Overactive bladder

The kidneys make urine all the time. A trickle of urine is constantly passing to the bladder down the ureters, the tubes from the kidneys to the bladder. You make different amounts of urine depending on how much you drink, eat and sweat.

The bladder is made of muscle and stores the urine. It expands like a balloon as it fills with urine. The outlet for urine, the urethra, is normally kept closed. This is helped by the muscles beneath the bladder that sweep around the urethra, the pelvic floor muscles. 

Image credit: Wikimedia Commons

When a certain amount of urine is in the bladder, you become aware that the bladder is getting full. When you go to the toilet to pass urine, the bladder muscle squeezes (contracts) and the urethra and pelvic floor muscles relax.

Complex nerve messages are sent between the brain, the bladder, and the pelvic floor muscles. These tell you how full your bladder is, and tell the right muscles to contract or relax at the right time.

The cause is not fully understood. The bladder muscle seems to become overactive and contract when you don't want it to. Normally, the bladder muscle is relaxed as the bladder gradually fills up. As the bladder is gradually stretched, we get a feeling of wanting to pass urine when the bladder is about half full.

Most people can hold on quite easily for some time after this initial feeling until a convenient time to go to the toilet. However, in people with an overactive bladder, the bladder muscle seems to give wrong messages to the brain. The bladder may feel fuller than it actually is. The bladder contracts too early when it is not very full, and not when you want it to. This can make you suddenly need the toilet. In effect, you have much less control over when your bladder contracts to pass urine.

How common is the problem?

Approximately 600,000 New Zealanders have bladder control problems and experience leakage of urine. Overactive bladder is one of the causes of these symptoms and it can affect both men and women. In two large studies it was found that about 1 in 6 adults reported some symptoms of an overactive bladder. Symptoms vary in their severity. About 1 in 3 people with an overactive bladder have episodes of urge incontinence.

Incontinence in particular can be embarrassing for the person and many people do not seek the help that is available, thinking that nothing can be done for them. However, most men and women with overactive bladder can be helped, so it is important to talk about any bladder problems with your doctor.

• Urgency. This means that you get a sudden urgent desire to pass urine. You are not able to put off going to the toilet.
• Frequency. This means going to the toilet often – more than seven times a day. In many cases it is a lot more than seven times a day.
• Nocturia. This means waking to go to the toilet more than once at night.
• Urge incontinence occurs in some cases. This is a leaking of urine before you can get to the toilet when you have a feeling of urgency.

• Bladder training is a main treatment. This can work well in up to half of cases. 
• Pelvic floor exercises may also be advised in some cases.
• Medication may be advised instead of, or in addition to, bladder training.
• Surgery is sometimes recommended if the above methods have been unsuccessful.

Bladder training

The aim of bladder training is to slowly stretch the bladder so that it can hold larger and larger volumes of urine. In time, the bladder muscle should become less overactive and you should become more in control of your bladder. This means that more time can elapse between feeling the desire to pass urine, and having to get to a toilet. Leaks of urine are then less likely.

Bladder retraining is best undertaken with the guidance of a continence advisor or a practice nurse. The technique is to stay still and hold on until the feeling of urgency has passed, and then move to the toilet. Once you can do this, the aim is to lengthen the time between the urge passing and moving to the toilet. This technique requires persistence by you and support from your advisor or nurse.

You may find the urge to urinate happens at predictable times, such as on getting home or at the sound of running water. Recognising your triggers and not going to the toilet when triggers create the urge helps break the association and is another part of bladder retraining.

Helpful lifestyle changes include avoiding bladder irritants such as caffeine, alcohol and carbonated drinks, at least while you are attempting bladder retraining.

Pelvic floor exercises

Regular exercises to strengthen your pelvic floor muscles can help you to avoid leaking urine when your bladder muscles contract at unpredictable times. These should be learned at the same time as bladder retraining, with help from a continence advisor if needed.

See: Pelvic floor training for women and men

Medicines for overactive bladder

There are several medicines, called anticholinergics, that act on the bladder muscles to help reduce the frequency and severity of contractions. They can provide some immediate benefit and help you control your bladder while you learn the exercises and techniques described above. After a time, when you have regained bladder control, it may be possible to slowly reduce and stop using the medicines. A dry mouth or indigestion are possible side effects with these drugs.

Women can experience oestrogen hormone deficiency, which has been associated with urinary urgency and frequency. Vaginal oestrogen cream has been shown to reduce these symptoms.

The ‘simple’ combined approach described so far is known to be effective for about half of people with urge incontinence. If there has been no improvement despite guidance from a continence advisor, your doctor may refer you to a specialist, called a urologist, who can investigate the problem further and consider other treatments. One of these is botulinum toxin injections at sites within the bladder, a procedure that does not normally require a hospital stay and may provide relief for up to a year.  

Surgery

If the above treatments are not successful, surgery is sometimes suggested to treat overactive bladder syndrome. Procedures that may be used include:

Sacral nerve stimulation

An overactive bladder can be treated by sacral nerve stimulation. A small pulse generator device is implanted under the skin of the buttock to send a burst of electrical signals to the nerves that control the bladder.

Augmentation cystoplasty

In this operation, a small piece of tissue from the intestine is added to the wall of the bladder to increase the size of the bladder. However, not all people can pass urine normally after this operation. You may need to insert a catheter (a small tube) into your bladder in order to empty it.

Urinary diversion

In this operation, the ureters (the tubes from the kidneys to the bladder) are routed directly to the outside of your body. There are various ways that this may be done. Urine does not flow into the bladder. This procedure is only done if all other options have failed to treat your overactive bladder syndrome.

Getting to the toilet

Make this as easy as possible. If you have difficulty getting about, consider special adaptations like a handrail or a raised seat in your toilet. Sometimes a commode in the bedroom makes life much easier

Effects of caffeine and alcohol

Tea, coffee, cola, and some painkiller tablets contain caffeine. Caffeine has a diuretic effect and will make urine form more often. Caffeine may also directly stimulate the bladder to make urgency symptoms worse. It may be worth trying without caffeine for a week or so to see if symptoms improve. If symptoms do improve, you may not want to give up caffeine completely. However, you may wish to limit the times that you have a caffeine-containing drink. Also, you will know to be near to a toilet whenever you have caffeine.

In some people, alcohol may make symptoms worse. The same advice applies as with caffeine drinks.

Drink normal quantities of fluids

It may seem sensible to cut back on the amount that you drink so the bladder does not fill so quickly. However, this can make symptoms worse as the urine becomes more concentrated, which may irritate the bladder muscle. Aim to drink normal quantities of fluids each day. This is usually about two litres of fluid per day - about 6-8 cups of fluid, and more in hot climates and hot weather.

Go to the toilet only when you need to

Some people get into the habit of going to the toilet more often than they need. They may go when their bladder only has a small amount of urine so as "not to be caught short". This again may sound sensible, as some people think that symptoms of an overactive bladder will not develop if the bladder does not fill very much and is emptied regularly. However, again, this can make symptoms worse in the long run. If you go to the toilet too often the bladder becomes used to holding less urine. The bladder may then become even more sensitive and overactive at times when it is stretched a little. So, you may find that when you need to hold on a bit longer (for example, if you go out), symptoms are worse than ever.