• Clinical science

Urinary incontinence

Abstract

Urinary incontinence is a common condition characterized by uncontrollable leakage of urine. Causes and presentation are variable. Stress incontinence, urge incontinence, and mixed incontinence are the most frequent forms. Urinary incontinence remains a grossly underreported condition in the US, affecting approximately 30–40% of the adults older than 65 years of age. The condition is twice as common in women as men. Diagnosis involves a detailed medical history, a voiding diary, physical examination, and diagnostic testing such as measurement of the bladder pressure (urodynamic examination). Treatment is determined based on the type of incontinence and its etiology, and usually involves measures such as pelvic floor physiotherapy, anti-incontinence devices, anticholinergics, or collecting devices. The prognosis in adequately treated cases is usually excellent, but, if left untreated, constant contact with leaked urine can cause urinary tract infections, dermatitis, and psychological distress.

Epidemiology

References:[1][2]

Epidemiological data refers to the US, unless otherwise specified.

Etiology

DIAPPERS: Delirium/confusion, Infection, Atrophic urethritis/vaginitis, Pharmaceutical, Psychiatric causes (especially depression), Excessive urinary output (hyperglycemia, hypercalcemia, CHF), Restricted mobility, Stool impaction.

References:[3][4]

Overview

Type of incontinence Pathophysiological mechanism Key features Treatment
Stress incontinence
  • Urinary leakage on activities that increase intra-abdominal pressure
Urge incontinence
  • Inflammatory conditions or neurogenic disorders → sphincter dysfunction, detrusor overactivity or overactive bladder autonomous contractions of the detrusor muscle and premature initiation of a normal micturition reflex
  • Strong, sudden sense of urgency, followed by involuntary leakage
Mixed incontinence
  • May have any of the clinical features above
Total incontinence
  • Complete loss of sphincter function (due to previous surgery, nerve damage, metastasis) or abnormal anatomy (fistula between urinary tract and skin)
  • Urinary leakage occurs at all times, with no associated preceding symptoms or specific trigger activity
Overflow incontinence (overflow bladder)
  • Frequent, involuntary intermittent/continuous dribbling of urine in the absence of an urge to urinate
  • Occurs only when the bladder is full
  • Often occurs with changes in position
  • Acute settings: intermittent catheterization
  • Timed voiding for day to day management
  • Treatment of underlying condition (see also “Treatment” in urinary retention)

Enuresis risoria

(giggle incontinence)

  • Unknown; not related to stress or detrusor weakness
  • Affects children
  • Involuntary complete voiding triggered by giggling or laughing
  • Voiding behavior is otherwise normal (not a feature of enuresis).
  • No specific treatment available; usually resolves spontaneously
Further causes of urinary incontinence
  • Voiding and/or storage dysfunction, intermittent voiding, urinary retention
  • Irregular, small volume incontinence without an associated urge to void (sometimes referred to as reflex incontinence)

Neural control of micturition: parasympathetic nervous systemS2S4 ventral root → inferior hypogastric plexus → contraction of the detrusor muscle → voluntary relaxation of the external urethral sphincter muscle via the pudendal nerve → micturition!

References:[5][6][7][8][9]

Diagnostics

Basic diagnostic testing

  • Detailed medical history (including medication)
  • Voiding diary to assess frequency and volume of micturition
  • Neurological, vaginal, and rectal examination
  • Laboratory tests
  • Sonography
    • Quantification of residual urine after micturition
    • Renal ultrasound
  • Quantification of leaked urine: pad test

Additional diagnostic testing

  • Micturating cysto-urethrogram (MCU) to detect morphological abnormalities
  • Urodynamic examination to measure bladder pressure and urethral closure pressure
  • Cystoscopy to rule out tumors and vesicorectal or vesicovaginal fistulae
  • MRI to identify pelvic floor defects
  • See also “Diagnostics” in stress incontinence and urge incontinence.

References:[6][10]

Treatment

General principles of treatment of urinary incontinence

  • Modify contributing factors (e.g., drugs) and treat reversible causes.
  • Physical measures to prevent leakage
    • Absorbent products
    • Catheterization
    • Urethral occlusion
    • Pessaries and penile compression devices
  • Lifestyle modifications
    • Weight loss
    • Dietary changes (e.g., decrease consumption of alcohol, caffeine, carbonated drinks)
    • Smoking cessation
  • Behavioral therapies and exercises
  • Management of constipation
  • Topical vaginal estrogen in postmenopausal patients with vaginal atrophy

Other treatment options depend on the form of urinary incontinence; see “Overview” section above as well as stress incontinence and urge incontinence.

References:[5][7]

Complications

References[11]

We list the most important complications. The selection is not exhaustive.