Few complications found in weight-loss surgeries

* Study may reassure doctors, patients

* Highest complication rates involved open surgery

* Gastric banding had fewest complications

By Gene Emery

BOSTON, July 29 (Reuters) - A comparison of three popular weight-loss surgeries found them overall to be "safe," addressing earlier concerns, U.S. researchers said on Wednesday.

Some doctors have been reluctant to recommend weight-loss surgery to obese patients because of the safety concerns.

"The surgery is safe," said Dr. Bruce Wolfe of Oregon Health & Science University, who helped lead the study published in the New England Journal of Medicine.

"It should give more patients and their primary care providers confidence to look at surgery," Wolfe said in a telephone interview.

In the study of three types of stomach reduction surgeries, one out of 333 patients died 30 days after the surgery, and one in 24 had serious complications.

But the study also found the likelihood of dying from one type of open surgery could be as high as 1 in 47, largely because of the risk factors of the patients who receive it.

"It's not perfect," he said. "But with these current data, the safety we've achieved is definitely an improvement over the past."

Weight-loss or bariatric surgery is becoming increasingly popular as obese people struggle to lose weight and avoid the health complications that accompany the extra pounds -- such as diabetes, heart disease, joint pain and some cancers.

Well over 171,000 such operations are done in the United States each year. The National Institutes of Health recommend the surgery for someone with a body mass index of at least 40.

BMI is equal to weight in kilograms divided by height in meters squared. A person 5 feet 5 inches tall (165 cm) with a BMI of 40 would weigh more than 240 pounds (109 kg).

The study tracked 1,198 severely obese people who underwent gastric banding, where an adjustable band is inserted in a small incision and wrapped around the top of the stomach, giving the patient the illusion of fullness with small meals.

The rest were treated with a form of gastric bypass surgery known as Roux-en-Y, in which the stomach is closed off near the top, creating a small pouch. The surgery was done laparoscopically -- through small incisions in the belly -- in 2,975 people. In 437, the gut was opened up.

Nobody died within 30 days of the banding technique and the rate was 0.2 percent -- 1 in 500 -- with laparoscopic bypass. The death rate was 10 times higher with so-called open bypass.

The overall likelihood of major complications, including death, blood clots or the need for follow-up surgery, showed a similar pattern. It was 1 percent for banding, 4.8 percent for laparoscopic bypass and 7.8 percent for open bypass.

Wolfe said the pattern is not surprising because surgeons will not try laparoscopic bypass on patients with many risk factors. When they adjusted for risk factors, the chance of major complications was much more comparable between both types of Roux-en-Y bypass.

Both Johnson & Johnson (JNJ.N) and Allergan Inc (AGN.N) make bands for weight-loss surgery.

Dr. Malcolm Robinson of Harvard Medical School said in a commentary the complication rates "are similar to those seen in other major operations" but since the study involved 33 U.S. surgeons certified as highly skilled, the results "may not be widely reproducible." (Editing by Eric Walsh)