Heart rate variability and fatigue in MS: two parallel pathways representing disseminated inflammatory processes?

Area of Science:

• Neurology
• Immunology
• Cardiology

Background:

• Fatigue is a significant, poorly understood symptom in multiple sclerosis (MS).
• A proposed model links MS fatigue to inflammatory processes.
• Evaluating this model requires demonstrating a connection between fatigue and vagal activation, assessed via heart rate variability (HRV).

Purpose of the Study:

• To review evidence on heart rate variability (HRV) changes in MS patients.
• To explore the relationship between HRV, fatigue, and disease progression in MS.
• To assess the validity of a model proposing inflammation as a cause of MS fatigue.

Main Methods:

• A narrative review of 45 relevant scientific articles.
• Analysis of heart rate variability (HRV) data in multiple sclerosis (MS) patients.
• Examination of the link between inflammation, HRV, and fatigue.

Main Results:

• Inflammation impacts cardiac function in both animal and human models.
• MS patients exhibit HRV changes consistent with acute and chronic inflammation.
• Evidence supports a correlation between fatigue levels and parallel HRV changes in MS.
• MS-related neurological damage does not fully account for HRV changes, supporting a link with fatigue.

Conclusions:

• The review supports a model where fatigue and HRV changes in MS reflect underlying autoimmune processes.
• Further observational and experimental studies are proposed to investigate the common pathway of fatigue and HRV in MS.
• Fatigue and HRV may serve as indicators of activated autoimmune processes in multiple sclerosis.