The Prevalence of Urinary Incontinence
Victor W Nitti, MD
Urinary incontinence is a significant health problem with considerable social and economic impact. It is important to distinguish between prevalence and incidence with regard to incontinence, and prevalence—the probability of having incontinence within a defined population at a defined point in time—is the more important when considering its impact and the utilization of healthcare resources. There are large variations in the severity and impact of incontinence, and its severity, frequency, and predictability all need to be considered when evaluating its effects on patients, The degree of bother is particularly significant when determining who will need treatment. Incontinence may be a result of bladder dysfunction, sphincter dysfunction, or a combination of both, but large-scale studies are not designed to determine the etiology. In young women, the prevalence of incontinence is usually low, but prevalence peaks around menopause, with a steady rise there-after into later life. Although the prevalence of stress and mixed (stress and urge) incontinence is higher than urge incontinence, the latter is more likely to require treatment. In women, moderate and severe bother have a prevalence ranging from about 3% to 17%. Severe incontinence has a low prevalence in young women, but rapidly increases at ages 70 through 80. In men, the prevalence of incontinence is much lower than in women, about 3% to 11% overall, with urge incontinence accounting for 40% to 80% of all male patients. Stress incontinence accounts for less than 10% of cases and is attributable to prostate surgery, trauma, or neurological injury. Incontinence in men also increases with age, but severe incontinence in 70- to 80-year-old men is about half of that in women. The most effective therapy for incontinence will rely on targeting the correct populations to be treated, which depends on how data is collected on prevalence and severity.
Urinary incontinence is a significant health problem in the United States and worldwide. It has a considerable social and economic impact on individuals and society. When discussing the epidemiology and impact of incontinence, it is important to distinguish its between prevalence and incidence.
Prevalence is the probability of having a disease or condition, in this case incontinence, within a defined population at a defined point in time. For example, prevalence would be the number of 60-year-old women in the United States in the year 2001 experiencing the symptom of incontinence.
Incidence, on the other hand, is the probability of developing a disease or condition during a defined period of time. Thus, the percentage of continent women in 2001 that will develop incontinence over the next year would define the incidence of incontinence over a 1-year period.
In most discussions on incontinence, especially when determining social impact and allocation of healthcare resources, prevalence is the more important parameter. Incidence can be important when discussing diseases or treatment where incontinence is a possible outcome, for example, the incidence of incontinence one year after radical prostatectomy or the incidence of incontinence in patients one year after stroke.