The Clinical Utility of Sudoscan as a Biomarker for Parkinson's Disease with Lewy Bodies (P5.364)

Abstract

Objective: To describe sudomotor function and its association to autonomic function and PD clinical variables in carriers of E46K mutation (E46K-SNCA), idiopathic Parkinson’s disease (iPD), dementia with Lewy bodies (DLB) and healthy controls (HC). Background: Phosphorylated alpha-synuclein (Lewy bodies, LB and Lewy neurites), the pathological hallmark of PD, has been reported in small peripheral nerves. SUDOSCAN is a non-invasive device that has demonstrated its capacity to detect sudomotor dysfunction. However, we still don’t know its association to cardiac MIBG Scintigraphy and clinical measures of PD. Methods: We evaluated cross-sectionally 48 sex/age matched participants: n=7 E46K-SNCA [4 motor parkinsonism, 1 with cough syncopes and 2 asymptomatic], n=19 iPD, n=3 DLB and n=19 HC. We obtained: electrochemical skin conductance in hands (HESC) and feet (FESC); myocardial/mediastinal uptake ratios (H/M) (all E46K-SNCA, n=12 iPD, n=2 DLB and n=1 HC); heart rate and blood pressure variability; SCOPA-AUT questionnaire and Ewing tests; PD manifestations (UPDRS, Hoehn and Yahr and cognition). Results: Symptomatic E46K-SNCA and DLB had lower HESC (E46K-SNCA: 62.4; DLB: 57.7; iPD: 69.7; HC: 71.2 us) (p ≤ 0.05) and FESC (E46K-SNCA: 70.4; DLB: 68.7; iPD: 74.4; HC: 74.5 us) (p above 0.05). Higher HESC asymmetry correlated with increased disease duration and L-Dopa levels. Lower HESC and FESC were associated to lower early MIBG H/M uptake and lower Valsalva ratio in patients (p<0.05), and this remained significant for FESC after removing the effect of disease duration and L-Dopa levels. Conclusions: Patients with PD had sudomotor dysfunction in hands and feet that was more severe in LB synucleinopathies (DLB and E46K-SNCA mutation). This sudomotor dysfunction was associated to myocardial sympathetic denervation and cardiovagal dysfunction even after removing the effect of disease duration and L-Dopa. These findings support the potential utility of Sudoscan as a biomarker of peripheral autonomic nervous system damage in PD with LB.

Disclosure: Dr. Gabilondo has nothing to disclose. Dr. Tijero has nothing to disclose. Dr. Gonzalez has nothing to disclose. Dr. Acera has nothing to disclose. Dr. Llorens has nothing to disclose. Dr. Gardeazabal has nothing to disclose. Dr. Luquin has nothing to disclose. Dr. Carmona has nothing to disclose. Dr. Gomez Esteban has nothing to disclose.