URINARY
INCONTINENCE IN CHILDREN
In
the United States, at least 13 million people have problems holding
urine until they can get to a toilet. This loss of urinary control
is called "urinary incontinence" or just "incontinence."
Although it affects many young people, it usually disappears naturally
over time, which suggests that incontinence, for some people, may
be a normal part of growing up. No matter when it happens or how
often it happens, incontinence causes great distress. It may get
in the way of a good night's sleep and is embarrassing when it happens
during the day. That's why it is important to understand that occasional
incontinence is a normal part of growing up and that treatment is
available for most children who have difficulty controlling their
bladders.
How
Does the Urinary System Work?
Urination,
or voiding, is a complex activity. The bladder is a balloon like
muscle that lies in the lowest part of the abdomen. The bladder
stores urine, then releases it through the urethra, the canal that
carries urine to the outside of the body. Controlling this activity
involves nerves, muscles, the spinal cord, and the brain.
The
bladder is made of two types of muscles: the detrusor, a muscular
sac that stores urine and squeezes to empty, and the sphincter,
a circular group of muscles at the bottom or neck of the bladder
that automatically stay contracted to hold the urine in and automatically
relax when the detrusor contracts to let the urine into the urethra.
A third group of muscles below the bladder (pelvic floor muscles)
can contract to keep urine back.
A
baby's bladder fills to a set point, then automatically contracts
and empties. As the child gets older, the nervous system develops.
The child's brain begins to get messages from the filling bladder
and begins to send messages to the bladder to keep it from automatically
emptying until the child decides it is the time and place to void.
Failures
in this control mechanism result in incontinence. Reasons for this
failure range from the simple to the complex.
Incontinence
happens less often after age 5: About 10 percent of 5-year-olds,
5 percent of 10-year-olds, and 1 percent of 18-year-olds experience
episodes of incontinence. It is twice as common in boys as in girls.
What
Causes Nighttime Incontinence?
After
age 5, wetting at night--often called bedwetting or sleepwetting--is
more common than daytime wetting in boys. Experts do not know what
causes nighttime incontinence. Young people who experience nighttime
wetting tend to be physically and emotionally normal. Most cases
probably result from a mix of factors including slower physical
development, an overproduction of urine at night, a lack of ability
to recognize bladder filling when asleep, and, in some cases, anxiety.
For many, there is a strong family history of bedwetting, suggesting
an inherited factor.
Slower
Physical Development
Between
the ages of 5 and 10, incontinence may be the result of a small
bladder capacity, long sleeping periods, and underdevelopment of
the body's alarms that signal a full or emptying bladder. This form
of incontinence will fade away as the bladder grows and the natural
alarms become operational.
Excessive
Output of Urine During Sleep
Normally,
the body produces a hormone that can slow the making of urine. This
hormone is called antidiuretic hormone, or ADH. The body normally
produces more ADH at night so that the need to urinate is lower.
If the body doesn't produce enough ADH at night, the making of urine
may not be slowed down, leading to bladder overfilling. If a child
does not sense the bladder filling and awaken to urinate, then wetting
will occur.
Anxiety
Experts
suggest that anxiety-causing events occurring in the lives of children
ages 2 to 4 might lead to incontinence before the child achieves
total bladder control. Anxiety experienced after age 4 might lead
to wetting after the child has been dry for a period of 6 months
or more. Such events include angry parents, unfamiliar social situations,
and overwhelming family events such as the birth of a brother or
sister.
Incontinence
itself is an anxiety-causing event. Strong bladder contractions
leading to leakage in the daytime can cause embarrassment and anxiety
that lead to wetting at night.
Genetics
Certain
inherited genes appear to contribute to incontinence. In 1995, Danish
researchers announced they had found a site on human chromosome
13 that is responsible, at least in part, for nightime wetting.
If both parents were bedwetters, a child has an 80 percent chance
of being a bedwetter also. Experts believe that other, undetermined
genes also may be involved in incontinence.
Structural
Problems
Finally,
a small number of cases of incontinence are caused by physical problems
in the urinary system in children. Rarely, a blocked bladder or
urethra may cause the bladder to overfill and leak. Nerve damage
associated with the birth defect spina bifida can cause incontinence.
In these cases, the incontinence can appear as a constant dribbling
of urine.
What
Causes Daytime Incontinence?
Daytime
incontinence that is not associated with urinary infection or anatomic
abnormalities is less common than nighttime incontinence and tends
to disappear much earlier than the nighttime versions. One possible
cause of daytime incontinence is an overactive bladder. Many children
with daytime incontinence have abnormal voiding habits, the most
common being infrequent voiding.
An
Overactive Bladder
Muscles
surrounding the urethra (the tube that takes urine away from the
bladder) have the job of keeping the passage closed, preventing
urine from passing out of the body. If the bladder contracts strongly
and without warning, the muscles surrounding the urethra may not
be able to keep urine from passing. This often happens as a consequence
of urinary tract infection and is more common in girls.
Infrequent
Voiding
Infrequent
voiding refers to a child's voluntarily holding urine for prolonged
intervals. For example, a child may not want to use the toilets
at school or may not want to interrupt enjoyable activities, so
he or she ignores the body's signal of a full bladder. In these
cases, the bladder can overfill and leak urine. Additionally, these
children often develop urinary tract infections (UTIs), leading
to an irritable or overactive bladder.
Other
Causes
Some
of the same factors that contribute to nighttime incontinence mayact
together with infrequent voiding to produce daytime incontinence.
These factors include
Sometimes
overly strenuous toilet training may make the child unable to relax
the sphincter and the pelvic floor to completely empty the bladder.
Retaining urine (incomplete emptying) sets the stage for urinary
tract infections.
What
Treats or Cures Incontinence?
Growth
and Development
Most
urinary incontinence fades away naturally. Here are examples of
what can happen over time:
Many
children overcome incontinence naturally (without treatment) as
they grow older. The number of cases of incontinence goes down by
15 percent for each year after the age of 5.
Medications
Nighttime
incontinence may be treated by increasing ADH levels. The hormone
can be boosted by a synthetic version known as desmopressin, or
DDAVP. Users, including children, spray a mist containing desmopressin
into their nostrils, where the drug enters the bloodstream. Researchers
are developing a pill version of this drug.
Another
medication, called imipramine, is also used to treat sleepwetting.
It acts on both the brain and the urinary bladder. Unfortunately,
total dryness with either of the medications available is achieved
in only about 20 percent of patients.
If
a young person experiences incontinence resulting from an overactive
bladder, a doctor might prescribe a medicine that helps to calm
the bladder muscle. This medicine controls muscle spasms and belongs
to a class of medications called anticholinergics.
Bladder
Training and Related Strategies
Bladder
training consists of exercises for strengthening and coordinating
muscles of the bladder and urethra, and may help the control of
urination. These techniques teach the child to anticipate the need
to urinate and prevent urination when away from a toilet. Techniques
that may help nighttime incontinence include
- Drinking
less fluid before sleeping
Unfortunately,
none of the above has demonstrated proven success.
Techniques
that may help daytime incontinence include
Moisture
Alarms
At
night, moisture alarms can wake a person when he or she begins to
urinate. These devices include a water-sensitive pad worn in pajamas,
a wire connecting to a battery driven control, and an alarm that
sounds when moisture is first detected. For the alarm to be effective,
the child must awaken or be awakened as soon as the alarm goes off.
This may require having another person sleep in the same room to
awaken the bedwetter.
Incontinence
is also called enuresis.
Points
to Remember
-
Treatments
include waiting, dietary modification, moisture alarms, medications,
and bladder training.
Reprinted
with permission from:
National institute
of Diabetes & Digestive & Kidney Diseases
3 Information Way
Bethesda, MD 20892-3580
Back
To The Diagnostic Categories
|