Weight loss may restore continence in obese women

April 1, 2009

By losing just 8% of their total body weight, overweight and obese women can significantly reduce the frequency of urinary incontinence episodes, according to results of a multicenter trial.

San Francisco-By losing just 8% of their total body weight, overweight and obese women can significantly reduce the frequency of urinary incontinence episodes, suggesting that weight loss should be offered as a first-line, non-surgical treatment for incontinence, according to results of a multicenter trial.

Clinical trials have shown that behavioral weight loss interventions decrease the risk of developing type 2 diabetes and high blood pressure, improve control of high blood pressure and cholesterol levels, and enhance mood and quality of life. In their previous research in smaller cohorts, Dr. Subak and colleagues observed that weight loss might also lead to improvement in incontinence (Int Urogynecol J Pelvic Floor Dysfunct 2002; 13:40-3 and J Urol 2005; 174:190-5).

"Prior studies looked at severely obese women undergoing bariatric surgery or, in the case of our own work, women on a low-calorie liquid diet. Both interventions are much more aggressive than the intervention we used in this study," said Dr. Subak.

"This weight loss intervention is a generalizable, reduced-calorie diet and exercise program with less weight loss than [was seen in] the earlier trials."

Women in this study were all overweight or obese and ranged in age from 42 to 64 years. Each reported at least 10 urinary incontinence episodes per week. All women were assigned randomly to either an intervention group with group-based diet and exercise and behavioral modification sessions or to a control group.

Guided weight loss more effective

At baseline, body mass index and weekly number of incontinence episodes self-recorded in a 7-day voiding diary were similar for the intervention and control groups.

At 6 months, women in the intervention group had a mean weight loss of about 8% (7.8 kg), while controls lost a mean of 1.6% (1.5 kg) (p<.001). Compared with the control group, the women in the weight loss group had a greater decrease in the frequency of stress incontinence episodes (58% vs. 38%; p=.02), but not in urge incontinence episodes (42% vs. 26%; p=.14).

"Weight is a stronger risk factor for stress incontinence than urge incontinence," Dr. Subak noted. "So we hypothesized that weight loss would have a greater effect on stress than urge incontinence. Also, the mechanisms for stress and urge incontinence are different, so the mechanism of the treatment effect of weight loss may also be different, based on type."

In addition, a higher proportion of women in the weight-loss group than the control group had a "clinically relevant reduction" of at least 70% in the frequency of all incontinence episodes (p<.001), stress incontinence (p=.009), and urge incontinence (p=.04).

Women in the weight loss group compared to the control group also perceived a greater decrease in incontinence frequency, regarded incontinence as less of a problem, and reported higher satisfaction with change in their incontinence.

Dr. Subak said that urologists "should consider engaging primary care providers and other resources" when working with overweight or obese women who are looking to lose weight as a method of improving their continence.