AUA 2018: Impact of Lifetime Obesity on Urinary Incontinence in the Women’s Health Initiative

San Francisco, CA USA (UroToday.com) Several studies in this session addressed the association of obesity and the metabolic syndrome with urinary incontinence. Obesity is a known risk factor for developing urinary incontinence (UI), and some studies have suggested that obese women have worse outcomes in the treatment of urinary incontinence. Recently there has been an emphasis on research into the prevention of pelvic floor disorders, and obesity prevention may be a target for urinary incontinence prevention. However, this is a difficult field to study as it requires long-term, longitudinal data on weight and urinary incontinence, as well as other patient factors. The Women’s Health Initiative (WHI) data allows for the long-term study of multiple factors affecting women and their health over time. The authors here used the WHI to evaluate the impact of obesity on urinary incontinence over a woman’s lifetime.

The authors used the WHI to identify women aged 50-79 who were enrolled in the study and did not have urinary incontinence or neurological deficits at baseline. The BMI was self-reported at ages 18, 35, and 50 and was used to create a BMI trajectory for each subject. Overweight (BMI > 25) and obesity (BMI > 30) duration in years were calculated per subject. Three years after study entry the participants were asked about their urinary symptoms and the relationship between overweight or obesity duration was correlated with the development of urinary incontinence.

15,240 women met inclusion criteria and were included in the analysis. 30% of the subjects developed urinary incontinence over the three-year period. 12.4% developed stress urinary incontinence (SUI), 14.7% developed urgency urinary incontinence (UUI), and 1.9% developed mixed urinary incontinence (MUI). Women with no history of being overweight or obese (44.5%) were used as a reference group. The duration of overweight and obesity was associated with the development of UUI, SUI, and UI. Higher duration of overweight and obesity was associated with increased severity of UI, with more frequent episodes of UI in these women. Women with a higher duration of overweight and obesity had higher limitation in activity due to UI. In addition, women who gained weight were more likely to have worsening of UI, while those who lost weight showed no difference in rates of UI.

While the risk of UI with obesity is established, the nature of this association is not well defined. While these results cannot be interpreted to assume that obesity is a cause of UI, they certainly demonstrate that there is an association between the two. Additionally, the results show a tendency for more severe incontinence with a greater impact on daily activities when women are obese or overweight for a longer amount of time. Interestingly, they did not demonstrate an association of weight loss with a decreased amount of UI. Future studies may be able to elucidate how obesity prevention efforts can help to prevent the onset of pelvic floor disorders in women.

Presented by: Judy Choi, MD; University of California Irvine

Written by: Dena Moskowitz, MD; Fellow, Female Pelvic Medicine and Reconstructive Surgery, Virginia Mason Medical Center, Twitter: @demoskowitz, at the 2018 AUA Annual Meeting - May 18 - 21, 2018 – San Francisco, CA USA