Sudomotor dysfunction is frequent and correlates with disability in Friedreich ataxia

Author(s)

Takazaki, Karen A. G. ^[1] ; Rezende, Thiago Junqueira R. ^[1] ; Martinez, Alberto R. M. ^[1] ; Gonzalez-Salazar, Carelis ^[1] ; Nucci, Anamarli ^[1] ; Lopes-Cendes, Iscia ^[2] ; Franca, Jr., Marcondes C. ^[1]

Affiliation

^[1] Univ Campinas UNICAMP, Sch Med Sci, Dept Neurol, Campinas, SP - Brazil

^[2] Univ Campinas UNICAMP, Sch Med Sci, Med Genet, Campinas, SP - Brazil

• Document type: Journal article
• Source: CLINICAL NEUROPHYSIOLOGY; v. 129, n. 11, p. 2290-2295, NOV 2018.
• Web of Science Citations: 1

Abstract

Objectives: To evaluate autonomic symptoms and function in Friedreich's Ataxia (FRDA). Methods: Twenty-eight FRDA patients and 24 controls underwent clinical/electrophysiological testing. We employed the Friedreich's Ataxia Rating Scale (FARS) and the Scales for Outcomes in Parkinson's Disease: Autonomic Questionnaire-SCOPA-AUT to estimate the intensity of ataxia and autonomic complaints, respectively. Cardiovagal tests and the quantitative sudomotor axonal reflex, QSART, were then assessed in both groups. Results: In the patient group, there were 11 men with mean age of 31.5 +/- 11.1 years. Mean SCOPA-AUT score was 15.1 +/- 8.1. Minimum RR interval at rest was shorter in the FRDA group (Median 831.3 x 724.0 ms, p < 0.001). The 30:15 ratio, Valsalva index, E:I ratio, low and high frequency power presented no differences between patients and controls (p > 0.05). Sweat responses were significantly reduced in patients for all sites tested (forearm 0.389 x 1.309 mu L; proximal leg 0.406 x 1.107 mu L; distal leg 0.491 x 1.232 mu L; foot 0.265 x 0.708 mu L; p value < 0.05). Sweat volumes correlated with FARS scores. Conclusions: We found abnormal sudomotor but normal heart rate variability in FRDA. Small cholinergic post-ganglionic fibers are affected in the disease. Significance: Quantification of sudomotor function might be a biomarker for FRDA. (C) 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 13/01766-7 - Sensory neuronopathies: investigation of new diagnostic methods, mechanisms of the disease and therapeutic strategies
• Grantee: Marcondes Cavalcante Franca Junior
• Support Opportunities: Research Grants - Young Investigators Grants