CHAPTER 47
Urinary Incontinence
Urinary incontinence is the uncontrollable loss of urine.
Urinary incontinence can be caused by a bladder infection, certain drugs, brain and spinal cord disorders, diseases that affect the nerves leading to and from the bladder, conditions in the lower urinary tract such as an enlarged prostate, and conditions that impair mental function or mobility.
Symptoms depend on the type of incontinence but may include a sudden uncontrollable urge to urinate or constant leak of urine.
Doctors ask about the pattern of urine leakage, may ask the person to keep a record of episodes of incontinence, and do some basic examinations to help determine the cause and treatment.
Some general measures, including urinating at regular intervals, regulating fluid intake, and practicing pelvic muscle exercises, help many people.
Other treatments are available including various drugs and surgical procedures.
Urinary incontinence affects as many as 1 in 3 older people, and fewer, but many, younger people. In most age groups, urinary incontinence is more common among women than men.
Urinary incontinence differs somewhat among age groups. Incontinence experienced by younger adults tends to begin suddenly, and it often resolves quickly with little or no treatment. Also, when younger adults experience incontinence, they usually maintain control without leakage for most of their episodes of urination. Older adults are often more frequently and severely affected. In addition, incontinence is less likely to resolve quickly or without treatment in older adults.
Although urinary incontinence is common, highly treatable, and very often curable, it is often not diagnosed or treated. People often live with incontinence without seeking professional help because they are afraid, embarrassed, or mistakenly believe it is a normal part of aging. A person with incontinence often feels isolated or depressed. In addition, urinary incontinence is often a reason for institutionalization because of the substantial burden it places on caregivers. More than 50% of nursing home residents are incontinent.
Urinary incontinence can lead to many complications. For example, incontinence that is not properly managed can contribute to the development of bladder and kidney infections. Particularly among older adults, incontinence can also increase the risk of skin rashes and pressure sores (because urine can irritate the skin) and falls (because an incontinent person may fall when rushing to use the toilet).
Control of Urination
The kidneys constantly produce urine, which flows through two tubes (the ureters) to the bladder, where urine is stored. The lowest part of the bladder (the neck) is encircled by a muscle (the urinary sphincter) that remains contracted to close off the channel that carries urine out of the body (the urethra), so that urine is retained in the bladder until it is full.
When the bladder is full, messages travel along nerves from the bladder to the spinal cord. The messages are then relayed to the brain, and the person becomes aware of the urge to urinate. A person who has control of urination can consciously and voluntarily decide whether to release the urine from the bladder or to hold it for a while. When the decision is made to urinate, the sphincter muscle relaxes, allowing urine to flow out through the urethra, and the bladder wall muscles contract to push the urine out. Muscles in the abdominal wall and floor of the pelvis can be contracted to increase the pressure on the bladder.
Types and Causes
Incontinence can be categorized according to whether it is temporary (transient incontinence) or caused by a long-standing problem (established incontinence).
A bladder infection is the most common cause of transient incontinence. Other reversible factors that can contribute to incontinence include conditions that result in confusion (for example, a severe infection such as pneumonia) or impaired mobility (for example, because of a leg or hip fracture). Additional causes of transient incontinence include excess intake of alcohol or beverages that contain caffeine and conditions that can result in irritation of the bladder or urethra, such as atrophic vaginitis or severe constipation.
Established incontinence may be caused by brain and spinal cord disorders such as stroke, Alzheimer’s disease, and multiple sclerosis; diseases that affect the nerves leading to and from the bladder such as diabetes; conditions in the lower urinary tract such as an enlarged prostate; and conditions that permanently impair mental function or mobility.
Urinary incontinence can also be categorized into five basic types based on the pattern of symptoms:
Urge
Stress
Overflow
Functional
Mixed
Urge Incontinence: Urge incontinence is an abrupt and intense urge to urinate that is usually followed by an uncontrollable loss of urine. People with urge incontinence usually have little time to get to the bathroom before they have an “accident.” An illness or injury that interferes with mobility makes it even harder for a person to get to the bathroom quickly. Use of a diuretic can aggravate the problem.
Urge incontinence is the most common type of established incontinence in older people and often has no clear cause. In most older people with urge incontinence, the bladder muscles are overactive (the muscles contract involuntarily before the bladder is full). Part of the cause of persistent urge incontinence may be changes in the part of the brain in the frontal lobe that inhibits urination. These changes, which disrupt the nervous system’s ability to inhibit the bladder, may accompany brain disorders, especially stroke and dementia. Chronic overactivity of the bladder—overactive bladder—is common among older people and causes the abrupt and intense urge to urinate as well as frequent urination during the day and night. In postmenopausal women, a lack of estrogen contributes to atrophic vaginitis (thinning of the vaginal tissue), which causes irritation and can worsen urinary urgency and contribute to incontinence.
SPOTLIGHT ON AGING
Several changes occur with aging that may affect a person’s ability to control urination. With aging, the maximum amount of urine that the bladder can hold (bladder capacity) tends to decline. Also, the ability to postpone urination after feeling the need to urinate may decrease. In addition, the amount of urine remaining in the bladder after urination is finished (residual urine) increases with aging.
In women, the urethra shortens and its lining becomes thinner as the level of estrogen declines during menopause. These changes decrease the ability of the urinary sphincter to close tightly.
In men, the rate of urine flow out of the bladder and through the urethra slows, especially when the prostate gland enlarges. This change becomes common as men age.
All of these age-related changes increase the odds that people will develop incontinence as they get older.
DRUGS THAT MAY CAUSE OR WORSEN URINARY INCONTINENCE
| TYPE OF DRUG | EXAMPLES | EFFECTS |
| Alcohol | Beer, liquor, and wine | Increases urine production |
| Alpha-adrenergic agonists | Nasal decongestants that contain pseudoephedrine | Tighten the urinary sphincter Can cause urinary retention and overflow incontinence |
| Alpha-adrenergic blockers | Doxazosin, prazosin, and terazosin | Relax the bladder outlet and urethra Can cause stress incontinence in women |
| Angiotensin-converting enzyme (ACE) inhibitors | Benazepril and captopril | Can cause cough and worsen stress incontinence |
| Caffeine | Coffee, tea, colas, and chocolate | Increases urine production |
| Cholinesterase inhibitors | Donepezil | Can increase bladder contractility and contribute to urge incontinence |
| Diuretics | Bumetanide, furosemide, theophylline, and thiazides | Increase urine production |
| Drugs with anticholinergic effects* | Antihistamines, benztropine, some antidepressants (such as amitriptyline, desipramine, and nortriptyline), and some antipsychotics (such as haloperidol, risperidone, thioridazine, and thiothixene) | Interfere with bladder contraction, sometimes causing urinary retention and overflow incontinence Can worsen constipation, worsening urge or overflow incontinence |
| Hormonal therapy in women (given orally) | Estrogen-progestin combination therapy, which is used to treat hot flashes and other menopausal symptoms | When estrogen-progestin therapy is taken by mouth, new or worsening incontinence in some women When topical estrogen is applied locally by cream or other methods, less severe symptoms of incontinence in some women |
| Opioids | Codeine, morphine, and oxycodone | Interfere with bladder contraction, sometimes causing urinary retention and overflow incontinence Can worsen constipation and thus worsen urge or overflow incontinence |
| Sedatives and sleep aids (hypnotics) | Diazepam, eszopiclone, flurazepam, lorazepam, and zoldipem | Can cause slow mobility and make people less aware of the need to urinate |
| *Drugs with anticholinergic effects can have side effects such as confusion, memory problems, blurred vision, constipation, dry mouth, and retention of urine. | ||
Stress Incontinence: Stress incontinence is the uncontrollable loss of small amounts of urine, such as with coughing, straining, sneezing, lifting heavy objects, or performing any maneuver that suddenly increases pressure within the abdomen. Stress incontinence is the most common type of incontinence among young and middle-aged women. It can be caused by weakness of the urinary sphincter, which sometimes results from childbirth, pelvic surgery, or an abnormal position of the urethra or uterus. In postmenopausal women, a lack of estrogen reduces the urethra’s resistance to urine flow. In men, stress incontinence may follow prostate surgery if the upper part of the urethra or the bladder neck is injured. In both men and women, obesity can cause or worsen stress incontinence because extra weight stresses the bladder.
Some people with severe stress incontinence have nearly constant urine loss (sometimes referred to as total incontinence). In adults, this usually occurs because the urinary sphincter does not close adequately.
Overflow Incontinence: Overflow incontinence is the uncontrollable leakage of small amounts of urine from a bladder that does not empty well. Overflow incontinence is usually caused by some type of blockage or by weak bladder contraction caused by nerve damage or bladder muscle weakness. When urine flow is blocked or the bladder muscles can no longer contract, the bladder becomes overfilled and enlarged. Pressure increases in the bladder until small amounts of urine dribble out.
Did You Know…
People often live with incontinence because they mistakenly believe it is a normal part of aging.
In men, an enlarged prostate can block the opening into the urethra from the bladder. Less commonly, blockage is caused by narrowing of the bladder neck or the urethra (urethral stricture), which may occur after prostate surgery or radiation therapy for prostate cancer. In men and women, constipation can cause overflow incontinence if stool fills the rectum to the point of putting pressure on the bladder neck and urethra. A number of drugs that affect the brain or spinal cord or that interfere with nerve messages—such as drugs with anticholinergic effects (for example, benztropine, most antihistamines, some antidepressants, and some antipsychotics) and opioids—may impair bladder contractions and cause overflow incontinence. Nerve damage that paralyzes the bladder (neurogenic bladder) can also cause overflow incontinence. Diabetes mellitus can also cause a form of neurogenic bladder and overflow incontinence.
Functional Incontinence: Functional incontinence refers to urine loss resulting from the inability (or sometimes unwillingness) to get to a toilet. The most common causes are conditions that cause immobility, such as stroke or severe arthritis, and conditions that interfere with mental function, such as dementia due to Alzheimer’s disease. In rare situations, people may become so depressed or otherwise emotionally disturbed that they do not go to the toilet. This is sometimes referred to as psychogenic incontinence.
Mixed Incontinence: Mixed incontinence involves more than one type of incontinence. The most common type of mixed incontinence occurs in older women, who often have a mixture of urge and stress incontinence. Also, many older people have both urge and functional incontinence.
Diagnosis
Ideally, a doctor asks about incontinence. If not, however, the person should bring up the subject. The doctor asks specific questions about the history of the problem. The doctor also asks how much the incontinence is affecting the person’s quality of life and ability to function and how long incontinence has been occurring. People with urinary incontinence may be asked to record the pattern of urination for at least 3 days (a “bladder diary”). This diary can help doctors evaluate the cause of the incontinence. Useful information might include the following:
What symptoms are associated with the incontinence? For example, before urination or episodes of incontinence, is there an abrupt and intense urge to urinate? If so, how much time typically passes after the urge to urinate before urination begins?
Do episodes of incontinence occur with laughing, coughing, sneezing, or bending?
When episodes of incontinence occur, are undergarments typically damp or are they soaked? This can help estimate how much urine leaked.
Does there seem to be a relationship between urination and taking drugs or drinking alcohol or caffeinated beverages? The time the person eats, drinks, takes drugs, and sleeps helps determine whether urination is related to any of these activities.
What is the frequency of urination or episodes of incontinence during a typical day? A typical night? If people urinate frequently at night but in much smaller amounts than when awake, the cause may be that sleep is disturbed. That is, people urinate because they are awake rather than being awakened to urinate.
A physical examination can provide valuable information. A rectal examination can confirm whether the person is severely constipated, determine whether the nerves to the bladder are damaged, and, in men, determine whether the prostate is enlarged. A pelvic examination in women can help identify problems that may contribute to or cause incontinence, such as atrophy of the lining of urethra, prolapse of the bladder (cystocele), and damage affecting the nerves to the bladder. Examination may also help determine if a problem with mental function or immobility is contributing to incontinence.
Stress incontinence is sometimes diagnosed simply by observing the loss of urine while the person is coughing or straining. The amount of urine left in the bladder after urination (residual urine) can be measured using ultrasonography or urinary catheterization (placing a small tube called a catheter into the bladder). A large amount of residual urine indicates an obstruction or a problem with nerves or the bladder muscle, which may indicate overflow incontinence. Urinalysis is performed to determine whether an infection is present.
Doctors often test urine for evidence of a urinary tract infection and test blood for evidence of impaired kidney function. They may also test for the bladder’s ability to empty completely by using an ultrasound or inserting a catheter in the bladder (a test called post-void residual determination). For some people, special tests during urination (urodynamic evaluation) and cystoscopy may be helpful. Urodynamic tests measure the pressure in the bladder at rest and when filling. A catheter is inserted through the urethra into the bladder and water is passed through the catheter while the pressure within the bladder is recorded. Normally, the pressure increases only when the bladder is relatively full. In some people, pressure builds in sudden spasms or rises too sharply before the bladder is completely filled. The pattern of pressure change helps the doctor determine the type of incontinence and the best treatment. The rate of urine flow can also be measured. This measurement can help determine whether urine flow is obstructed and whether the bladder muscles can contract strongly enough to expel the urine. Additionally, the function of the urethral sphincter muscle, which helps retain urine in the bladder, can be assessed. A weak urethral sphincter muscle may cause or contribute to incontinence. Cystoscopy involves looking directly into the bladder with a flexible viewing tube (similar to colonoscopy) to identify abnormalities that may be contributing to the incontinence and related symptoms.
Treatment
Treatment varies according to the type and cause of incontinence. Most people can be either cured or helped considerably.
People should receive education about bladder functioning, the effects of drugs and fluid intake, and bladder and bowel habits. Prevention of constipation is especially important because a full bowel can irritate the bladder more. Treatment often requires only taking some simple steps to change behavior, such as deliberately urinating at regular intervals—every 2 to 3 hours (sometimes called scheduled voiding)—to keep the bladder relatively empty. Avoiding fluids that may irritate the bladder, such as beverages that contain caffeine, may help. People should drink adequate amounts of fluids (for many people, six to eight 8-ounce [or about 250-milliliter] glasses a day) to prevent the urine from becoming too concentrated—which can irritate the bladder. Drugs that adversely affect bladder function can often be stopped. For people taking diuretics, the timing of the dose can be adjusted so that the person can be close to a bathroom when the drug takes effect.
Specially designed incontinence pads and undergarments can protect the skin and enable people to remain dry, comfortable, and socially active. These items are unobtrusive and readily available.
Bladder training techniques, which include pelvic muscle (Kegel) exercises (see page 1545), can be very helpful, particularly for urge or stress incontinence. The exercises involve repeatedly contracting the muscles many times a day to build up strength and learning to use the muscles properly in situations that cause incontinence, such as coughing. Nurses or physical therapists can help teach these exercises. People who have trouble learning how to contract these muscles may find biofeedback helpful. With biofeed-back, electrodes are temporarily placed near the sphincter muscles at the outside of the anus. The electrodes transmit signals that display muscle activity and allow the person to better identify and contract the appropriate muscles.
Drugs may also be useful for certain types of incontinence. It may seem confusing that some drugs that can cause incontinence, such as alpha-adrenergic agonists, alpha-adrenergic blockers, and drugs with anticholinergic effects, can also be used to treat incontinence. Doctors choose drugs based on the type of incontinence and the symptoms that are most troublesome. For example:
Alpha-adrenergic agonists tighten the urinary sphincter, which can help prevent stress incontinence caused by a weak urinary sphincter.
Alpha-adrenergic blockers relax the urinary sphincter. Relaxing the urinary sphincter can be helpful in men who have urinary symptoms associated with an enlarged prostate.
Drugs with anticholinergic effects decrease bladder contractions, which can help people with urge incontinence by decreasing the strong urge to urinate.
Urge Incontinence: Episodes of urge incontinence often can be prevented by urinating at regular intervals before the urge occurs (scheduled voiding). Pelvic muscle (Kegel) exercises, which can strengthen bladder muscles and help inhibit involuntary urination, may also help. Drugs that relax the bladder, such as the anticholinergic drugs used to treat incontinence, are the ones most commonly prescribed. The two most commonly used drugs of this class are oxybutynin and tolterodine. Both can be taken once a day. Oxybutynin can be used as a skin patch that is applied twice a week, or the drug can be administered directly into the bladder. Newer drugs in this category include solifenacin, darifenacin, and trospium. Alternatively, botulinum toxin, which paralyzes muscles, can be injected into the bladder to help relax the overactive bladder muscles. Although this treatment is too new to be recommended routinely, results with it so far suggest that it may be effective for 6 to 9 months. Although all of these drugs can help reduce bladder irritability and the strong urge to urinate, they have potential side effects, such as dryness of the mouth, constipation, gastroesophageal reflux, and even retention of urine.
Stress Incontinence: For people with stress incontinence, urinating frequently to avoid a full bladder and pelvic muscle (Kegel) exercises are often helpful. In women with stress incontinence and thinning of the vagina or urethra due to a lack of estrogen, applying estrogen cream or inserting a rubber ring with estrogen or estrogen tablets into the vagina may be helpful. Risks and benefits should be discussed thoroughly (see page 1517). However, using estrogen cream or an estrogen ring or tablet does not have as many side effects or as much risk as does taking estrogens by mouth. Other drugs that help tighten the sphincter, such as pseudoephedrine and duloxetine, may also help. Incontinence pads may be used to absorb the small amount of urine that usually leaks during stress.
SOME DRUGS USED TO TREAT URINARY INCONTINENCE
| EXAMPLES | SOME SIDE EFFECTS | COMMENTS |
| Drugs with anticholinergic effects | ||
| Darifenacin Hyoscyamine Oxybutynin Solifenacin Tolterodine Trospium |
Dry mouth, constipation, worsening of glaucoma, confusion, memory problems, worsening of heartburn, and urinary retention | Can decrease the strong urge to urinate in people with urge incontinence Equally effective overall, although some people may respond better to one drug than to another Effective in older and younger people Oxybutynin more likely to have side effects, especially dry mouth |
| Serotonin-norepinephrine reuptake inhibitor (an antidepressant) for women | ||
| Duloxetine | Nausea | Used to treat stress incontinence due to weak bladder outlet Not yet widely used in the United States |
| Alpha-adrenergic agonist for women | ||
| Pseudoephedrine | Insomnia, anxiety, awareness of heart beats, high blood pressure, and, in men, urinary retention | Used to treat stress incontinence due to a weak bladder outlet Not recommended for people with heart disorders, high blood pressure, glaucoma, or diabetes |
| Alpha-adrenergic blockers for men | ||
| Alfuzosin Doxazosin Prazosin Tamsulosin Terazosin |
Low blood pressure (especially after standing up), fatigue, weakness, and dizziness | Used to relieve blockage of the bladder in men with urge or overflow incontinence May take days to a few weeks to become effective May increase the rate of urine flow If taken with drugs that lower blood pressure, can cause blood pressure to become too low With alfuzosin and tamsulosin, less of an effect on blood pressure than the other drugs listed |
| 5-Alpha-reductase inhibitors for men | ||
| Dutasteride Finasteride |
Decreased libido and erectile dysfunction | Used to treat an enlarged prostate that is blocking urine flow out of the bladder in men with urge or overflow incontinence May enable men to postpone or avoid prostate surgery May take months to become effective |
More severe cases of stress incontinence that do not respond to other treatments can be corrected with surgery. By using any of several procedures, doctors can strengthen or tighten the tissues around the urethra. Injections of bulk-forming agents, such as collagen, around the urethra are effective in some people. A urinary sphincter that does not close adequately may be replaced with an artificial one.
Overflow Incontinence: For overflow incontinence caused by an enlarged prostate or other blockage, surgery is usually necessary. Several procedures are available to remove part or all of the prostate. Dutasteride or finasteride, when taken over a period of months, can reduce the size of the prostate or stop its growth, so that surgery can be avoided or deferred. Drugs that relax the prostate, such as alfuzosin, doxazosin, prazosin, terazosin, and tamsulosin, may help the bladder empty more efficiently.
When the cause of overflow incontinence is weak contraction of the bladder muscles, drugs are usually not helpful. Gentle pressure applied by squeezing the lower abdomen with the hands just over the bladder may help, especially for people who can empty the bladder but have difficulty emptying it completely. In some cases, a catheter may need to be inserted into the bladder to drain the bladder and prevent complications, such as recurring infections and kidney damage. The catheter may be placed permanently, or it may be inserted and removed several times a day (intermittent catheterization).
Functional Incontinence: Treatment for functional incontinence involves regular toileting assistance. For example, another person can remind the incontinent person to urinate on a schedule, usually every 3 to 4 hours, so that the bladder is emptied before episodes of incontinence can occur (prompted scheduled voiding). Sometimes, a bedside commode or a hand-held urinal is useful for people who have difficulty getting to the toilet. If depression is a contributing factor, it should be treated. The use of garments and pads is also helpful; however, a person should not become unnecessarily dependent on them.
Incontinence in Children
The pattern of incontinence helps the doctor determine the likely cause.
The child’s history and results of a physical examination, laboratory tests, and imaging tests help the doctor determine the specific cause.
Treatment includes behavioral changes, dietary changes, and sometimes drugs.
Incontinence in children has different causes and treatment than that in adults. Incontinence can occur at night (bed-wetting, also called nocturnal enuresis—see page 1746). Nocturnal enuresis is more common among boys, and children usually outgrow this type of incontinence by age 9. Incontinence during the daytime is sometimes called diurnal enuresis. Diurnal enuresis tends to be more common among girls and has a number of different causes.
Causes
The pattern of incontinence helps the doctor determine the likely cause. If the child has never had a consistent dry period during the day, the doctor considers the possibility of a birth defect, an anatomic abnormality, or certain behaviors that can lead to incontinence. A spinal cord defect such as spina bifida can cause nerve damage to the bladder and lead to incontinence, but such a defect is usually obvious. Some infants have a birth defect that prevents the bladder or urethra from developing completely, leading to nearly constant urine loss (total incontinence). Another type of birth defect causes the ureter to end outside the bladder, causing incontinence. Some children have an over-active bladder that easily spasms, or they have difficulty emptying their bladder.
Certain behaviors can lead to daytime incontinence, especially in girls. Such behaviors include urinating infrequently and urinating using an incorrect position, which can cause urine to leak into the vagina, then dribble out after standing. Some girls experience bladder spasm when laughing, resulting in “giggle incontinence.”
If the child has been dry for a long time and the incontinence is new, the doctor considers conditions that intermittently cause difficulties. These include constipation, diet, emotional stress, infections, and sexual abuse. Bacterial urinary tract infections and viral infections that lead to bladder irritation (viral cystitis) are common infectious causes. To prevent urine from leaking, many children with incontinence cross their legs or use other postures, which may increase the chance of developing a urinary tract infection. Sexually active adolescents can have urinary difficulties from certain sexually transmitted diseases. Caffeine and acidic juices, such as orange and tomato juice, can irritate the bladder and lead to leakage of urine. Children with diabetes mellitus or diabetes insipidus (a disorder resulting in excessive amounts of dilute urine) can develop incontinence because these disorders result in production of excessive amounts of urine.
Diagnosis
Sometimes doctors can diagnose the cause by the child’s symptoms and the results of an examination. To check for an infection, a urinalysis and sometimes a urine culture is done. To check for diabetes mellitus and diabetes insipidus, doctors use blood and urine tests to check sugar and electrolyte levels. If a birth defect is suspected, an ultrasound examination of the kidneys and bladder and x-rays of the spine may be necessary. A special x-ray of the bladder and kidneys, called a voiding cystourethrogram, may also be necessary. With this test, a dye is injected into the bladder using a catheter, which shows the anatomy of the urinary tract, as well as the direction of urine flow.
Treatment
Treatment depends on the cause of the incontinence. An infection is usually treated with antibiotics. Relieving and preventing constipation, urinating at 2- to 3-hour intervals, using a technique called biofeedback for an overactive bladder, and changing other behaviors may be effective depending on the cause. Dietary changes can help decrease bladder irritants. If behavioral interventions are not effective, certain drugs (such as oxybutynin) may help if the cause is bladder spasm. Children with birth defects or anatomic abnormalities may need surgery, drugs, or intermittent catheterization.