Multiple sclerosis or MS is a degenerative condition that causes the immune system to attack the body’s nervous system. This affects the brain and the spinal cord, which further leads to the dysfunction of the central nervous system. The pattern of nerve damage varies from patient to patient. Based on some generic factors, doctors have categorized multiple sclerosis into four major types. Here are the types of multiple sclerosis and the associated risk factors.
Relapsing-Remitting Multiple Sclerosis (RRMS)
About 75-85% of MS cases fall under this category. A major risk factor of this type of MS is exposure to the Epstein-Barr virus or EBV. Women are at a higher risk than men. The symptoms begin to appear in the early 20s, in most cases. Relapses or attacks of the symptoms begin to appear on a regular basis. The relapses are followed by episodes of recovery. These episodes, called remissions, may last for weeks, months, or even years. The type of nerve affected by this category of MS and the severity of the symptoms as well as period of recovery varies from person to person.
Secondary Progressive Multiple Sclerosis (SPMS)
The risk of secondary progressive MS is higher for those with a preexisting condition of RRMS. The symptoms begin to appear without any relapses or remissions. This usually happens after 10 to 12 years of relapsing-remitting MS diagnosis. This usually happens to those groups of MS patients who do not fully recover from MS relapses. About 50% of those with relapsing-remitting MS are diagnosed with secondary progressive MS. Although there is less inflammation, the nerve damage is quite substantial. The severity of the symptoms increases, leading to a decline in quality of life. Secondary progressive multiple sclerosis is harder to treat.
Primary Progressive Multiple Sclerosis (PPMS)
This is a rare category of multiple sclerosis. Roughly 10 percent of MS cases are primary progressive multiple sclerosis. There are neither flare-ups of symptoms, nor any remissions. In fact, the symptoms worsen over time. Moreover, the effectiveness of treatments for this type of MS is quite low. People who are above 40 years of age are at a higher risk of being diagnosed with primary progressive multiple sclerosis. Both men and women are at an equal risk. This type of MS often leads to disability.
Progressive Relapsing Multiple Sclerosis (PRMS)
This is the rarest form of multiple sclerosis. Approximately 5% of MS cases are progressive relapsing multiple sclerosis. In this case, the symptoms become severe and worse steadily right from the start. The exact cause of PRMS is unknown. Those in their mid to late 30s are at a higher risk. Family history of MS may play a role in the increased risk of PRMS in certain patients. There are episodes of acute flare-ups or releases. However, there is no respite from the condition since there is no remission.