Urinary Incontinence Definition
Urinary incontinence is common, affecting about 1 out of 3 older people. Some people are incontinent every time they urinate, whereas many others are incontinent intermittently. Many people live with incontinence without seeking medical help because they fear that it indicates a more serious illness or they are embarrassed by it. Others mistakenly believe incontinence to be a normal part of aging and assume that nothing can be done for it. On the contrary, urinary incontinence is never normal and, when it does occur, is often treatable and curable.
Urinary incontinence is not only a problem in itself but also can lead to many other problems and complications, particularly among older people. For example, incontinence can cause a person to avoid activities and interactions with others, which can lead to isolation and depression. In addition, incontinence can increase the risk of skin rashes and pressure sores (from urine irritating the skin) as well as falls (from attempts to reach the toilet quickly).
Urinary Incontinence Causes and Symptoms
Aging itself does not cause urinary incontinence, but changes that occur with aging can increase the risk of developing urinary incontinence by interfering with a person’s ability to control urination. For example, the maximum amount of urine that the bladder can hold (bladder capacity) decreases. The ability to postpone urination decreases. More urine remains in the bladder after urination (residual urine), partly due to less effective squeezing of the bladder muscle. In postmenopausal women, the urinary sphincter does not hold back urine in the bladder as effectively, because the decrease in estrogen levels after menopause leads to shortening of the urethra and thinning and fragility (atrophy) of its lining. Also, urine flow through the urethra slows. In men, urine flow through the urethra may be impeded by an enlarged prostate gland, eventually leading to bladder enlargement.
Urinary incontinence has many possible causes. Some causes, such as a bladder infection, a broken hip, or delirium, can bring on incontinence suddenly and abruptly. Other causes, such as an enlarged prostate in men or dementia, gradually interfere with control of urination until incontinence results. Incontinence may resolve and never recur. Alternatively, it may persist, recurring sporadically or, in some cases, frequently.
Urinary Incontinence Types
Many experts try to categorize incontinence according to the basic cause of the problem. The categories or types that most experts agree on are urge incontinence, stress incontinence, overflow incontinence, functional incontinence, and mixed incontinence.
Urge incontinence is an abrupt and intense urge to urinate that cannot be suppressed, followed by an uncontrollable loss of urine. The amount of urine lost may be small or large. People with urge incontinence usually have very little time to get to the bathroom before they have an “accident.” Most people with urge incontinence urinate more frequently, not only during the day but also at night (nocturia). The combination of urgency, increased frequency of urination, and increased urination during the night is often referred to as an overactive bladder, whether or not the combination leads to incontinence.
Urge incontinence is the most common type of persistent incontinence in older people. The cause of bladder overactivity and urge incontinence is usually unknown. Stroke, dementia, or other disorders that affect the ability of the brain or spinal cord (for example, lumbar spinal stenosis) to inhibit bladder contractions when there is no opportunity to urinate contribute to urge incontinence. Conditions that irritate the bladder, such as atrophic vaginitis in women, prostate enlargement in men, or severe constipation, can also contribute to urge incontinence.
Stress incontinence is the uncontrollable loss of small amounts of urine when coughing, straining, sneezing, or lifting heavy objects or during any activity that suddenly increases pressure within the abdomen. This increased pressure overcomes the resistance of the closed urinary sphincter. Urine then flows into and through the urethra. Stress incontinence is common in women but uncommon in men.
Any condition or event that weakens and reduces resistance of the urinary sphincter or urethra can cause stress incontinence. Childbirth, for example, can weaken the urinary sphincter, as can surgery involving organs or structures in the pelvis, such as the uterus (for example, hysterectomy). If a portion of the bladder loses its support of fibrous connective tissue and bulges into the wall of the vagina (a condition called cystocele), the lowest part of the bladder changes shape. If the shape of the bladder changes, the position of the urethra can change where it connects with the bladder, which then interferes with and weakens the urinary sphincter. In postmenopausal women, a lack of estrogen weakens the urinary sphincter’s ability to hold back urine flow by allowing the lining of the urethra to become thinner and more fragile, a condition called atrophic urethritis. In men, stress incontinence may follow prostate surgery if the urinary sphincter is injured. In both men and women, obesity can cause or worsen stress incontinence because extra weight adds additional pressure on the bladder.
Overflow incontinence is the uncontrollable leakage of small amounts of urine, usually caused by some type of blockage or by weak contractions of the bladder muscle. When urine flow is blocked or the bladder muscle can no longer contract, urine is retained in the bladder (urinary retention), and the bladder enlarges. Pressure in the bladder continues to increase until small amounts of urine dribble out. The increased pressure in the bladder can also damage the kidneys.
In older men, an enlarged prostate can block the urethra. Less commonly, scar tissue narrows or sometimes even blocks the lowest part of the bladder, where it connects to the urethra, or blocks the urethra itself (urethral stricture). Such narrowing or blockage may occur after prostate surgery. In men and women, severe constipation or stool impaction can cause overflow incontinence if stool fills the rectum to the point of putting pressure on the lower portion of the bladder, the urinary sphincter, or the urethra. Nerve damage that paralyzes the bladder (a condition commonly called neurogenic bladder) can also cause overflow incontinence. Stroke and diabetes mellitus can paralyze the bladder, leading to overflow 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 lead to immobility, such as stroke or severe arthritis, and conditions that interfere with mental function, such as dementia due to Alzheimer’s disease. In rare cases, people become so depressed that they do not go to the toilet (psychogenic 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. Urge incontinence and functional incontinence occur together in people with severe dementia, Parkinson’s disease, stroke, and other disabling neurologic disorders.
Urinary Incontinence Diagnosis
The information collected by asking about urination and incontinence can help doctors determine the type, severity, and cause of the problem and develop an appropriate treatment plan. Doctors often ask the following questions:
- How long has incontinence been occurring?
- With episodes of incontinence, are undergarments typically just damp, or are they soaked?
- Before urination or episodes of incontinence, is there an abrupt and intense urge to urinate? How much time typically passes before urination begins after feeling an urge to urinate?
- Do certain events or actions seem to trigger a need to urinate (such as the sound of running water, washing hands, exercise)?
- Do episodes of incontinence occur with laughing, coughing, sneezing, or bending?
- What is the frequency of urination or episodes of incontinence during a typical day? A typical night?
- How difficult is it to start urinating? Once urination begins, is the urine flow interrupted?
- Does there seem to be a relationship between urination and taking drugs or drinking alcohol or caffeinated beverages?
- How has incontinence affected the ability to carry out daily activities?
A person with urinary incontinence may be asked to keep a diary in which urinary habits are recorded for at least 3 days. This diary can help the doctor evaluate how often incontinence occurs and how much urine is being lost during episodes of incontinence. The diary may also help the doctor determine the cause of incontinence.
A physical examination can provide valuable information. A rectal examination can confirm whether the person is severely constipated or if stool is impacted. Nerve damage contributing to or causing incontinence may be detected by an examination of sensation and reflexes in the lower body. In women, a pelvic examination can help identify problems that may contribute to or cause incontinence, such as atrophy of the lining of the urethra and dropping down of the bladder into the vagina. 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 with ultrasound. Alternatively, the amount of residual urine can be measured with a small tube (catheter) that is placed into the bladder (urinary catheterization). A large amount of residual urine may indicate overflow incontinence, the result of urine flow being blocked or the bladder not contracting adequately. Examination of the urine with a microscope (a urinalysis) can help determine whether an infection is present.
Special tests performed during urination (urodynamic evaluation) are helpful in some cases. These 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 slowly and steadily. In some people, pressure increases in spurts 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 muscle can contract strongly enough to expel the urine. In some cases, a doctor may look into the bladder with a flexible viewing tube called a cystoscope.
Urinary Incontinence Treatment
Treatment varies according to the type and cause of incontinence. In most cases, incontinence can be cured or reduced considerably.
Sometimes treatment involves only education and some simple behavioral changes. The person learns about bladder functioning and the effects of drugs and fluid intake. The person also learns how to establish bladder and bowel habits that promote control over urination, such as being patient and not rushing urination and bowel movements. The person is advised to avoid fluids that may irritate the bladder, such as caffeinated beverages, or to reduce intake. Drinking six to eight 8-ounce glasses of noncaffeinated fluids a day is recommended to prevent the urine from becoming too concentrated-which can irritate the bladder as well.
If specific disorders or drugs are causing or contributing to incontinence, treatment involves an effort to eliminate or minimize these factors. Drugs that reduce squeezing of the bladder muscle often can be discontinued. 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.
Urge incontinence: People with urge incontinence are encouraged to urinate at regular intervals-typically about every 2 to 3 hours-before the urge occurs. This type of training, sometimes called habit or bladder training, keeps the bladder relatively empty, thus reducing the likelihood of incontinence. Another approach involves learning to resist urination for gradually longer periods once an urge to urinate is felt. The goal is urination every 3 to 4 hours without incontinence.Performing pelvic muscle exercises (Kegel exercises) can be very helpful. These exercises involve repeatedly contracting the pelvic muscles many times a day to build up strength. Drugs that relax the bladder by reducing muscle contractions may help. The two most commonly used drugs are oxybutynin and tolterodine. The long-acting forms of these drugs can be taken once a day.. Recently, the use of a pacemaker whose wires are implanted into the spinal cord has proved useful in some people who have multiple episodes of urge incontinence (more than 50 per day).
People with stress incontinence, like those with urge incontinence, are encouraged to urinate about every 2 to 3 hours to avoid a full bladder. Pelvic muscle exercises (Kegel exercises) are usually helpful.
In women whose stress incontinence seems to be due to atrophy of the urethra, applying estrogen cream inside the vagina or to the area immediately surrounding the opening of the urethra may help. Estrogen cream is more likely to help if other drugs that help tighten the urinary sphincter, such as pseudoephedrine, are also taken.
Many people with severe stress incontinence that does not respond to treatment benefit from surgery. Surgery may involve lifting up the bladder and strengthening the part that connects with the urethra. Injections of collagen around the urethra are effective in some cases. In rare cases, surgery may be performed to insert an artificial sphincter in place of a urinary sphincter that does not close adequately.
When the cause is a blockage of urine flow, the incontinence is treated whenever possible by eliminating or reducing the blockage. Drugs that relax the urinary sphincter, such as terazosin and tamsulosin, quickly counteract some of the blockage caused by the enlarged prostate. Finasteride, when taken over a period of months, can reduce the size of the prostate or stop its growth. Alternatively, men with overflow incontinence caused by an enlarged prostate can undergo surgery to remove all or part of the prostate.
Regardless of the cause, in some cases of overflow incontinence, a catheter must be inserted into the bladder to drain it and to prevent complications such as recurring infections and kidney damage. Insertion and removal of a catheter several times a day (intermittent catheterization) is recommended rather than a catheter that remains in place indefinitely (permanent indwelling catheterization). Intermittent catheterization is less likely to cause infection. People can insert a catheter themselves (intermittent self-catheterization) but must be capable of remembering to do it and have good hand dexterity.