Hypothesis / aims of study
The International Continence Society (ICS) defines a pelvic floor muscle (PFM) normal contractile function as the ability to constrict and do an inward movement of the pelvic openings (1). Studies have shown that more than 30% of women do not contract their PFM correctly at a first consultation, even after verbal instruction (2). Most of them contract other muscles like the gluteal, adductor or abdominal instead of the PFM, others stop breathing or try to exaggerate inspiration instead of doing a contraction and others push in a downward perineum movement. Pelvic floor muscle training (PFMT) has been recommended as the first line treatment for urinary incontinence (UI) due to the important role of the PFM in the continence mechanism (3). However, this therapeutic approach might not be a viable option for all women with UI considering that many of them may not able to contract the pelvic floor correctly at a first moment. On the other hand, even though women can perform an appropriate contraction, other important muscular aspects that could be involved in UI sometimes are ignored such as endurance, coordination, relaxation or the combination of these parameters. Therefore, the aim of this study is to know how many women with UI are unable to contract their PFM in a first assessment carried out at a Pelvic Floor Physiotherapy Outpatient Clinic of a teaching hospital and to analyze if this is related to worst UI symptoms and worst impact in quality of life. Considering all of has been published about the role of PFM in the continence mechanism, we hypothesized that the inability to contract the PFM would be associated with UI severity and worsening in quality of life.
Study design, materials and methods
This is a cross-sectional study from medical records of women with UI who were referred to pelvic floor physical therapy after underwent a gynecological evaluation in a public teaching hospital between May 2013 to December 2019. Records included demographic data, PFMs strength through Modified Oxford Scale (MOS) and the final score of the International Consultation on Incontinence Questionnaire Short Form (ICIQ-SF) from a baseline assessment. The MOS is a standardize method to assess PFM strength during a maximal voluntary contraction (MVC) by digital vaginal palpation. This scale ranges from 0 to 5: grade 0 is when there is no discernible muscle contraction; grade 1 is a flicker or pulsation felt under the examiner's finger; a grade 2 detects a contraction but without any discernible lift; in a grade 3 the muscle contraction is further enhanced and characterized by the elevation of the posterior vaginal wall; grade 4 is a good contraction with the capable of elevating the posterior vaginal wall against resistance by digital pressure applied to the posterior vaginal wall and in the grade 5 the examining finger is squeezed and drawn into the vagina against a strong resistance applied to the posterior vaginal wall. The ICIQ-SF is a validate questionnaire developed for assessing the prevalence, severity, impact on quality of life and type of UI. There are three scored questions and a visual analogue scale ranging from 0 to 10 on how much does leaking urine interfere in the patient everyday life. The overall score ranges from 0 to 21, with greater values indicating increased severity of UI symptoms. For this analysis, women were divided in two groups: those who were not able to voluntary perform a PFM contraction (grade 0 and 1 in the MOS) and those who were able to voluntary contract the PFM (grade ≥2 in the MOS). All statistical analyses were conducted using Statistical Package for the Social Sciences (SPSS) version 21 and group differences were tested using univariate t-tests. Incomplete data records were excluded from the analysis.
Results
During the considered period, 617 medical records were found of women with UI who were referred by the gynecology team to a physiotherapeutic evaluation in a public teaching hospital. Of these, 111 were excluded due to incomplete data, leaving 506 records for the final analysis. The mean age was 57.38 (±11.29) years, 36.4% were not able to voluntary perform a correct MVC of the PFM (grade 0 and 1 in the MOS) after verbal command and proprioceptive digital stimulus and the most prevalent type of UI was the mixed UI in 64.6% of the cases. Characterization of the sample are presented in Table 1. As it is shown in Table 2, there is no significant difference between the variables analyzed when groups are compared, including the final score of the ICIQ-SF. This shows that regardless of whether they know how to contract the PFM or not, both groups had the same degree of UI symptoms classified as severe and the same impact in quality of life.
Interpretation of results
Women with the capacity of performing a PFM contraction appears to have the same severity of UI symptoms and impact in quality of life as women without this condition. This reinforces that other PFM aspects are important in the mechanism of continence like resistance, coordination and relaxation. Other systems also play an important role in this context, such as connective and support tissues and other aspects like hormone conditions, overweight and obesity, type of UI and daily life habits. Despite that, the fact that 36.4% of these women were not able to voluntarily contract the PFM corroborates with other studies (2) and draws our attention to the importance of evaluating the correct execution of this contraction before just orienting exercises for all women with UI. The absence of objective measures to evaluate the severity of UI, as the pad-test, is a limitation of this study. Although the ICIQ-SF is a validated questionnaire for the assessment of UI symptoms and their impact on quality of life, this tool considers only the patient's perspective regarding her clinical condition. This type of evaluation has become relevant in research and clinical practice, but the combination of objective measures would make the results more consistent. In addition, only women with UI were evaluated. It would be interesting to evaluate and compare the data also with a group of women without pelvic floor dysfunction.