Overactive Bladder Flashcards
Definition of an overactive bladder (OAB)?
A chronic condition defined as urgency, with or without urge incontinence, usually with frequency or nocturia
What is the most common cause of overactive bladder?
Detrusor overactivity (DO)
How is DO diagnosed?
Urodynamic testing
Aetiology (causes) of OAB?
- Idiopathic in most cases
- Secondary to pelvic or incontinence surgery
- Rarely, neuropathic DO is found in the presence of conditions such as MS, spina bifida and upper motor neurone lesions
- OAB due to outflow obstruction is uncommon in women
Sx of OAB?
- Urinary frequency
- Urgency
- Urge incontinence
- Nocturia
What do provocative factors do? Give some examples?
Provocative factors trigger it. Some include;
- Cold weather
- Opening the front door
- Hearing running water
- Increased intra-abdominal pressure (e.g. coughing) can trigger bladder overactivity (but note this is different from USI, which can be misleading)
What Ix should be done?
- Urine culture
- Frequency / volume chart
- Urodynamics
Why is a urine culture done?
Exclusion of infection is mandatory, as Sx overlap with those of UTI
What will be seen on a frequency / urgency chart?
Increased diurnal frequency associated with urgency and episodes of urge incontinence
Nocturia a common Fx
What will be seen on urodynamics?
Involuntary detrusor contractions during the filling phase of the micturition cycle, which may be spontaneous or provoked
What other causes of OAB must be excluded for DO to be diagnosed?
- Metabolic abnormalities (e.g. diabetes or hypercalcaemia)
- Physical causes (e.g. prolapse or foecal impaction)
- Urinary pathology (e.g. UTI or interstitial cystitis)
About how many women are affected by OAB?
1 in 6
Does OAB incidence increase with age?
Yes
What is the 1st line Tx of OAB?
Behaviour Mx;
- Consume only 1-1.5L per day
- Avoid caffeine based drinks and alcohol
- Review drugs for diuretics and antipsychotics which can affect bladder function
Conservative Tx options?
- Behaviour therapy
- Bladder training
- Hypnotherapy and acupuncture
What is done in bladder retraining?
Suppress urinary urge and increase intervals between voiding.
Reported cure rates are between 44-90%
2 main medical Tx for OAB?
- Anticholinergics (1st line medical Tx)
2. Oestrogens
How do anticholinergics drugs work?
Block the parasympathetic nerves, thereby relaxing the detrusor muscle
Side effects of anticholinergics?
Can’t see, can’t pee, can’t spit, can’t shit;
- Dry mouth (up to 30%)
- Constipation, nausea, dyspepsia and flatulence
- Blurred vision, dizziness and insomnia
- Palpitation and arrhythmias
Contraindications to anticholinergics?
- Acute (narrow angle) glaucoma
- Myasthenia gravis
- Urinary retention or outflow obstruction
- Severe ulcerative colitis
- GI obstruction
How do oestrogens work?
Intravaginal oestrogens help to reduce vaginal atrophy in post-menopausal women.
Further Tx for OAB?
- Botulinium toxin A
- Neuromodulation and sacral nerve stimulation
- Surgery
Name some anticholinergics and their doses
- Oxybutinin (oral, 2.5-5mg, 1-4 times per day)
- Propiverine (oral, 15mg, 2-4 times/day)
- Solifenacin (oral, 5-10mg, daily)
- Tolterodine (oral, 2mg bd or 4mg od)
- Trospium (oral, 20mg bd)
- Fesoterodine (oral, 4 or 8mg od)
