URINARY INCONTINENCE--REPRODUCTIVE/HORMONAL RISK FACTORS

Stanford University, Stanford CA

Investigators

Linked publications & trials

Abstract

DESCRIPTION: (Adapted from Investigator's Abstract) The proposed epidemiologic study will assemble a retrospective cohort of long-term female members of a large health maintenance organization to determine the association between specific childbirth (parturition) events, hysterectomy, hormone use and urinary incontinence (UI) in later life. The study will also provide important descriptive information on UI by type, age group, ethnicity, severity and age of onset. Childbirth, hysterectomy and hormone use have all been implicated as risk factors for UI based on previous epidemiologic studies. Physiologic studies suggest that pelvic nerve and muscle damage during parturition may be associated with an increased risk for UI in the post-partum period. While UI is relatively uncommon after the immediate post-partum period, its prevalence increases with age. Apparently, however, no study has examined the relationship between specific reproductive events and UI in later life. The proposed study will enroll 2,100 ethnically diverse women ages 40 to 69 who have been members of a large health maintenance organization, Kaiser Permanente Medical Care Program (KPMCP) of Northern California, continuously since age 18. KPMCP has archived medical records for all members since 1946. Onset of UI, as well as lifetime reproductive history and hormone use, will be assessed using life event calendar methods. Type of UI (stress, urge and mixed) will be determined by in-person interviews. The primary outcome variable will be time to onset, by type, of "regular" UI, defined as UI occurring at least once per month for at least 3 consecutive months, exclusive of pregnancy and the first 3 post-partum months. Severity of UI will also be assessed and examined as an outcome. Specific potential risk factors associated with parturition, including use of forceps, episiotomy, oxytocin, perineal tears, anesthesia, length of labor and infant birth weight will be abstracted from the labor and delivery records. Detailed descriptions of hysterectomy/oophorectomy will be abstracted from surgical records. Multivariate analysis will be used to estimate the risk of UI associated with each of the exposure variables of interest independent of other exposure variables and covariables. The investigators note that because UI is a common condition with substantial economic and quality of life impact, identifying modifiable risk factors for UI would have a potentially large impact on public health.