Special Report I
Urinary incontinence is defined as an involuntary urine leakage under the definition of International Continence Society and is classified into stress-type, urgency-type, mixed-type, and overflow-type. Stress urinary incontinence (SUI) is involuntary urine leakage when abdominal pressure increases, such as cough, sneezing, and straining. Its major pathogenesis can be largely explained by two mechanisms; hypermobility of bladder neck and urethra when abdominal pressure increases due to postpartum weakening of pelvic muscle and pelvic atony in women; and deficiency of urethral sphincter itself.
Decline in quality of life and expenditure of medical bill due to urinary incontinence can give a great influence in women’s social life. Prevalence of female urinary incontinence is 30~40% in younger women, increases in middleaged women up to 30~50%, and stays at such level in older women. In regard to type of urinary incontinence, SUI is most common with 49%, second most common is mixed-type urinary incontinence with 29% and third most common is urgency-type urinary incontinence with 21%. As for prevalence in Korea, 24.4-41.2% complained of urinary incontinence when analyzing 1,000 or more women. Of those, SUI constituted 48.8%, mixed-type 41.6%, and urgency-type 7.7%, in which prevalence of SUI was the highest. Influence of urinary incontinence is not to be overlooked in socio-economical and individual aspects. Though there are not much data in Korea, based on data from western countries, more than 1.1 million patients in the U.S visited hospital for urinary incontinence as their chief complaints in year 2000 alone, and the amount spent in its diagnosis and treatment was 19.5 billion dollars, which is safe to say that it caused more socioeconomical loss than any other chronic diseases. Analysis of individual patients revealed that women with severe urinary incontinence showed more severe depression, negative thoughts and lower satisfaction in quality of life, which induced various physical and psychological disorders.
SUI is majorly due to weakening of pelvic musculature and urethral sphincter and when some severe SUI symptoms arise to a certain level, surgical treatment is mostly conducted in Korea. But when symptom of the patient is not severe or patient refuses the surgery due to health status, there are some conservative treatments to improve symptoms. Conservative treatments of SUI include modification of life style, behavior therapy, and pelvic floor muscle exercise (PFME). Modification of life style is to alleviate symptoms of urinary incontinence by modifying chronic constipation, obesity, smoking, and caffeine intake, but its scientific evidence is weak to routinely approve such approach. Behavior therapy includes bladder training and education of voiding mechanism and is mostly effective in urgency-type urinary incontinence. Though it has been reported that it decreased around 50% of urinary incontinence in treatment of SUI, its effects in clinical practice is restrictive as the patient’s motive in therapy is crucial.
PFME, among treatment of SUI, was first proposed by Dr. Arnold Kegel in 1948 for prevention and treatment of post-partum urinary incontinence and various modifications have been attempted to improve its therapeutic effect. Theological background of PFME is to increase muscular capacity with exercise and support pelvic organ structurally, preventing descent of bladder neck and urethra with quick pelvic floor muscle contraction when abdominal pressure abruptly increases. To be more specific, it is to enhance passive urinary continence by placing pelvic organ with reinforcing and hypertrophying pubo-coccygeous muscle among anal elevating muscles and active urinary continence of bladder neck and urethra with repetitive contraction exercise. In order for PFME to be effective, selection of appropriate patients is crucial. PFME has no side effect and does not affect other treatment so it can be utilized as primary treatment of SUI. However, it is more effective in patients with less severe symptoms, patients receiving estrogen therapy after menopause, patients with normal body weight, and patients with no history of previous urinary incontinence surgery. The most important point is that patient must recognize contraction and relaxation of pelvic muscle from education. To be said, muscles other than pelvic floor muscles like abdominal or buttock muscles should not contract and only pelvic floor muscles should be selectively contracted and relaxed for its maximum effect. There is no standard guideline on training frequency or repetition of PFME, but International Continence Society recommends 8 to 10 repetition with 6 to 8 seconds of contraction each time exercised 3 to 4 times a week. As for duration, it is recommended to be continued for at least 15 to 20 weeks. In recent meta-analysis, PFME showed cure rate of 56%, which showed improvement in cure rate of 8 times than control group and overall improvement rate of 17 times than the control group. Therefore, it can be effective as a primary treatment for SUI in optimal patient group.
Among PFME methods, 4 methods are commonly used in order to increase cognition of pelvic floor in patients and increase exercise outcome. Vaginal cone uses heavier vaginal cone stage by stage for patient to exercise while identifying pelvic floor muscle and has been approved of its effect from meta-analysis. In some cases, electrical stimulation and extracorporeal magnetic therapy can be conducted simultaneously with PFME, but the protocol has not yet been established and there are many negative opinions on its long-term effect.
Biofeedback includes all methods that give direct audiovisual stimuli to patient during exercise and modifying cognition and contraction of pelvic floor muscle. About 30% of patients were incapable of contracting pelvic floor muscles adequately when they heard PFME method via literature or verbal instruction, and biofeedback was introduced to supplement such problem and enhance its effect. In conclusion, it is to give feedback to patients by showing electro-musculography or sphincter pressure as audiovisual cues and train them repeatedly until they can selectively control the proper muscle. Though there is no standard guideline on biofeedback in PFME, continuous education is recommended after education of 30 minutes or longer, 2 or more times a week, for more than 1 month. In regard to simultaneous treatment of biofeedback in PFME, there are many conflicting reports on its significance in therapeutic effect, but it is recognized to be helpful in faster relief of urinary incontinence. Previous studies found PFME with biofeedback to be more effective in improvement of pelvic floor muscle contraction than PFME alone, whereas one study reported PFME with biofeedback to be more effective in improving pelvic floor muscle contraction, but with no additional benefit of average decrease in urinary incontinence. From analysis of 10 randomized studies, PFME with biofeedback was reported to be no more effective than PFME alone, but recent meta-analysis reported PFME with biofeedback to have some more advantage in improvement rate than PFME alone. In addition, one recent study reported that PFME with biofeedback alleviated SUI symptoms in earlier stage with use of new biofeedback device that uses vibration.
Such result of PFME treatment with biofeedback is facilitating many portable biofeedback PFME devices to be sold in market so that home training would be possible, rather than in hospital. Such portable devices use various biofeedback methods and increase outcome of PFME with improvement of probe mechanism. The most typical method would be to measure intra-vaginal pressure with intra-vaginal probe when the patient is conducting PFME and provide feedback after assessing whether patient is conducting PFME properly, which is clinically safe and shows great effect in relief and treatment of urinary incontinence. Such portable biofeedback devices are clinically safe and show great effect in relief and treatment of urinary incontinence. These devices also help achieve improvements in sexual function.
Seong-Jin Jeong, M.D.
Professor of Urology, Seoul National University Bundang Hospital
Professor Jeong is an active clinician and surgeon in the field of voiding dysfunction and prostatic diseases, such as overactive bladder, incontinence, neurogenic bladder, and benign prostatic hyperplasia (BPH). He has conducted researches on various receptors in the urothelium and detrusor muscle, and plans to develop organ bath experiments. Professor Jeong is currently actively involved in the surgical treatment of male incontinence and in neuromodulation for overactive bladder. Also, he combines medical treatments for patients with various voiding dysfunctions.