Hypothesis / aims of study
Lower urinary tract symptoms (LUTS), including urinary frequency, urgency, urgency urinary incontinence and nocturia, affect 27–85% of people with Parkinson’s disease (PD) and have a negative impact on quality of life.
Small studies suggest that conservative therapy including bladder training, biofeedback, and pelvic floor muscle exercises may reduce LUTS in PD, but robust evidence is lacking[1].
Electrostimulation is promising for the treatment of LUTS in the general population, but its efficacy in PD and optimal parameters remain unclear[2].
This study aimed to evaluate the effectiveness of different electrostimulation parameters, combined with conservative therapy, in reducing LUTS in PD.
Study design, materials and methods
We conducted a single-blind randomized controlled trial(RCT) [3]. Adults, ≥ 18 years with PD and self-reported LUTS, who were able to complete online questionnaires and attend pelvic physical therapy sessions, were included. Exclusion criteria comprised pacemaker or Deep Brain Stimulation as well as pelvic surgery or prior conservative therapy within the past year.
Participants were randomized (1:1:1), stratified by gender, into three groups differing in electrostimulation parameters: group 1: 200µs/20Hz continue; group 2: 1000µs/8Hz continue, and group 3 (sham): 200µs/100Hz intermittent.
All participants received the same conservative therapy program, consisting of bladder training, pelvic floor muscle exercise assisted biofeedback (using an intra-vaginal or anal probe) and at least 6 sessions of 20 minutes electrostimulation, delivered over eight sessions within twelve weeks.
Primary outcomes were between-group differences in LUTS reduction, assessed using the International Prostate Symptom Score (IPSS, range 0-35).
Secondary outcome was the Global Perceived Effect, used post treatment to assess perceived change in complaints and patient satisfaction, on 7-point Likert-scale.
Sample size calculation indicated that 150 participants were required to detect a clinically important difference of 4,2 points in IPSS between each intervention groups (1, 2) and sham (3), with 80% power, two-sided α=0.05, and 20% dropout. Analyses followed the intention-to-treat-principle.
Between group differences were assessed using an overall Wald-test, adjusted for gender, followed by pairwise comparisons using t-tests with Dunnett adjustment for multiple testing. In an additional analysis, pre- to post-treatment change across all participants was explored using a paired t-test.
Results
A total of 138 participants, median age of 69 years and a PD median duration of four years were included and 131(95%) participants were analyzed.
There were no significant between-group differences in IPSS scores (overall Wald-test, p=0.71). Pairwise comparisons showed no significant differences between either electrostimulation group and the sham. These findings remained non-significant after Dunnett adjustment (group 1 vs sham p=0.98; group 2 vs sham p= 0.60).
In the additional analysis, pooling all participants, IPSS scores improved significantly from baseline to post-treatment, with a clinically important mean reduction of 4.4 points (95% CI 3.6-5.2) (Figure 1).
The median Global Perceived Effect was 3, corresponding to slight improvement, and was 2 for satisfaction, corresponding to mostly satisfied.
Interpretation of results
This is the first RCT investigating the combination of electrostimulation and conservative therapy for LUTS in people with PD. None of the electrostimulation parameters showed an added benefit over sham stimulation. However, all participants demonstrated clinically meaningful improvement in LUTS from baseline to post treatment. The high level of compliance suggests strong acceptability of the intervention, supporting its use as a treatment option for LUTS in PD. Health care professionals should integrate conservative therapy as a treatment option and clear implementation strategies are needed to facilitate its effective adoption in routine practice.