Prevalence of Urinary Incontinence in the United States 2015-2020

Objectives: To describe updated weighted prevalence estimates of symptomatic urinary incontinence (UI) in the United States. Secondary objectives were to describe the prevalence of UI sub-types and compare current prevalence to estimates from 10 years prior.

Methods: This was a cross-sectional analysis including non-pregnant, female, age >/= 20 years-old participants in the 2015-3/2020 National Health and Nutrition Examination Survey (NHANES) database, which is designed to be representative of the non-institutionalized, civilian, United States population. The primary outcome was self-reported UI, defined as a score of >/=3 on the incontinence severity index (range 0-12). Self-reported UI sub-types (stress, urgency, mixed, other) were also compared. Stress UI was defined as leakage of urine exclusively “with an activity like coughing, lifting or exercise”. Urgency UI was defined as leakage of urine exclusively “with an urge or pressure to urinate and [you] couldn't get to the toilet fast enough”. Mixed UI was defined as endorsing both stress UI and urgency UI. Other UI was defined as endorsing leakage of urine “without an activity like coughing, lifting, or exercise, or an urge to urinate”. Available covariates including age, body mass index (BMI), comorbidity count, education, parity, and poverty-income ratio were examined for association with UI. Descriptive statistics and multivariable logistic regression models with odds ratios and 95% confidence intervals were reported. Current estimates were compared to the prior estimate of 17.1%, based on NHANES data from 10 years ago (Wu et al) with a Z test.

Results: A total of 6,446 participants met inclusion criteria and had UI data. There were differences in age, race/ethnicity, and education between those with and without UI data (p < 0.05). The weighted prevalence of any UI was 22.3% (95%CI 20.8-23.8). Of those with UI, the greatest proportion of participants had mixed UI (697/1497, 46.6%), followed by stress UI (242/1497, 16.2%), then urgency UI (142/1497, 9.5%, Table 1). Twenty-seven participants (27/1497, 1.8%) endorsed other UI alone, while 26% (389/1497) endorsed other UI in combination with stress and/or urgency UI. On multivariable logistic regression adjusted for age, BMI, comorbidities, parity, prior hysterectomy and race/ethnicity, BMI >/=30 (OR 2.74, 95%CI 2.07-3.63), >/=3 comorbid diseases (OR 2.12, 95%CI 1.54-2.93), BMI 25.0-29.9 (OR 1.78, 95%CI 1.34-2.36), and increasing age (OR 1.04, 95%CI 1.03-1.04) were associated with UI. There were no differences in the prevalence of UI from 2015-2016 compared to 2017-3/2020. Estimates found in the current study are higher than reports based on 2005-2010 NHANES data (Wu et al, p< 0.001).

Conclusions: Approximately one in five women endorse UI, with the most common sub-type being mixed UI. The prevalence of UI appears to have increased in the United States.

Wu JM et al. Prevalence and trends of symptomatic pelvic floor disorders in U.S. women. Obstet Gynecol. 2014 Jan;123(1):141-148.