Urinary Incontinence

 

• Definitions and epidemiology

  Stress incontinence

  • Urine leaks with increases in intra-abdominal pressure e.g. cough, sneeze.
  • Commoner than urge incontinence.
  • Mostly affects women.

  Detrusor overactivity

  • Aka detrusor instability, overactive bladder, irritable bladder.
  • Usually leads to urge incontinence – a sudden, unstoppable need to go – but 25% of cases lead to stress incontinence.
  • Affects men and women.

• History

  Important aspects:

  • Determine if it is stress, urge, or mixed.
  • Ask them to keep a 3 day bladder diary.
  • What is the impact? Consider a quality of life stool such as ICIQ, BFLUTS, or I-QOL.
  • Ask about risk factors for stress incontinence in women: parity, prolapse (and check on examination by asking for a cough).

• Differential diagnosis

  • UTI
  • Diabetes
  • Pelvic mass pressing on bladder
  • Prolapse
  • Voiding difficulty: usually neurological, including detrusor weakness.
  • Neurological disease.
  • Atrophic vaginitis.

• Investigations

  • Urine dipstick to exclude UTI and diabetes.
  • Bladder scan or catheterisation to measure post-void residual if there are signs of voiding dysfunction.

• Management

  Lifestyle changes:

  • Weight loss

  Stress incontinence:

  • Pelvic floor exercises from physio.
  • Intravaginal oestrogen (but not oral) if post-menopausal.
  • Medical: pseudoephedrine (sympathomimetic), duloxetine (SNRI).
  • Anti-incontinence pessary to support bladder.
  • Surgery if severe: synthetic mid-urethral sling, colposuspension, or autologous rectus fascial sling.

  Overactive bladder:

  • Avoid caffeine.
  • 6 weeks bladder training to increase time between voiding.
  • Antimuscarinics (oxybutynin, tolterodine, solifenacin, darifenacin) or β3 agonists (mirabegron).
  • Further options: bladder wall botox, percutaneous sacral nerve stimulation.

  Other options:

  • Pads and pull-ups are not a long term solution, but can improve quality of life until definitive treatment is found.
  • Intermittent or indwelling catheterisation for those with urinary retention which does not respond to treatment.

• Oxybutynin

  Mechanism

  Antagonist of all muscarinic ACh receptor types, preventing parasympathetic contraction of the detrusor muscle.

  Dose

  Start low, then work up until effective.

  Side effects

  Anticholinergic effects:

  • Dry mouth.
  • Blurred vision.
  • Nausea
  • Headache
  • Constipation, diarrhoea, and/or abdominal pain.