Introduction: The State of Urinary Incontinence in Women

INTRODUCTION The State of Urinary Incontinence in Women Victor W. Nitti, MD Department of Urology, New York University School of Medicine, New York, NY [Rev Urol. 2004;6(suppl 3):S1-S2] © 2004 MedReviews, LLC tress urinary incontinence (SUI) is a common condition affecting millions of women in the United States. SUI is defined as loss of urine with exertion or an increase in abdominal pressure that occurs with activities such as coughing, sneezing, walking, and bending, among others. This condition is distinctly different from urge incontinence, which is loss of urine preceded by an urge or desire to void that is caused by detrusor overactivity. Stress and urge incontinence often exist together as mixed incontinence. The observed prevalence of stress incontinence in the female population has been reported to be between 4% and 35%, depending on its “epidemiologic definition.” Needless to say, SUI can significantly reduce quality of life and impair the ability to perform routine daily activities. Traditional therapies for SUI have involved conservative treatments, such as behavior modification, perhaps with institution of a pelvic floor exercise program, as well as definitive or “aggressive” treatments, such as surgery and urethral bulking agents. We have recently gained new insights into the physiology of the lower urinary tract, specifically with respect to neurotransmitters and the role of the central nervous system. This information has helped to create fertile ground for the research and development of new methods of treating lower urinary tract dysfunction, including SUI. This supplement begins with a thorough review, by Karl Luber, MD, of the definition, epidemiology, and risk factors associated with SUI. An understanding of how SUI has been defined “epidemiologically” helps the reader to understand not only the prevalence of this condition and the number of women affected but also the degree to which these women are affected. A clearer understanding of risk factors is also critical as we develop ways to prevent this condition. S VOL. 6 SUPPL. 3 2004 REVIEWS IN UROLOGY S1 Introduction continued Jeffrey Cundiff, MD, follows with a review of the pathophysiology of SUI. Presented as a “chronology of theories,” this overview nicely depicts where we have been and where we are going regarding our understanding of SUI. Historically, SUI has been viewed as an “anatomical disorder”; however, modern theories take into account both anatomy and function of the lower urinary tract. To provide a more complete understanding of lower urinary tract functioning, Michael Chancellor, MD, and Naoki Yoshimura, MD, PhD, describe the neurophysiology of SUI. Here, information is provided on lower urinary tract neurotransmitters, as well as S2 VOL. 6 SUPPL. 3 2004 the mechanisms by which the central nervous system controls the functioning of the lower urinary tract. The second half of this supplement is dedicated to the treatment of SUI. Eric S. Rovner, MD, and Alan Wein, MD, present a comprehensive overview of the available SUI treatments, including their known outcomes, benefits, and risks. This is followed by a discussion of duloxetine, a novel pharmacotherapy for SUI that is currently being investigated. Victor Nitti, MD, describes this serotonin/norepinephrine reuptake inhibitor and its effects on the lower urinary tract (particularly the external sphincter), as well as its REVIEWS IN UROLOGY pharmacokinetics and metabolism. Roger Dmochowski, MD, then presents the current clinical data available for duloxetine; specifically, the safety and efficacy data from phase 2 and 3 trials are discussed. As our understanding of lower urinary tract function grows, so too does our ability to treat conditions and diseases that cause dysfunction of the lower urinary tract. I hope that you will find this supplement informative and useful. Further insight into the mechanisms behind lower urinary tract dysfunction, as well as the development of novel therapies, can only be beneficial to the millions of women who suffer from SUI.