Great news for the morbidly obese!
http://www.time.com/time/health/article/0,8599,1655367,00.html
Wednesday, Aug. 22, 2007
Gastric Bypass Lowers Risk of Death
By Sora Song
Whether one regards bariatric surgery — last-resort weight-loss operations
such as gastric bypass and stomach stapling — as an essential treatment for
obesity or as a failure of the fat person's will, the fact is, it works.
Studies have shown that after surgery, patients often lose 50% or more of
their excess weight — and keep it off — and symptoms of obesity-related
conditions like diabetes, high blood pressure, high cholesterol and sleep
apnea are improved or eliminated altogether. Now, two new studies in the
New England Journal of Medicine (NEJM) show another long-term benefit: a
lower risk of death.
The larger of the two studies — the largest of its kind — led by
researchers at the University of Utah School of Medicine, looked
specifically at gastric bypass surgery, also known as Roux-en-Y gastric
bypass, which accounts for 80% of all bariatric surgeries in the U.S. The
operation involves creating a small walnut-size pouch at the top of the
stomach, which is then stapled off and connected to the small intestine
lower down than usual; the result is that patients can eat only an ounce of
food at a time, and the food bypasses most of the stomach and the top part
of the intestine, limiting the number of calories the body absorbs.
In the Utah study, researchers compiled data on 15,850 severely obese
people, half of whom had undergone gastric bypass surgery between 1984 and
2002, and half who were from the general population and had had no surgical
intervention for obesity. Overall, researchers found, the surgery patients
were 40% less likely to die from any cause during a mean 7 years of
follow-up, compared with the obese controls. What's more, the mortality
rate attributable to obesity-related disease was 52% lower on the whole in
the surgery group: after gastric bypass, patients were 92% less likely to
die from diabetes, 59% less likely to die from coronary artery disease, and
60% less likely to be killed by cancer.
Results like these have got some doctors intrigued enough to start thinking
about bariatric surgery as a treatment for conditions other than obesity
—especially diabetes. A growing body of research suggests that the surgery
may reverse the disease, a potential solution that could help some 20
million American diabetics. Though the current NEJM study did not
specifically study the impact of bariatric surgery on diabetes, it did
reveal a 92% reduced risk of death from the disease in surgery patients
—findings that support what has been emerging in other experiments. "In
more than 80% of patients who are severely obese and have diabetes and then
have gastric bypass surgery, the diabetes is cured," says Ted Adams,
professor of cardiovascular genetics at the University of Utah School of
Medicine and lead author of the new study. "The interesting thing is that
the resolution of diabetes happens within a few weeks following surgery,
long before patients have lost their weight." Like some other researchers
in the field, Adams believes that the surgery triggers other biological
mechanisms, separate from weight loss — perhaps an interruption of a
crucial biochemical pathway or a change in the release of certain hormones
in the stomach or small intestine — that may have powerful effects on
diabetes.
"The gastric-bypass patient is really providing a source of intriguing
research related to all kinds of disease treatment as well as weight gain
and weight loss," says Adams.
The second study, led by researchers at Gothenburg University in Sweden,
involved 4,047 obese volunteers, 2,010 who underwent some form of bariatric
surgery and 2,037 who received conventional obesity treatment, including
lifestyle intervention, behavior modification or no treatment at all. Ten
years after surgery, researchers report, the bariatric surgery patients had
lost more weight and had a 24% lower risk of death than the comparison
group. Though the overall number of subjects in this study is much smaller
than the first, the results confirm general benefits of bariatric surgery,
and gastric bypass in particular: after 10 years, bypass patients had
maintained a 25% weight loss, compared to a 16% loss in patients who had
stomach stapling, and 14% in those who underwent a banding procedure.
In both studies, surgery patients had an overall lowered risk of death, but
an interesting finding in the Utah study shows that these patients were 58%
more likely to die from other causes, such as suicide and accidents. The
authors speculate that as people lose weight and become more active, they
also become more prone to accidents, which may up their risk of death.
Surgery patients may also have pre-existing psychological problems — a
history of abuse, perhaps — that can't be resolved by losing weight. "There
have been some studies reporting that following bariatric surgery, some
individuals may be more prone to chemical dependency, such as increased
alcohol use," says Adams. "There's some speculation that certain addictive
behaviors that are in place before the surgery — with food, for example —
are transferred to alcohol or another addictive behavior."
"Hopefully this research will stimulate additional evaluation of what the
optimal approach is for evaluating candidates for this surgery," says
Adams. "I think we should never lose track of the importance of individual
evaluation of benefits and risks."
Last year, an estimated 177,600 patients underwent bariatric surgery, a
figure that's likely to grow as Americans get fatter and fatter. Though
modern surgery techniques have become more sophisticated, less invasive and
safer than in the past, the bariatric procedure still carries all the risks
of any other operation. Patients have a .5% to 1% chance of death. The risk
of gallstones goes up. Sometimes a second surgery is necessary. And all
patients must be careful to make up for vitamin and mineral deficiencies.
The surgery isn't for everyone; current guidelines recommend it as a last
resort, only for the morbidly obese who have a BMI of 40 and higher, or for
the obese with a BMI of 35 and higher plus a serious weight-related illness
like diabetes or hypertension.