Scientists and medical professionals have not yet agreed upon a clear definition of aggressive MS. However, doctors may use the term to refer to MS that progresses rapidly, involves frequent and severe relapses, and causes rapid and permanent disability.
Multiple sclerosis (MS) is an autoimmune condition that affects the central nervous system (CNS).
This article provides a working definition of aggressive MS, according to the latest scientific research. It also outlines the features, symptoms, and complications of aggressive MS, and provides information on its diagnosis, treatment, and outlook.

As the authors of a
The authors of a
- frequent and severe worsening of MS symptoms, which doctors refer to as “MS relapses“
- incomplete recovery from MS relapses
- rapidly progressing and permanent disability
However, scientists do not yet agree on how to quantify the above measures.
To complicate matters further, the
Since there is no formal definition of aggressive MS, scientists are not yet able to provide a list of its associated features and symptoms.
However, the 2023 Frontiers in Neurology article does list some common features of both “aggressive” and “highly active” MS. These are:
- the occurrence of more than two relapses per year in people who have not received treatment
- the occurrence of more than one relapse per year in people who have received treatment
- evidence of more than two contrast-enhancing brain lesions on a magnetic resonance imaging (MRI) scan
According to a
- vision problems
- vertigo
- weakness
- fatigue
- loss of sensation
According to the
- at least two contrast-enhancing brain lesions, as indicated on an MRI scan either at the onset of the condition or during an early follow-up
- 20 or more lesions on an MRI scan at the condition’s onset
- elevated levels of the protein “neurofilament light chain” in either the blood or the cerebrospinal fluid, which indicates damage to long nerve fibers called axons, either at the time of diagnosis or during follow-up.
According to a
In general, MS treatments may include
- Medications to reduce relapse severity: High dose corticosteroids are the
first-line treatment for MS. These medications work by suppressing the immune system and speeding up a person’s recovery in relapsing forms of MS. - Medications to reduce relapse frequency: Disease-modifying therapies (DMTs) aim to reduce the amount of damage and scarring to the myelin sheath surrounding the nerves. They may also help slow long-term disability, though further research is necessary to demonstrate their long-term benefits. They have also been shown to reduce relapses of MS.
- Treatments to help manage symptoms: Symptom management may involve a combination of treatments, including medications, physical therapy, and lifestyle changes.
Multiple sclerosis is a serious condition that can cause multiple complications. These may
- fatigue
- cognitive impairment
- mood disorders
- mobility impairment
- tremors
- vertigo
- double vision
- difficulty swallowing
- constipation
- urinary tract infections
- erectile dysfunction
- sleep disorders
Due to a lack of scientific consensus regarding the definition of aggressive MS, it is difficult to give an accurate outlook for this disease.
As one
A person should talk with their doctor for more information on their individual treatment options and outlook.
Multiple sclerosis (MS) is an autoimmune condition that causes damage to the protective layers surrounding the nerves of the CNS. The condition can cause a range of symptoms and may result in mild to severe disability.
Scientists have yet to agree on a definition of aggressive MS. However, doctors may use this terminology to refer to MS that progresses rapidly, involves frequent and severe relapses, and causes permanent disability or death within a relatively short timeframe.
Medical experts have not yet established a specific treatment plan for aggressive MS, partly because there is no clear definition of the disease and its features. Anyone who has received a diagnosis of MS and is experiencing worsening symptoms of the disease should talk with their doctor. A doctor can offer insights into the person’s individual diagnosis, treatment options, and outlook.