P269 Small fiber assessment by sudoscan in transthyretin familial amyloid polyneuropathy treated patients – A longitudinal study. Issue 9 (September 2017)

• Record Type: Journal Article
• Authors: Castro, José; Costa, João Costa; Castro, Isabel; Abreu, Daisy; Gonçalves, Nilza; Conceição, Isabel
• Is Part Of: Clinical neurophysiology. Volume 128:Issue 9(2017:Sep.)
• Page Start: e265
• Publication Date: 2017-09
• Subjects: Sudoscan -- Tafamidis -- Transthyretin familial amyloid polyneuropathy -- Sudomotor function; Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2017.07.277
• Languages: English
• ISSNs: 1388-2457

Abstract

Abstract : Objective: To prospectively assess small fiber involvement in Transthyretin familial amyloid polyneuropathy (TTR-FAP). Methods: We studied 116 TTR-FAP Val30Met subjects (59 asymptomatic carriers, 45 tafamidis-treated, and 12 liver transplanted) at three time ( t ) points separated by a mean of 12.5(±4.2) and 11.5(±3.2) months between t 1– t 2 and t 2– t 3, respectively. Sural nerve action potential (SNAP), palmar and plantar sympathetic skin response (SSR) and electrochemical skin conductance (ESC) measured by Sudoscan in hands and feet were evaluated. Neuropathy Impairment Scale (NIS) and Body mass index (BMI) were recorded. Adjusted generalized linear model repeated measures was used for comparisons (level of significance set at 0.01). Results: As expected, sural SNAP, plantar SSR, and feet and hands ESC, were significantly lower in tafamidis and transplanted groups ( p < 0.009) in comparison to carriers. Among carriers, none of the tests assessing small fiber involvement showed a significant decrease over the study period time. Among tafamidis-treated patients, feet ESC was the only test that significantly decreased over time ( p < 0.001). Hand ESC also decreased ( p = 0.02). No significant changes in any of the tests were detected through time among transplanted patients but the sample size was small. Overall, male sex was associated with a lower feet ESC ( p = 0.003). Discussion: Sudomotor function seems to decline over time among tafamidis-treated patients. Conclusions: Small fiber neuropathy progression seems not to be totally halted by tafamidis treatment, as assessed with Sudoscan. Significance: Sudoscan appears to be a non-invasive, easy and reproducible test to assess disease progression and treatment effectiveness in TTR-FAP.