Did you know…
MS is classified into four main types by the National MS Society Advisory Committee on Clinical Trials in MS. The types are based on the phase and severity of disease progression.
The four types are:
- Clinically Isolated Syndrome
Clinically isolated syndrome (CIS) represents a single event, the first episode of neurological symptoms. On its own, it is not indicative of MS, unless MRI scans show lesions in the brain.
- Relapsing-Remitting Multiple Sclerosis
Relapsing-remitting multiple sclerosis (RRMS) is the most common type of MS. Patients experience attacks of increasing neurological symptoms, called exacerbations or relapses, followed by periods of partial or complete recovery. At various times, patients may have active, not active, or worsening neurological symptoms.
- Secondary Progressive Multiple Sclerosis
Secondary progressive multiple sclerosis (SPMS) is the secondary stage of MS that follows RRMS. Patients may have relapsing-remitting episodes initially but then experience a steady worsening of neurological symptoms.
- Primary Progressive Multiple Sclerosis
Primary progressive multiple Sclerosis (PPMS) affects about 15 percent of MS patients. Patients experience a steady decline in neurological function without relapses from the onset of symptoms.