Mapping the Evidence on Peripheral Magnetic Stimulation for Urinary Incontinence: A Systematic Umbrella Review

Peripheral magnetic stimulation therapy (PMST) has emerged as a promising, noninvasive alternative to the traditional treatment approaches for urinary incontinence (UI). This systematic umbrella review aimed to synthesize the available secondary literature to provide a definitive, high-level overview of PMST's efficacy, safety parameters, and clinical utility.

A systematic overview was conducted following the Cochrane Handbook and Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guidelines. An a priori protocol was registered via the International Prospective Register of Systematic Reviews (PROSPERO), and systematic literature screening was performed using Rayyan. The Joanna Briggs Institute critical appraisal checklist was utilized to evaluate the methodological quality of the included systematic reviews and meta-analyses. Primary study overlap across the portfolio was structurally mapped and mathematically quantified using the Corrected Covered Area (CCA) formula. The certainty of the synthesized evidence across key clinical end points was evaluated using the narrative GRADE framework. Data extraction was restricted strictly to the systematic review components.

Fifteen systematic reviews and meta-analyses were included. Citation matrix analysis revealed a Corrected Covered Area (CCA) of 3.64%, demonstrating a slight overlap and confirming that the synthesized secondary evidence base is non-redundant. Synthesized data revealed a consistent frequency-specific pattern across the included reviews, whereby higher-frequency protocols (35-50 Hz) were most commonly applied to pelvic floor muscle recruitment in stress urinary incontinence, whereas lower-frequency protocols (10-15 Hz) were more frequently used for urgency urinary incontinence and overactive bladder. However, these observations represent prevailing treatment approaches rather than a validated therapeutic paradigm. Relative to sham/placebo configurations, PMST yielded statistically and clinically significant improvements in objective leakage metrics (pad tests) and subjective symptom indices (ICIQ-SF, Health-Related Quality of Life). Safety data demonstrated a remarkable tolerability profile, with adverse events limited to mild, transient, and self-limiting symptoms (eg, local tingling, mild soreness, or increased stool frequency), with no severe complications reported. Methodological quality across the evidence base was highly polarized, with 25% of reviews scoring high and the remainder classified as moderate or low due to deficits in comprehensive database search strings or formal primary study risk-of-bias monitoring.

PMST appears to be a safe and potentially effective therapeutic option for the management of urinary incontinence and may be considered either as a standalone treatment or as an adjunct to conventional physical therapy. However, the interpretation and clinical application of these findings are limited by considerable heterogeneity in stimulation protocols, patient populations, and outcome measures; variable methodological quality among the included reviews; and the scarcity of long-term follow-up data exceeding six months.