Causes of Overactive Bladder
Overactive bladder (OAB) can be an embarrassing condition. It
has many causes. Finding the right treatment depends on knowing why you are experiencing OAB.
Urine is produced by the kidneys and stored in the bladder.
Bladder function requires a normal urinary tract and depends on intact
communication pathways between the nervous system and bladder muscle
In many cases, the exact cause of the involuntary
contraction associated with OAB is unknown. However, there are several known
factors that can cause involuntary contraction of the bladder muscle, improper
bladder function, and symptoms of OAB. There are also several risk factors that
can increase the chances that you will one day develop OAB. Knowing these risk
factors and causes will help you prevent the condition or develop the right
course of treatment after a diagnosis.
Certain risk factors associated with OAB like age and gender
are beyond your control. Others, like obesity, can be minimized with healthy
Although OAB can occur at any age, the risk of OAB increases
as you get older. According to the National Association for Continence
(NAFC), one in five adults over the age of 40 is affected by OAB or chronic
symptoms of urgency or frequency.
OAB is more likely to affect women than men. The NAFC says that 85 percent of people
suffering from OAB in the United States are women. This is largely because
menstruation, pregnancy, and menopause can lead to changes in estrogen levels
and weakened pelvic-floor muscles. This increases the risk of urge incontinence
as a symptom of OAB.
In men, an enlarged prostate (also related to aging) and
damage caused by prostate cancer surgery may lead to OAB symptoms.
Excess weight can increase pressure on the bladder. Obesity
could also decrease blood flow and nerve activity in the bladder, causing
control problems. Losing weight can often completely eliminate the symptoms of
Involuntary Bladder Contraction
While the exact cause of OAB
sometimes remains a mystery and is usually associated with age, at other times
a specific event can trigger the onset of OAB.
Certain neurological conditions may disrupt signals between
the nervous system and the bladder muscle and cause symptoms of OAB. These
- Parkinson’s disease
- multiple sclerosis (MS)
- spinal injury
Damage or Trauma
Nerve damage or trauma caused by surgery, certain therapies,
or trauma to the pelvis or abdomen can cause loss of control of bladder
muscles. This could be temporary — for instance, the moment of impact in a car
accident. It can also be longer term, as in the case of a pelvic injury.
Obstructions such as bladder stones and an enlarged prostate
can cause symptoms of OAB. An enlarged prostate can weaken the urinary stream
and create urinary urgency. It sometimes causes trouble with urination even
when the bladder feels full.
Other factors and medical conditions can cause symptoms
similar to those of OAB. These are often treated with different solutions than
Water pills prescribed for other diseases can create side
effects with OAB-like symptoms. Pills that have caffeine as an active
ingredient also have diuretic properties.
Infections of the urinary tract can cause
increased activity in the muscle of the bladder wall called the detrusor
muscle. This creates an overactive bladder and the urge to urinate more. Unlike
most forms of OAB, it can also cause painful urination and a burning sensation.
If this is the cause of your symptoms, your doctor will prescribe an antibiotic.
The OAB should be gone in a few days.
Various diseases or conditions can also affect or cause
incontinence and OAB. When this is the cause of your OAB, treating the
underlying disease can lessen symptoms. These conditions include kidney
disease, bladder tumors, and diabetes. Diabetes causes nerve damage (diabetic
neuropathy), which can affect the nerves that control bladder function and
cause urgency and frequency problems.
Menopause causes a sudden drop in the level of estrogen. Lower
estrogen levels may cause bladder and urethra muscles to weaken. The weakened muscles
can cause leakage from sudden urges associated with OAB (urge incontinence) or from sudden
movements such as laughing or sneezing (stress
During pregnancy, the uterus expands and can put pressure on
the bladder. This may cause sudden urges or incontinence. Women may also
experience incontinence problems after childbirth due to weakened pelvic-floor
muscles. This is a very common cause of OAB symptoms. It can often be treated
by Kegel exercises to strengthen the muscles.
Many things can make your OAB worse. The following are
considered triggers of OAB, and may temporarily cause increased symptoms.
- eating acidic foods like tomatoes and citrus
- excessive drinking of alcohol or caffeinated
- not drinking enough fluids
- low fiber intake
Understanding what causes OAB can help you prevent it. By
maintaining a healthy weight, for instance, you can avoid obesity-related OAB. If
you are already experiencing the symptoms, the cause of your OAB will help your
doctor choose the right course of treatment.