Research Studies
Biofeedback for the treatment of female pelvic floor muscle dysfunction: a systematic review and meta-analysis.
Fitz FF, Resende AP, Stüpp L, Sartori MG, Girão MJ, Castro RA. Int Urogynecol J 2012; 23: 1495-1516.
Why they did the study
Biofeedback has been widely used as an adjunctive treatment modality with pelvic floor muscle training for female pelvic floor dysfunctions. However, the effectiveness of this therapeutic approach remains poorly understood with some studies suggesting that adding biofeedback offers no advantage over muscle training alone. The objective of this review was to summarize the available evidence from randomized controlled trials assessing the effectiveness of biofeedback when combined with pelvic floor muscle training as a conservative treatment option for female pelvic floor dysfunctions.
How they did it
This was a meta-analysis of randomized controlled trials. Biofeedback [BF] was defined as a therapeutic intervention for pelvic floor dysfunctions in women that involves receiving visual or auditory feedback from pelvic floor muscle activity using a tool (surface electromyography or manometry). A computerized electronic advanced search was performed to identify relevant studies using specific databases: MEDLINE (1966 to March 2011), LILACS (1993 to March 2011), PubMed (1974 to March 2011) and PEDro (1985 to March 2011). Terms for BF and pelvic floor muscle dysfunction were included in the search by use of MeSH (Medical Subject Headings of the National Library of Medicine) and these 2 keywords related to the domains of randomized controlled trials were used for each database. Studies written in English were only included. One reviewer screened the search results for potentially eligible studies, while the other two reviewers independently reviewed the screened articles for eligibility. A fourth independent reviewer resolved any disagreement concerning the inclusion of trials.
Studies were eligible for inclusion if they were randomized controlled trials comparing pelvic floor muscle training [PFMT] with BF to placebo or no treatment, PFMT without BF, electrical stimulation or any other conservative treatment for women with pelvic floor muscle dysfunctions. Trials were considered to have evaluated PFMT with BF when the treatment included both treatment approaches alone without involving other therapeutic options whether for stress urinary incontinence, overactive bladder, fecal incontinence, anal incontinence, constipation or sexual dysfunction, and at least one of the groups received the treatment. Studies were included only if one of the following outcome measures were reported: symptoms, quality of life or strength and/or pelvic floor muscle function.
The methodological quality of the trials was assessed using the PEDro scale from the PEDro database. The assessment of the quality of trials in the PEDro database was performed by two independent raters and disagreements were resolved by a third rater. Outcome measures were included for short-term (less than 3 months after randomization), intermediate-term (at least 3 months but less than 6 months after randomization) and long-term (12 months or more after randomization) follow-up evaluations. Results were pooled when trials were considered sufficiently homogeneous with respect to participant characteristics, interventions and outcomes. When trials were statistically heterogeneous, estimates of pooled effects were obtained by use of a random effects model.
What they found
The electronic database search resulted in a total of 404 articles. Of these, 67 articles were selected as potentially eligible on the basis of their title and abstract and 45 were excluded from analysis. A total of 22 studies were thus included in this review. Of these, 15 studies addressed urinary dysfunction (14 stress urinary incontinence and/or mixed urinary incontinence and 1 overactive bladder), 3 studies related to anorectal dysfunction and 4 evaluated sexual dysfunction.
The methodological quality assessment by the PEDro scale revealed a median score for all studies. The flaws were lack of concealed allocation, comparability of study groups at baseline and blinding of subjects, therapist and assessors, inadequate follow-up and not including intention-to-treat analyses.
The pooled results revealed no statistically significant differences between treatment groups for different types of pelvic floor dysfunctions. The control arm intervention included PFMT alone, electrical stimulation, vaginal cone, bladder training, congnitive behavioural therapy, lignocaine gel and no treatment.
Why it matters
Female pelvic floor dysfunction(s) is a descriptive term for a wide variety of prevalent and functional clinical disorders affecting the different compartments of the pelvic floor in women. The anterior compartment is related to sexual and urinary function with urinary incontinence, pelvic organ prolapse and sexual dysfunction as the most common abnormalities. The posterior compartment is related to colorectal function and the most common dysfunctions are fecal incontinence and constipation.
Pelvic floor muscle training is used as a conservative treatment to prevent and treat pelvic floor dysfunctions in women by improving the function and strength of the pelvic floor muscles. Biofeedback is an adjunctive technique to PFMT in which information about a normal physiological process is presented to the patient via subconscious methods and/or via the therapist offering a visual, auditory, or tactile cue. This method has been used to teach patients awareness of their muscle functioning in order to improve and motivate the patient’s efforts during PFMT. Patient compliance is considered important in PFMT as treatment effects are partially dependent on this. The efficacy of therapeutic exercises can only be established when patients adhere to the exercise regimen and this is improved when they receive positive feedback. Despite the theoretical advantages of BF, some studies have shown that there is no therapeutic benefit from adding BF to PFMT as opposed to performing conventional PFMT only. As a result, the indications and effectiveness of using BF in the treatment of female pelvic floor dysfunctions remain unknown.
This review does not provide clear data to guide clinical practice because of the poor quality of studies included. Furthermore, there is a potential publication bias because non-English language studies were excluded. Reporting bias is also possible because various outcomes have been used to measure the same treatment effect while the correlation between treatment outcome measures is known to be low. The patient populations studied were heterogeneous with an additional confounding effect of unknown demographic variables such as parity, menopausal status, age and body weight on the results of treatment. Observer outcome bias, short follow-up and break of concealment allocation are further methodological problems.
Next question
It is clear that further trials are urgently needed to investigate whether adding BF to PFMT is more effective than PFMT alone in the treatment of women with different pelvic floor dysfunctions. More importantly, the group of women who will benefit the most from combined treatment should be identified and the precise therapeutic gain determined in order to support clinical decisions with robust scientific evidence. Future research should be well-designed and adequately powered to address the methodological limitations of studies reported so far in the literature about the use of BF in women with pelvic floor dysfunctions. Although adverse effects have not been reported with BF, it must be remembered that adding non-effective treatment regimes incurs a cost to the health care system.
