Purpose of review: Overactive bladder epidemiology is a rapidly evolving field. The new terminology of lower urinary tract function, introduced in 2002, modified the definitions of all four components of overactive bladder. In the same year, the lack of specific information on overactive bladder prevalence was identified and consequently new studies were launched and recently published.
Recent findings: Following the new terminology, overactive bladder now includes both a purely sensory disorder and a condition related to an altered bladder behaviour. Studies conducted in selected countries and populations suggested comparable prevalence data worldwide, although the syndrome is considered to be underreported. 'Urge' is now considered the cornerstone symptom of overactive bladder. Recent epidemiological data confirm the increase in overactive bladder prevalence with age and suggest that most diet and lifestyle factors are not associated with the condition, with the exception of body mass index. Among the symptoms, urge and urinary incontinence were considered to be more significantly related to patients' quality of life compared with frequency and nocturia. The socioeconomic consequences of the overactive bladder syndrome were recently estimated in a large US study and a total cost of 12.6 billion US dollars was calculated.
Summary: Specific data on overactive bladder epidemiology are now available, providing new evidence about its relevance as a clinical issue. Both wet and dry overactive bladder cause a significant reduction in quality of life. In our daily practice we have to consider that overactive bladder is frequently underreported as patients believe that no treatment is available and urinary incontinence is considered a natural consequence of aging.