Objectives: To evaluate whether the increasing occurrence of urinary and voiding dysfunction is independently influenced by the transition from pre- to postmenopause or by the interactive and additive effects of age-associated changes in bladder and urethral function.
Design: Of the 1,584 women randomly sampled from a community-based health population, 1,253 (79.1%) were successfully interviewed. The participants were asked to reply to the Bristol Female Urinary Tract Symptoms Questionnaire regarding various storage symptoms and voiding dysfunction. The χ2 test and Cochran-Armitage trend test were used for analysis.
Results: The prevalence of storage symptoms such as frequency, urgency, nocturia, and urge incontinence in premenopausal and menopausal groups was 18.0% versus 29.8%, 9.8% versus 20.7%, 21.2% versus 38.2%, and 6.8% versus 15.7%, respectively (all P < 0.05). In premenopausal and menopausal groups, the prevalence of hesitancy, poor stream, incomplete emptying, voiding with abdominal straining, discontinuous urine flow, and dribbling was also significantly different (17.2% v 22.9%, 17.8% v 25.7%, 12.7% v 21.9%, 4.9% v 11.6%, 16.2% v 24.5%, and 9.4% v 17.6%, respectively; all P < 0.05). However, the occurrences of various storage symptoms, namely, frequency, urgency, nocturia, and urge incontinence, as well as voiding symptoms such as incomplete emptying, discontinuous urine flow, and dribbling, were also significantly associated with the normal aging process (P < 0.05).
Conclusions: Our results imply that the increasing occurrences of storage and voiding dysfunctions are not only affected by pre- and postmenopausal transition but are also closely associated with aging changes.
A higher life expectancy, owing to modern medical achievement, allows women to spend more than one third of their lifetime in the menopausal period. The number of women with lower urinary tract dysfunction complaints is expected to increase in the future. 1
The postmenopausal hypoestrogen status has been associated with anatomic and physiologic changes, such as thinning of the urethral mucosa, loss of urethral closure pressure, and decreased sensory threshold of the lower urinary tract. 2–4 Menopause is also associated with a marked reduction in endogenous estrogen production, and, as a result, lower levels of circulating blood estrogen have various deleterious effects on the urogenital tract. The urogenital epithelium may become atrophied, dry, and inflamed and may contribute to urinary symptoms, including frequency, urgency, nocturia, dysuria, incontinence, and pelvic laxity. 1,5
Gilpin et al 6 found that a significant linear reduction in the amount of acetylcholinesterase-positive nerves and a reduction in the number of nerve axons in human detrusor muscle tissue take place with increasing age. These findings may be associated with a variety of functional bladder impairments in advanced age. In animal models, Lin et al 7 demonstrated that there was a progressive decrease in the contractile response to repetitive autonomic stimulation (increase in fatigue) in aging rats' bladder strips. They concluded that a progressive reduction in the rate of high energy phospate generation, which significantly increases the rate of fatigue of the bladder smooth muscle, is associated with aging. 7 Levin et al 8 discovered that the rate of power generation, the percent of emptying, and the amount of work performed by bladders in old rabbits was significantly less than the bladders of young rabbits. Aging is associated with a progressive reduction in the ability of the bladder to sustain increased tension for bladder emptying. 8 Ouslander 9 indicated that lower urinary tract symptoms and disorders are prevalent in the aging population. Older men and women have common symptoms, including frequency, nocturia, urgency, and incontinence. 9 Homma et al 10 conducted a survey and urodynamics on an older population who had no spontaneous complaints of symptoms and revealed that nearly all of the urinary symptoms increased with age. In women, the detrusor function such as maximal detrusor pressure and maximal flow rate progressively deteriorated with age. 10 These results are consistent with the report by Malone-Lee and Wahedan, 11 who also discovered that voiding dysfunction increased with age because of failure on the initiation of voiding.
Whether the increasing occurrence of urinary and voiding dysfunction is independently influenced by the transition from pre- to postmenopause or by the interactive and additive effects of age-associated changes in bladder and urethral function needs to be investigated. To elucidate this issue, we randomly sampled women from a community-based health population. The aim of this study was to assess the occurrence of storage and voiding symptoms as a result of menopause and the prevalence of various symptoms significantly associated with the normal aging process.
From the 1School of Physical Therapy, 2Department of Obstetrics and Gynecology, 3Institute of Stomatology, Dental School, 4School of Nursing, and the 5Department of Epidemiology, Chung Shan Medical University and Hospital, Taichung, Taiwan.
Received July 11, 2002; revised and accepted September 26, 2002.
This study was supported in part by a grant from the National Science Council in Taiwan (NSC-89-2314-b-040-046).
Address reprint requests to Gin-Den Chen, MD, Department of Obstetrics and Gynecology, Chung Shan Medical University Hospital 110, Section 1, Chien-Kuo N. Road, Taichung 40201 Taiwan. E-mail: email@example.com.