Multiple sclerosis commonly presents in young adults. They often have a relapsing-remitting multiple sclerosis course. Dr. Anton Titov, MD. In the majority of patients, multiple sclerosis eventually becomes progressively disabling. It is called secondary progressive multiple sclerosis. Studies of natural history of multiple sclerosis showed that age affects multiple sclerosis progression independent of the disease duration. Dr. Anton Titov, MD. You have done sophisticated MRI analysis of multiple sclerosis cases. Dr. Paul M. Matthews, MD. Multiple sclerosis patients that you studied were similar in everything except the age of the patients. Dr. Anton Titov, MD. What did your clinical trial show? What are its implications for treatment of patients with multiple sclerosis? Dr. Paul M. Matthews, MD. The clinical trial attempted to control for the duration of multiple sclerosis in a group of patients from a common middle age. It showed the following results. Older patients more often had a more aggressive clinical course. It was associated with more profound problems, particularly in the diffuse white matter of the brain. This suggested the greater loss of brain cells and axons. Older patients with multiple sclerosis had more neurodegeneration. This in itself is consistent with long-standing clinical epidemiological data. It has suggested that patients show different rates of progression of multiple sclerosis. Rate of progression depended on the age, at which they first present with multiple sclerosis. Dr. Paul M. Matthews, MD. This clinical trial also highlights the differences in sex ratios between those who present with multiple sclerosis first in mid-life as opposed to early in life. Altogether these factors suggest that there is a strong interaction between the inflammatory processes and the subsequent neurodegeneration. Multiple sclerosis and aging of the brain are likely related to each other. This relates to many other neurodegenerative disorders, in an interesting way. Dr. Paul M. Matthews, MD. Of course, the most common of neurodegenerative disorders is Alzheimer's disease. For all these diseases the single greatest risk connector is, of course, age of a patient. Dr. Anton Titov, MD. There are other predisposing biological factors for neurodegenerative diseases, including multiple sclerosis.