This chapter should be cited as follows:
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Authors

INTRODUCTION

Surgery has long been considered the mainstay of treatment for urinary stress incontinence in women. However, nonsurgical treatment can improve symptoms for many patients and should be presented as an option before surgical treatment is considered. Although fewer women treated nonsurgically are completely cured of their incontinence compared with those who undergo operative therapy, the tradeoffs of decreased risk and morbidity result in a high satisfaction rate for many women.  Researchers are exploring various forms of nonsurgical treatment, and in the future, clinicians will probably have more information about which modalities to use for specific individuals.

LIFESTYLE INTERVENTIONS

Obesity and Diet 

Several lifestyle interventions are frequently recommended to prevent or treat stress incontinence. However, there is limited scientific evidence to guide recommendations for any of these interventions. It is clear that obesity is a risk factor for stress incontinenceand that weight loss in morbidly obese women alleviates stress incontinence.1, 2, 3  The mechanism is thought to be due to increased intra-abdominal and intravesicular pressure from increased abdominal weight. Evidence also suggests that weight loss reduces urinary stress incontinence in moderately obese women.4,  A cohort of 10 women with a mean body mass index (BMI) of 38.3 and mean weight of 106 kg decreased the overall mean number of incontinence episodes from 13 to 8 per week. All six of the women who lost at least 5% of their weight decreased the number of incontinence episodes by at least 50%, compared with only one of the four women who lost lesser amounts of weight. In a larger randomized trial, 40 women with stress incontinence were randomized to either an immediate weight loss program with a liquid diet for 3 months or a wait-list delayed intervention starting 3 months later.5,  The average weight was 97 kg and the mean rate of stress incontinence was 21 episodes per week. The immediate intervention group experienced a 60% reduction in weekly incontinent episodes compared to 15% in the delayed treatment group at 3 months. Quality of life scores were also higher for the immediate intervention group. Weight loss of 5–10% had an efficacy similar to that of other nonsurgical treatments. Incontinence and quality of life outcomes were maintained for 6 months following weight loss. In overweight patients, reduction in weight may be a reasonable first line of therapy which may also reduce other comorbidities associated with obesity.  

One study from the United Kingdom found a significant reduction in urine loss measured by pad test and an increase in quality of life for women achieving at least 5% body weight reduction through diet and exercise and if needed, the use of anti-obesity medications.3  On urodynamics, 40% of women diagnosed with stress incontinence had resolution based on repeat testing after weight loss.

 

 

Diabetes 

Recent studies have identified diabetes mellitus as a risk factor for stress incontinence. The Kaiser Permanente Continence Associated Risk Epidemiology Study found that of the women who had diabetes, 15% had urinary stress incontinence and women with diabetes were 90% more likely to have stress incontinence or overactive bladder.6  Data from the National Health and Nutrition Examination Survey(NHANES) was used to identify the prevalence and risk factors for urinary stress incontinence in women with diabetes or impaired fasting glucose, defined as a level between 100 and 125mg/dL.7  Of 1,461 women, 246 (16.8%) were classified as diabetic and 164 (11.2%) were defined as having impaired fasting glucose. Stress and urge incontinence were significantly more common among diabetic and prediabetic patients with an estimated 2-fold increase in prevalence of stress incontinence compared to non-diabetic patients. Women with diabetes also considered their incontinence more bothersome compared to non-diabetic incontinent patients.  These investigators also found that patients with macroalbuminuria and peripheral neuropathies had an increased risk of weekly incontinence episodes, possibly suggesting incontinence may be a microvascular complication. Diabetic and pre-diabetic women taking oral estrogen were also found to have a 3-fold greater risk for incontinence, compared to those off oral hormone replacement therapy.

Another epidemiological study from Norway found the prevalence of incontinence among diabetic women to be 39% compared to 29% in non-diabetic women.8  Stress incontinence was the most prevalent type of incontinence in non-diabetic women, whereas mixed urinary stress incontinence was the most prevalent in diabetic women.   

Gestational diabetes may also predispose some women to develop urinary stress incontinence.  In a cross-sectional study of 228 women with gestational diabetes, urinary stress incontinence was found in approximately 50% of women, and 28% reported interference with activities during and after pregnancy due to incontinence.9  Interestingly, no association with stress incontinence and levels of physical activity or body mass index was identified.

 

 

Smoking

 

 

Some studies have found an association between cigarette smoking and urinary stress incontinence, but it is unclear whether smoking cessation decreases urine leakage.10  A recent, randomized study reported that smokers had 56% more episodes of incontinence when compared to non-smokers.11  In a longitudinal study with 6,424 women over 40 years of age, current smokers were at a higher risk for both stress and urgency incontinence compared to those who had never smoked.12  Intermediate risk was identified for those who were ex-smokers. Smoking, however, was not a significant risk factor for stress incontinence, but was for overactive bladder.  Conversely, in another large population-based survey, analysis showed that neither former nor current smoking increased the risk for any incontinence when compared to having never smoked.13,  While there are conflicting studies, it would be advisable to recommend smoking cessation to reduce the other known health risks associated with cigarette smoking.

 

 

Caffeine and Fluid Intake 

A small number of studies have assessed the efficacy of caffeine restriction, fluid management, or dietary changes in the treatment of incontinence. In a cohort study in which 41 women worked with a nurse during home visits to reduce incontinence, women were advised to decrease caffeine and increase other fluid intake.14  There was a trend between the decrease in caffeine and fewer daytime incontinence episodes.  In a subsequent randomized trial, adults that received education by continence advisors about reducing caffeine intake did so, and they also noticed improved urgency and frequency.15  It may be helpful to advise women who report a high caffeine intake (more than 6 cups per day) to initially taper down to 1 to 2 cups per day. Gradually making this change over 3–4 weeks will help to minimize the caffeine withdrawal headaches experienced by many patients.

For individual patients, a voiding diary may provide important clues for managing women with incontinence. By reviewing this 3- to 7-day record of the patient's intake and output, the patient and clinician can discuss whether decreasing the fluid intake or increasing the voiding interval is appropriate. Although there is no role for decreasing fluid intake in women with normal urinary output, women who drink excessive volumes of liquid can benefit by restructuring their intake. Restricting fluids often results in fewer nocturnal voids and may be particularly helpful to those with restricted mobility. Certain professions are associated with more infrequent voiding than professions with easier bathroom access. When a woman becomes aware of the connection between her daily stress incontinence and a concomitant very full bladder, she usually finds the time to void at least once in the middle of the working day.  In a recent randomized, prospective observational study, 39 women with stress incontinence kept voiding diaries over a 4-week period.16  The first week was at baseline, followed by caffeine restriction for the next 3 weeks.  During week 2, the women drank normally, and during weeks 3 and 4 the women increased (3 liters daily) or decreased the amount of decaffeinated fluids (750 ml daily).  They found the number of wetting episodes during the baseline week to be significantly greater when compared to the week of decreased decaffeinated fluids.  No significant difference was observed between caffeine restrictions with the same fluid intake.  There were more statistically significant wetting episodes during the week of increased fluid intake.

 

 

Bowel Habits 

Defecation disorders are often observed in women with urinary stress incontinence.  One studyfound that 30% of women with stress incontinence reported straining at stool as a young adult compared with 4% of women without urogynecologic symptoms.17  Another study found that women undergoing urodynamics for lower urinary tract dysfunction are significantly more likely to have symptoms of obstructive defecation when compared to similar controls.18,  A specific association, however, between stress incontinence was not confirmed.  While no rigorous research has assessed whether treating constipation affects incontinence, anecdotal evidence suggests that it does in certain instances.   

PELVIC FLOOR MUSCLE TRAINING

Pelvic floor muscle exercises have been one of the traditional nonoperative treatments used for management of female urinary stress incontinence. First described by Kegel in 1948, the exercises are designed to strengthen the musculature of the pelvic floor to provide better support for the bladder and urethra.19  Kegel described concomitant use of a pneumatic device, the perineometer, to measure the strength of the pelvic contractions during the exercises. This was essentially an early type of biofeedback therapy. The term pelvic floor muscle training (PFMT) is the current term used for pelvic floor rehabilitation and is defined as a program of voluntary repeated pelvic floor muscle contractions.  It is typically recommended that they be taught by a health care professional.

Although the exercises are designed to improve muscle strength of the pelvic floor, the exact physiologic basis for symptom improvement is not completely understood. A recent study of pelvic floor electromyography (EMG) revealed that women with stress incontinence have impairment in vaginal EMG compared with continent controls.20   In this study, 60 women with incontinence were compared to 28 healthy control subjects. Fifty of the incontinent women completed the study and were evaluated. Overall, the vaginal EMG function improved successively over the 4-month treatment period for the incontinent patients. This was associated with improvement in clinical symptoms. This supports the contention that pelvic floor muscle exercises help to strengthen muscular function.

Despite widespread advocacy for pelvic floor muscle exercises in the medical literature and the lay press, success rates reported in clinical trials have varied widely. A number of different clinical parameters have been examined to assess their influence on the ultimate success rates for pelvic floor muscle exercise programs. A recent Cochrane Review included six randomized trials with 403 patients comparing pelvic floor muscle training to no treatment.21  Two of the six trials reported data related to “cure” and found in both that women reported a statistically significant improvement with PFMT. A secondary outcome was the number of leakage episodes in a 24-hour period. In this systematic review, it was found that PFMT patients had one less leakage episode per 24 hours compared to the placebo or sham group. Four studies used perineometry, one used digital palpation, and the sixth used electromyography (EMG) to assess function of the pelvic floor muscles. Of the trials using perineometry, two identified a statistically significant difference in pelvic floor muscle squeeze pressure, while in the two other studies it was reported that there was no significant difference.  One analysis which utilized electromyography to assess fast and sustained contractions found no significant difference between groups.

Training women how to perform pelvic floor exercises may also improve continence outcomes after pregnancy and delivery.  In a trial of 268 primigravid women, Reilly and colleagues randomized women to monthly physiotherapy appointments beginning at 20 weeks' gestation until delivery versus control.22
The control subjects received verbal instruction in pelvic floor exercise, but no physiotherapy sessions. They found that fewer women in the formal physiotherapy group reported postpartum incontinence (19.2% compared with 32.7%; RR: 0.59; 95% CI: 0.37–0.92). They concluded that antenatal pelvic floor muscle exercise improved outcomes, although it did not necessarily improve pelvic floor strength. While only 37% (100/268) of patients were available for follow-up, the effects were still observed 4 years post-partum. Similar results were demonstrated by Mørkved et al. in a long-term follow-up study of patients who had undergone an 8 week training course post-partum.23  At 1 year, fewer women in the training group reported stress incontinence. They also found a significantly greater muscle strength increase from the 16th week post-partum to 1 year in the training group (mean 4.4 cmH2O; 95% CI: 3.2–5.6) compared to the control group (mean 1.7 cmH2O; 95% CI: 0.8–2.7).  Motivation and proper technique on the part of the clinician teaching the exercises and by the patient herself may affect outcomes. The patient must be able to perform the exercises correctly for them to be expected to work. Kegel himself reported that 30% of women could not correctly contract their pelvic floor muscles on the first attempt.24  Zahariou et al. examined the effectiveness of pelvic floor muscle exercise by measuring urethral closure pressure at baseline and again at 12 months in 50 patients.25  They also studied the pressure transmission ratio, and identified a significant increase in the mean measurement. However, there was no significant change in the urethral closure pressure.

Most clinicians advocate teaching pelvic floor muscle exercises during pelvic examination or urodynamic assessment, when more directed instruction can be provided. This also permits the clinician to determine if the exercises are being performed correctly from an anatomic perspective. Despite intensive therapy, it is still possible that women may not be able to correctly contract the pelvic floor muscles.  In a recent randomized, controlled trial, Sampselle and her colleagues found 3% of women were unable to learn proper pelvic floor muscle contraction techniques.26

After patients learn how to perform the exercises correctly, compliance becomes an important issue. Intuitively, repeated training sessions or other types of motivational or educational reinforcements would be thought to increase the likelihood of success. In the 2008 Cochrane Review, five trials examined treatment adherence using self-report and diaries.21  The reported rates of compliance with PFMT ranged from 15 to 95%.  In a separate study examining long-term compliance, Bø et al. found a 60% initial response rate to intensive PFMT in a cohort of women.  However, followup at 15 years showed an extremely low rate of adherence to the exercises.27  Kondo et al. recently reported an 8-year follow-up for 79 out of 123 women who had previously participated in an 8-week PFMT program. They found a 39% success rate at 8 years.28

A recent prospective randomized study compared the results of pelvic floor muscle exercises with or without physiotherapist supervision.29  Twenty-three patients worked with a physiotherapist three times a week for 45 minutes, whereas 21 patients making up the control group performed exercises at home, unsupervised, but did meet monthly with a physiotherapist. The same exercises were taught to both groups and they were followed for 12 weeks. A significant improvement in the quality of life was observed from baseline to the end of the 3 months in patients who were supervised compared to the control group. Objectively, there was a significant decrease in the weight of pads for both groups, but the supervised group had a greater overall reduction than the control group. Sixty-six percent of patients in the supervised group did not want any other treatment while in the unsupervised group, compared to 23% in the unsupervised group.

Other studies that have examined the effectiveness of adjunctive training methods designed to reinforce the initial education have yielded conflicting results. Sugaya et al. performed a study comparing the efficacy of an electronic device used at home to prompt when a patient should perform exercises.30  Patients were randomized either to a group that performed exercises for two minutes every time the device sounded (three times daily),  or the control group that was instructed to perform the same amount of exercises daily without the electronic prompt.  In the group with the prompts from the device, the number of incontinence episodes and the number of pads used improved significantly, as did the measurement of quality of life. The control group only had an improvement in the quality of life questionnaire. Forty-eight percent of patients in the device group and 15% in the control group were satisfied with the outcome.

A cross-sectional study of 129 women who were prescribed pelvic floor muscle exercise as a treatment for incontinence identified several predictors of continued compliance.31  Subjects were asked to complete a questionnaire that was developed based on behavioral theories, focus group interviews, and published literature regarding adherence to treatment regimens. A regression analysis of the data revealed that the amount of urinary loss per episode and an individual patient's perception of her ability to perform the exercises were the most important predicators of continued exercise.

The overall reported efficacy of pelvic floor muscle exercises is highly variable.  A 2002 Cochrane database analysis of 43 clinical trials yielded divergent results.32  Most of the trials were quite small, and many had limited follow-up. Patient discontinuation of therapy was also variable. Loss to follow-up ranged from none (reported in ten trials) or less than 10% (in seven trials) up to a maximum of 41% in some studies. Overall, these authors concluded that, based on the available literature reviewed, pelvic floor exercises were better than placebo or no therapy for women with stress or mixed incontinence. They also found that intensive forms of training tended to yield better overall results than standard training techniques. The data were too limited to permit conclusions about the effect of combining pelvic floor muscle exercises with other forms of therapy. They concluded that large, high-quality, randomized trials were necessary to determine the overall efficacy of pelvic floor exercise in women with urinary stress incontinence.  More recently, a meta-analysis of 6 clinical trials found pelvic floor muscle training to be better than no treatment or placebo. These particular studies also suggested a greater treatment effect in younger women, supervised treatment, and treatment of greater than 3 months' duration.21   Again, the need for larger, multi-center, randomized studies was emphasized.

Estrogen replacement has been tested in combination with pelvic floor muscle exercise.  Ishiko and colleagues randomized 66 women to pelvic floor exercises alone or in combination with estrogen replacement using estriol 1 mg/day.33   They demonstrated improvement in both groups, although the treatment effect was more pronounced for the group that also received hormone replacement. The effect was sustained for 18 months in subjects with mild incontinence and 12 months for those with moderate incontinence. However, the findings are limited by the short duration of follow-up and small patient numbers.

A variety of other techniques and devices have been devised to supplement pelvic floor muscle training exercises, including weighted vaginal cones, biofeedback therapy training, and electrical stimulation. Each of these treatment adjuncts will be considered separately.

ADJUNCTIVE THERAPIES

Vaginal Cones 

 

The idea of using weighted vaginal cones to test pelvic floor muscle contraction strength and augment exercises was first introduced by Plevnik in 1985.34   The original description included a set of nine cones that ranged from 20 to 100 grams. The cones are placed intravaginally, with the tapered end directed toward the introitus. The patient attempts to retain the cones in the vagina when she is up and active. Theoretically, the weighted cone acts to provide a constant stimulus for proprioceptive feedback. The patient is instructed to actively contract her pelvic floor muscles when she feels the cone slipping out of the vagina. This provides a form of biofeedback in an attempt to improve pelvic floor muscle exercise efficacy. 

 

Few randomized trials of cone therapy have been reported.  Bø et al. performed a randomized, single-blind study comparing the use of vaginal cones with electrical stimulation to that of PFMT.35  Adherence to PFMT was greater than that for the vaginal cones (93% vs. 78%, respectively). The change in  pelvic floor muscle strength was significantly greater in the PFMT group compared to the vaginal cone and electrical stimulation group. Twenty-three out of the 27 women assigned to the vaginal cone group wanted additional treatment with a different method than they were assigned originally.  

 

Cammu and Vannylen randomized 30 patients to cone therapy and 30 patients to pelvic floor muscle exercises without cones.36  However, 47% of the patients in the cone group discontinued treatment before the completion of the 12-week treatment program.  All of the remaining patients in the cone group chose to discontinue therapy at the end of the 12 weeks.  The investigators compared outcomes in three groups: those who completed cone therapy, those who discontinued cone therapy, and those who completed the exercise program without cones. There was no statistically significant difference in continence outcomes identified between any of the groups. These investigators concluded that the high discontinuation rate and lack of significant improvement compared with standard pelvic floor muscle exercise programs does not justify the use of weighted vaginal cones. A more recent study randomized women to pelvic floor exercises alone or in combination with either vaginal cones or pressure biofeedback.37  These authors found that patients in all three treatment groups demonstrated improvement in urinary stress incontinence symptoms. However, there was no significant difference between the groups.  In a recently published randomized, controlled trial comparing PFMT, vaginal cones, and electrical stimulation to placebo, Castro et al. found all forms of therapy to be equally effective with 54–58% subjective success.38  Arvonen et al. conducted a prospective, randomized trial comparing the use of vaginal balls in combination with pelvic floor muscle training.39  The study population was small, but they found a significant decrease in urinary leakage and an increase in pelvic floor muscle strength for both groups. The group using the vaginal balls was found to have a greater reduction in urinary leakage when compared to the control group. 

 

A recent meta-analysis examined the use of vaginal cones.40  This review of 17 studies included a total of 1,484 patients, 646 of whom received vaginal cones. The data revealed that cones were better than no active treatment (failure to cure incontinence RR = 0.88; 95% CI: 0.79–0.98), but little difference between cones and pelvic floor muscle training (RR = 1.00; 95% CI: 0.91–1.11) or electrostimulation (RR = 1.00; 95% CI: 0.8–1.13).  Many of these small published studies on the use of vaginal cones have methodological flaws that prevent adequate comparative interpretation for measured outcomes. In particular, the paucity of randomized trials and the relatively high discontinuation rate of patients treated with vaginal cones make this a less appealing treatment option. Well-designed randomized studies are needed to answer some of the fundamental questions about the ultimate utility of vaginal cones in the treatment of female urinary stress incontinence. In particular, there is a specific need for good long-term data on the efficacy of vaginal cone therapy. The data available to date suggest that the primary benefit of cones may be to help motivate or remind patients to continue to perform pelvic floor exercises.  

 

Biofeedback 

 

Biofeedback therapy uses monitoring devices that provide visual or auditory cues to the patient during pelvic floor muscle exercises. This helps to indicate that the patient is contracting the correct muscle and provides a measure of the strength of contractions. The concept of biofeedback is based on the belief that the added stimulus of the feedback information helps improve motor skill development.41   Most programs involve multiple formal training sessions with the patient using the device during each session to monitor progress. The devices typically use urethral, vaginal, or rectal probes that are connected to monitors to provide information directly back to the patient. 

 

Studies comparing pelvic floor muscle exercise training with and without the biofeedback component have yielded mixed results.  A randomized, controlled trial of 40 women was conducted by Pages et al.42  They conducted a 4-week trial consisting of biofeedback and physical therapy followed by 2 months of home exercises. After 3 months, 62% of patients in the biofeedback group reported being free of incontinent episodes and 38% reported improvement. The biofeedback group also had a statistically significant improvement in strength assessments, speculum tests, and manometric measurements. In the physical therapy group, 28% of patients were free of incontinence episodes and 68% reported improvement with 4% unchanged.  Another randomized trial evaluated 35 women either having biofeedback at home versus physical therapy.43   After 12 weeks, a significant improvement on a questionnaire reported improvement of urinary leakage. Sixty-eight percent avoided surgery after 1 year of home biofeedback compared to 52% in the pelvic floor muscle training only group.  This difference, however, was not statistically significant. 

 

Several studies have demonstrated efficacy of biofeedback therapy in the management of urinary stress incontinence in elderly women. The technique helps patients to specifically identify which muscles should be contracted during pelvic floor muscle exercises.  Burgio and coworkers demonstrated treatment efficacy in elderly patients with stress and urge incontinence.44  Patients experienced an 82–94% reduction in incontinence episodes after a mean of 3.5 treatment sessions. More recently, her research group reported a randomized trial in which 222 women between ages 55 and 92 years were randomly assigned to receive 8 weeks of biofeedback-assisted behavioral training, 8 weeks of behavioral training with only verbal feedback based on vaginal palpation, or 8 weeks of self-administered behavioral treatment using a self-help booklet.45  There were similar reductions in incontinence episodes in all groups, and similar improvements in quality of life in all groups.  However, the patients' perceptions of treatment were best in the two active intervention groups. 

 

The efficacy and usefulness of biofeedback therapy remains controversial. Some studies have failed to identify a significant difference between patients treated with biofeedback and those treated with pelvic floor muscle exercises alone.  Mørkved et al. did not find a difference in the effect of individual pelvic floor muscle training with and without biofeedback.46  They conducted a single-blinded, randomized study where all women had 6 months of pelvic floor muscle training supervised by a physical therapist, and one group had a biofeedback device at home and the other group did not.  Both groups showed a statistically significant reduction in leakage after 6 months. Defined by 2 grams or less of leakage on a pad test, the objective cure rate was 58% in women with biofeedback compared to 46% without biofeedback. They did not find any significant difference between the groups after 6 months of treatment.  Hay-Smith and associates conducted a meta-analysis of ten randomized trials that compared biofeedback assisted pelvic muscle training with pelvic muscle training alone.32  There was no statistically significant difference between the groups for rates of self reported cure or improvement, the number of daily leakage episodes, results of pad testing, or measures of muscle activity.  Larger prospective studies with longer follow-up will be helpful to sort out these issues. 

 

Portable biofeedback equipment may be particularly useful for patients who are unable to contract the pelvic muscles effectively at their clinic visit and who live a great distance from the treatment facility. Patients complete their initial training session at the clinic. Subsequent sessions are completed by the patient at home using a portable device.  Most of these devices permit the patient to store data that can be downloaded and reviewed at her follow-up appointments. This permits the patient to perform regular biofeedback sessions at home and still review the efficacy of muscle contractions and overall progress with her clinician.  

 

Electrical Stimulation 

 

Electrical stimulation is another modality that is often used to supplement pelvic floor muscle exercises in an attempt to strengthen these muscles in women with urinary stress incontinence. The treatment has been used for stress, urge, and mixed incontinence. Theoretically, electrical stimulation may help to restore the normal reflex physiology in the muscles of the pelvic floor.  It is also hypothesized that, over time, electrical stimulation can induce a conversion of fast-twitch to slow-twitch fibers, which may improve resting tone of the pelvic floor musculature and the endurance level to perform effective contractions.  A wide variety of treatment regimens have been tried with alterations in the duration, frequency, and intensity of stimulation. Short-term maximal stimulation appears to produce this effect most efficiently, particularly for patients with stress incontinence. 

 

The principles of electrostimulation therapy assume that patients possess intact perineal innervation that can allow them to respond to this form of treatment. It is the stimulation of the pelvic floor afferent fibers that induce the contractions.  However, there are still questions about the exact physiologic effects of electrical stimulation of the pelvic floor. A recent study of the urodynamic changes induced during electrical stimulation revealed that insertion of the vaginal probe may actually induce some physiologic changes.47  In this study, 30 women underwent urodynamics in three phases: a baseline study, a study with a vaginal probe inserted but without electrical stimulation, and a study with electrical stimulation. There was no effect on cystometry with the vaginal probe compared with baseline. However, there were improvements in the urethral functional profile length (FPL), maximum urethral closure pressure (MUCP), and the area of the resting urethral pressure profile (UPP) after insertion of the vaginal probe. There were no significant differences in results between studies with the probe in place but with and without electrical stimulation. This finding suggests that insertion of the probe itself may induce some type of physiologic change that alters these urodynamic parameters. 

 

A systematic review of various adjunctive therapies with pelvic floor muscle training identified seven studies regarding electrical stimulation.48 There was limited evidence from randomized controlled studies stating that electrical stimulation combined with pelvic floor muscle training was effective in women with urinary stress incontinence.  The recurring theme in these studies was that more randomized, controlled trials with larger subject numbers need to be conducted. 

 

A prospective study of a large cohort of women in Norway revealed that home-based electrical stimulation may be effective for the treatment of urinary stress incontinence.49  In this study, 3,198 women were treated with electrical stimulation using a home-managed device.  They performed pelvic floor exercises in combination with electrical stimulation at home.  The overall self-reported improvement was 61%, with 29% of women reporting cure or much improvement.  A survey of the treating physicians revealed their assessment of the patient outcomes to include 33% cured or much improved and 55% improved overall.  Of the total, 44% of patients reported improvement of incontinence severity using a validated severity scale.  In a separate report from this research group regarding patient compliance, only 12% of patients discontinued therapy, and 79% would recommend it to others.50  They concluded that home-based electrical stimulation was a feasible option for women with urinary stress incontinence.

 

All of the adjuvant therapies used to augment pelvic floor muscle exercises require a strong commitment on the part of the patient. An underlying theme in almost all of the available research on these modalities is that patient compliance is critical for any measure of improvement. In this way, the continence outcomes of pelvic floor muscle exercises are similar to the results of all other types of physical exercise programs.  Reimbursement has been an issue for many of the nonsurgical treatment options for the management of urinary stress incontinence. In October 2000, the Centers for Medicare and Medicaid Services (CMS) issued a national coverage decision regarding the use of biofeedback and electrical stimulation for the management of urinary stress incontinence.51  This policy decision was formulated on the basis of an expert review of available data by a panel of physicians involved in the care of incontinent patients. This decision should help to provide treatment for a larger segment of patients who otherwise would not have had access to these forms of therapy.  

 

Acupuncture 

 

Acupuncture has been reported to have various therapeutic effects and a few studies have looked at its impact on stress incontinence.  Chung et al studied the effects on abdominal leak point pressure in rats with urinary stress incontinence.52  Using the Sanyinjiao acupoint located 3 millimeters above the medial malleolus, they measured abdominal leak point pressure as well as the expression of c-Fos, which is an early gene and is a marker in neuronal pathway tracing and activation. The rats that had undergone urethrolysis and acupuncture were found to have a significantly increased abdominal leak point pressure. They also found that in rats that underwent urethrolysis there was an increase in c-Fos expression and that acupuncture significantly decreased the urethrolysis-induced expression of c-Fos, which evokes micturition stimuli. They concluded that acupuncture can be an effective therapeutic approach to stress incontinence. Other studies have looked at its impact, both subjectively and objectively, on urge incontinence and bladder overactivity, and have shown some promising results with improvements in quality of life and reduced leakage with minimal adverse effects.53

MECHANICAL DEVICES

Pessaries, until recently considered a relic of the past, have experienced resurgence as physicians and patients become more conscious of the long-term risks and failure rate of surgical procedures. During the past decade, more types of vaginal and urethral devices have become available. Some patients choose to wear a pessary or device as the final therapy for their pelvic floor dysfunction.  Others use such a device to temporize before considering surgery, and many wear a pessary only when undertaking an activity that results in urine loss, such as exercise.  In our experience and that of others, adverse outcomes from wearing a pessary, such as vaginal abrasions or ulcerations, are rare if a patient is able to insert and remove the pessary on her own and leaves it out overnight at least once per week.54

 

A recent Cochrane Review of mechanical devices for stress incontinence examined six clinical trials including a total of 286 women.55  Two small trials compared the use of mechanical devices to no treatment.   Although the overall evidence was inconclusive, there was a general trend that use of a device improved continence status. The authors concluded that while there is a lack of strong evidence comparing mechanical devices to other treatment modalities, there is little risk involved with these devices and use does not interfere with other future treatments. 

 

The Contiform® incontinence device is shaped similar to a hollow tampon with an arch in the front that provides urethral support, mimicking the effect of a suburethral sling. Three different sizes are available, and the device can be worn up to 1 month.  A total of 41 women with urodynamically documented  stress incontinence and no prolapse were included in a prospective study.56  The group was subdivided according to severity of leakage, and the pad test loss for the total study was significantly reduced by a median of 72%.  This was due to the large reduction in volume of urine loss for the moderate to severely incontinent group, who had a median reduction of 85% from baseline. Regarding quality of life, those with moderate to severe incontinence noted a significant improvement after the use of Contiform. Adverse events included bacterial cystitis, fracture of the anterior curvature of the device, and difficulty removing the device which required additional medical attention. Thirty-six percent of patients subsequently went on to have surgery. The authors concluded Contiform is easy for patients to use and should be offered as an alternative to more invasive surgical procedures. 

 

Noblett et al conducted a prospective study of 95 patients and evaluated the effectiveness of the incontinence dish pessary, particularly with respect to urodynamic parameters and bladder neck support.57  Most of the women in the study had an anterior prolapse, however they found that with the pessary in place, 60% did not leak, whereas 97% leaked without the device in place. 

 

A new disposable intravaginal device (ConTIPI Ltd, Caesaria, Israel) is in development and a trial has been conducted looking at the efficacy and safety in women with stress incontinence.58  Consisting of a core, cover, and applicator, this device is placed intravaginally by patients and is designed to provide tension-free support of the urethra. Main outcomes included the weight of pads and quality of life, as well as subjective reporting of incontinence. A 70% reduction in the weight of pads was recorded in 85% of the women. Subjectively, women reported a daily improvement in incontinence and in quality of life.  

 

A newer pessary is the Uresta™ pessary that is a self-adjusting device with a wide base that provides suburethral support. A small, prospective study with 32 participants found a significant decrease in average scores of weight of pads, incontinence and quality of life questionnaires.59  Sixty-six percent of the patients reported continued use after the 12-month trial. 

 

Various reports have found pessaries to be effective in urinary stress incontinence and emphasis must be placed on proper fitting and positioning of the device.  Also, ease of insertion and removal are key in obtaining optimal benefit and usage for patients. Before a pessary fitting session, we pretreat all postmenopausal women who have vaginal atrophy with estrogen cream unless there is a contraindication due to prior breast or uterine cancer. We instruct women to come to the fitting session with a moderately full bladder, which allows testing of the efficacy of the pessary. Women are instructed to mimic vigorous activity in the clinic area (e.g., brisk walking, jumping jacks, straining) to ensure that the device stops leakage and is comfortable. After the patient demonstrates the ability to void with the pessary in situ, she is sent home with the best fit. We find that the best fit in the office fails to prevent incontinence for approximately one-fourth of women, who then return for further fitting. When the best type and fit is determined, we teach women to insert and remove the device. Because they generally remove the pessary at least once per week, they rarely encounter excessive or malodorous vaginal discharge and have little use for creams other than estrogen. 

 

A recent study used magnetic resonance imaging (MRI) to objectively examine the  anatomic and physiologic factors for restoring continence using pessaries.60  Fifteen women with stress incontinence and urethral hypermobility underwent urodynamics and MRI with and without a pessary in place.  On urodynamics, maximal flow rates decreased, detrusor pressures increased, and functional urethral lengths increased after pessary placement. On MRI, the number of women with funneling decreased, urethral length was greater, posterior urethrovesical angle was more acute, and during Valsalva the bladder neck was elevated farther above the pubococcygeal line with the pessary in place. Only 3 of 15 women leaked after pessary placement. This study provides important anatomical evidence regarding the use of intravaginal devices for the treatment of urinary stress incontinence. 

 

Several different disposable urethral inserts and urethral patches have been developed for the nonsurgical management of urinary stress incontinence in women.61, 62, 63  Although these types of devices have shown promise for select patients in clinical trials, none of are currently commercially available in the United States.

 

PHARMACOLOGIC THERAPY

 

Estrogen 

 

The female urethra and bladder neck contain a rich supply of estrogen receptors, and therefore it is biologically feasible that estrogen replacement could affect postmenopausal urogenital symptoms.  Estrogen promotes vaginal cellular maturation and maintains a more beneficial vaginal flora.  Clinically, estrogen improves symptoms of atrophy such as vaginal dryness, burning, and irritation.  However, the impact of estrogen on urinary stress incontinence is more controversial.  Older nonrandomized studies with subjective outcome measures often reported improvements in symptoms of both urge and urinary stress incontinence.64, 65, 66  However, randomized studies specifically examining stress incontinence have yielded mixed results.  Grady et al. reported the results of a  large prospective randomized trial of estrogen replacement therapy versus placebo in women with heart disease which also provided information on the effect of estrogen plus progesterone on urinary stress incontinence.67  Of 1,525 women with incontinence at baseline, 21% of those receiving estrogen alone reported improvement in urinary stress incontinence compared to 26% of those receiving placebo.  However, 39% of women receiving both estrogen and progesterone reported worsening of their incontinence symptoms compared to 27% of those receiving placebo. In a recent meta-analysis, Moehrer et al. examined 15 randomized trials comparing the use of estrogen to placebo and summarized that the highest subjective cure rates occurred among those treated with estrogen for all types of incontinence.68  Patients with stress incontinence on estrogen reported a statistically better improvement rate of 43% (46/107) versus 27% (29/109) of those receiving placebo. Including all the trials reviewed, approximately 50% of women treated with estrogen were either cured or improved compared to 25% on placebo. However, the studies did find more pronounced effects with urge incontinence compared to urinary stress incontinence. 

 

In contrast, a recent double-blind, placebo-controlled randomized trial assessing the effects of hormone replacement therapy for menopausal symptoms also evaluated the associated  prevalence and severity of incontinence.69  Women were randomized to receive either estrogen alone (0.625 mg/day of conjugated equine estrogen), estrogen plus progestin (0.625 mg/day of conjugated equine estrogen plus medroxyprogesterone acetate), or placebo. It was found that using hormonal therapy increased the incidence of all types of urinary stress incontinence, with stress incontinence having the highest risk (RR for estrogen + progestin = 1.87; 95% CI = 1.26–2.53). The authors concluded that administration of estrogen alone or in combination with progestin should not be used for the prevention or relief of urinary stress incontinence. 

 

Of interest, there is emerging evidence that selective estrogen receptor modulators (SERMs) may impact pelvic floor function in varying ways.  In 6,926 women randomly assigned to either raloxifene or placebo, women receiving the SERM were less likely to undergo surgery for prolapse during the 3-year study period than women receiving placebo (0.7% vs. 1.5%).70  A more recent study examined post-menopausal, post-hysterectomy patients randomized to two different dosages of raloxifene, with one group taking conjugated equine estrogen, and one group taking placebo.71   The results demonstrated that patients treated with conjugated equine estrogen had an increased incidence of urinary stress incontinence. This was not true for raloxifene. The authors concluded that additional studies are needed to fully define the effects of estrogen and selective estrogen receptor modulators on urinary stress incontinence. In contrast, an investigational study of levomeloxifene, a different type of SERM, was halted after 10 months because of a marked increase in urinary stress incontinence.72  In the total group of 2,924 women studied, there was a 17% incidence of incontinence in the study group compared with 4% in the placebo group.  The incidence of pelvic organ prolapse was 7% in the study group versus 2% in the placebo group.  

 

Alpha-Adrenergic Stimulating Agents 

 

The bladder neck and proximal urethra in women contain predominantly alpha-adrenergic receptors.  Stimulation of these receptors produces smooth muscle contraction,  resulting in increased bladder outlet resistance.73  Some women with stress incontinence may improve after treatment with alpha-adrenergic-stimulating drugs.  However, most studies have demonstrated improvement only in women with mild but not severe stress incontinence.74, 75, 76, 77  In the past, drugs such as phenylpropanolamine were used for this purpose.  However, this drug was removed from the market in the United States because of an increased risk of stroke, particularly in younger women. 

 

More recently, a multi-center, randomized, placebo-controlled, crossover study was conducted  examining the effect of Ro 115-1240, an alpha 1A-adrenoceptor subtype agonist, on urinary stress incontinence.78  Thirty-six patients were treated with Ro 115-1240 and 36 received placebo. In patients taking Ro 115-1240, there was a significantly lower mean weekly number of stress incontinence episodes, with a 28% relative improvement compared to placebo.  Stimulation of alpha-adrenoceptors in the vasculature has been a concern with other sympathomimetics, however no differences in mean systolic or diastolic blood pressure were observed between the two groups in this study.  There were some side effects, including scalp tingling, headache, chills, piloerection, and pruritus.  The mean number of pads used and wet pads changed per week was significantly lower in the treatment group compared to placebo. While these results are promising, larger randomized trials will be needed to substantiate these preliminary findings.   

 

Another small, prospective study with 46 patients randomized to either an alpha-adrenergic receptor antagonist or pelvic floor muscle exercises (PFME) demonstrated that overall efficacy was significantly better in the alpha-adrenergic agonist group based on an objective 1-hour pad test.79  Quality of life was improved in both groups, although the gain was significantly better in the alpha agonist group. 

 

Imipramine hydrochloride, an antidepressant with both alpha-adrenergic agonist and anticholinergic effects, appears to improve symptoms in some women with urinary stress incontinence. In a nonrandomized trial in which 30 women received 75 mg of imipramine hydrochloride daily for 4 weeks, 71% stated that they were continent after treatment with imipramine but 9% had no improvement.80  The maximum urethral closure pressure and functional urethral length increased significantly after treatment. However, the closure pressure also increased markedly in women who remained incontinent. Prospective, randomized, controlled trials to verify this high success rate are currently not available, however anecdotal clinical evidence suggests that the actual success rates may be lower.  

 

Theoretically, beta-adrenergic blocking agents may be expected to potentiate an alpha-adrenergic effect, thereby increasing resistance in the urethra.  Kaisary reported success in treating stress-incontinent patients with the beta-adrenergic blocking agent propranolol.81  Although such treatment has been suggested as a theoretical alternative drug therapy in patients with sphincteric incompetence and hypertension, no reports of such combined efficacy have appeared.  

 

Serotonin Reuptake Inhibitors

 

Serotonin and norepinephrine reuptake inhibitors are another class of drugs that may show promise for the treatment of urinary stress incontinence in women. There are data to suggest that serotonergic activity may be involved in both stress and urge incontinence. A recent study using an animal model revealed that rats treated with clomipramine to induce a state of depression demonstrated changes related to overactive bladder, including alterations in voiding frequency and unstable bladder contractions.82  These authors found that administration of fluoxetine reversed these changes. This suggests that treatment with selective serotonin reuptake inhibitors may be of potential benefit in women with mixed stress and urge incontinence. There are associations between depression and urinary stress incontinence, and this type of therapy with SSRIs might prove promising for treatment of these combined conditions in humans.83 

 

Duloxetine, a selective serotonin and norepinephrine reuptake inhibitor, increases serotonin and norepinephrine levels in the sacral spinal cord, thereby enhancing pudendal nerve activity.  This in turn leads to increased contraction of the external sphincter. In 2004, duloxetine was approved in Europe, the Middle East, and portions of Central and South America for the treatment of urinary stress incontinence in women.  A large, randomized, placebo-controlled trial examined the impact of duloxetine on stress incontinence in women.84  A total of 553 women between 18 and 65 years of age were randomly assigned to placebo or to three different doses of medication. After 12 weeks, the median incontinent episode frequency decreased in all the groups, with the greatest reduction in women using the largest dose of 80 mg duloxetine per day. In this group, the median incontinence frequency decreased by 64% compared with 41% in women using placebo. Five percent of women using placebo discontinued treatment, compared with 15% of those receiving the highest dose of medication. More recently, a randomized, placebo-controlled, double-blind study evaluated the efficacy and safety of duloxetine for treatment of urinary stress incontinence in women.85  Sixty Taiwanese women took 40 mg of duloxetine twice daily while 61 women were assigned to placebo. At 8 weeks, 66% of patients assigned to the treatment group remained in the study compared to 87% in the placebo group. The frequency of incontinent episodes was significantly reduced in the duloxetine group (69.9%) versus placebo (42.%).  Duloxetine use was associated with a significant improvement in quality of life as measured by the Global Impression of Improvement questionnaire, although no difference was identified using the Incontinence Quality of Life questionnaire. The most common side effects were dry mouth, constipation, nausea, somnolence, and dizziness.  Of these, dizziness was the most common adverse event leading to study discontinuation.  

 

Currently, there are no medications approved by the United States Food and Drug Administration (FDA) specifically for the treatment of urinary stress incontinence in women.

CONCLUSIONS

Unfortunately, no single treatment exists that can cure all women with urinary stress incontinence. Although conservative management cures fewer women than surgery, the low risk and expense and reasonable overall improvement rates associated with conservative therapy combine to make these approaches attractive as a first line of therapy for many women.  Additional basic science and clinical research will likely lead to more non-surgical options for the treatment of female urinary stress incontinence in the future.

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