phytoestrogens and Urinary-Incontinence

Because exogenous estrogen treatment has been associated with a higher risk of urinary incontinence, our objective was to evaluate the longitudinal relationships of dietary phytoestrogen intakes (isoflavones, coumestans, and lignans) and the development of incontinence in midlife women transitioning through menopause.. The Study of Women's Health Across the Nation (SWAN) Phytoestrogen Study was developed within SWAN, a community-based, multisite, multiracial/ethnic, prospective cohort study. SWAN interviewers administered a food consumption assessment at baseline and on follow-up visits 5 and 9. The SWAN Phytoestrogen Study created a phytonutrient database that allowed estimation of the usual daily intakes of four isoflavones, four lignans, and coumestrol. On an annual self-administered questionnaire, participants reported on the frequency and type of incontinence. We used discrete proportional hazards models to evaluate whether the estimated daily intake of each phytoestrogen class on the visit previous to the first report of incontinence was associated with the development of monthly or more incontinence versus remaining continent.. We found no association or patterns of association between developing any, stress, or urge incontinence and the reported daily dietary intake of isoflavones, coumestrol, and lignans on the visit previous to the onset of incontinence.. The results of this longitudinal study provide important information to better understand estrogenlike substances in the continence mechanism of midlife women. Our study shows that neither high nor low dietary intakes of isoflavones, coumestrol, and lignans prevent stress or urge incontinence. Future studies should evaluate whether serum levels of phytoestrogens or their metabolites impact incontinence symptoms.

Topics: Adult; Cohort Studies; Coumestrol; Diet; Ethnicity; Female; Humans; Isoflavones; Lignans; Longitudinal Studies; Menopause; Middle Aged; Phytoestrogens; Prospective Studies; Surveys and Questionnaires; Urinary Incontinence; Women's Health

Whether urinary incontinence in the postmenopause can be prevented or delayed by estrogens is currently controversially debated. Ovariectomized (ovx) rats have been successfully used as models in the past years but plant derived substances with estrogenic effects in the lower urinary tract have not been studied so far. Therefore we compared the effects of a 3 months lasting oral administration of estradiol 17beta (E2) with those of the phytoestrogens equol, genistein and puerarin. They were ovariectomized, fed with test substance containing food and then anaesthetized and catheterized with a biluminal catheter having one outlet in the bladder and another in the urethra at the level of the urethral sphincter. Urethral and bladder pressure were recorded during a 240s period of retrograde bladder filling (2 x 0.5 ml within 30s with 1 min filling intermission). Bladder and urethra pressures were highest in the E2>puerarin>equol>genistein treated animals. Phytoestrogen and E2 treatment resulted in consistently higher urethral than the bladder pressures during the filling period and in the filled status whereas bladder often exceeded urethral pressures in ovx controls. In summary, we demonstrate significant improvement of urethral closure mechanism under E2 and phytoestrogen administration that can be assumed to be beneficial for prevention or therapy of postmenopausal urge incontinence.

Topics: Aging; Animals; Equol; Estradiol; Female; Genistein; Isoflavones; Ovariectomy; Phytoestrogens; Pressure; Rats; Rats, Sprague-Dawley; Urethra; Urinary Bladder; Urinary Incontinence; Urodynamics