Stress Urinary Incontinence

Overview

Stress Urinary Incontinence (SUI) is an uncontrollable, involuntary leaking of urine that occurs when abdominal pressure or "stress" is placed on a weakened urethral sphincter muscle (the bladder "valve" outlet).

Every-day occurrences, such as coughing, sneezing, exercise, laughing, or lifting can place "stress" on the bladder and may trigger an SUI episode. SUI differs markedly from other types of incontinence, including overactive bladder (OAB), and it is the most prevalent form of the problem.

SUI is distinctive from Overactive Bladder (OAB):

  • SUI is not accompanied by the urge to urinate (OAB is urge and frequency).
  • The underlying cause for SUI is different than for OAB.
  • SUI often begins affecting women in the prime of their lives.

90% of those suffering from SUI are women.

Normal Vs. Abnormal Bladder Function

With respect to stress incontinence, there are three common factors associated with maintaining continence:

  • Urethral closure pressure
  • Pressure transmission
  • Intra-abdominal pressure

Bladder pressure

 

In women with SUI, laughing, coughing, sneezing, or physical activity places increased pressure on the bladder and may cause urine leakage. SUI occurs when either the pelvic floor muscles or the urethral sphincter muscle become weak. As a result, the base of the bladder may move from its normal position, or the bladder's closing mechanism, the urethra, may close insufficiently.

When either of these conditions occurs, the urethra is unable to withstand sudden increases in abdominal pressure, or stress, upon the bladder, resulting in urine leakage.

SUI is a result of weakened or damaged pelvic muscles, bladder valve, and/or pelvic nerve supply. When bladder pressure exceeds the strength of the urethral sphincter muscle, leakage occurs.

Specifically, there are two diagnostic categories associated with SUI: intrinsic sphincteric deficiency (ISD) and urethral hypermobility. 

ISD refers to the inability to effectively seal off the sphincter, the ring of muscles that is normally tightened to keep urine in the bladder. 

The urethra is the tube connected to the bladder from which urine exits the body. In the case of urethral hypermobility, the urethra shifts positions with an increase in abdominal pressure, allowing urine to exit the bladder.

Since so may women suffer with SUI, treatment options for this condition have evolved to be increasingly refined and targeted to treat both diagnostic categories of SUI.  

 

The Myths and the Reality

Myths prevent women from getting help, causing them to feel alone. There is a mistaken belief that SUI:

  • Comes from aging
  • Is part of being a woman
  • Is caused by sexual activity
  • Results from drinking too much water

Overcoming the taboo about SUI requires addressing several misconceptions and facts, including the following:

  • SUI is a legitimate medical condition, but eight out of 10 women mistakenly believe that it is a normal part of aging. On the contrary, women in the prime of life suffer from SUI. Research published by the World Health Organization (WHO) confirms that SUI affects 35 to 60 year old women.
  • Only one out of 12 women seeks help for her condition, choosing instead to cope for several years before discussing the disease with her doctor.
  • Sufferers say the condition is embarrassing, socially isolating and debilitating.

Causes

The following can be risk or contributing factors for stress urinary incontinence:

  • Pregnancy and childbirth
  • General loss of pelvic muscle tone (often with aging)
  • Hysterectomy
  • Nerve and muscle damage as result of (birth) injury or surgery
  • Obesity - Diabetes
  • Menopause
  • Smoking and Lung Disease
  • Chronic Coughing
  • Constipation
  • Anatomical Predisposition
  • Job related - Heavy lifting: high impact  

Prevalence

  • It is estimated that one in four women over the age of 18 in the U.S. have experienced an episode of SUI. (1)
  • SUI is a woman's condition with 90% of sufferers being female.
  • SUI is an uncontrollable and involuntary loss of urine that occurs when abdominal pressure or "stress" is placed on a weakened urethral sphincter muscle (the bladder "valve" outlet).
  • Every day occurrences, like coughing, sneezing, exercise and laughing, can place "stress" on the bladder and may trigger a SUI episode. (2)
  • SUI often begins affecting women in the prime of their lives. (3)
  • Common inciting causes of SUI, which may lead to a weakened urethral sphincter muscle, childbirth trauma, nerve and muscle damage, pelvic and abdominal surgery, and general loss of pelvic muscle tone. (4)
  • Other factors that may promote the onset of SUI include obesity, constipation, and childbirth. (5) In certain cases, some women may have a neurological, anatomic or muscular predisposition to develop SUI. (6)
  • In 1998, the World Health Organization described incontinence as a widespread global disease and one of the last real medical taboos for many people. (7)

  • The Society for Women's Health Research conducted a study quantifying the significant added medical costs for women treated for SUI in the United States. The findings showed that the incremental, lifetime medical cost of treating a woman with SUI is $58,000, compared to treating a woman without the condition. (8)

SUI Underdiagnosed and Overlooked SUI often goes undiagnosed because many women are too embarrassed to discuss it with their doctors. (9) Low awareness of the condition among the medical community and the absence of a drug treatment make SUI a low priority for physicians.

Prevalence References

1.) NAFC survey conducted by Harris Interactive, 2002

2.) Voelker, R. International Group Seeks to Dispel Incontinence "Taboo", JAMA, 1998, Vol. 280, No.11: 951-953

3.) ibid

4.) Bump, R., Norton, P., Epidemiology of Natural History of Pelvic Floor Dysfunction, Obstetrics and Gynecology Clinics of North America, 1998, 5 Vol.25, No.4

5.) ibid

6.) ibid

7.) Voelker, R. International Group Seeks to Dispel Incontinence "Taboo", JAMA, 1998, Vol. 280, No.11: 951-953 8.Society for Women's Health Research Survey 2002. Lifetime Medical Costs for Women. Study conducted by Analysis Group/Economics. Qualitative Research Amongst Stress Incontinence Sufferers, Complete Market Research Ltd., 2000

Impact

Many Women Cope Without Help

  • Majority of women tolerate their symptoms for years - and do not seek treatment
  • Average wait before seeking help: 3-10 years
  • Women buy more sanitary pads for incontinence than for menstruation

Women Reorganize Daily Lives

  • Wear protective products
  • Reduce fluid intake
  • Change activities: Give up "active" work,switch from high -> low - impact exercise, limit lifting children, groceries
  • Give up travel

Psychosocial Impact

Women struggle with many issues Loss of self-confidence, self-esteem, sexuality

  • Self-consciousness about being discovered
  • Embarrassment and the fear of odor
  • Secrecy
  • Loss of productivity - financial concerns

Frustration and sense of defeat

  • Loss of control over body
  • Limited treatment options - don't want surgery
  • Failed previous treatments
  • Treatment with OAB medications ineffective

Emotional Insight

  • SUI causes sufferers to feel different
  • They say... I'm no longer myself I feel trapped I am the only one I'm losing control I no longer do the things I love

SUI Emotional Impact

  • In women past the age of 40, SUI can have significant impact on their lives - many SUI sufferers report the condition to be embarrassing, socially isolating and debilitating. (1)
  • Some of these women wear sanitary napkins or wads of tissues in their panties and are too embarrassed to talk to their doctors. SUI can diminish women's ability to cope with daily life activities (domestic chores, exercise, etc.), and can have a negative effect on their social lives as they feel obliged to wear unattractive clothes and restrict their activity for fear of the odor. (2)
  • Emotionally, women can experience a general lack of self-confidence and shame. (3)
  • Women may also experience reduced intimacy in their personal relationships.

Impact References

1.) Qualitative Research Amongst Stress Incontinence Sufferers, Complete Market Research Ltd., 2000

2.) ibid

3.) Thor KB, Katofiasc, MA, Effects of Duloxetine, a combined serotonin and norepinephrine reuptake inhibitor, on central neural control of lower urinary tract function in the chloralose anesthetized female cat, J Pharmacol Exp Ther, 1995; 274: 1014-1024

Treatment

SUI presents an unmet medical need: behavioral approaches often fail, there are currently no approved drugs to treat the condition, and surgery is often a patient's last resort. Following are existing alternatives for SUI treatment:

 

Behavioral Intervention

Physicians generally pursue non-invasive therapeutic interventions before attempting to treat SUI with surgery. Such interventions include:

  • Kegel exercises: exercises designed to help women with SUI strengthen weak pelvic muscles around the bladder. Often the first line of treatment, Kegel exercises strengthen the pelvic floor muscles and assist in toning the bladder valve muscle. These are, however, difficult to perform and, because most women do not take the time necessary to ensure their success, the compliance rate is low.
  • Changing fluid intake: for some people, increasing or reducing fluid intake or changing the timing of fluid intake allows them to increase bladder control.
  • Timed Voiding: emptying at intervals of 2-3 hours to avoid over-filling.
  • Biofeedback: electronic devices or diaries to help patients track, and ultimately control, incontinence when the bladder and urethral muscles contract. Often used in concert with Kegel exercises and electrical stimulation
  • Electrical stimulation: electricity can stimulate contraction of the muscles in the lower pelvis, which reduces the symptoms of SUI

Medications

Though millions of people suffer from SUI, there are no FDA approved pharmaceutical medications to treat the condition. Duloxetine is the only medication used to treat SUI, but it is not FDA approved for that indication in the United States. The same active ingredient is approved for treating depression in the United States.

 

While duloxetine is not available for the treatment of SUI in the US, it is approved and marketed for this condition in numerous other countries outside the US, sold under the brand names Yentreve® or AriClaim®. It is thought to increase the tone and contraction of the urethral sphincter, therefore preventing leakage associated with a deficient sphincter.

 

Evidence indicates that SUI symptoms are caused, in part, by a weakening of the urethral sphincter, a problem that can be corrected by stimulating central nervous system processes, particular by signal transmission, with pharmacological agents. Duloxetine serves as an inhibitor of certain common neurotransmitters, ie. serotonin and norepinephrine.* They are believed to play key roles in the normal closure of the urethral sphincter, weakening of which can contribute to the development of SUI. Thus, duloxetine helps helps to prevent leakage by improving the tone and ability of the urethral sphincter to contract as it should to close at the bladder neck's opening.

 

*Bymaster FP, Dreshfield- Ahmad LJ, Threlkeld PG et al. Comparative affinity of duloxetine and venlafaxine for serotonin and norepinephrine transporters in vitro and in vivo human serotonin receptor subtypes, and other neuronal receptors. Neuropsycho- pharmacol 2001; 25(6): 871-80.

 

Minimally Invasive Procedures

  1. Implants, sometimes called "bulking agents", can be injected into the tissues around the urethra to add enough bulk to close the urethra and reduce stress incontinence. Collagen (fibrous natural tissue from cows) and fat from the patient's body have been used for implants. The procedure has only a partial success rate, and injections must be repeated after a time because the body slowly eliminates the substances. Another bulking agent is composed of pyrolytic carbon-coated beads suspended in a water-based carrier gel. It is injected under the mucosal lining of the bladder neck and urethra to expand and close the bladder neck and is designed to be non-migratory, non-absorbable, and biocompatible. While Collagen has historically been used as an injectable, there are newer injectables that are synthetic. All bulking agents are indicated for the treatment of SUI due to intrinsic sphincteric deficiency.

  2. There is also a non-surgical approach to treat SUI due to bladder outlet hypermobility: the Renessa® System. This procedure uses radiofrequency energy (RF) to generate controlled heat at low temperatures in tissue targets within the lower urinary tract. The heat breaks down collagen in the tissue at multiple small treatment sites. Upon healing, the treated tissue is firmer, increasing resistance to involuntary leakage at times of heightened abdominal pressure, such as when laughing, sneezing, or lifting something heavy. This treatment uses a small probe which a physician passes through the urethra. It can be performed in a physician's office or other outpatient setting. There are no incisions, bandages or dressings required. Recovery is reported to be rapid, with minimal post-procedure limitations.

    *Renessa is not to be confused with radio frequency bladder neck suspension, listed under the "Surgical Intervention" section below.

Surgical Intervention

Surgical intervention may be appropriate for some women.

  1. Sling procedures, which are meant to support the urethra in times of increased abdominal pressure, are now a common means of surgically treating SUI. There are variety of materials used, ranging from human and animal tissue to synthetic materials. There are also various routes used to deliver the sling material into position. For example, tension-free procedures using an implantable mesh offer a viable option for the successful treatment of SUI with less invasive surgery. The technique is less complex than other surgical options, offering the potential for a quick recovery and return to normal activity. It primarily consists of a mesh-like tape that is surgically inserted through the vagina to support the bladder neck and urethra. No sutures or anchors are necessary as they are with other procedures because the mesh-like tape will not stretch significantly. This procedure should not be used in women who plan future pregnancy.
  2. In some cases, surgery to lift the bladder and/or urethra back to the correct alignment will prevent the loss of urine as a result of laughing, coughing or sneezing. The invasive procedure can be performed through abdominal surgery or transvaginally.

 *With any surgical procedure, be sure to ask your doctor what is best for you. Also be sure to make sure that your doctor has experience in performing the surgery that he or she recommends. 

 

Conclusion

While their are many sufferers of stress incontinence, individuals should feel encouraged to get a diagnosis and seek treatment for this treatable condition.

 
    
Updated: Mar.27.2008