# Urinary dysfunction in myasthenia Gravis: a cross-sectional case-control study

## TL;DR

This study finds that urinary issues like incontinence are more common in myasthenia gravis patients compared to controls, with disease severity and age of onset influencing these symptoms.

## Contribution

The study is the first to systematically assess urinary dysfunction in a large MG cohort using standardized questionnaires and identify MG severity as a predictor of urinary incontinence.

## Key findings

- MG patients had a 52.3% prevalence of urinary incontinence compared to 12.2% in controls.
- LOMG patients showed the highest UI prevalence and fastest progression to UI symptoms.
- MG-ADL score independently predicted urinary incontinence (OR 2.38).

## Abstract

Myasthenia gravis (MG) is a disorder of neuromuscular transmission that primarily affects skeletal muscles, leading to cranial, truncal, and limb weakness. While motor symptoms are well documented, the prevalence and clinical significance of urinary dysfunction particularly urinary incontinence (UI) and overactive bladder (OAB) symptoms remain underexplored in MG, with previous reports limited to small cohorts.

In this study, 86 MG patients and 90 age- and sex-matched inpatient controls were evaluated. All participants completed the International Consultation on Incontinence Questionnaire-Short Form (ICIQ-UI SF) and the Overactive Bladder Symptom Score (OABSS). MG severity was assessed using the Myasthenia Gravis Activities of Daily Living (MG-ADL) scale. MG patients were further categorized into early-onset (EOMG), late-onset (LOMG), and very late-onset (VLOMG) subgroups. Logistic regression identified predictors of UI, and Kaplan–Meier analysis was used to evaluate time to first UI symptoms.

MG patients had significantly higher prevalence of UI symptoms (ICIQ-UI SF ≥ 6 in 52.3% vs. 12.2% in controls; p < 0.001). LOMG patients exhibited the highest UI prevalence (63.2%) and progressed most rapidly to UI, while EOMG patients had the latest onset. OAB symptoms were also more prominent in MG, marked by higher OABSS and increased urgency. MG-ADL score independently predicted UI (OR 2.38; 95% CI 1.04–5.46; p = 0.041).

UI and OAB symptoms are more common in MG patients than in controls. MG-ADL score is an independent predictor of UI, and age at disease onset may influence the timing of UI development. Early identification and intervention may improve patient outcomes.

The online version contains supplementary material available at 10.1007/s10072-025-08588-8.