Background: We aimed to evaluate the role of autonomic nervous system (ANS) abnormalities on disease activity (relapses and new MRI lesions) and disease progression in people with clinically isolated syndrome (pwCIS).
Methods: Out of 121 consecutive pwCIS, data on disease activity and progression after 2.9 (1.4-4.1) years of follow-up, was available for 94 pwCIS. Baseline characteristics included MRI parameters, Composite Autonomic System Score-31 (COMPASS-31), Composite Autonomic Scoring Scale, and supine and standing levels of epinephrine and norepinephrine.
Results: Univariable logistic regression analysis revealed three predictors for occurrence of new relapse, COMPASS-31 > 7.32, total number of T2 lesions > 3 and decreasing supine level of epinephrine. The Kaplan-Meier survival analysis showed that patients with COMPASS-31 > 7.32 have statistically significant lower probability that they will be relapse free (p = 0.013). It has also showed that the relative risk reduction for occurrence of new relapse in participants with COMPASS < 7.32 was 46%. The multivariable regression model confirmed that COMPASS-31 > 7.32 and total number of T2 lesions > 3 increase the likelihood and the increasing supine level of epinephrine reduces the likelihood for a relapse. Finally, results of the Cox regression analysis showed, that after controlling for age, sex, total number of T2 lesions > 3 and supine level of epinephrine, the hazard for occurrence of new relapse for participants with COMPASS-31 > 7.32 is 2.7 times that of participants with COMPASS-31 < 7.32.
Conclusion: This study provides evidence that ANS is an important contributor to development of disease activity in pwCIS.
Keywords: Autonomic nervous system; COMPASS-31; MRI; Multiple sclerosis.
Copyright © 2019. Published by Elsevier B.V.