Multiple sclerosis (MS), affecting over 100,000 people in the United Kingdom (UK), is the commonest cause of neurological disability in young people (1,2).  Its worldwide prevalence is increasing (2).  Urinary symptoms are reported by up to 99% of MS patients (3).  Urinary frequency is reported by 25-99%, urgency by 32-86%, urgency urinary incontinence (UUI) by 19-80% and urinary retention by 8.3-73.8% of patients(3).  Studies that have investigated urodynamics (UDS) findings in patients with MS have found detrusor overactivity (DO) is present in 22.5-99%, detrusor underactivity (DU) in 0-40%, loss of compliance in 2-10.3% and detrusor-sphincter-dyssynergia (DSD) in 5-82%(3).  

The UK consensus on the management of the bladder in MS provides algorithms to guide the management of urinary symptoms. The initial management involves testing for urinary tract infection (UTI) and starting intermittent self-catheterisation (ISC) if there is a post-void residual volume of over 100ml.  Following this, anticholinergic medications are recommended.  Since the publication of this document, Mirabegron, a beta-3 agonist, has also been used as an alternative or in addition to anticholinergic medication.  If the patient has refractory overactive bladder (OAB) despite oral medications, urodynamic investigations are recommended in patients who wish to undergo further interventions.  The consensus does acknowledge that upper tract dilatation is uncommon in patients with MS and that the ‘benefit of urodynamics does not invariably warrant the intrusive nature of the study and the risks associated’. This is in contrast to a French guideline proposal, published in 2007 which recommends UDS in any MS patient with urinary symptoms.  The 2023 European association of urology (EAU) guidelines on neuro-urology recommend video-urodynamics (VUDS) for baseline assessment of all neuro-urology patients and do not make specific recommendations for when to do UDS in MS patients.  The 2012 national institute for healthcare and care excellence (NICE) guidelines on urinary incontinence in neurological disease do not recommend urodynamics as a baseline investigation for MS patients as they are at low risk for upper tract deterioration.  The NICE guidelines do however recommend UDS prior to surgical intervention including intra-detrusor botulinum toxin (BTX-A) injections for refractory OAB.

The UK consensus on the management of the bladder in MS, the 2012 NICE guidelines on urinary incontinence in neurological disease and the 2023 EAU guidelines all recommend intra-detrusor BTX-A injections in patients who do not respond sufficiently or do not tolerate anti-muscarinic mediation.  Sacral neuromodulation (SNM) is recommended in patients who do not respond sufficiently to BTX-A by the 2009 UK consensus.  The 2023 EAU guidelines mention SNM but do not make recommendations for its use in patients with neurological disease owing to the lack of randomised trials.  SNM is not mentioned by the 2012 NICE guidelines.

This study aims to establish the current role of urodynamics in the treatment pathway of a patient with MS related neurogenic lower urinary tract dysfunction (NLUTD).

Patients with MS who were Botox-naïve and had undergone standard or VUDS were identified from prospectively maintained databases in UK hospitals.  Data was collected and analysed using Microsoft Excel version 16.83.  The study was registered as an audit (reference NFW003). Urodynamic findings are shown in table 2.

157 patients were identified from 7 UK departments.  VUDS were performed in 94 (84.7%) females and 40 (87.0%) males. Standard UDS were performed in 17 (15.3%) females and 6 (13.0%) males.  Baseline patient data at the time of urodynamics is shown in table 1.  Urodynamic findings are shown in table 2.

Of the 94 women and 36 men reporting pure OAB, 66 (70.2%) women and 30 (83.3%) men showed NDO or poor compliance on urodynamics. Of the 39 women reporting SUI, 22 (56.4%) demonstrated urodynamic SUI and 26 (66.7%) showed NDO.  Of the 6 (5.41%) women who reported pure SUI, 5 (83.3%) showed urodynamic SUI without NDO and 1 (16.7%) showed NDO.  Following urodynamics, 61 (72.6%) women and 25 (78.1%) men were offered oral medication, topical treatment or non-medical treatment such as pelvic floor physiotherapy, fluid and lifestyle advice; 30 (30.9%) women and 7 (18.9%) men were advised to start ISC; 16 (19.0%) women and 4 (12.5%) men were offered intra-vesical BTX-A; 2 (2.4%) women were offered surgery for SUI and 1 (3.1%) man was offered surgery for bladder outflow obstruction.

Patients with MS related NLUTD undergoing urodynamics mainly report storage symptoms and nearly half of the female patients reported SUI.  Only 5.4% of women reported pure SUI. Over half of patients underwent UDS before they have tried any medications for OAB which is earlier than most guidelines recommend. No females demonstrated ureteric reflux on VUDS, less than 1% of women had end fill pressures over 40cmH20 though approximately 10% had poor compliance.  Approximately ¾ of patients were offered conservative or oral medication following urodynamics.  Very few MS patients underwent surgery for bladder outflow obstruction or stress incontinence following UDS.

UDS provides very helpful information on the underlying pathophysiology of patients with MS related NLUTD.  Many patients had their urodynamics earlier in their pathway than most guidelines recommend potentially delaying non-invasive treatment.  The role of fluoroscopy at the time of urodynamics in MS patients will need further evaluation but preliminary data suggests that fluoroscopy is not required in MS patients with pure OAB storage symptoms and no post-void residuals.

Thompson AJ, Baranzini SE, Geurts J, Hemmer B, Ciccarelli O, 2018, ‘Multiple Sclerosis’, Lancet, 391:1622-36
Collaborators GBDMS, 2019, ‘Global, regional, and national burden of multiple sclerosis 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016’, Lancet Neurol, 18:269-85
de Seze M, Ruffion A, Denys P, Joseph PA, Perrouin-Verbe B, Genulf, 2007, ‘The neurogenic bladder in multiple sclerosis: review of the literative and proposal of management guidelines, Mult Scler, 13:915-28