autonomic dysfunction; bladder; Cardiovascular safety; efficacy; Mirabegron; Multiple sclerosis; Neurogenic detrusor overactivity; Spinal cord injury

Purpose To analyze cardiovascular safety of mirabegron in patients with spinal cord injury (SCI)- and multiple sclerosis (MS)-induced neurogenic detrusor overactivity (NDO) in a prospective, randomized, double-blind, placebo-controlled study. Methods Seventy-eight patients were enrolled into the study, and 66 of them were included into the final analysis. In 49 (74.2%), NDO developed due to suprasacral SCI, 17 (25.8%) suffered from NDO due to MS. Eleven patients were previously treated for hypertension and one for arrhythmia. All study participants received placebo for 2 weeks run-in period. Subsequently, eligible subjects were randomized for 4 weeks of active treatment with mirabegron 50 mg once daily (Group A; n = 32) or placebo (Group B; n = 34). Data from resting electrocardiography (ECG), 24-h ECG and blood pressure monitoring, and echocardiographic examination, were used for cardiovascular safety assessment. All reported variables were evaluated at time of randomization and at the end of the study. Longitudinal changes of variables within the groups and differences between the groups were assessed using nonparametric Kruskal-Wallis test, and p <= 0.05 was considered statistically significant. Results No statistically significant longitudinal changes were found in safety variables, except for prolongation of QT interval in placebo group (p = 0.0328) recorded by resting ECG. No significant difference between the Groups A and B, in any of the variables, was observed. A single cardiovascular study drug-related adverse event was recorded in a patient with cervical SCI (3.13%). Conclusions Our results suggest that mirabegron can be safely used in the treatment of patients with SCI- and MS-induced NDO.