Band surgery trial reverses type 2 diabetes
Surgery is rarely offered as a treatment for diabetes, but that may soon change, writes Health editor Adam Cresswell
PRISON offier Domenic Mercuri was certainly on the heavy side when his doctor told him he had type 2 diabetes: carrying just over 100kg on a 1.73 metre (5ft 7in) frame put him well into the obese category.
Battling symptoms including dizziness and high blood pressure, he’d realised he wasn’t in top form. But it still came as a shock to hear in early 2004 that his blood glucose level was 20 millimoles per litre (mmol/L) — more than twice the healthy limit.
Drugs prescribed by his GP quickly brought that down to 9mmol/L, the upper end of the healthy range. But Mercuri, now 51, was still feeling out of sorts. So when he saw an advertisement seeking participants for a trial to test the effectiveness of surgery in obese patients with type 2 diabetes, he jumped at it.
The 60 obese patients on the trial, conducted by Monash University’s Centre for Obesity Research and Education, were divided into two groups: one group received usual diabetes care, namely anti-diabetes drugs such as metformin which increases sensitivity to insulin, as well as diet and lifestyle advice.
The other group — into which Mercuri was randomly assigned — received adjustable gastric banding surgery. In this procedure, a band is placed around the top part of the stomach, slowing the rate at which food can pass into the main part of the stomach and causing the patient to feel ‘‘ full’’ much sooner.
The trial recorded some dramatic findings last week after following the patients for over two years. Patients given the gastric band lost an average of 20 per cent of their weight, compared to a 1.4 per cent weight loss in the normal care group. The surgery patients also cut their blood sugar by 80 per cent, compared to 20 per cent of the normal-care patients; and the surgery patients also enjoyed a bigger cut to their blood pressure and use of drugs.
Perhaps most dramatic of all, 22 of the 30 surgery patients (73 per cent) shed their diabetes altogether, compared to just four (13 per cent) of the 30 in the normal-care group — meaning surgery led to a five times greater rate of remission from the disease than conventional treatments.
About 14 months after the trial ended, Mercuri is a changed man. He now weighs just over 70kg instead of 100kg; he is no longer diabetic; he no longer has to take drugs for diabetes or high blood pressure; and he feels more fit and energetic.
‘‘ The pain associated with the surgery is minimal,’’ he says. ‘‘ With what it has done for my health, I would do it again, and I have recommended it to quite a number of people.’’
The study findings, published in the Journal of the American Medical Association (2008;299(3):316-23), have made a considerable splash, particularly in the US which is facing an obesity epidemic even worse than Australia’s.
In an accompanying editorial in the journal, two experts from the University of Washington in Seattle described the findings as ‘‘ clear and striking’’ and together with other recent findings provided ‘‘ insights . . . (that) may be the most profound since the discovery of insulin’’.
As a result, they said doctors and medical Monash University’s Centre for Bariatric organisations ‘‘ should reconsider the role of Surgery, says that while remission of diabetes surgery to treat diabetes’’. ‘‘ It is time for a has been observed previously, the new study major shift in the way the health care — being a randomised controlled trial, community considers diabetes treatment considered the gold standard for medical goals,’’ they wrote in the editorial evidence — is one of the first to provide (2008;299(3):341-3). confirmation that weight loss itself can bring
Bariatric (obesity) surgery covers a number this about. of procedures, of which laparascopic (keyhole) It also shows the scale of the increased adjustible gastric banding surgery is just one. weight loss that surgery can bring about.
While it is still invasive, and does have some ‘‘ The cost of treating someone with risks and side effects, it is generally much diabetes (on existing therapies) is very high — safer, quicker and less painful than some older on average it’s probably in excess of $10,000 forms of gastric surgery, such as stapling and a year,’’ O’Brien says. gastric bypass. ‘‘ The cost of gastric banding surgery in a
Contrary to common belief, gastric banding public hospital is likely to be about $5000 to does not squash the stomach into a smaller $8000 in total. What you are buying for that volume. Instead, a hollow band is placed cost is a major likelihood of the disease going around the top part of the stomach, which can into remission . . . This (surgery) sounds to be be inflated to the desired tension by infusing a pretty good therapeutic pathway.’’ saline or other solution. However, surgery is not being presented as
It creates a pocket at the top of the stomach, a treatment for everyone with diabetes. which fills quickly as food is eaten, and slows O’Brien stresses that the beneficial effects the rate at which this food can progress into were recorded in obese (not just overweight) the main part of the stomach. patients with type 2 diabetes, all of whom
While it used to be thought that a feeling of entered the trial with a body mass index of ‘‘ fullness’’ was triggered by the release of between 30 and 40 — well above the healthy hormones after a meal, it is now thought this upper limit of 25. may be triggered by nerve signals — and that They were also all at relatively early stages the gastric banding sends these signals to the of the disease, and none needed to take brain, even though the stomach contains little insulin. or no food. ‘‘ If we see someone at 10 years with this
‘‘ You can go through a day without feeling disease, and they are on insulin, the likelihood hungry,’’ says Mercuri, who says he would is we are not going to put them into take 30 minutes to eat an entree-sized meal. remission,’’ O’Brien says. ‘‘ In this study we
Co-author professor Paul O’Brien, head of only accepted people who had been diagnosed for two years. It’s a strong message to the doctors who treat diabetics: they don’t only have to think about surgery, but think about surgery early in that person’s disease.’’
Although follow-up in the study was limited to two years, evidence from previous research shows remission from diabetes can be maintained beyond 10 years, he says.
The study’s findings raise the question of whether there should be a much wider use of surgery in obese patients who also have type 2 diabetes than currently happens.
While there are currently about 8000 gastric banding operations a year in Australia — a figure O’Brien says is ‘‘ increasing all the time’’ — this is a tiny figure in population terms.
Surgery has traditionally not been considered as a treatment for diabetes. It is not generally funded through public hospitals.
Melbourne’s Austin Health is one that does allow gastric banding — but the numbers are limited to just 12 patients per year.
Professor Joe Proietto, an Austin endocrinologist and professor of medicine at the University of Melbourne, says even then patients can only qualify if they have failed on other therapies.
A co-author of the study, Proietto says that while there has been a strong preference for non-surgical therapies for obesity, the shortterm success of these treatments tended to fade over the longer term.
Contrary to old-fashioned stereotypes that obese people lack willpower, Proietto says there are ‘‘ good biological reasons’’ why people find it hard to reduce their weight and then keep their new, lower weight.
This is because the body employs a number of tricks in an attempt to regain what it thinks is the ‘‘ right’’ weight. The metabolic rate drops; the levels of leptin, a hormone that helps regulate food intake, also falls by about half. Levels of another hormone, ghrelin, which stimulates food intake, rise.
The gastric band, which makes the brain think the stomach is full, short-circuits these defensive systems and allows people to cut their food intake much more easily.
‘‘ These physiological adaptations explain the perplexing and mysterious data about why people can’t keep weight off,’’ Proietto says.
‘‘ It also shows it’s going to be terribly difficult to control obesity with public health measures. There haven’t been any public health measures that have shown any impact (on obesity), up to now.’’
Like Proietto — who says gastric banding appears to be ‘‘ very cost-effective’’ — O’Brien rejects the idea that obesity is the result of people showing insufficient willpower over their lifestyle.
‘‘ These people are desperately keen to lose weight, and try harder than most people,’’ he says. ‘‘ But they have a set point to their weight that’s too high. Generally they can give more than a 20-year history (of weight loss attempts).
‘‘ Rather than blame them, we should face up to the fact that as a community, if we can help people, we should help them. There are so many people who have this problem who could be helped.’’
Band aid: Professor Paul O’Brien says surgery can bring about weight loss and put type 2 diabetes into remission