12 msfocusmagazine.org Health & Wellness Progressive MS: Your Questions Answered by Augusto Miravalle, MD, FAAN When I was invited to write an article about progressive MS, the first thought that came to mind was: what can I write that will be helpful to our patients and their family members?There is an abundance of literature about progressive MS, presenting eloquent descriptionsofthediseaseprocess,thecomplex immunology that is thought to cause this disease, and updates on various therapies available for its treatment. However the more I thought about this topic, the more I realized that this information might still be presented in ways that does not fully answer the most commonquestionsmypatients often have about progressive MS. For that reason, I decided to address the most common questions I get asked in clinic, hoping that this could help fill some of those knowledge gaps. Let’s start with a basic one: What is progressive MS? ThedefinitionofprogressiveMShaschanged during the past 150 years. First described by the French neurologist Jean-Martin Charcot in 1868, the disease was recognized as presenting with an initial course of clinical attacks or relapses. However, a small group of patientsexperienceaprogressiveaccumulation of disability from onset. Progressive forms of MS were initially grouped into the category of “chronic progressive” MS. In1996,aninternationalsurveyofclinicians involved in the care of MS patients proposed a standardized definition forthe most common clinical courses of the disease. This resulted in terminologyfor four subtypes of MS: relapsing remitting,secondaryprogressive, primary progressive, and progressive-relapsing MS. Thesedefinitionswereintended to standardize the language used to describe common clinical patterns of the disease. Based on this terminology, PPMS was defined as a progressive disease course from onset, without relapses. However, these terms led to the assumption that each clinical category represented a differentdiseaseprocesswithdifferentresponse to treatments and prognosis. In order to avoid confusion, these clinical types were updated in 2014. This new terminology focused on two main areas: presence or absence of clinical activity,andpresenceorabsenceofprogression. With the new designations, all MS types are now classified as either “active” or “inactive”, and “progressive” or “nonprogressive” (based Primary progressive was defined as a progressive disease course from onset, without relapses.