Prevalence of urinary incontinence and pharmacologic treatment among US women from 2003 to 2019

Objectives: Urinary incontinence and overactive bladder (OAB) impact a large number of US women. Unfortunately, these conditions are often underdiagnosed and inadequately treated. Disease recognition is an important first step in providing appropriate care to symptomatic patients. We aimed to characterize trends in the prevalence of these diseases and treatment rates over time.

Methods: Data from the National Health and Nutrition Examination Survey (NHANES, 2001-2018, N=30,478) and the National Ambulatory Medical Care Survey (NAMCS, 2003-2019, N=249,989) were used to identify women with symptomatic incontinence and OAB as well as determine the frequency of prescription use for OAB medications. Logistic regression models were used to calculate least square means estimates of adjusted prevalence (adjusting for race, age, body mass index and insurance status). Joinpoint Regression Program was used to perform weighted least squares regression to obtain adjusted annual percent change (APC). Trends were assessed overall and by race, age, body mass index and insurance status.

Results: In this analysis urinary incontinence and OAB prevalence were high, at 53.7% and 31.2% respectively in the final survey year of NHANES (2017-18). Women aged >65 had the highest prevalence at 73.4% (Table). There was an overall increase in any incontinence [APC 1.14, (0.27, 2.03), p=0.017] and OAB [APC 0.24, (0.64, 1.84), p=0.002] over time. Trends in incontinence varied by age (p-interaction 0.003). Older women demonstrated increased overall incontinence [APC 2.30, (1.03, 3.06), p = 0.004], urgency incontinence [APC 1.43, (0.35, 3.53), p=0.016], and OAB [APC 1.84, (0.73, 2.97, p=0.006] annually. Rates of stress urinary incontinence remained stable over the study period. Overall, only 3.50% of patients with symptoms of OAB reported pharmacologic treatment in NHANES. NAMCS analysis showed that anticholinergic prescription rates increased significantly from 2003 until 2014 (p=0.036) (Figure). Since this time there has been a trend toward decreasing anticholinergic prescriptions (p=0.099) with 2014 as the inflection point (p=0.014). Sub-analyses by race, age or insurance status were not possible for OAB medications given the overall low prevalence of these prescriptions.

Conclusions: These large nationally representative surveys of US women demonstrate an increasing prevalence of urinary incontinence and OAB. Additionally, this study highlights the undertreatment of patients with symptomatic OAB. Since 2014 anticholinergic prescriptions have decreased, possibly related to increased use of alternatives such as beta-agonists, intravesical Botox injections or percutaneous tibial nerve stimulation. In addition, concerns over mental status changes in older populations using anticholinergics may be leading providers and patients to seek different therapies. The high and increasing prevalence coupled with relative under treatment of incontinence and OAB underscore the importance of screening for these conditions. More research is needed to best determine strategies to identify and properly treat patients, especially in the setting of an aging population.