What medical conditions are people with Multiple Sclerosis (MS) prone to?

Medical Conditions Common in Multiple Sclerosis Patients

People with Multiple Sclerosis (MS) are particularly prone to infections, neuroinflammatory complications, and autoimmune comorbidities due to both the disease itself and its treatments. 1, 2

Infection Susceptibility

MS patients have significantly increased risk of infections due to several factors:

• Immune System Dysfunction: MS itself causes malfunction of the immune regulation of plasma cells 2
• Treatment-Related Immunosuppression: Disease-modifying therapies (DMTs) often suppress immune function 1
• Specific Infection Risks:
  • Respiratory infections: Particularly pneumococcal disease with increased risk of severe invasive disease 2
  • Urinary tract infections: Common due to neurogenic bladder dysfunction 1
  • Viral reactivations: Including:
    • Varicella zoster virus (VZV) - causing shingles 2
    • Cytomegalovirus (CMV) - reactivation in 11-35% of MS patients after certain treatments 2
    • Epstein-Barr virus (EBV) - reactivation in 34-100% after specific treatments 2
    • Hepatitis B virus (HBV) - risk of reactivation 2
  • Opportunistic infections: Including Pneumocystis jirovecii pneumonia (PJP) 2

Neurological and Cognitive Conditions

MS patients commonly experience:

• Cognitive impairment: Affecting 40-70% of MS patients 1
• Neuroinflammation: Persistent inflammatory processes in the central nervous system 2
• ME/CFS-like syndrome: Many MS patients develop symptoms similar to Myalgic Encephalomyelitis/Chronic Fatigue Syndrome 2
• Dysautonomia: Dysfunction of the autonomic nervous system 2

Endocrine and Metabolic Disorders

• Hypothalamus-pituitary-adrenal axis dysfunction: Leading to abnormal cortisol levels 2
• Vitamin D deficiency: Common in MS patients and associated with increased disease activity 2
• Obesity-related complications: Obesity increases MS risk and can worsen outcomes 2

Ophthalmologic Complications

MS patients frequently develop:

• Optic neuritis: Inflammation of the optic nerve 1
• Corneal small nerve fiber loss: Affecting eye health 2
• Retinal abnormalities: Including hemorrhages, cotton wool spots, and retinal vein occlusion 2
• Impaired pupillary light responses: Affecting vision 2
• Retinal microcirculation impairment: Affecting eye health 2

Vascular and Cardiovascular Issues

• Vascular and endothelial abnormalities: Including deformed red blood cells 2
• Reduced blood volume: Affecting circulation 2
• Brain microhemorrhages: Small bleeds in the brain 2
• Reduced cerebral blood flow: Affecting brain function 2

Exercise and Energy Metabolism Issues

• Exercise intolerance: Difficulty with physical activity 2
• Impaired oxygen consumption: Affecting energy levels 2
• Reduced anaerobic threshold: Limiting physical capacity 2
• Mitochondrial dysfunction: Affecting cellular energy production 2

Important Clinical Considerations

1. Vaccination Protocol: MS patients should follow specific vaccination schedules, particularly after treatments like autologous hematopoietic stem cell transplantation (AHSCT) 2

   • Pneumococcal vaccination: Three doses at 1-month intervals starting 3-6 months after transplantation
   • Annual influenza vaccination
   • Recombinant VZV vaccine 6 months after transplantation
   • SARS-CoV-2 vaccination according to national guidelines

2. Monitoring Requirements:

   • Regular screening for viral reactivations, especially after intensive treatments 2
   • Vigilance for opportunistic infections in patients on B-cell depleting therapies 2
   • Regular assessment of cognitive function 1

3. Treatment Implications:

   • Infection risk varies by treatment type, with higher risks associated with certain immunosuppressive therapies 2
   • Consider prophylactic antimicrobials for patients at high risk of infection 2
   • Monitor for treatment-specific complications (e.g., PML with certain DMTs) 1

Understanding these common comorbidities and complications is essential for comprehensive care of MS patients, as they significantly impact morbidity, mortality, and quality of life.