MS Epidemiology: Who Is Affected and Where Unmet Need Remains

Welcome back to another AJMC Peer Exchange series. In "MS Epidemiology: Who Is Affected and Where Unmet Need Remains," moderator Kavita Nair, PhD is joined by Leorah Freeman, MD, PhD, Scott Newsome, DO, MSCS, FAAN, FANA, and Erin Longbrake, MD, PhD to open the series on multiple sclerosis.

Dr. Nair introduces the program and the panel, and each physician shares a title and institutional affiliation. She then notes that roughly one million people in the United States live with MS and that the number keeps climbing.

Dr. Newsome says one million is probably an underestimate. Some people with milder disease may not see a neurologist for many years. He adds that prevalence has risen substantially compared with a couple of decades ago, and the panel debates whether MRI and earlier diagnosis explain part of that increase. MS remains the most common autoimmune neurological condition worldwide. Women are affected roughly three times as often as men, and onset typically occurs between the 20s and 50s. Pediatric-onset disease still occurs but is uncommon.

Dr. Freeman points out that late-onset MS is increasingly recognized, with patients now presenting about a decade later. This has implications for how clinicians treat active disease in older adults. Dr. Longbrake challenges the stereotype of MS as a disease of young white women. She notes that it is diagnosed in older and younger patients and in Black patients and people of other ethnicities, and she believes the stereotype does more harm than good.

Dr. Newsome adds that older studies linked higher prevalence to greater distance from the equator. He stresses that MS is not a one-hit phenomenon, because many factors lead someone down the path to disease.

Dr. Nair then asks where unmet need persists. Dr. Newsome answers that progressive biology is the largest gap. Current medications are very good at shutting down macroscopic relapsing biology, meaning what clinicians see on MRI and hear from patients. Microscopic change continues, however, and more research is needed to identify new treatment targets.

The next episode in this series, "MS Progression Explained: Relapse-Associated Worsening vs PIRA," features Dr. Freeman explaining how relapse-driven and relapse-independent processes shape disability.