The main objective of the study is to determine the rate of patients who stop baclofen due to an adverse event (AE) in the first year of treatment.The BACLOPHONE study also aims to determine which types of AEs and serious AEs are actually liable to baclofen, and which other types are more likely the consequence of confounding factors, e.g., concomitant alcohol, psychotropic medications or substance uses, and comorbidities.