Epidemiology of mixed, stress, and urgency urinary incontinence in middle-aged/older women: the importance of incontinence history

Abstract

Introduction and hypothesis: Urinary incontinence (UI) is common and the relationship among its subtypes complex. Our objective was to describe the natural history and predictors of the incontinence subtypes stress, urgency, and mixed, in middle-aged and older US women. We tested our hypothesis that UI subtype history predicted future occurrence, evaluating subtype incidence/remission over multiple time points in a stable cohort of women.

Methods: We analyzed longitudinal urinary incontinence data in 10,572 community-dwelling women aged ≥50 in the 2004-2010 Health and Retirement Study. Mixed, stress, and urgency incontinence prevalence (2004, 2006, 2008, 2010) and 2-year cumulative incidence and remissions (2004-2006, 2006-2008, 2008-2010) were estimated. Patient characteristics and incontinence subtype status 2004-2008 were entered into a multivariable, transition model to determine predictors for incontinence subtype occurrence in 2010.

Results: The prevalence of each subtype in this population (median age 63-66) was 2.6-8.9 %. Subtype incidence equaled 2.1-3.5 % and remissions for each varied between 22.3 and 48.7 %. Incontinence subtype incidence predictors included ethnicity/race, age, body mass index, and functional limitations. Compared with white women, black women had decreased odds of incident stress incontinence and Hispanic women had increased odds of stress incontinence remission. The age range 80-90 and severe obesity predicted incident mixed incontinence. Functional limitations predicted mixed and urgency incontinence. The strongest predictor of incontinence subtype was subtype history. The presence of the respective incontinence subtypes in 2004 and 2006 strongly predicted 2010 recurrence (odds ratio [OR] stress incontinence = 30.7, urgency OR = 47.4, mixed OR = 42.1).

Conclusions: Although the number of remissions was high, a previous history of incontinence subtypes predicted recurrence. Incontinence status is dynamic, but tends to recur over the longer term.

Keywords: Incidence; Mixed urinary incontinence; Predictors; Stress urinary incontinence; Urgency urinary incontinence.

Figure 1. Diagram of Urinary Incontinence and Incontinence Subtype Definitions

Figure 2. Urinary Incontinence Status: Transitions from Baseline to 2 year Follow-up

Transitions from incontinence status at baseline to 2 year follow-up (2004–6, 2006–8, 2008–10) UI status at baseline: No UI, UUI (Pure UUI without other subtypes), SUI (Pure SUI without other subtypes). 2 Year follow-up: Percentages of patients in each subtype at follow-up (years 2006, 2008 & 2010) are expressed as a range encompassing results for each of the years

Figure 3. History Predicts Occurrence of Urinary Incontinence Subtypes

X-Axis represents OR for incidence of UI subtype in 2010 Y-Axis represents UI subtypes (SUI, UUI and MUI) and UI subtype history. “Distant” history=UI subtype present in only 2004, “Recent” history=UI subtype present in only 2006, “Repetitive” history=UI subtype present in both 2004 & 2006.