CHICAGO (AP) — Very obese older men hoping to live longer may be let down by a new long-term study that found weight-loss surgery didn't increase survival for people like them — at least during the first seven years.
Prior studies have found stomach stapling and other
obesity surgeries improved survival rates after two to 10 years. The new study
in mostly older male veterans suggests one of two things: Not everyone gains
equally from surgery, or a survival benefit may show up later in older men,
after more years of follow-up.
Previous findings came mainly from studies of
mostly younger women.
"Nearly all prior studies have found bariatric
surgery to be associated with reduced mortality. But those studies were
conducted on very different patient populations using less rigorous
methods," said lead author Matthew Maciejewski of the Veterans Affairs
Medical Center in Durham, N.C.
The patients' organ damage from obesity could have
been too far along for weight loss surgery to reverse it, some experts said.
"It may be too little too late," said Dr.
Philip Schauer of Cleveland Clinic's Bariatric and Metabolic Institute. He was
not involved in the study. "You may have to intervene earlier for a
survival benefit."
Evidence has been mounting for the health benefits
of obesity surgery, so the new results may surprise some people. U.S. doctors
now perform more than 200,000 obesity surgeries a year at an estimated cost of
$3 billion to $5 billion. Schauer said a definitive study on survival could
cost $200 million.
The new study, released Sunday to coincide with a
medical meeting, will appear in Wednesday's Journal of the American Medical
Association.
Benefits of obesity surgery — improved quality of
life, weight loss and reductions in diabetes symptoms, blood pressure and sleep
apnea — may be reason enough to choose the treatment.
"These results are not an indictment of
surgery," Maciejewski said. He and his colleagues plan to follow the
patients longer to see if a survival benefit shows up 10 to 14 years after
surgery.
The study, while rigorous, wasn't the gold standard
where people are randomly assigned to have one treatment or another. Instead,
researchers compared nearly 850 patients who had surgery in Veterans Affairs
hospitals with other obese veterans. The two groups were as similar as
possible, matched for age, gender, race and marital status.
After nearly seven years, the two groups were
equally likely to be alive.
Without the painstaking matching analysis, the
researchers did see a lower death rate in the surgery group compared to a group
of obese patients who didn't have surgery. But that could mean the patients who
underwent surgery were healthier than the patients who didn't.
All the surgery patients had gastric bypass, a
method that makes the stomach smaller by stapling and allows food to skip much
of the small intestine. The smaller stomach holds less food and the digestive
detour means the body absorbs fewer calories.
The patients had surgery between 2000 and 2006.
Their average age was 49 and their average body mass index was 47. A BMI of 30
or more is considered obese.
In the study, 11 patients died within the first
month after surgery, a rate four times higher than in other studies. That could
be because the surgery is more difficult in men than in women, said study
co-author Dr. Edward Livington of University of Texas Southwestern School of
Medicine.
"Women tend to collect fat in the thighs and
hips rather than in the abdomen," Livingston said. Men's fat accumulates
in the belly, making it trickier for surgeons to get through it to the organs.
Some outside experts were troubled by the
post-surgery death rate. Dr. David Flum of the University of Washington School
of Medicine said, regardless of the cause, the higher death rate after surgery
would make it difficult to demonstrate a survival advantage.
Dr. Bruce Wolfe, president of the American Society
for Metabolic & Bariatric Surgery and a professor of surgery at Oregon
Health & Science University in Portland, said the researchers may see a
survival benefit with more years of follow up.
"This probably won't deter many people who
want surgery," said Wolfe, who wasn't involved in the new study.
"They're sick. They have joint disease. They have trouble breathing.
They're doing it to improve their health and quality of life."
Copyright 2011 The Associated Press.
