HOLLYWOOD, FLA. — Obese women planning incontinence surgery have more severe urinary incontinence symptom distress, worse quality of life, and more frequent incontinence episodes than overweight or normal-weight women, even after other obesity-related factors are controlled for, according to a secondary analysis of two large study populations.
There are limited data in the literature, however, to explain why obese women with stress urinary incontinence might experience more distress. One possibility is that increased intra-abdominal pressure in obese patients may cause chronic “stress” to the urinary bladder, leading to incontinence, Dr. Holly E. Richter said.
To find out more, Dr. Richter and her associates performed a secondary analysis of women with stress urinary incontinence seeking surgery. They assessed 655 participants from the Stress Incontinence Surgical Treatment Efficacy Trial (SISTEr) (Urology 2005;66:1213-7) and 597 patients from the ongoing Trial of Mid-Urethral Slings (TOMUS)
For the current study, the researchers pooled and grouped the women according to body mass index cutoffs for obesity (30 kg/m
The Urogenital Distress Inventory (UDI) total score, incontinence episode frequency on 3-day diaries, pad weights, and Valsalva leak point pressures were higher among obese women versus overweight and normal-weight women, Dr. Richter said at the annual meeting of the American Urogynecologic Society.
Specifically, the mean UDI total score was 139 in the normal-weight women, 147 in overweight women, and 160 among obese women in SISTEr. In TOMUS, the UDI total scores were 124 in the normal-weight participants, 130 in the overweight participants, and 144 among the obese participants. The differences were statistically significant between groups in both trials.
“Obese women appear to have better urethral function,” Dr. Richter said, based on their higher Valsalva leak point pressures and maximal urethral closure pressures (measured in the TOMUS study). These higher pressures might indicate a compensatory mechanism in obese women.
Other incontinence severity measures, including the UDI urge subscale score and the Incontinence Impact Questionnaire total score also were higher for obese versus other participants, said Dr. Richter, professor of obstetrics and gynecology at the University of Alabama at Birmingham.
Approximately 45% of subjects were obese in both trials. The mean age was about 52 years, the majority of women were white (75%–80%), and there was no significant difference between BMI categories in terms of diabetes incidence, Dr. Richter said.
“Obesity did not [have an] impact in terms of success of surgery, at least in the SISTEr trial,” she said.
Disclosures: The National Institute of Diabetes and Digestive and Kidney Diseases and the National Institute of Child Health and Human Development provided funding. Dr. Richter said she had no relevant disclosures.