Use of a symptom-based questionnaire to screen for the presence of significant voiding dysfunction in patients with multiple sclerosis and lower urinary tract symptoms: a pilot study

INTRODUCTION: Lower urinary tract dysfunction is common in people with multiple sclerosis, leading to overactive bladder symptoms, voiding difficulties or a combination. First-line medications for overactive bladder symptoms are effective. Current guidelines recommend measuring post-void residual volume (PVR) before commencing these treatments, as they can potentially exacerbate voiding difficulties in those with significant underlying voiding dysfunction (pre-treatment PVR > 100 ml). However, facilities to do so are not readily available to all clinicians, potentially delaying effective therapy. AIMS: To conduct a pilot study investigating the association between lower urinary tract symptoms and PVR volume in people with multiple sclerosis using a validated questionnaire and to determine if questionnaire scores can be used to exclude a significantly elevated (> 100 ml) PVR volume. METHODS: Patients with multiple sclerosis referred to a tertiary hospital uro-neurology service completed the Urinary Symptom Profile questionnaire and underwent PVR measurement by bladder ultrasound. A ratio of the questionnaire low stream score/total score was calculated to standardise the relative degree of voiding symptoms compared to overall lower urinary tract symptoms. RESULTS: Of 40 patients (29 females, mean age 50 years), 30% had an elevated PVR volume. PVR volume was correlated with low stream score and ratio of low stream/total score. A cut-off of > 0.15 for low stream/total score ratio had 92% sensitivity and 71% specificity in predicting an elevated PVR volume. CONCLUSION: A symptom-based questionnaire maybe a useful screening tool to distinguish patients in whom PVR measurement is required from those who could safely start on treatment for overactive bladder symptoms.