Urinary incontinence is a very common condition of inadvertent loss of bladder control. It can cause significant distress and embarrassment to affected people. It is much more common in women and with advancing age.
What are the causes of urinary incontinence?
Urinary incontinence develops as the result of disruption to normal bladder storage or emptying functions.
There are a number of factors which may cause urinary incontinence or the development of urinary incontinence in women:
- Vaginal birth
- Giving birth to a child or children with a higher-than-average birth weight
- Giving birth to a high number of children
- Family history
- Increasing age: urinary incontinence becomes more common in middle age and most common in women over 70 years of age
- Stress incontinence: this is when urine leaks out at times when your bladder is under pressure, whilst there is concurrent weakness in the bladder neck (urethra). The urethra may not stay closed if the pelvic floor muscles are weak or damaged, and any sudden extra pressure on the bladder, such as coughing, laughing, sneezing or exercise can then cause urine to leak out of the urethra.
- Urge incontinence: this is the involuntary loss of urine following a sudden and very intense need to pass urine that cannot be delayed. This urgent and frequent need to pass urine is caused by inappropriate contraction of the muscles in the bladder wall, known as the detrusor muscles. The need to pass urine can be triggered by a sudden change of position, the sound of running water or even cold weather.
- Mixed incontinence: this is a combination of stress incontinence and urge incontinence. For example, a woman may leak urine on coughing or sneezing, and also experience a very intense urge to pass urine.
- Overflow incontinence (chronic urinary retention): this is when you’re unable to fully empty your bladder and instead pass small trickles of urine very often with leakage. You may also feel as though the bladder is never fully empty and cannot be emptied, even when trying to do so.
Diagnosis can be assisted with the use of a frequency/volume chart (bladder diary). This is a simple and practical method of obtaining objective quantification of your fluid intake, your functional bladder capacity and how often you empty your bladder (voiding). Frequency and times of voiding, voided volumes and leakage episodes (day and night) are all recorded for at least 24 hours and typically for three consecutive days.
Reagent-strip (dipstick) testing of urine for leukocyte esterase, nitrates, protein and blood is a cheap screening test for help with the diagnosis of urinary infection which can be cause of urinary symptoms. However, this test is not 100% accurate and any detected infection should ideally be confirmed by sending a urine sample to the laboratory.
Bladder ultrasound scan
An ultrasound scan of the bladder can be used to measure how much urine is left in the bladder after urinating. This is a helpful test if incomplete bladder emptying is suspected.
This is a test to assess the function of the bladder and urethra. This may include keeping a bladder diary for a few days prior to the test. The test aims to find the cause of urine leakage and confirm the diagnosis prior to undergoing further treatment.
Please see the urodynamic study section for more information.
Similar to prolapse, urinary incontinence treatment options depend on life circumstances, the causes of the urinary incontinence, type of urinary incontinence and other factors such as medical conditions. Conservative treatment options are always considered before surgical intervention.
Conservative treatment options for urinary incontinence
Some simple changes to lifestyle can help to reduce urinary incontinence:
- Caffeine intake reduction: Caffeine found in tea, coffee and many fizzy drinks can increase the amount of urine production and irritate the bladder. Reducing this and instead taking decaffeinated drinks can be of some benefit.
- Reduced excessive fluid intake: Fluid requirements depend on body size and perspiration. On average, however, 1.5 litres (eight glasses) of fluid a day should be adequate. Drinking too much or too little can affect the lower urinary tract (bladder and urethra).
- Weight loss: Excessive weight can place pressure on the bladder and pelvic floor. With weight loss, some patients find improvement with their urinary symptoms. Weight loss is also of benefit should surgical treatment be considered necessary.
Pelvic floor muscle training
The pelvic floor muscles behave like a valve, controlling the flow of urine out of the bladder. By improving the tone and strength of these muscles, urine leakage can be significantly reduced. Treatment is best guided by a Women’s Health Physiotherapist.
Please see the pelvic floor exercises section for more information.
Patients with urge incontinence tend to have high urinary frequency and a small bladder capacity. Bladder retraining involves learning techniques to gradually increase the length of time between each urination. In this way, bladder capacity should improve over time, as the bladder is trained to hold more urine. This retraining may be further aided with medication.
Bladder training may also be combined with pelvic floor muscle training, if the patient has mixed urinary incontinence.
Medication for urge incontinence
A group of medicines called anticholinergics can be used, if bladder retraining alone does not produce sufficient improvement with urinary urgency and urge incontinence. The commonly used preparations are Solifenacin, Tolterodine, Oxybutynin and Trospium. They work by blocking certain nerve receptors to the bladder, stopping the bladder muscle contraction and as a result increasing its capacity.
Response to this medication can vary, but in most patients there is less urinary urgency, less leakage and fewer trips to the toilet. Some may have limited improvement with medication alone. The medication may also take a few weeks to take effect. A follow-up appointment 4-6 weeks after starting the treatment will assess the patient’s response. If there is an inadequate improvement, the dose or type of medication will be revised.
Side effects with anticholinergic medications are common, but most patients find they are able to tolerate these if the treatment is otherwise effective. The most common side effects are a dry mouth and constipation. Usually the side effects are less noticeable at a lower dose, hence why the dosage is increased only gradually. However, there are differences between these medicines, and an individual patient may find that if one medicine causes troublesome side effects, switching to an alternative may suit better. If blurring of vision is noted, then the drug should be stopped.
A recent addition to the available medications for urinary urgency and urge incontinence is Mirabegron (Betmiga). This has different side effects as it works on different nerve receptors of the bladder. Mirabegron can be tried if anticholinergic drugs are not tolerated.
Vaginal oestrogen preparations
For menopausal women, topical vaginal oestrogen can help if there are significant irritative bladder symptoms of frequency, urgency and urge incontinence. It can also improve other vaginal problems such as dryness and discomfort due to vaginal atrophy. This treatment is best administered either as a pessary or cream, initially every night for a few weeks and then as a maintenance dose two or three times per week in the long term.