Extra pounds, especially in the belly, are considered a risk factor for urinary incontinence. And some studies have found that when overweight women drop even a modest amount of weight, they can curb their risk of incontinence.

Type 2 diabetes, which often goes hand-in-hand with obesity, is also a risk factor for urine leakage, regardless of weight. So weight loss could be especially helpful for heavy women with diabetes -- but studies hadn't looked at the question until now.

In the new study, researchers found that overweight diabetic women who took up diet and exercise changes lost an average of 17 pounds over a year. And with the weight loss came a lower risk of developing incontinence.

Over a year, 10.5 percent of women in the diet-and-exercise group developed new problems with urine leakage. That compared with 14 percent of women who had not made lifestyle changes.

"Overweight and obese women with type 2 diabetes should consider weight loss as a way to reduce their risk of developing urinary incontinence," lead researcher Suzanne Phelan, of California Polytechnic State University, told Reuters Health by email.

And of course, she added, there are already known benefits of shedding those extra pounds -- like better diabetes control and a lower risk of heart disease.

The findings, reported in the Journal of Urology, are based on 2,739 middle-aged and older women who were part of a larger diabetes study.

At the outset, the women were randomly assigned to one of two groups. In one group, the women were encouraged to cut calories and exercise for three hours a week. The other group had three diabetes education sessions.

Overall, women in the lifestyle group had a lower rate of urinary incontinence over the next year. And it didn't take a lot of weight loss to start to make a difference, Phelan's team found.

For every two pounds a woman lost, the odds of developing incontinence dipped by three percent.

On the other hand, weight loss did not seem to help women who already had urine leakage problems at the study's start.

"We aren't sure why weight loss appeared to impact prevention but not resolution of urinary incontinence," Phelan said.

It's possible, she said, that weight loss is more effective at preventing, rather than treating, urine leakage. Or there may simply have been too few women with existing urinary incontinence to detect an effect of weight loss, Phelan added.

It's also unclear how to account for the drop in incontinence risk -- it might be related to the exercise or the blood sugar reduction, for instance.

Urinary incontinence is very common among women -- in large part because vaginal childbirth is a major risk factor.

One recent study of U.S. adults found that about 53 percent of women older than 20 said they'd had problems with urine leakage in the past year. That was up from less than half of women surveyed several years earlier.

Researchers said the increase was partly explained by rising rates of diabetes and obesity.

SOURCE: bit.ly/zqDrRV Journal of Urology, online January 19, 2012.

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