The authors report no financial relationships relevant to this article.
Four recent studies enhance our understanding of the benefits, efficacy, and risks of the following interventions in women who have urinary incontinence (UI):
- weight loss. Women who were randomized to intensive weight loss reduced the total number of UI episodes in a week by 47.4%—compared with 28.1% in the group randomized to a structured educational program.
- midurethral slings. Treatment of stress UI arising from intrinsic sphincter deficiency was more successful in women randomized to tension-free vaginal tape (TVT) than in women assigned to transobturator tape (TOT). In the first group, urodynamically confirmed stress UI was present in 21% of subjects after treatment, compared with 45% in the TOT group.
- botulinum toxin type A (Botox) injection. Women who had refractory urge incontinence were likely to improve significantly after injection of Botox. Sixty percent of women treated with Botox reported a reduction in incontinence after treatment, with a median response of 373 days, compared with 62 days in the placebo group.
- sacral neuromodulation. The mean number of urge incontinence episodes decreased from 9.6 to 3.9, and the mean number of voids per day decreased from 19.3 to 14.8 in a 5-year follow-up study.
Despite the promise of these findings, all of the studies had limitations, and several identified risks associated with the intervention. These limitations and risks are detailed in the articles that follow.
Urinary incontinence is no small problem. It affects more than 13 million women in the United States alone, and costs more than $20 billion annually in direct health-care costs.1
Despite the high prevalence of urinary incontinence, women are often reluctant to discuss symptoms with their physician. As a result, the condition remains undiagnosed or undertreated in many women.2
The most common types of urinary incontinence include:
- stress incontinence – leakage upon effort, exertion, or increased abdominal pressure
- urge incontinence – leakage accompanied by, or immediately preceded by, urgency
- mixed incontinence – leakage with urgency as well as effort, exertion, or increased abdominal pressure.
Another common problem is overactive bladder syndrome, which involves urgency with or without leakage, and usually increased frequency and nocturia as well.3
Although the midurethral sling revolutionized the treatment of stress urinary incontinence, most women who have incontinence experience mixed symptoms, making it a more challenging condition for the general-practice ObGyn to treat successfully. Furthermore, traditional therapies such as behavior modification, pelvic floor exercise, and medication have had only modest success in certain patient populations.
Subak LL, Wing R, Smith West D, et al. Weight loss to treat urinary incontinence in overweight and obese women. N Engl J Med. 2009;360:481–490.
Obesity increases intra-abdominal pressure, thereby exerting added force on the bladder, urethra, and pelvic floor and potentially exacerbating urinary incontinence (UI). It has been hypothesized that weight reduction reduces these forces and improves incontinence.
This randomized, clinical trial of 338 women showed that weight loss does have an effect on UI. Investigators compared an intensive 6-month weight loss program—designed to prompt a weight loss of 7% to 9% of body weight—with a structured educational program. The primary outcome was the percentage of change in the number of UI episodes reported in a 7-day voiding diary at 6 months.
After 6 months and a mean weight loss of 8% of baseline body weight, the women in the intensive weight loss group experienced a mean decrease of 47.4% in the total number of UI episodes in a week. Compare this with a mean weight loss of 1.6% (P<.001) and a mean decrease of 28.1% in UI episodes in the control group (P=.01). The reduction in the total number of UI episodes was primarily attributed to a reduction of 57.6% in stress-induced UI in the intensive weight loss group, compared with a reduction of 32.7% in the control group (P=.02).
Women in the weight loss program also perceived incontinence to be less of a problem and reported greater satisfaction with the change in their incontinence at 6 months than did women in the control group (P<.001).