Clinical Consult

Each month, questions with a common theme will be selected and answered comprehensively by one of our Steering Committee members. Previously answered questions will be archived each month for your reference. If you wish to submit a question, click here.

This Month's Questions:

1. What are the effects of estrogen, with and without progestin, on stress urinary incontinence?
   Response by Mikel L. Gray, PhD, CCCN, CUNP
   
   
2. What urinary incontinence issues do women face in the workplace, and what are the available management options?
   Response by Mary H. Palmer, PhD, RNC, FAAN

1. What are the effects of estrogen, with and without progestin, on stress urinary incontinence?

Response by Mikel L. Gray, PhD, CCCN, CUNP, posted 06/30/2005:

Because the average age at which menopause begins is 51 years, a third of a woman's life may be characterized as postmenopausal.¹ Hormone replacement therapy (HRT), administered as either estrogen alone or estrogen plus progesterone, has been used for decades for symptomatic relief of hot flushes, night sweats, and vaginal dryness. In addition, HRT has been administered in an attempt to improve bothersome lower urinary tract symptoms, including urinary incontinence.²

As the bladder stores urine, continence relies on intraurethral pressure exceeding intravesical pressure.^1,3 Compromise of the urethral sphincter's ability to create a watertight seal may result in stress urinary incontinence (SUI).¹ SUI, characterized by the involuntary loss of urine during physical exertion, such as coughing, sneezing, or laughing, is a common form of urinary incontinence in women.⁴ It occurs when the urethral-sphincter complex is suddenly and temporarily overwhelmed by a rise in abdominal pressure during physical activity or when coughing or sneezing.³

During embryonic development, the vagina and urethra arise from the urogenital sinus, and both contain estrogen and progesterone receptors.⁵ Among adult women, estrogen receptors abound throughout the lower urinary tract, and the trigone and urethra in particular, and circulating estrogen exerts a trophic effect on these tissues, promoting the growth and maintenance of both local urothelium and the underlying mucosa.⁶ However, estrogen deficiency associated with the climacteric leads to atrophy of this mucosal tissue, with dryness and thinning of the vaginal and urethral lining.^2,4 Loss of elasticity in the vagina and a reduction of urethral closure pressure are often the results.²

These and other biologic mechanisms provided a rationale for the use of HRT for the treatment of bothersome lower urinary tract symptoms, including incontinence, among postmenopausal women. Previously, uncontrolled case series studies suggested a benefit from HRT; but several more recent randomized clinical trials of the effect of opposed or unopposed HRT have found that HRT slightly increases rather than reduces the frequency of incontinence episodes.²

For example, the Women's Health Initiative (WHI) Hormone Trials were large, multicenter, placebo-controlled, randomized clinical trials whose primary aim was to assess for coronary heart disease in postmenopausal women.⁷ A large cohort of women (N=16,608) who had not undergone hysterectomy were enrolled in a trial comparing opposed HRT (estrogen plus progesterone), and a second group (N=10,739) who had undergone hysterectomy were enrolled in an estrogen-only trial.⁷ During these trials, questionnaires were used to obtain comprehensive information on urinary incontinence at baseline, at 1 year in all participants, and at 3 years in a subset of patients.² When the effects of both HRT regimens in the WHI trials on SUI, urge urinary incontinence (UUI), and mixed urinary incontinence were examined, neither group achieved improvement in urinary incontinence. Instead, the researchers reported that both groups experienced a slight increase in the risk of new-onset or worsening SUI.² Grady and colleagues⁸ found a similar increase in a group of 1,525 women who were administered opposed HRT.

Based on these data, some researchers have concluded that systemic HRT should not be prescribed for the treatment of urinary incontinence in postmenopausal women aged 50 years or older.^2,6 However, an investigational serotonin and norepinephrine reuptake inhibitor has been demonstrated in clinical trials to reduce the frequency of SUI episodes in women,⁹ and these findings suggest that this may be an efficacious option for the treatment of SUI.

References

1. Maloney C. Estrogen and recurrent UTI in postmenopausal women. Am J Nurs. 2002;102:44-52.
   
   
2. Hendrix SL, Cochrane BB, Nygaard IE, et al. Effects of estrogen with and without progestin on urinary incontinence. JAMA. 2005;293:935-948.
   
   
3. Gray M. Stress urinary incontinence in women. J Am Acad Nurse Pract. 2004;16:188-197.
   
   
4. Newman DK. Stress urinary incontinence in women: involuntary urine leakage during physical exertion affects countless women. Am J Nurs. 2003;103:46-55.
   
   
5. Ishiko O, Hirai K, Sumi T, Tatsuta I, Ogita S. Hormone replacement therapy plus pelvic floor muscle exercise for postmenopausal stress incontinence: a randomized, controlled trial. J Reprod Med. 2001;46:213-220.
   
   
6. DuBeau CE. Estrogen treatment for urinary incontinence: never, now, or in the future? JAMA. 2005;293:998-1001.
   
   
7. Writing Group for the Women's Health Initiative Investigators. Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results from the Women's Health Initiative randomized controlled trial. JAMA. 2002;288:321-333.
   
   
8. Grady D, Brown JS, Vittinghoff E, Applegate W, Varner E, Snyder T; the HERS Research Group. Postmenopausal hormones and incontinence: the heart and estrogen/progestin replacement study. Obstet Gynecol. 2001;97:116-120.
   
   
9. Dmochowski RR, Miklos JR, Norton PA, Zinner NR, Yalcin I, Bump RC; for the Duloxetine Urinary Incontinence Study Group. Duloxetine versus placebo for the treatment of North American women with stress urinary incontinence. J Urol. 2003;170:1259-1263.

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2. What urinary incontinence issues do women face in the workplace, and what are the available management options?

Response by Mary H. Palmer, PhD, RNC, FAAN, posted 06/30/2005:

Urinary incontinence is an important women's health issue.¹ There are 3 general categories of urinary incontinence – stress urinary incontinence (SUI), urge urinary incontinence (UUI) or overactive bladder, and mixed urinary incontinence (mixed UI). SUI is the most common form of urinary incontinence in women younger than 60 years, and it is characterized by the loss of urine resulting from an increase in intra-abdominal pressure during activities such as coughing, sneezing, lifting, or exercising. UUI is “the complaint of involuntary leakage accompanied by or immediately preceded by urgency.”² Mixed UI is a combination of symptoms of SUI and UUI.² Research has focused on the causes of urinary incontinence and its management, but little is known about the effects it has on women who work outside the home.¹

Women will make up 48% of the US workforce by 2008, with 60% of the total female population older than 16 years employed outside the home.³ Although the US economy is changing from manufacturing to more service-oriented jobs, many women continue to work in factories, on assembly lines, and in other production facilities. This kind of work may involve heavy lifting, bending, working in awkward positions, and repetitive motion, which may put these women at greater risk for urinary incontinence.⁴

Women working in production are not the only ones affected by urinary incontinence. Palmer and colleagues⁵ reported on a survey of 1,113 working women in an academic setting, which indicated that 21% of these self-reported healthy women experienced urinary incontinence at least monthly. Only one third of these women said they believed their incontinence was an important problem that needed to be resolved, and less than half had reported their urinary incontinence to their clinician. However, 81% said they would welcome more information about urinary incontinence.⁵

Fitzgerald and colleagues⁴ surveyed 265 women who worked in a manufacturing factory. From that population, 29% were categorized as having urinary incontinence and 35% of those categorized as having urinary incontinence reported that they had told their clinician. Several of these women reported feelings of embarrassment when they experienced accidental urine loss at work.⁶ Similar to the women in the academic setting, 85% said they were interested in learning more about urinary incontinence.

In a comparative study, Palmer and Fitzgerald¹ found a significant difference in the prevalence of urinary incontinence between an academic-setting group (group A) and a group of women working in a manufacturing factory (group B; 21% vs 29%, respectively; P=.003). More women in group A reported symptoms of SUI (36%), whereas group B reported a higher prevalence of symptoms of mixed UI (73%).

Strategies for management differed between the 2 groups. Women in group B were more likely to opt for management of their urinary incontinence by using containment products (ie, panty liners) than group A (77.8% vs 58.3%, respectively; P=.003). However, group A was more likely to opt for more treatment-oriented behavior modification and use voiding schedules (28.1% vs 10.9%, respectively; P=.009) or pelvic floor muscle (PFM) exercises (44% vs 28.8%; P=.04) than group B.¹ One strategy women used to manage urine loss is of concern. More than 25% of women in group A and 32% of women in group B limited oral fluids, thus risking dehydration. Successful application of voiding schedules and correctly performed PFM exercises have been shown to reduce or even reverse urinary incontinence.⁷

In a study by Davis et al,⁸ 563 female active-duty soldiers completed a questionnaire regarding the prevalence of urinary incontinence symptoms during the performance of their duties and physical training. More than 30% reported problematic leakage. Of these, 68% stated that they commonly took measures (eg, emptying bladder or wearing pads) as a precaution against urinary incontinence before strenuous activity, and 11% stated they used mechanical devices such as tampons or pessaries.

Similarly, Sherman and colleagues⁷ found that one third of 450 active-duty female soldiers reported problems with urinary incontinence during field training activities. Thirteen percent of the respondents significantly restricted fluid intake during field training. In addition to the considerable risk of dehydration, women who restrict their fluid intake while working or exercising to avoid frequent use of the toilet have a 2.21-fold higher risk of urinary tract infection.⁹

References

1. Palmer MH, Fitzgerald S. Urinary incontinence in working women: a comparison study. J Womens Health. 2002;11:879-888.

2. Abrams P, Cardozo L, Fall M, et al. The standardisation of terminology of lower urinary tract function: report from the Standardisation Sub-committee of the International Continence Society. Neurourol Urodyn. 2002;21:167-178.

3. Fullerton HN Jr. Labor force projections to 2008: steady growth and changing composition. Month Lab Rev. 1999;11:19-32.

4. Fitzgerald ST, Palmer MH, Kirkland VL, Robinson L. The impact of urinary incontinence in working women: a study in a production facility. Women Health. 2002;35:1-16.

5. Palmer MH, Fitzgerald S, Berry SJ, Hart K. Urinary incontinence in working women: an exploratory study. Women Health. 1999;29:67-82.

6. Fitzgerald ST, Palmer MH, Berry SJ, Hart K. Urinary incontinence: impact on working women. AAOHN J. 2000;48:112-118.

7. Sherman RA, Davis GD, Wong MF. Behavioral treatment of exercise-induced urinary incontinence among female soldiers. Mil Med. 1997;162:690-694.

8. Davis G, Sherman R, Wong MF, McClure G, Perez R, Hibbert M. Urinary incontinence among female soldiers. Mil Med. 1999;164:182-187.

9. Nygaard I, Linder M. Thirst at work – an occupational hazard? Int Urogynecol J Pelvic Floor Dysfunct. 1997;8:340-343.

10. Dmochowski RR, Miklos JR, Norton PA, Zinner NR, Yalcin I, Bump RC; Duloxetine Urinary Incontinence Study Group. Duloxetine versus placebo for the treatment of North American women with stress urinary incontinence. J Urol. 2003;170:1259-1263.