Studies Say Obesity Surgery Prolongs Lives
The first long-term studies of stomach stapling and other radical obesity treatments show that they not only lead to lasting weight loss but also dramatically cut deaths attributable to diabetes, heart disease and cancer.
The findings of the studies conducted in Sweden and the United States are expected to lead to more such operations, possibly for less-severely obese people as well.
Obesity surgeries have surged in recent years — along with global waistlines. In the United States alone, 177,600 operations were performed last year, according to the American Society for Metabolic & Bariatric Surgery.
"Bariatric surgeries were pioneered in the 1930s, and perfected over the last few decades," Early Show medical correspondent Dr. Emily Senay said. "The bottom line is, you mechanically reduce the size of the stomach, the amount of calories that people can eat and absorb, and they lose weight."
There are a number of different ways in which this is done, one of the most common being gastric bypass surgery. "Surgeons literally separate the top of the stomach from the bottom the stomach," Dr. Senay said. "They also cut off a portion of the intestine. Then they take that intestine, reattach it to the top of the stomach — you literally bypassed a large part of the stomach and intestine. People can't eat as much. They don't absorb as many calories, clearly, and they lose weight."
Other procedures include gastric banding, in which a tight silicone belt is placed around the stomach, through traditional or laparoscopic procedures.
Researchers in the two studies separately found that obese people who underwent such drastic surgery had a 30 to 40 percent lower risk of dying 7-10 years later, compared with those who did not have such operations.
The research, published in Thursday's New England Journal of Medicine, should put to rest uncertainties about the benefits and risks of weight-loss surgery and may cause governments and insurers to rethink who should qualify for the procedure, some doctors said.
"It's going to dispel the notion that bariatric surgery is cosmetic surgery and support the notion that it saves lives," said Dr. Philip Schauer, director of bariatric surgery at the Cleveland Clinic in Ohio, who had no role in the research.
The Swedish study is the longest look yet at how obesity surgery affects mortality.
Researchers led by Dr. Lars Sjostrom of Goteborg University compared 4,047 people with a body-mass index over 34 who had one of three types of surgery or received standard diet advice. BMI is a standard measure of height and weight and a BMI over 30 is considered obese.
After a decade, those in the surgery group lost 14 percent to 25 percent of their original weight compared to 2 percent in the other group. Of the 2,010 surgery patients, 101 died. There were 129 deaths in the comparison group of 2,037 people.
In the U.S. study, Ted Adams of the University of Utah led a team that looked at 7,925 severely obese people in the state who had gastric bypass. They were matched with similar people who did not have the operation and who were selected through their driver's license records listing height and weight.
After an average of seven years' follow-up, 213 people who had surgery died compared to 321 who did not have the procedure. The study did not look at weight loss.
Deaths from diabetes in the surgery group were dramatically cut by 92 percent; from heart disease by 56 percent; and from cancer by 60 percent.
"We're no really sure why that is the case" with a reduction in cancer, Dr. Senay said. "Is it that people are getting screened once they lose weight? Is there something about losing weight that reduces your cancer risk? These are things I'm sure are going to be explored in future studies."
Surprisingly, the surgery group had a higher risk of death from accidents, suicides and other causes not related to disease. The researchers were puzzled by this.
Both studies were done before surgery advances that have led to smaller incisions and faster recovery time. Experts say future long-term survival rates from obesity surgery should be even better.
While neither study was the gold standard test, where patients are randomly given one treatment or another, surgery's dramatic benefits make it ethically hard to deny patients the operation, said Dr. George Bray of the Pennington Biomedical Research Center at Louisiana State University.
More than 400 million people worldwide are obese and surgery is the only proven method to shed significant pounds in a short time. In the United States, it costs $17,000 to $35,000, and insurance coverage varies.
Weight-loss surgery is considered relatively safe with the risk of death from the surgery at less than 1 percent. Common complications include nutritional deficiency, gallstones and hernia.
U.S. guidelines recommend that surgery be considered only after traditional ways to slim down have failed. Candidates must be at least 100 pounds overweight and have a BMI over 40, or a BMI over 35 plus an obesity-related medical condition such as diabetes or high blood pressure.
This fall, a panel of experts from the National Institutes of Health will revisit the obesity surgery guidelines. It is not yet known whether a BMI change would be considered, said spokeswoman Susan Dambrauskas.
Susan Pisano, a spokeswoman for America's Health Insurance Plans, which represents 1,300 insurers, said the group will rely on any new recommendations from the federal government.
The Sweden study was paid for by the government-funded Swedish Medical Research Council, drug makers Hoffmann-La Roche Inc. and AstraZeneca PLC and Cederroth, which makes health care products. The U.S. study was supported by an NIH branch; one of the researchers has received a lecture fee from a company that makes equipment for obesity surgery.