An Introduction to Urinary Incontinence--Part I of V

Michael J. Borrie, BSc, MB, ChB, FRCPC
Chair, Division of Geriatric Medicine, The University of Western Ontario

Prevalence studies of urinary incontinence in the elderly report widely-varying rates from 4.5-44% in healthy, elderly women to 4.6-24% in healthy, elderly men. The prevalence in institutionalized people ranges from 22-90%.1

Choice of definition, wording of the questionnaire and study population contribute to this variability. The International Continence Society has defined incontinence as a condition in which involuntary loss of urine is a social or hygienic problem and is objectively demonstrated.2 Based on the symptom complex, urinary incontinence is characterized as urge, stress, mixed, overflow, functional, or iatrogenic.

Urgency urinary incontinence is the most common type and is divided into sensory or motor urgency. Ambulatory or longer-term urodynamic studies have demonstrated involuntary detrusor contractions and calls into question the notion of sensory urgency. A new classification of overactive bladders has been proposed but has not yet been resolved.3 Detrusor instability is commonly associated with neurologic conditions such as stroke or Parkinson's Disease. It can also accompany prostatic obstruction.