Incontinence

Definition | Aetiology | Pathophysiology | Risk Factors | Signs and Symptoms | Investigations | Management

Definition

Urinary incontinence is the involuntary loss of urine due to bladder dysfunction, sphincter weakness, or neurological impairment. It is classified into different types, each with distinct causes and management approaches.

Aetiology

Types of Urinary Incontinence:

• Stress Incontinence: weak pelvic floor muscles lead to leakage during coughing, sneezing, or exercise.
• Urge Incontinence (Overactive Bladder): sudden, intense need to urinate due to involuntary bladder contractions.
• Mixed Incontinence: combination of stress and urge incontinence.
• Overflow Incontinence: chronic urinary retention leads to involuntary dribbling.
• Functional Incontinence: inability to reach the toilet due to cognitive or physical impairment (e.g., dementia, arthritis).

Pathophysiology

• Stress Incontinence: increased intra abdominal pressure overcomes a weakened urethral sphincter.
• Urge Incontinence: overactive detrusor muscle causes involuntary bladder contractions.
• Overflow Incontinence: incomplete bladder emptying leads to constant leakage.
• Functional Incontinence: normal bladder function, but inability to reach the toilet in time.

Risk Factors

• Aging (weakened pelvic floor and reduced bladder capacity).
• Pregnancy and vaginal childbirth (damages pelvic floor muscles).
• Obesity (increases intra-abdominal pressure).
• Menopause (oestrogen deficiency weakens the urethral sphincter).
• Neurological conditions (e.g., multiple sclerosis, stroke, Parkinson’s disease).
• Pelvic surgery (e.g., prostatectomy, hysterectomy).
• Chronic cough (e.g., COPD, smoking).
• Medications (e.g., diuretics, alpha-blockers).

Signs and Symptoms

• Stress Incontinence: urine leakage when coughing, sneezing, laughing, or exercising.
• Urge Incontinence: sudden urgency followed by leakage before reaching the toilet.
• Overflow Incontinence: continuous dribbling, difficulty initiating urination.
• Functional Incontinence: difficulty accessing the toilet due to mobility or cognitive issues.
• Nocturia: frequent urination at night.

Investigations

• Bladder diary: records frequency, volume, and episodes of incontinence.
• Urinalysis: rules out infection, haematuria, and glycosuria.
• Post-void residual scan: assesses for urinary retention (overflow incontinence).
• Urodynamic studies: confirms detrusor overactivity in urge incontinence.
• Pelvic examination: assesses pelvic organ prolapse and sphincter tone.
• Neurological assessment: identifies underlying conditions like multiple sclerosis.

Management

1. Lifestyle Modifications:

• Weight loss (reduces intra abdominal pressure).
• Bladder training (gradual extension of voiding intervals).
• Pelvic floor muscle exercises (Kegel exercises) for stress incontinence.
• Reduce caffeine, alcohol, and fizzy drinks.
• Regular fluid intake to prevent bladder irritation.

2. Pharmacological Management:

Urge Incontinence (Overactive Bladder):

• Anticholinergics: oxybutynin, Tolterodine (reduces detrusor overactivity).
• Beta-3 agonists: mirabegron (preferred in elderly due to fewer cognitive side effects).

Stress Incontinence:

• Duloxetine: increases urethral sphincter tone.

Overflow Incontinence:

• Alpha-blockers (e.g., Tamsulosin): used in men with benign prostatic hyperplasia.
• Intermittent self-catheterisation: for significant urinary retention.

3. Surgical Management:

Stress Incontinence:

• Mid urethral sling (TVT/TOT): supports the urethra to prevent leakage.
• Colposuspension: lifts the bladder neck.
• Urethral bulking agents: used in frail patients.

Urge Incontinence (Refractory Cases):

• Botox injections: into the detrusor muscle.
• Sacral nerve stimulation: modulates bladder activity.

4. Management of Functional Incontinence:

• Assistive devices (e.g., commodes, easy-access clothing).
• Toileting schedules for patients with cognitive impairment.
• Carer education on continence management.