discuss their bladder symptoms during the testing. The status of the recruited participants and .... examinations and urodynamic studies were not performed on ...
BJUI
Comparisons of pelvic floor muscle performance, anxiety, quality of life and life stress in women with dry overactive bladder compared with asymptomatic women
BJU INTERNATIONAL
Sharon Knight, Janis Luft*, Sanae Nakagawa and Wendy B. Katzman† Department of Obstetrics, Gynecology and Reproductive Sciences, *Department of Family Health, UCSF School of Nursing, †Department of Physical Therapy and Rehabilitation Science, University of California, San Francisco, CA, USA Accepted for publication 13 June 2011
Study Type – Therapy (case control) Level of Evidence 3b OBJECTIVES • To determine if pelvic floor muscle surface electromyography (sEMG) measurements differed between women with dry overactive bladder (OAB) symptoms and asymptomatic controls. • To determine whether pelvic floor muscle performance was associated with anxiety scores, quality of life and life stress measures PATIENTS AND METHODS • We enrolled 28 women with urinary urgency and frequency without urinary incontinence, and 28 age-matched controls. • sEMG was used to assess pelvic muscle performance. • Participants also completed the Beck Anxiety Inventory, Pelvic Floor Distress
INTRODUCTION Overactive bladder (OAB) describes the symptoms of urinary urgency, frequency, nocturia and urge incontinence that affect approximately 16% of women in the USA [1]. Many women with OAB do not have incontinence, with an estimated prevalence of 7.6% for continent/dry OAB [2], but incontinence occurs in ≈50% of patients presenting clinically
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What’s known on the subject? and What does the study add? Abnormal pelvic floor muscle function has been associated with chronic pelvic pain syndromes. This study adds evidence about pelvic muscle performance in women with dry overactive bladders. Inventory, Pelvic Floor Impact Questionnaire and Recent Life Changes Questionnaire. RESULTS
• As expected, women with dry OAB had significantly higher scores on the Pelvic Floor Distress Inventory and Pelvic Floor Impact Questionnaire.
• Anxiety scores were significantly higher in women with dry OAB than in controls. • No significant differences were found in sEMG measures of pelvic muscle contraction or relaxation between the two groups • There was no significant correlation between sEMG pretest resting baseline measurements and the Beck Anxiety Inventory, the Pelvic Floor Distress Inventory, the Pelvic Floor Impact Questionnaire or life stress scores among symptomatic women
CONCLUSIONS
with OAB symptoms [2]. Urinary urgency and frequency are the most common symptoms associated with OAB. While these symptoms of urgency, frequency and incontinence have been shown to significantly impact health-related quality of life, urinary urgency was found to be more bothersome than incontinence itself [2]. Unfortunately, the exact pathophysiology of dry OAB symptoms remains unclear.
Clinical observation suggests that women with dry OAB often have increased pelvic floor muscle activity and dyskinesia interfering with muscle relaxation. In the 2005 report of the ICS Clinical Assessment Group, the descriptor ‘Overactive Pelvic Floor Muscles’ was accepted as standard terminology for pelvic floor muscles that do not relax fully or contract when full relaxation is necessary [3]. There are several possible mechanisms by which overactive
• This study supports a relationship between dry OAB symptoms and anxiety that warrants further exploration. • Resting sEMG baselines were not elevated and did not support the hypothesis that women with dry OAB are unable to relax their pelvic floor muscles. KEYWORDS urogynaecology, pelvic floor, overactive bladder
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pelvic muscles may contribute to OAB symptoms. The pelvic floor muscles have a close anatomical relationship to the urethra and bladder neck. Changes in muscle function may lead to a change in the resting angle of the urethrovesical junction, which could cause irritation of the urethra or bladder neck. Alternatively, underlying neurological abnormalities may lead to pelvic floor muscle changes as well as LUTS. These changes could occur at the level of the peripheral nerves or the sacral nerve reflexes, particularly the guarding reflex. Numerous studies have linked overactive pelvic floor muscles on clinical examination and surface electromyography (sEMG) measurements to various pain syndromes including interstitial cystitis, back pain and vulvar vestibulitis [4–8]. Evidence suggests pelvic floor muscle sEMG measurements differ in women with these pain syndromes compared with asymptomatic women [9]. Furthermore, normalizing the muscle performance with sEMG biofeedback improved symptoms [9–12]. Research has also shown differences in pelvic floor muscle sEMG measurements in women with stress urinary incontinence compared with age-matched normal women [13]; however, no study to date has described pelvic muscle sEMG measurements in women with dry OAB symptoms compared with asymptomatic women to determine whether there are differences. The primary aim of the present study was to determine if pelvic floor muscle sEMG measurements differed in women with dry OAB symptoms compared with asymptomatic controls. We hypothesized that women with dry OAB would be less able to relax their pelvic floor muscles and would exhibit higher resting muscle activity and decreased ability to relax between contractions..The secondary aim of the study was to determine whether pelvic floor muscle performance was associated with anxiety scores, quality of life and life stress measures. As an exploratory analysis, we also investigated whether there were differences in anxiety scores, quality of life, and life stress measures among those women with dry OAB compared with controls. PATIENTS AND METHODS PATIENTS Women aged 18–55 years of age were recruited for this study. The study protocol
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was approved by the Institutional Review Board at the University of California, San Francisco, and all patients gave informed consent. We recruited symptomatic women reporting ≥10 voids per day and asymptomatic women reporting ≤7 voids per day. Participants were recruited from flyers posted at the UCSF Medical Center, the San Francisco State University campus, a San Francisco YMCA, and from advertisements posted in the community from November 2007 to August 2008. A designated study recruiter determined eligibility during a telephone interview and enrolled participants who met all eligibility requirements. Women who reported urinary incontinence, use of skeletal muscle relaxant medications within the past 3 months, current diuretic use, bladder infection, prior hysterectomy, 24-h fluid intake >2.5 L, congestive heart failure or any diagnosis known to potentially affect pelvic floor muscle function including vulvar vestibulitis, multiple sclerosis, type I diabetes, chronic pelvic pain, spinal stenosis and prior anti-incontinence surgery were excluded from this study. Postmenopausal women without a period for at least 6 months and pregnant women were excluded due to possible confounding of effects attributable to hormonal influences on the pelvic floor muscles. Those with psychiatric disease or those who were HIV positive were excluded. Participants were enrolled concurrently into either the ‘case’ or ‘control’ group. In order to enroll participants of similar age in each group, once 14 case and 14 control participants were enrolled, the recruiter enrolled the next 14 case and control participants, age-matching participants within a 5-year age range. We screened an additional 124 women for the study who either did not meet inclusion criteria (n = 85), were unable to attend the two required visits (n = 25), reported accidental leakage (n = 12), or were not interested in participating (n = 2).
floor muscle sEMG measurements were associated with anxiety scores, quality of life, and life stress measures. At the first visit, eligible participants completed a dipstick urine analysis to exclude a UTI, and were given a 2-day bladder diary to complete and return in a stamped envelope. Once the bladder diary was returned, study personnel reviewed the diary to confirm appropriate inclusion criteria and enrolled eligible participants in the study case or control group. Once enrolled, participants were scheduled for the second visit. At this visit, the participants underwent pelvic floor muscle testing using Pathway MR20 Dual Channel EMG System (Prometheus, Dover, NH, USA) with a vaginal sensor (Pathway vaginal sensor #6330; Prometheus) while positioned supine on the examination table with head and knees each supported by a pillow. Participants placed the sensor themselves, as instructed by the researcher. Water was used as a lubricant. Participants were initially instructed to contract and relax the pelvic floor muscles while observing the monitor but were not allowed to observe the monitor during the testing. The sEMG testing included a verbally cued 30-s baseline rest, followed by 10 repetitions of 2-s contraction and a 4-s rest, 10 repetitions of 10-s contractions and a 10-s rest, and a 30-s relaxation at completion (Time 1). After the initial sEMG testing, participants removed the sensor and completed the following questionnaires: demographics, Beck Anxiety Inventory, Pelvic Floor Distress Inventory, Pelvic Floor Impact Questionnaire and Recent Life Changes Questionnaire. Pelvic floor muscles were then re-tested with sEMG using the same testing protocol (Time 2). Participants were instructed not to discuss their bladder symptoms during the testing. The status of the recruited participants and controls was blinded to the examiner.
MEASUREMENTS DESIGN We performed a prospective case-control study to determine whether there were differences in pelvic floor muscle sEMG measurements in women with dry OAB symptoms compared with asymptomatic women. We also investigated whether pelvic
The primary outcome measures were recorded in mean microvolts (mv) of muscle activity, and included pretest and post-test resting baseline, sd of the pretest and post-test resting baseline, phasic contractions (3-s), and tonic contractions (10-s). Between-trial reliability has been
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PELVIC FLOOR MUSCLE PERFORMANCE AND ANXIETY
ANALYSIS
TABLE 1 Demographic and health characteristics comparing women with dry OAB and controls
Characteristic Age (years) Mean (SD) Education, n (%) High school or below College/college degree Graduate/professional degree General health status, n (%) Excellent Very good/good BMI Mean (SD) Current smoker, n (%) No Yes Pregnancy Mean (SD) Number of vaginal delivery, n (%) 0 1 or more Number of C-sections, n (%) 0 1 Number of UTI, n (%) 0 1 or more Number of voids per day Mean (SD) Total average fluid (oz per day) Mean (SD)
Women with dry OAB, N = 28
Controls, N = 28
37.3 (8.3)
35.3 (9.2)
2 (7.1) 19 (67.9) 7 (25.0)
0 (0.0) 19 (67.9) 9 (32.1)
P* 0.38 0.45
0.01 7 (25.0) 21 (75.0)
17 (60.7) 11 (39.3)
24.6 (3.2)
23.3 (2.8)
24 (85.7) 4 (14.3)
28 (100.0) 0 (0.0)
1.1 (1.7)
0.7 (1.2)
23 (82.1) 5 (17.9)
23 (82.1) 5 (17.9)
26 (92.9) 2 (7.1)
26 (92.9) 2 (7.1)
0.14 0.11
0.27 0.99
0.99
RESULTS
24 (85.7) 4 (14.3)
25 (89.3) 3 (10.7)
14.4 (4.8)
5.8 (1.2)
52.9 (20.9)
63.9 (32.1)
