THURSDAY, Jan. 13 (HealthDay News) -- In an encouraging sign for severely obese women who suffer from incontinence, a new Australian study says that many gain control over urination after undergoing gastric-band weight-loss surgery.

"This could be an additional benefit for females undergoing the procedure," said Dr. Weranja K.B. Ranasinghe, the study's lead author.

"A number of large studies have showed the link between obesity and urinary incontinence, especially in females," Ranasinghe said. "Gastric banding surgery is being used more commonly as an option for weight loss in the obese population, with good effect. But very little is known about the urological issues following gastric banding, so we attempted to investigate this."

In laparoscopic gastric banding, one of the most common forms of weight-loss surgery, surgeons place a band around the top of the stomach, creating a small pouch, which reduces the amount of food people can eat before feeling full.

Obesity is a growing health issue worldwide, increasing the risk for heart disease, high blood pressure, diabetes and cancer. More than half of the people in Australia are overweight or obese, said Ranasinghe, who works in the urology department at Austin Hospital in Melbourne. Also, about one in four people has some form of urinary incontinence, which may be attributable to obesity.

For the study, published in the January issue of the British Journal of Urology International, the researchers analyzed surveys completed by 142 women (average age, 48) and 34 men (average age, 53) who underwent gastric band surgery over a decade at a clinic in Australia. The participants were asked to recall their urinary and erectile dysfunction symptoms before and after surgery.

Sixty-five percent of the women said they had incontinence before to the surgery, as did about a quarter of the men.

The high numbers suggest, but don't prove, that obesity may play a role. "In females, it is thought that the excess weight around the abdominal region increases the pressure on the bladder, causing urinary incontinence, especially when coughing, laughing or sneezing," Ranasinghe said. "In males, this is a more complex mechanism and is poorly understood."

On average, men and women lost about 50 pounds after gastric banding, the researchers found.

Overall, incontinence improved after surgery among the women, but they suffered from more "urge incontinence" -- urination that usually occurs after a sudden urge to urinate. The overall improvement may have occurred because weight loss reduces pressure on the urinary tract, Ranasinghe said.

Symptoms of incontinence in men did not improve after surgery, the study found.

And though 83 percent of the men reported erectile dysfunction before the procedure, overall they said they had more sexual problems afterward.

Ranasinghe said the study numbers for men were small, making it hard to determine if weight loss actually worsened sexual functioning. Also, improvement may take time. The long-term benefits of weight loss, including improvement in blood vessels, are thought to reduce erectile dysfunction, Ranasinghe said.

The study did not analyze sexual sensitivity in the women.

Dr. Natan Bar-Chama, director of male reproductive medicine and surgery at Mount Sinai School of Medicine in New York City, said the study's value is limited because it relies on people's recollections.

However, the findings regarding women and incontinence are consistent with other research, he said.

As for men, it's known that weight loss helps improve erectile dysfunction, he said, although the specific effects of weight-loss surgery still need to be studied.

More information

The American Academy of Family Physicians has more about urinary incontinence.