Multiple Sclerosis (MS) is the most frequent autoimmune demyelinating disease of the Central Nervous System. Patients suffering from MS usually present with overactive bladder syndrome. Most common symptoms are increased frequency, urgency, incontinence and nocturia. LUTS occur on average 6 years after the onset of MS while all patients experience LUTS within a period of 10 years since the initial diagnosis. Our objective is to evaluate the efficacy and safety of treating patients with MS and LUTS using either b3 agonist (mirabegron) or anticholinergics.

This is a prospective, randomized, controlled, single center study including 91 patients with MS and LUTS. At baseline all patients underwent thorough clinical examination including neurological examination and DRE. Medical history was recorded. All patients underwent urine test, urine cultivation and abdominal ultrasound. All patients completed an urination diary (for at least 3 consecutive days) and specific questionnaires such as MusiQoL and NBSS. At second visit all patients were administered either a b3 agonist (mirabegron) or anticholinergics. More specifically, 46 patients (Group 1) received mirabegron 25mg or 50mg and 45 patients (Group 2) received solifenacin 5mg or 10mg, or fesoterodine 4mg or 8mg. The choice of the drug dosage was not random and was based on the baseline characteristics of each patient. The treatment was always carried out alongside with the MS treatment. Reevaluation was performed 3 months after the first visit. All patients underwent the same clinical and imaging tests that were carried out at first visit. A statistical analysis was performed in both groups using the t-test.

We compared several clinical and imaging parameters (scores of the 2 questionnaires, potential pelvic or calyceal dilatations, increased urine residual volume, infection, Qmax flow rate) between the two groups at first visit and 3 months after treatment. In both groups improvement in LUTS was recorded in most of the tested parameters. Statistical significant difference from baseline evaluation up to reevaluation was recorded in terms of urine infection (p value≤0.01), MusiQoL score (p value <0.001), NBSS score (p value<0.05), dairy urgency episodes (p value <0.001), dairy number of urinations (p value <0.001) and urination volume (p value <0.001) in both groups. Nevertheless, comparison between Group 1 and Group 2 revealed no statistical difference. No patients discontinued medications due to side-effects.

All patients in both groups showed a statistical significant improvement in most of the tested parameters, from baseline up to reevaluation. There was no difference in symptoms improvement in the mirabegron group compared to the anticholinergic group.
Thus, all drugs tested presented similar efficacy and safety.

All MS patients receiving either mirabegron or antimuscarinic therapy for LUTS showed an improvement. No statistical difference was noted between the two groups in all the tested parameters.