Overweight women with diabetes may be able to cut their risk of urine leakage if they shed some pounds, a new study suggests.

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 incontinence, regardless of weight. So weight loss could be especially helpful for heavy women with diabetes, however 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% of women in the diet-and-exercise group developed new problems with urine leakage. That compared with 14% 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," said lead researcher Suzanne Phelan, of California Polytechnic State University.

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.

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 – mainly because vaginal childbirth is a major risk factor.

One recent study of U.S. adults found that about 53% of women older over 20 yrs old said they'd had problems with urine leakage in the past year. That was up from less than 50%  of women surveyed several years earlier. Researchers commented that the increase was partly explained by rising rates of diabetes and obesity.

SOURCE: Journal of Urology, online January 19, 2012.