Longitudinal Decline in Electrochemical Skin Conductance Reflects Disease Progression in Multiple System Atrophy

Area of Science:

• Neurology
• Autonomic Neuroscience
• Biomarker Discovery

Background:

• Multiple System Atrophy (MSA) presents with progressive autonomic and motor dysfunction.
• Currently, there is a lack of robust biomarkers for tracking MSA progression.
• Electrochemical skin conductance (ESC) offers a noninvasive method to assess sudomotor function, but its utility in MSA requires further investigation.

Purpose of the Study:

• To comprehensively evaluate the longitudinal predictive and prognostic value of ESC in a large cohort of MSA patients.
• To compare the efficacy of ESC against traditional measures like orthostatic blood pressure (BP) and autonomic symptom scales.

Main Methods:

• Analysis of 175 MSA patients with a mean follow-up of 4.2 years.
• Assessment of disease severity using UMSARS, COMPASS31, SCOPA-AUT, and orthostatic BP.
• Measurement of hand and foot ESC using Sudoscan.
• Statistical analysis included linear mixed-effects models, correlations, cross-validation, and Cox proportional hazards models for mortality prediction.

Main Results:

• ESC showed strong inverse associations with UMSARS scores (P < 0.0001).
• ESC significantly declined over time, mirroring UMSARS progression (P < 0.001).
• ESC outperformed orthostatic BP in predicting disease severity and independently predicted lower mortality.

Conclusions:

• ESC serves as a sensitive biomarker for MSA severity, progression, and survival.
• ESC demonstrates superior prognostic value compared to orthostatic BP measures.
• The simplicity and predictive power of ESC support its integration into routine MSA monitoring and clinical trials.