Body Composition Affects Risk of Urinary Incontinence

A new study suggests that stress and urgency urinary incontinence is twice as prevalent in older women with a high body mass index (BMI).

Researchers at the University of California, San Francisco (UCSF; USA), VU University Medical Center (Amsterdam, The Netherlands), and other institutions conducted a study in 1,475 women (initially aged 70-79) in order to evaluate prospective relationships between body composition and muscle strength with predominantly stress urinary incontinence (SUI) and urgency urinary incontinence (UUI).

Urinary incontinence was assessed using structured questionnaires. Body mass index (BMI), grip strength, quadriceps torque, and walking speed were assessed using physical examination and performance testing. Appendicular lean body mass (ALM) and whole-body fat mass were measured using dual-energy X-ray absorptiometry. At baseline, 14% of the women reported at least monthly predominantly SUI, and 16% at least monthly predominantly UUI. At three years, 14% had new or persistent SUI, and 28% had new or persistent UUI.

The results showed that women had greater odds of new or persistent SUI if they demonstrated a 5% or greater decrease in grip strength, and lower odds of new or persistent SUI if they demonstrated a 5% or greater decrease in BMI, a 5% or greater increase in ALM corrected for BMI, or a 5% or greater decrease in fat mass. Only a 5% or greater increase in walking speed was associated with new or persistent UUI over three years. The study was published in the November 2016 issue of the Journal of the American Geriatrics Society.

“The findings suggest that higher BMI and fat mass are important markers of risk for SUI and UII in older women, and that their risk of SUI may be partially reversible through weight loss,” said lead author Anne Suskind, MD, MSc, of UCSF. “Changes in body composition and grip strength were associated with changes in SUI, but not in UUI, frequency over time. These findings suggest that optimization of body composition may help to modify the risk of SUI, but not necessarily UUI.”

SUI is the loss of bladder control or involuntary loss of urine when coughing, laughing, sneezing, getting up from a chair, or during heavy lifting. It is the most common type of incontinence suffered by women, especially older women. Causes include weak pelvic muscles or a weak sphincter muscle, and giving birth. Chronic coughing, smoking, and obesity may also lead to SUI.

Related Links:
University of California, San Francisco
VU University Medical Center