Female urinary incontinence: what the epidemiologic data tell us

The prevalence of urinary incontinence (UI) in women has been the subject of many epidemiologic studies. Since 1968 the field has accumulated sufficient data that we now know how stress UI and urge UI appear in populations categorized by race, age, parity, body mass index and other demographic factors. The first comprehensive study in the U.S., the MESA study, was done in 1983. For community-dwelling women 60 years or older, it came up with the now familiar figure of 38% in this age-group. Very similar figures have been found in other national populations, but there are great differences in sub-populations and also by type--stress, urge, or mixed UI. However, with all differences in prevalence acknowledged, no type of UI is unusual in a population of older women. This article delineates, with detailed discussion of individual studies, prevalence by type, age, race, obstetric and gynecologic-surgery history, and anatomic dysfunction, plus consideration of the effects of obesity and menopause on UI. The conclusion is that a problem so widespread is a candidate for prevention, and that the few trials in this direction should be augmented.