To describe the natural history of a condition or disease. To describe the natural history of a condition or disease. To determine effectiveness or cost effectiveness of treatments/services and/or health care products. To measure or monitor safety and harm. To measure quality of care.
According to the NMSS, attacks or flare-ups of symptoms only qualify as exacerbations if: 1  they occur at least 30 days from an earlier flare-up. 2  symptoms last for 24 hours or longer.
The average life expectancy for someone with MS is 35 years after the symptoms begin. This represents a life expectancy of 95 percent of someone who does not have multiple sclerosis. Most people with the disease can function effectively; however, a rare form of acute MS can be fatal within weeks.