Multiple sclerosis is primarily a neurodegenerative disease.

Area of Science:

• Neuroimmunology
• Neurodegeneration
• Central Nervous System Disorders

Background:

• The established view of multiple sclerosis (MS) as a primary immune-mediated disease is questioned.
• Current therapies targeting the immune system have limited efficacy for many MS patients.
• Progressive degeneration of brain and spinal cord tissue is a key feature of MS.

Purpose of the Study:

• To challenge the prevailing immunopathogenesis model of multiple sclerosis.
• To propose a primary neurodegenerative basis for multiple sclerosis.
• To re-evaluate the role of the immune system and other factors in MS.

Main Methods:

• Critical review of existing multiple sclerosis literature.
• Analysis of the natural history and pathological hallmarks of MS.
• Consideration of the blood-brain barrier's role in MS pathogenesis.

Main Results:

• The assumption of primary immunopathogenesis for MS is considered flawed.
• Neurodegeneration, impacting grey and white matter, is integral to MS.
• Demyelination is viewed as part of the neurodegenerative process, not the primary target.
• The integrity of the blood-brain barrier is crucial for the primary neurodegenerative pathology.
• Primary progressive MS exemplifies a neurodegenerative disease.
• Relapsing-remitting MS may reflect modifications by hormones on CNS metabolism.

Conclusions:

• Multiple sclerosis is fundamentally a neurodegenerative disease.
• The blood-brain barrier integrity is critical in MS neurodegeneration.
• Hormonal factors may modulate the neurodegenerative process in certain MS forms.