Urinary Incontinence

Involuntary leakage of urine

Aetiology

Risk factors

• Higher incidence in females

• Caucasian > Afro-Carribbean

• Genetic predisposition

• Neurological disorders - spinal cord injury, stroke, MS, Parkinson's

• Antatomical disorders - vesicovaginal fistula, ectopic ureter in girls, urethral diverticulum, urethral fistula, bladder extrophy, epispadias

• Childbirth - vaginal delivery, increasing parity, pregnancy

• Pelvic, perineal and prostate surgery

• Radical pelvic radiotherapy

• Diabetes

Promoting factors

• Smoking - causing cough

• Obesity

• Infection - UTI

• Increased fluid intake

• Poor nutrition

• Ageing

• Congnitive deficit

• Poor mobility

• Oestrogen deficiency

Pathophysiology

Stress urinary incontinence (SUI)

• Leakage on effort or exertion, sneezing or coughing

• Occurs as a result of bladder neck/urethral hypermobility and/or neuromuscular defects causing intrinsic sphincter deficiency

• Urine leaks whenever urethral resistance is exceeded by increased abdominal pressure

Urge urinary incontence

• Leakage accompanied or immediately preceded by urgency

• May be due to bladder overactivity (detrusor instability) or less commonly due to pathology that irritates the bladder (infection, tumour, stone)

Mixed urinary incontinence (MUI)

• Combination of SUI and urge urinary incontinence

Other types

• Bedwetting in elderly men usually indicates high-pressure chronic retention

• Post-micturition dribble - happens in men immediately after leaving the toilet and is due to urine pooling in bulbar urethra

• A constant leakage of urine suggests a fistulous communication between the bladder (usually) and vagina (e.g. due to surgical injury at the time of hysterectomy or Caesarian section) or rarely the presence of an ectopic ureter draining into the vagina

Clinical presentation

Symptoms

• History - type, triggering factors, frequency and degree of bother, risk factors

• Red flags:
• Pain
• Haematuria
• Recurrent UTI
• Significant voiding/obstructive symptoms
• History of pelvic surgery/radiotherapy

Signs

• Ask patient to cough or strain and look for:
• Vaginal wall prolapse
• Uterine or vaginal vault descent
• Urinary leakage

• Internal pelvic examination to assess voluntary pelvic floor muscle strength and bladder neck mobility

• Inspect the vulva for oestrogen deficiency causing vaginal atrophy

• Examine abdomen for palpable bladder (urinary retention)

• Neurological examination to assess gait, anal reflex, perineal sensation and lower limb function

• DRE to exclude constipation, a rectal mass and to test anal tone

• Red flags - new neurological deficit, haematuria, urethral/pelvic/bladder mass, suspected fistula

Investigations

• Frequency/volume chart

• Urinalysis +/- culture

• Flow rate and post-void residue

• Pad testing

• Further investigations for complex cases - bloods, imaging, cystoscopy, cystometry

Management

Conservative management

• Pelvic floor exercises

• Lifestyle modification - weight loss, stop smoking, avoid constipation, modify fluid intake

• Biofeedback - a technique where ability and strength of pelvic floor contraction is fed back to patient as a visual and auditory signal

• Medication for urge incontenance:
• Anticholinergic medication e.g. tolterodine (inhibit contraction)
• β-adrenoceptor agonists (induce detrusor relaxation)

Surgical management

• Injection therapy - injection of bulking materials into the bladder neck and periurethral muscles to increase outlet resistance; main indication is for female stress incontinence secondary to intrinsic sphincter deficiency with normal bladder function

• Retropubic suspension - used to treat female stress incontinence predominantly caused by urethral hypermobility

• Suburethral tapes and slings
• Tapes not currently used due to complications

• Artificial urinary sphincter - used for moderate to severe SUI secondary to urethral sphincter deficiency in patients with normal bladder capacity and complicance, more common in men