B19. Urinary incontinence and treatment

Urinary incontinence is the involuntary leakage of urine. There are multiple types:

• Stress urinary incontinence
• Urge urinary incontinence
• Overflow incontinence – the bladder fills, causing urine to overflow out
• Functional incontinence – due to mental or physical problems
• Mixed incontinence – features of more than one of the above

Stress and urge, as well as a mix of the two, account for 97% of cases of urinary incontinence.

Urinary incontinence is frequent in women. 15 – 55% of women are affected.

Risk factors

• Old age
• White ethnicity
• Obesity
• Menopause
• Multiparity
• Smoking and COPD
• Hysterectomy

Stress incontinence

Stress incontinence is the involuntary loss of urine in association with increased intraabdominal pressure, like laughing, coughing, lifting.

Urge incontinence

Urge incontinence is the involuntary loss of urine after feeling a sudden, urgent need to void. It’s sometimes called overactive bladder because it occurs due to a detrusor muscle which is constantly contracting. This reduces the capacity of the bladder, decreasing the amount of urine in the bladder necessary to give the urge to urinate. Patients usually have to go to the bathroom every 30 minutes, even during the night.

It is known simply as “urge” if there is a strong urge to urinate but no incontinence.

Possible causes are:

• UTI
• Pelvic organ prolapse
• Urinary tract tumour
• Urolithiasis

Diagnosis and evaluation

History is important, especially how many times the patient urinates every day. > 8 is usually abnormal.

Targeted questions and questionnaires can be used to evaluate and distinguish the type of urinary incontinence.

Voiding diaries are helpful. For 3 days, the patient fills in what and when they drink, the volume of urinary leakage, and provoking factors of incontinence. The volume of leakage can be estimated by using and weighing diapers before and after the leakage.

The patient should be examined for urinary retention, which is a sign of incomplete emptying. After urination, the residual urine volume should be assessed by ultrasound or catheterisation.

Physical examination includes checking for urine loss with Valsalva or coughing, as well as a neurological examination. It’s important to check the bulbocavernosus and anocutaneous reflexes, which evaluate the function of S2 – S4.

Other important examinations are:

• Evaluation for POP
• Q-tip test (see topic B17)
• Bimanual rectovaginal examination
• Urine analysis and culture
• Urodynamic studies

Urinary tract tumour should be excluded in cases of urge incontinence.

Treatment

The first line treatment is nonsurgical:

• Pelvic floor exercise (Kegel exercises)
• Peripheral electrical stimulation – if bladder innervation is poor
• Avoid caffeine
• Schedule voiding
• Local oestrogen replacement therapy

In case of stress incontinence, the second line can be surgical. A type of operation called a midurethral sling is the gold standard. This involves placement of a synthetic mesh to support the pelvic floor. There are two types of midurethral sling operations, retropubic tension-free vaginal tape (TVT) and tension-free vaginal tape obturator (TVT-O or TOT).

In case of urge incontinence, the second line can be medical:

• Muscarinic antagonists – block muscarinic acetylcholine receptors to decrease detrusor contraction
  • Solifenacine (Vesicare®)
  • Oxybutin
  • Tolterodine
  • Fesoterodine
• Beta-3 agonist
  • Mirabegron (Betmiga®)
• Intravesicular botulinum toxin injection