reduction. Medpage Today.

Read Full Post »

« Newer Posts - Older Posts »