Stress incontinence

Alternative names
Incontinence - stress

Definition
Stress incontinence is an involuntary loss of urine that occurs during physical activity, such as coughing, sneezing, laughing, or exercise.

Stress incontinence is a bladder storage problem in which the strength of the urethral sphincter is diminished, and the sphincter is not able to prevent urine flow when there is increased pressure from the abdomen.

Stress incontinence may occur as a result of weakened pelvic muscles that support the bladder and urethra, or because of malfunction of the urethral sphincter. Prior trauma to the urethral area, neurological injury, and some medications may weaken the urethra.

Sphincter weakness may occur in men following prostate surgery or in women after pelvic surgery. Stress incontinence is often seen in women who have had multiple pregnancies and vaginal childbirths, or who have pelvic prolapse (protrusion of the bladder, urethra, or rectal wall into the vaginal space), with cystocele, cystourethrocele, or rectocele.

Studies have documented that about 50% of all women have occasional urinary incontinence, and as many as 10% have frequent incontinence. Nearly 20% of women over age 75 experience daily urinary incontinence.

Stress urinary incontinence is the most common type of urinary incontinence in women. Risk factors for stress incontinence include female sex, advancing age, childbirth, smoking, and obesity. Conditions that cause chronic coughing, such as chronic bronchitis and asthma, may also increase the risk of stress incontinence.

Causes, incidence, and risk factors

The ability to hold urine and maintain continence is dependent on normal function of the lower urinary tract, the kidneys, and the nervous system. Additionally, the person must possess the physical and psychological ability to recognize and appropriately respond to the urge to urinate.

The process of urination involves two phases: 1) the filling and storage phase, and 2) the emptying phase. Normally during the filling and storage phase, the bladder begins to fill with urine from the kidneys.

The bladder stretches to accommodate the increasing amounts of urine. The first sensation of the need to urinate occurs when approximately 200 ml of urine is stored. The healthy nervous system will respond to this stretching sensation by alerting you to the need to urinate, while also allowing the bladder to continue to fill.

The average person can hold approximately 350 to 550 ml of urine. The ability to fill and store urine properly requires a functional sphincter muscle, controlling output of urine from the bladder, and a stable bladder wall muscle (the detrusor muscle).

The emptying phase requires the ability of the detrusor muscle to appropriately contract to force urine out of the bladder. Additionally, the body must also be able to simultaneously relax the sphincter to allow the urine to pass out of the body.

Symptoms
Loss of urine is a symptom that occurs when:

     
  • Coughing  
  • Sneezing  
  • Standing  
  • Exercising  
  • During other physical activity

Signs and tests

A physical examination will include an abdominal and rectal exam, a genital exam in men, and a pelvic exam in women. In some women, a pelvic examination may detect cystocele or urethrocele (protrusion of the bladder or urethra into the vaginal space).

Patients may be asked to keep a urinary diary, recording how many times you urinate during the day and night, and how often urinary leaking occurs.

Tests may include:

     
  • Post-void residual (PVR) to measure amount of urine left after urination  
  • Urinalysis or urine culture to rule out urinary tract infection  
  • Urinary stress test (the patient is asked to stand with a full bladder, and then cough)  
  • Pad test (after placement of a pre-weighed sanitary pad, the patient is asked to exercise - following exercise, the pad is re-weighed to determine the amount of urine loss)  
  • A pelvic or abdominal ultrasound  
  • X-rays with contrast dye of the kidneys and bladder  
  • Cystoscopy (inspection of the inside of the bladder)  
  • Urodynamic studies (tests to measure pressure and urine flow)  
  • Rarely, an EMG (electromyogram) is performed to study muscle activity in the urethra or pelvic floor

Other tests may include the measurement of the change in the angle of the urethra when at rest and when straining (Q-tip test). An angle change of greater than 30 degrees often indicates significant weakness of the muscles and tissues that support the bladder.

Treatment
The choice of a specific treatment will depend on the severity of the symptoms and the extent that the symptoms interfere with your lifestyle. There are four major categories of treatment for stress incontinence: behavioral changes, pelvic floor muscle training, medication, and surgery.

BEHAVIORAL CHANGES

Changing your fluid intake and voiding pattern may improve your stress incontinence symptoms. Your physician may recommend that you decrease your fluid intake if you drink an excessive amount of fluids during the day. (You should not decrease your fluid intake if you drink normal amounts of fluids.)

Urinating more frequently may help some patients decrease the amount of urine that they leak. Constipation can worsen urinary incontinence, so dietary or medical treatments to help keep regular bowel habits are recommended. Finally, weight loss has been shown to decrease stress incontinence in patients who are overweight.

Some people with severe stress incontinence may modify their activity level to avoid movements that cause greater leakage of urine. You may want to modify activities that involve jumping, running, and any activity that causes an increase in abdominal pressure.

PELVIC FLOOR MUSCLE THERAPY

Pelvic muscle training exercises (called Kegel exercises) may prove to be beneficial in controlling the leakage of urine that occurs in people with stress incontinence. The principle behind Kegel exercises is to strengthen the muscles of the pelvic floor, thereby improving the urethral sphincter function. The success of Kegel exercises depends on proper technique and adherence to a regular exercise program.

Some women may use vaginal cones to strengthen the ;elvic floor muscles. A vaginal cone is a weighted device that is inserted into the vagina. The woman should then try to contract the pelvic floor muscles in an effort to hold the device in place.

The contraction should be held for up to 15 minutes. This procedure should be performed twice daily. Within 4 to 6 weeks, about 70% of women have had some improvement in their symptoms.

If you are unable to correctly perform pelvic muscle exercises, biofeedback and electrical stimulation may be used to help identify the correct muscle group to work. Biofeedback is a method of positive reinforcement. Electrodes are placed on your abdomen and along the anal area.

Some therapists place a sensor in the vagina in women or anus in men to monitor contraction of the pelvic floor muscles. A monitor will show you which muscles are contracting and which are at rest.

The therapist can help you identify the correct muscles for performing Kegel exercises. Of the people who used biofeedback, about 75% have reported improvement of their symptoms, and 15% were cured.

Electrical stimulation therapy uses low-voltage electric current to stimulate and contract the correct group of muscles. The current is delivered using an anal or vaginal probe. The electrical stimulation therapy may be performed in the clinic or at home. Treatment sessions usually last 20 minutes and may be performed every 1 to 4 days.

A new technique using a specially designed chair with an electromagnetic field causes the pelvic floor muscles to contract while the patient sits in the chair. Other new devices are currently being tested that are placed into the vagina to provide correct bladder and urethral support or to help occlude the urethra. Ask your health care provider for more information about these devices.

MEDICATIONS

Medications used to treat stress incontinence are aimed at increasing the contraction of the urethral sphincter muscle. Treatment with medications tends to be more successful in patients with mild-to-moderate stress incontinence.

Alpha-adrenergic agonist drugs, such as phenylpropanolamine and pseudoephedrine (common components of over-the-counter cold medications) may be used to treat stress incontinence.

They work by increasing the strength of the urethral sphincter, and improve symptoms in about 50% of patients. Additionally, the tricyclic antidepressant imipramine has similar properties, and so it may also be used to treat stress incontinence.

Estrogen therapy can be used to improve symptoms of urinary frequency, urgency and burning in postmenopausal women, and it has also been shown to increase the tone and blood supply of the urethral sphincter muscles. However, whether estrogen treatment improves stress incontinence is controversial.

Estrogen may be taken by mouth, by a skin patch, or applied to the vaginal mucosa in a cream form. Women with a history of breast or uterine cancer should usually not use estrogen therapy for the treatment of stress urinary incontinence.

SURGERY

Surgical treatment is only recommended after thorough evaluation and determination of the exact cause of the urinary incontinence. The person considering surgery should be aware of the potential risks as well as the expected benefit of the procedure.

The goal of these surgical procedures is to cure the cause of the stress urinary incontinence either by supporting the bladder and urethra in its proper position, so it can function properly, or by tightening the urethral sphincter. The procedures are similar in men and women. However, the rationale for performing the procedure and the outcomes vary by gender.

COLLAGEN INJECTION

A minor surgical procedure called collagen periurethral injection may be recommended for treatment of male and female stress incontinence caused by urethral sphincter dysfunction.

This procedure is performed in an outpatient setting, with a local or spinal anesthesia. The procedure may need to be repeated after a few months to achieve bladder control. The collagen injection helps control the urine leakage by bulking up the area around the urethra, thus compressing the sphincter.

Women who were treated with collagen injection therapy reported a higher success rate (75% improved or cured) than men (52% improved or cured) who were treated with the same collagen therapy. Potential complications that can occur after a collagen injection include: infection, urine retention, and temporary erectile dysfunction in men.

Some people may have a potentially serious allergic reaction to collagen. Any potential candidate for collagen injection must have a skin test prior to treatment to check for an allergic reaction.

ANTERIOR VAGINAL REPAIR OR PARAVAGINAL REPAIR

These vaginal procedures are often performed in women when the bladder is prolapsing into the vagina (also called a cystocele). An anterior vaginal repair is performed through a vaginal incision, and a paravaginal repair is performed through either a vaginal or an abdominal incision.

In an anterior repair, the pubocervical fascia (the supportive tissue between the vagina and bladder) is folded and stitched together to bring the bladder and urethra in proper position. In a paravaginal repair, the pubocervical fascia is stitched to the fascia covering the pelvic floor muscles to support the bladder and urethra.

Studies have shown that the cure rate for stress urinary incontinence from these procedures is only about 40-65%, and because other surgeries are more effective, these are usually performed to repair a cystocele, but not for stress urinary incontinence. Often, these procedures are performed along with another procedure for stress incontinence, such as a retropubic suspension.

NEEDLE BLADDER NECK SUSPENSION

There are several surgical procedures that are performed in women through a minor abdominal incision as well as a vaginal incision to repair the bladder and urethral dysfunction.

These procedures are called needle procedures because special needle instruments are utilized during the surgery, which requires only a small abdominal incision. The various procedures (Modified Pereyra and Stamey procedure) differ based on the structures that are used to anchor and support the bladder.

Women treated with these procedures have a 40-80% cure rate. Because the success rate tends to be lower than that achieved with retropubic suspensions or sling procedures, these procedures are being performed less often than in the past. Possible complications include urinary tract infection, inability to urinate, wound infection, fistula (rarely), and new onset of urge incontinence.

RETROPUBIC SUSPENSION

Retropubic suspension is used to describe a group of surgical procedures performed to elevate the bladder and urethra within the pelvic region. These procedures are performed through an abdominal incision. The procedures (Burch colposuspension and Marshall-Marchetti-Krantz - MMK) differ based on the structures that are used to anchor and support the bladder.

Women treated with these procedures have a 75-90% cure rate. Possible complications include urinary tract infection, inability to urinate, wound infection, fistula (rarely), and new onset of urge incontinence.

SLING PROCEDURE

This procedure is rarely performed in men, but is more often used to treat women who have stress incontinence caused by weakened urethral sphincter muscles. A sling is formed by taking a piece of the abdominal tissue (fascia) or a piece of synthetic material and using it to compress the urethral sphincter, thus preventing leakage of urine during stress maneuvers.

These procedures require a small abdominal incision and a vaginal incision. Many modifications of the sling procedure have been developed, including recently the transvaginal tape procedure. This type of sling procedure is performed through smaller incisions and can be done as an outpatient surgery.

Among the people who have had sling procedures to correct their stress incontinence, there is an 80-90% cure rate. Possible complications include infection, erosion of the sling, non-healing vaginal wall, fistula or abscess formation, urgency, urge incontinence, and urinary retention.

ARTIFICIAL URINARY SPHINCTER

This is a surgical procedure to treat stress incontinence in men, which most commonly occurs after prostate surgery. Artificial urinary sphincters are rarely used in women. Most experts advise their patients to try other treatments first, before resorting to this treatment.

Men who were treated with this device had an 82% cure rate, while women had a 92% cure rate. Possible complications of this surgery include wound infection and urethral erosion, requiring removal of the device.

Additionally, because the pump mechanism is placed in the labia in women, and the scrotum for men, the patient may need to modify some activities (such as bicycle riding) to accommodate the pump.

MONITORING

Urinary incontinence is a chronic (long-term) problem. Although some people may be cured by various treatments, you should continue to see your health care provider to evaluate the progress of your symptoms and monitor for possible complications of treatment.

Expectations (prognosis)

Behavioral changes, pelvic floor exercise therapy, and medical management of stress incontinence usually improves symptoms rather than cures the disorder. Surgery may have a 75% to 95% cure rate when patients are carefully selected.

A poorer outcome is expected in people with previous surgical failures, other genital or urinary problems, or with systemic conditions that may prevent adequate healing or make the technical aspects of the surgery more difficult.

Complications
Physical complications (such as vaginal discharge, vulvar irritation, and pain during intercourse) are relatively rare and mild. Unpleasant odors may occur. The psychosocial implications of incontinence may be significant because the condition may affect or disrupt social activities, careers, and relationships.

Calling your health care provider

Call for an appointment with your health care provider if symptoms of stress incontinence occur and are bothersome.

Prevention

Performing Kegel exercises (tightening muscles of the pelvic floor as if trying to stop urine stream) may help prevent the development of symptoms. Performing Kegel exercises during and after pregnancy can decrease the risk of developing stress urinary incontinence after childbirth.

Johns Hopkins patient information

Last revised: December 3, 2012
by Levon Ter-Markosyan, D.M.D.

Medical Encyclopedia

  A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | 0-9

All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.