Urinary incontinence

Urinary incontinence (UI) is any involuntary leakage of urine. It is a common and distressing problem, which may have a profound impact on quality of life. Urinary incontinence almost always results from an underlying treatable medical condition but is under-reported to medical practitioners. There is also a related condition for defecation known as fecal incontinence.

Physiology of continence
Continence and micturition involve a balance between urethral closure and detrusor muscle activity. Urethral pressure normally exceeds bladder pressure, resulting in urine remaining in the bladder. The proximal urethra and bladder are both within the pelvis. Intraabdominal pressure increases (from coughing and sneezing) are transmitted to both urethra and bladder equally, leaving the pressure differential unchanged, resulting in continence. Normal voiding is the result of changes in both of these pressure factors: urethral pressure falls and bladder pressure rises.

Causes

 * Polyuria (excessive urine production) of which, in turn, the most frequent causes are: uncontrolled diabetes mellitus, primary polydipsia (excessive fluid drinking), central diabetes insipidus and nephrogenic diabetes insipidus. Polyuria generally causes urinary urgency and frequency, but doesn't necessarily lead to incontinence.
 * Caffeine or cola beverages also stimulate the bladder.
 * Enlarged prostate is the most common cause of incontinence in men after the age of 40; sometimes prostate cancer may also be associated with urinary incontinence. Moreover drugs or radiation used to treat prostate cancer can also cause incontinence.
 * Disorders like multiple sclerosis, spina bifida, Parkinson's disease, strokes and spinal cord injury can all interfere with nerve function of the bladder.

Types

 * Stress incontinence, also known as effort incontinence, is due essentially to insufficient strength of the pelvic floor muscles.
 * Urge incontinence is involuntary loss of urine occurring for no apparent reason while suddenly feeling the need or urge to urinate.
 * Overflow incontinence: Sometimes people find that they cannot stop their bladders from constantly dribbling or continuing to dribble for some time after they have passed urine. It is as if their bladders were constantly overflowing, hence the general name overflow incontinence.
 * Mixed incontinence is not uncommon in the elderly female population and can sometimes be complicated by urinary retention, which makes it a treatment challenge requiring staged multimodal treatment.
 * Structural incontinence: Rarely, structural problems can cause incontinence, usually diagnosed in childhood (for example, an ectopic ureter). Fistulas caused by obstetric and gynecologic trauma or injury can lead to incontinence.  These types of vaginal fistulas include, most commonly, vesicovaginal fistula and, more rarely, ureterovaginal fistula. These may be difficult to diagnose. The use of standard techniques along with a vaginogram or radiologically viewing the vaginal vault with instillation of contrast media.
 * Functional incontinence occurs when a person recognizes the need to urinate but cannot make it to the bathroom. The urine loss may be large. Causes of functional incontinence include confusion, dementia, poor eyesight, poor mobility, poor dexterity, unwillingness to toilet because of depression, anxiety or anger, drunkenness, or being in a situation in which it is impossible to reach a toilet. People with functional incontinence may have problems thinking, moving, or communicating that prevent them from reaching a toilet. A person with Alzheimer's Disease, for example, may not think well enough to plan a timely trip to a restroom. A person in a wheelchair may be blocked from getting to a toilet in time. Conditions such as these are often associated with age and account for some of the incontinence of elderly women and men in nursing homes. Disease or biology is not necessarily the cause of functional incontinence. For example, someone on a road trip may be between rest stops and on the highway; also, there may be problems with the restrooms in the vicinity.
 * Bedwetting is episodic UI while asleep. It is normal in young children.
 * Transient incontinence is a temporary version of incontinence. It can be triggered by medications, adrenal insufficiency, mental impairment, restricted mobility, and stool impaction (severe constipation), which can push against the urinary tract and obstruct outflow.
 * Giggle incontinence is an involuntary response to laughter. It usually affects children.

Diagnosis
Patients with incontinence should be referred to a medical practitioner specializing in this field. Urologists specialize in the urinary tract, and some urologists further specialize in the female urinary tract. A urogynecologist is a gynecologist who has special training in urological problems in women. Gynecologists and obstetricians specialize in the female reproductive tract and childbirth and some also treat urinary incontinence in women. Family practitioners and internists see patients for all kinds of complaints and can refer patients on to the relevant specialists.

A careful history taking is essential especially in the pattern of voiding and urine leakage as it suggests the type of incontinence faced. Other important points include straining and discomfort, use of drugs, recent surgery, and illness.

The physical examination will focus on looking for signs of medical conditions causing incontinence, such as tumors that block the urinary tract, stool impaction, and poor reflexes or sensations, which may be evidence of a nerve-related cause.

A test often performed is the measurement of bladder capacity and residual urine for evidence of poorly functioning bladder muscles.

Other tests include:
 * Stress test – the patient relaxes, then coughs vigorously as the doctor watches for loss of urine.
 * Urinalysis – urine is tested for evidence of infection, urinary stones, or other contributing causes.
 * Blood tests – blood is taken, sent to a laboratory, and examined for substances related to causes of incontinence.
 * Ultrasound – sound waves are used to visualize the kidneys, ureters, bladder, and urethra.
 * Cystoscopy – a thin tube with a tiny camera is inserted in the urethra and used to see the inside of the urethra and bladder.
 * Urodynamics – various techniques measure pressure in the bladder and the flow of urine.

Patients are often asked to keep a diary for a day or more, up to a week, to record the pattern of voiding, noting times and the amounts of urine produced.

Urinary incontinence in women
Bladder symptoms affect women of all ages. However, bladder problems are most prevalent among older women. Up to 35% of the total population over the age of 60 years is estimated to be incontinent, with women twice as likely as men to experience incontinence. One in three women over the age of 60 years are estimated to have bladder control problems.

Bladder control problems have been found to be associated with higher incidence of many other health problems such as obesity and diabetes. Difficulty with bladder control results in higher rates of depression and limited activity levels.

Incontinence is expensive both to individuals in the form of bladder control products and to the health care system and nursing home industry. Injury related to incontinence is a leading cause of admission to assisted living and nursing care facilities. More than 50% of nursing facility admissions are related to incontinence.

Coital incontinence (CI) is urinary leakage that occurs during either penetration or orgasm and can occur with a sexual partner or with masturbation. It has been reported to occur in 10% to 24% of sexually active women with pelvic floor disorders.

Urinary incontinence in men
Men tend to experience incontinence less often than women, and the structure of the male urinary tract accounts for this difference. It is common with prostate cancer treatments. Both women and men can become incontinent from neurologic injury, congenital defects, strokes, multiple sclerosis, and physical problems associated with aging.

While urinary incontinence affects older men more often than younger men, the onset of incontinence can happen at any age. Recent estimates by the National Institutes of Health (NIH) suggest that 17 percent of men over age 60, an estimated 600,000 men, experience urinary incontinence, with this percentage increasing with age. Incontinence is treatable and often curable at all ages.

Incontinence in men usually occurs because of problems with muscles that help to hold or release urine. The body stores urine—water and wastes removed by the kidneys—in the urinary bladder, a balloon-like organ. The bladder connects to the urethra, the tube through which urine leaves the body.

During urination, muscles in the wall of the bladder contract, forcing urine out of the bladder and into the urethra. At the same time, sphincter muscles surrounding the urethra relax, letting urine pass out of the body. Incontinence will occur if the bladder muscles suddenly contract or muscles surrounding the urethra suddenly relax.

Treatment
The treatment options range from conservative treatment, behavior management, medications and surgery. In all cases, the least invasive treatment is started first. The success of treatment depends on the correct diagnoses in the first place.

Most treatment options are most appropriate for a specific underlying cause of the incontinence (though these can overlap if there is a mixed component to the incontinence.) However, some approaches (such as use of absorbent products) address the problem symptomatically, and can be applicable to more than one type. It is also sometimes possible to use a treatment for the pathophysiology of one type of incontinence to provide relief for an unrelated type of incontinence.

Absorbent pads and various types of urinary catheters may help those individuals who continue to experience incontinence. Some absorbent pads are not bulky like in the old days but are close fitting underwear with liners.

Men also can use an external urine collection device that is worn around the penis. These are traditionally referred to as condom or Texas catheters. These are not appropriate for men who are uncircumcised, have large or small anatomy or those who are have retracted anatomy. Condom catheter users frequently experience complications including urinary tract infections and skin breakdown. Newer products are available for men which do not have these associated complications. These include, "Liberty" which has recently reached one million devices without any reported urinary tract infections.

Absorbent products include shields, undergarments, protective underwear, briefs, diapers, adult diapers and underpads.

Hospitals often use some type of incontinence pad, a small but highly absorbent sheet placed beneath the patient, to deal with incontinence or other unexpected discharges of bodily fluid. These pads are especially useful when it is not practical for the patient to wear a diaper.

The most common form of urine management in hospitals is indwelling or Foley catheters. These catheters have an extremely high rate of infection and other associated secondary complications.

Urinary incontinence in children
Urination, or voiding, is a complex activity. The bladder is a balloonlike 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 girls as in boys.

Causes of 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 during sleep so that the need to urinate is lower. If the body does not 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 nighttime 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.

Obstructive sleep apnea
Nighttime incontinence may be one sign of another condition called obstructive sleep apnea, in which the child's breathing is interrupted during sleep, often because of inflamed or enlarged tonsils or adenoids. Other symptoms of this condition include snoring, mouth breathing, frequent ear and sinus infections, sore throat, choking, and daytime drowsiness. In some cases, successful treatment of this breathing disorder may also resolve the associated nighttime incontinence.

Structural problems
Finally, a small number of cases of incontinence are caused by physical problems in the urinary system in children. A condition known as urinary reflux or vesicoureteral reflux, in which urine backs up into one or both ureters, can cause urinary tract infections and incontinence. 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. An ectopic ureter, a misplacement of the ureter outside the bladder, can also commonly cause incontinence. In these cases, the incontinence can appear as a constant dribbling of urine.

Causes of 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. This form of incontinence occurs more often in girls than in boys.

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 may act together with infrequent voiding to produce daytime incontinence. These factors include a small bladder capacity, constipation and food containing caffeine, chocolate or artificial coloring.

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.

Children may also be affected by giggle incontinence, an involuntary response to laughter.

Growth and development
Most urinary incontinence fades away naturally. Here are examples of what can happen over time:


 * Bladder capacity increases.
 * Natural body alarms become activated.
 * An overactive bladder settles down.
 * Production of ADH becomes normal.
 * The child learns to respond to the body's signal that it is time to void.
 * Stressful events or periods pass.

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, which recently became available in pill form. Patients can also spray a mist containing desmopressin into their nostrils. Desmopressin is approved for use by children.

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:


 * Determining bladder capacity
 * Stretching the bladder (delaying urinating)
 * Drinking less fluid before sleeping
 * Developing routines for waking up

Unfortunately, none of the above has demonstrated proven success.

Techniques that may help daytime incontinence include:


 * Urinating on a schedule, such as every 2 hours (this is called timed voiding)
 * Avoiding caffeine or other foods or drinks that may contribute to a child's incontinence
 * Following suggestions for healthy urination, such as relaxing muscles and taking your time

Moisture alarms
At night, moisture alarms can awaken 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.