Urinary incontinence is a significant issue, affecting one in three women worldwide. In a blog for #MyPTArticleOfTheMonth back in October 2019, women’s health physiotherapist and exercise scientist Professor Kari Bø highlighted the results of a recent high-quality trial investigating electromyography biofeedback-assisted pelvic floor muscle training. The OPAL trial has now been published in Health Technology Assessment, and we summarise the findings in this blog.
Professor Suzanne Hagen led this large-scale, multi-centre trial in the community and outpatient care setting in the United Kingdom. The trial compared electromyography biofeedback-assisted pelvic floor muscle training to pelvic floor muscle training alone for women with stress or mixed urinary incontinence who could voluntarily contract their pelvic floor muscles. Pelvic floor muscle training is the recommended first-line treatment for this patient group. The OPAL trial investigated the clinical- and cost-effectiveness of adding electromyography biofeedback (providing visual or auditory feedback of internal muscle movement) as an adjunct to muscle training.
Women aged 18 years and older who were newly presenting with stress or mixed urinary incontinence were invited to participate. A concealed and random process (with minimisation by incontinence type, centre, age and severity) was used to allocate participants into biofeedback pelvic floor muscle training or basic pelvic floor muscle training groups. All participants were offered 6 appointments over a 16-week period to receive the interventions. Home biofeedback units were provided to the biofeedback pelvic floor muscle training group. Participants in both groups were asked to complete individualised home exercise programs. The primary outcome of interest was the International Consultation on Incontinence Questionnaire Urinary Incontinence Short Form (ICIQ-UI SF) score at 2 years. This is a four-item questionnaire (total score ranging from 0 to 21, with higher scores indicating greater severity). Assessors were not blinded to the primary outcome, but were blinded for some of the secondary outcomes. Adverse events were monitored and economic data were collected. An intention-to-treat analysis was performed.
600 women were enrolled in the trial, with 300 allocated to the biofeedback pelvic floor muscle training group and 300 to basic pelvic floor muscle training. 468 participants (78%) completed the 2-year follow-up. Adherence was similar for both groups, with about 77% of participants attending at least one of the scheduled appointments and about 80% undertaking part of the home program. Participants reported being hindered by lack of time to complete the interventions. The mean ICIQ-UI SF score at 2 years was 8.2 (standard deviation 5.1) for biofeedback pelvic floor muscle training group and 8.5 (4.9) for basic pelvic floor muscle training group. There was no difference between the groups, with an adjusted mean between-difference of -0.09 (95% confidence interval -0.92 to 0.75). 23 participants (21 biofeedback pelvic floor muscle training, 2 basic pelvic floor muscle training) had an adverse event that was related or possibly related to one of the interventions. Biofeedback pelvic floor muscle training (£956) had a similar cost to basic pelvic floor muscle training (£906), with a mean between-group difference of £50 (95% confidence interval -84 to 184).
The trial concluded that adding electromyography biofeedback to pelvic floor muscle training offers no benefit over pelvic floor muscle training alone in terms of long term continence outcomes or costs. Kari Bø says: “this high-quality trial has an important message for physiotherapists treating women with urinary incontinence – pelvic floor muscle training is the key element of treatment.”
Hagen S, et al. Basic versus biofeedback mediated intensive pelvic floor muscle training for women with urinary incontinence: the OPAL RCT. Health Technol Assess 2020;24(70):1-144.
