Do stages of menopause affect the outcomes of pelvic floor muscle training?

Tosum OC, Mutle EK, Tosun G, Ergenoglu AM, Yeniel AO, Malkoc M, Askar N, Itil IM.  Menopause.  2014; 22(2): 1-10. DOI: 10.1097/gme.0000000000000278.

Ann Dunbar PT, DPT, MS, WCS

September 10, 2014

Introduction: UI is a common complaint. Numerous hormonal changes occur during the menopause transition.  A relationship exists between hormone levels and the urinary system.  A relationship also exists between hormonal changes and muscle mass including decreases in the ratio of connective tissues to muscle fibrils in the urethral stricture and pelvic floor.  Pelvic floor exercise is recommended as the first line of treatment for stress urinary incontinence (SUI).  Little research exists on the impact of menopausal changes on PFMT.

Primary Aim:  (1) Determine impact of pelvic floor muscle training (PFMT) on increases in PFM strength during different stages of menopause.

Subjects: 122 women with stress and mixed urinary incontinence; separated into 3 groups according to stage of menopause

Study Design:  Prospective controlled clinical trial

Methods:

Definition: STRAW Staging System:  First standardized classification guidelines for reproductive aging (7/2001). It is anchored on the final menstrual period.  Consists of 7 stages where Stages -5 to -3 represent the reproductive years, Stages -2 to -1 represent the menopausal transition, Stages +1 to +2 represent early and late postmenopause respectively.

Participants:  Inclusion Criteria: UI dx by UroGyn using urodynamics analysis. Subject Exclusion Criteria: listed in study. Also excluded women who had undergone pelvic floor muscle training PFMT at PT clinic within past 2 years, women whose pelvic floor muscle (PFM) strength was 0 to 1. 

Participants placed into 1 of 3 Groups (based on final menstrual period or menstrual irregularity and/or FSH level): See Figure 1

• Group 1 (G1): Women in late reproductive age with STRAW Stage -3 and in early menstrual transition experiencing variable cycle lengths and STRAW Stage -2 and where the length of consecutive cycle lengths differ by more than 7 days.
• Group 2 (G2): Women STRAW Stage -1 who went through late menopausal transition with at least 1 intermenstrual interval of 60 days or more regardless of FSH levels and STRAW Stage +1 who had final menstrual bleeding between 2 and 5 years ago.
• Group 3 (G3): Women STRAW +2 who had their final menstrual bleeding more than 5 years ago.

Other Group Determinants: Authors discuss state of research predicting menopausal stage. FSH level higher than 40 IU/L is independent marker of late menopausal transition though has not been found to be as predictive as menstrual bleeding markers (eg amenorrhea for 60 days or more). Therefore the following questions were used to determine G1 participants. Those answering ‘yes’ to the following were not included in G1: “Do you have 2 or more missed menstrual cycles?” and “Have you ever missed your menstrual cycle for 60 days of more?” Next participants were asked “Has there been any change in the length of your menstrual cycle in the last year?” Participants answering ‘yes’ and who also were determined to have increased FSH levels were included in G1.  Participants for G2 and G3 were asked,”

 “When did you have menstrual bleeding for the last time?”

Procedures:  Data collected at initiation: age, # pregnancies and delivery type, age at first delivery, weight of heaviest newborn, menarche, duration of UI, BMI, duration of menses.

Assessment of PFMs:  used PERFECT Scheme, Brink Scale, perineometry, transabdominal US, pad test, and stop test. Assessments done by same PT and GYN before and after PFMT who were blinded to rx or rx sequence.

PFM Strength Evaluation:  Completed by experienced pelvic floor PT. Computer-generated randomization used for determining order of following tests. All were perfomed on same day with 30 minute rest period after each strength test. All performed 3 times; mean calculated from these 3 trials.

• PERFECT Scheme:  Results of evaluation were recorded and also used as an exercise program.
• Brink Scale assesses (1) muscle force or vaginal pressure; (2) vertical displacement or elevation of examiner’s finger; (3) Duration of contraction. See article for details of scoring. Total range 3 to 12.
• Perineometer: Vaginal squeeze pressure assessed immediately after emptying bladder. Measurement procedures for use of perineometer were standardized and are reported in the article. Three trials completed.
• Transabdominal US: Used to measure bladder base movement during a PFM contraction. Central portion of bladder base first measured at rest.  Then given instruction to “draw in and lift PFM” and hold while breathing and probe was immediately placed, bladder base viewed and marked at point of maximal displacement. Three trials completed.

Stop Test: Recorded participant’s effort to stop or slow urine stream midstream having a full bladder.

One-hour Pad Test: performed on protocol established by ICS.

Above measurements have been reported to give scores with reasonable test-retest reliability, interrater reliability, and validity.

Blood Samples: Protocol described in article.

Treatment Protocol:  All participants received individualized PFM exercises.  First 2 weeks of training program including PFM function and localization, advice on bladder hygiene, all participants received same information.  First 2 visits women learned to accurately contract their PFM with word cues, without accessory m contraction and with palpation of perineal body.  PFM learning focused on improving awareness of the contraction factoring in each woman’s loss of proprioception and strength as well as her ‘tolerance’.  PFM training also included training in proper posture. Each participant’s exercise program was prepared using PERFECT Scheme data. All were given written instructions.  At each follow up PT session, exercises were reviewed (included positioning, number of repetitions of slow and fast contractions, duration of rest and number of repetitions in a day and week).  Visits attended during weeks 4,8,10, and 12 included check of PFM function by vaginal assessment according to PERFECT Scheme as well as by palpation of perineal body.   At each visit, women were also asked about changes in sx as well as adherence to home exercises. Progress was reviewed and exercises were progressed according to the PERFECT Scheme. Women were instructed in “The Knack” and advised to use in ADLs including coughing, sneezing and lifting. All participants were required to keep record of exercises. Interventions with same PT were 30 minutes in duration, 3 times/wk during the 12 week period.

Statistical Analysis:  Descriptive analysis presented as means with SD. One-way analysis of variance used to compare parameters among groups G1, G2, G3. To assess homogeneity of variances, the Levene test was used. Authors considered value of P<0 .05="" i="" observed.="" overall="" paired-sample="" s="" significance="" significant.="" statistically="" style="mso-bidi-font-style: normal;" test="" tukey="" used="" was="" when="">t

test was used when comparing pre- and posttraining values within groups. Correlation between pre- and posttraining strength values were determined using Spearman correlation analysis (took average of 3 measurements while also analyzing results of US and perineometry). Calculations for power of 80% revealed minimal sample size of 27.

Results

For baseline characteristics amongst groups, see Tables 1 and 2. Of all parameters only age, number of pregnancies, menarche, and stop-test values were significantly different between groups.

For this study, 156 women were selected but 33 eliminated due to exclusion criteria. Each group initially had 41 participants but 20 dropped out (16.4% dropout rate; reasons included changes in work conditions and other health problems).

Group characteristics: Age range of G1 was 40 to 52; G2 was 43 to 58; G3 was 57 to 70 years. For all participants, 51 had SUI and 52 had MUI. For G3, 68.4% of these women had MUI and SUI occurred twice as often in this group.

PFM Function Results: After 12 week study period, PERFECT Scheme, Brink scale, perineometry and US values were all significantly increased for G1, G2, G3. Stop test and 1-hour pad test were significantly decreased. PFM power values 3 and greater increased pre/post as follows: G1 33.6% to 92.6%; G2 40.7% to 84.4%; G3 23.3% to 80%. Note that numbers for G2 and G3 (p.7) are incorrect. Other typographical errors occur on this page as well (Brink “displacement” not “replacement”).

Discussion

• Before treatment, there were no differences among groups in the parameters evaluating PFM strength.  After treatment, power, repetition, speed, Brink vertical displacement and stop test demonstrate statistically significant differences. Authors state that this ‘shows that the increases in strength achieved with PFM training differ at different stages of menopause.’
• Results demonstrate that strength gains can be made at all stages of menopause however, strength gains did vary with stage: greatest increases were in G1 (late reproductive and early menopausal transition) and lowest strength gains were in G2 (late menopausal transition and early menopause).
• Though women who received or were receiving estrogen therapy were not included in this study, research is suggesting a benefit for reducing UI when combined with PFMT.
• Authors state PFMT program was designed to help women maximize their PFM strength.  (recommended 36 sessions over 12 weeks for a strengthening protocol).
• Posture addressed in initial phase of study because ‘abnormal posture increase weight on the pelvic floor structures.’ Per Britnel et all, 2005
• Authors discuss previous studies demonstrating benefits of PFMT with decreasing symptoms. Prior research also demonstrated urine leakage increases through the duration of menopause, supported by this study as well.
• Findings from this study suggest that hormonal patterns do affect muscle strengthening, specifically that women in the first 5 years after their final menstrual period have a decreased response to PFMT. Authors note however, that additional research is needed to further evaluate this observation.

Limitations:

Quality of life and symptoms were not assessed.  

STRAW 7 system the authors consider a limitation since the system has now been updated to STRAW 10.

 

Clinical Application

1)       These findings suggest that stage of menopause affects rate of PFM strength increase.  How does this finding compare with your clinical experience?

2)       Do you agree with the methods used to assess PFM strength?  Do you use the Brink Scale?

3)       Authors excluded women with strength 0 to 1 stating that “electrotherapy methods must be used for cases with muscle strength of around 0 to 1.”  Is this consistent with your practice?

4)       Participants in this study were taught “that improper posture could damage the pelvic floor.”   Do you agree?  How do you include posture education in your program?

5)       The frequency and duration of this study is not reasonable (36 visits in 3 months).  What alternatives can we substantiate with evidence?