Introduction
Urinary incontinence (UI) is a common problem, affecting around 4-5% of the population. It is more common in elderly females.
Classification
Classification
- overactive bladder (OAB)/urge incontinence: due to detrusor overactivity
- stress incontinence: leaking small amounts when coughing or laughing
- mixed incontinence: both urge and stress
- overflow incontinence: due to bladder outlet obstruction, e.g. due to prostate enlargement
Aetiology
Risk factors
- advancing age
- previous pregnancy and childbirth
- high body mass index
- hysterectomy
- family history
Clinical features
Investigations
Initial investigation
- bladder diaries should be completed for a minimum of 3 days
- vaginal examination to exclude pelvic organ prolapse and ability to initiate voluntary contraction of pelvic floor muscles ('Kegel' exercises)
- urine dipstick and culture
- urodynamic studies
Management
Management depends on whether urge or stress UI is the predominant picture. If urge incontinence is predominant:
If stress incontinence is predominant:
- bladder retraining (lasts for a minimum of 6 weeks, the idea is to gradually increase the intervals between voiding)
- bladder stabilising drugs: antimuscarinics are first-line. NICE recommend oxybutynin (immediate release), tolterodine (immediate release) or darifenacin (once daily preparation). Immediate release oxybutynin should, however, be avoided in 'frail older women'
- mirabegron (a beta-3 agonist) may be useful if there is concern about anticholinergic side-effects in frail elderly patients
If stress incontinence is predominant:
- pelvic floor muscle training: NICE recommend at least 8 contractions performed 3 times per day for a minimum of 3 months
- surgical procedures: e.g. retropubic mid-urethral tape procedures