Almost 150 years since multiple sclerosis was first recognised, we know that MS is an auto-immune disorder but we still do not know exactly what triggers this, and why it affects some people and not others.
There are several theories and most experts agree that MS is probably due to a combination of genetic and environmental factors.
Types of multiple sclerosis
There are 4 main types:Â
Relapsing remitting multiple sclerosis (RRMS)
Symptoms appear sporadically during a relapse, followed by full or partial recovery during a period of remission.Â
Secondary progressive multiple sclerosis (SPMS)
Symptoms progressively increase, but this might be very slow and barely noticeable.
Primary progressive multiple sclerosis (PPMS)
Symptoms gradually get worse from the start, rather than appearing as relapses.
Benign multiple sclerosis (BMS)
Only very occasional relapses, with good recovery in-between, and minimal symptoms over 10 to 20 years.