RNY+VSG Combination?
Anyone who believes restriction has anything to do with long term weight loss and/or diabetes remission need only look at the utter inefficacy of the lap band procedure. That leaves metabolic effects (changes in energy expenditure), hormonal, and malabsorption as potential players in bariatric surgery results.
A number of studies have compared weight loss for proximal (short) vs distal (long) limb length with gastric bypass. All to my knowledge have concluded that proximal RNY has identical short and long term weight loss results as the distal procedure, despite that fact that proximal RNY has almost no caloric malabsorption (6% fat, less than 1% protein, 0% carb), whereas distal RNY imparts significantly more malabsorption. Proximal RNY is also just as effective as distal RNY wrt diabetes remission (both moderately effective). A 2009 Harvard study (the Bible of RNY studies) determined that an enormous increase in energy expenditure -- solely after eating -- is the big-hitter reason for weight loss with RNY, an effect that interestingly does not diminish over time.
VSG also has no malabsorption, but does impart significant weight loss combined with mild-to-moderate diabetes improvement. Though VSG's long-term efficacy lags behind RNY's wrt to both weight loss and diabetes, the results must still be taken seriously. What is interesting to me about VSG is that its mechanism is neither restrictive nor malabsorptive nor metabolic. (The same 2009 Harvard study found the VSG procedure did not produce any of the dramatic post-prandial metabolic effect in energy expenditure seen with RNY.) That leaves only hormonal effects to account for VSG efficacy, and the anatomy of the procedure suggests RNY cannot produce the same hormonal effects as VSG.
That brings us to DS, which by contrast, does impart significant malabsorption, particularly with fats (approaching 80%). I would argue that DS may be accurately thought of as RNY+VSG+fat malabsorption. DS has the best long term weight loss and close to 100% diabetes remission (aka 'cure'). But does the fat malabsorption of DS solely or even mostly account for its improvement over RNY?
Very few, if any studies, have looked directly at malabsorption vs weight loss with DS. The only one I know of found a small advantage of decreased common channel length (CCL) with DS in terms of weight loss. But one thing is clear, based on the studies I've seen -- no matter what common channel length you get with DS, your diabetes will certainly be cured and your long term weight loss will most likely be excellent.
And that brings me (at long last) to my question. Is it possible that combining RNY with DS -- that is, doing a partial gastrectomy of the remnant stomach with RNY -- would achieve results close to those achieved with DS in terms of both long term weight loss and diabetes remission? Is DS (effectively) mostly just RNY+VSG, with the fat malabsorption acting only as a little icing on the cake?
I don't know of any study that has looked at this -- has anyone seen research on such a combination? Some might argue, most people should just get the DS surgery, who cares why it works so well! But compared with RNY and VSG, few doctors are skilled with DS, and DS requires tremendous skill and experience. There aren't large DS "mills" as there are with RNY, and far from disparaging these mills, I would recommend the high quality ones to anyone seeking bariatric surgery (ie, get a surgeon who has done thousands of the procedures). DS is far more dangerous than RNY or VSG, and has more complications. So a simpler procedure that spanned the performance gap between RNY and DS would offer a lot of advantages.
Unfortunately, most surgeons still cling to the ridiculous restriction theory to account for weight loss results, so it would make no sense to them that removing the Ghrelin producing portion of the RNY remnant stomach could possibly effect weight loss.
Another neat thing about such a combination RNY+VSG procedure is that the patient probably wouldn't notice the difference post-op vs standard RNY. The VSG remnant would still produce digestive juices. And the recovery wouldn't be noticably worse than RNY.
My own guess is that such a combination procedure would at least halve the gap in efficacy between RNY and DS, both in term of weight loss and diabetes remission. Since the studies to date suggest that weight regain after RNY correlates with the return of diabetes (and not with an expanded pouch as commonly assumed), such an improvement would be music to the ears of those RNY patients who have struggled with regain.
I know of bunch of people have had VSG that then went on the get RNY (so these people got exactly what I'm describing), but I don't know of any study that has compared their results to those who just got RNY at the start.
Even though I ended up getting RNY, I was always struck by how DS patients were the most informed and intelligent group, so I'd love to hear any thoughts...
The switch only has been done in Europe for decades to cure DM2. They do the whole DS if the patient is obese but the switch only on patients close to a normal weight. My H's BMI was 27 when he had the switch only to cure his diabetes. The only paper I've ever found written about this was by a doc named Noyes. It's still out there. It's the switch that does the magic. And BTW the CC Noyes set as the standard in these cases was 50cm. Very short/high malabsorbtion.
One theory about the cause of DM2 is increased production of intestinal hormones. Hormone production is stimulated by food passing through the small bowel. It makes perfect sense that if the small bowel is bypassed surgically, hormone production drops dramatically. Therefore DM2 gone, like magic. No diet, weight loss, or exercise required.
Very interesting, thanks. One would then think that the distal RNY would confer some diabetes advantage over proximal RNY, yet it doesn't. Perhaps the intestinal bypass has to be extremely long to see any additional advantage over proximal RNY. My thought was that a partial gastrectomy (VSG) of the RNY remnant might produce a significant additive benefit over the standard RNY, getting much closer to DS efficacy re weight loss and diabetes. I would love to see a study that explored weight loss & diabetes resolution across the entire range of intestinal bypass lengths, from proximal RNY with VSG added to remnant stomach so apples-apples re Ghrelin reduction, all the way to CC 50cm DS. In this way, it could be determined once-and-for-all what exactly makes DS superior to RNY. I am not a fan of animal studies, but perhaps that is the only way such a study could be done, realistically.
