Background The pathological burden of spinocerebellar ataxia type 3, also known as Machado–Joseph disease (SCA3/MJD), accumulates before the beginning of symptoms. Our study aims at validating biomarkers for disease progression since pre‐ataxic periods. We report on baseline findings of clinical scales and oculomotor neurophysiology. Methods Ataxic (Scale for the Assessment and Rating of Ataxia > 2.5) and at 50% risk subjects were included. The latter were subdivided into noncarriers, pre‐ataxic carriers near (PAN), or pre‐ataxic carriers far from (PAFF) ataxia onset (AO), with 4 years from the predicted age at onset being the cutoff. The subjects were assessed by Neurological Examination Score for Spinocerebellar Ataxia (NESSCA), International Cooperative Ataxia Rating Scale (ICARS), Inventory of Non‐Ataxic Signs (INAScount), Composite Cerebellar Functions Score and SCA Functional Index, and video‐oculography, including the regression slope of vestibulo‐ocular reflex gain (VORr), main sequence of volitional and reflexive vertical saccades, slow‐phase velocity of central and gaze‐evoked (SPV‐GE) nystagmus, and vertical pursuit gain. Correction for multiple comparisons was performed; the threshold for statistical significance was P < 0.05. Results A total of 35 ataxic, 14 PAN, 24 PAFF, and 22 noncarriers were included. All variables showed significant differences between groups and correlated to time to onset or time after onset, among all 73 SCA3/MJD carriers; none significantly changed with age in controls. NESSCA, ICARS, INAScount, VORr, main sequence of volitional saccades, and SPV‐GE not only distinguished PAN from controls but also correlated with time left to AO. Conclusions Clinical scales and video‐oculography variables were already altered in pre‐ataxic SCA3/MJD carriers and worsened with time. NESSCA, ICARS, INAScount, VORr, main sequence of vertical volitional saccades, and SPV‐GE are good candidates to measure preclinical changes in SCA3/MJD. © 2021 International Parkinson and Movement Disorder Society

Background: Functional capacity assessment is important in patients with chronic obstructive pulmonary disease (COPD). It can be performed by the six-minute walk test (6MWT) on a 30meter track. However, such space is not always available in clinical settings. Objectives: To compare the performance between the 6MWT on a 30-(6MWT 30 ) and 20-meter (6MWT 20 ) track; to evaluate the validity and reliability of the 6MWT 30 and the 6MWT 20 ; and to determine for which patients track length has the greatest impact on performance. Methods: Patients with COPD randomly performed two 6MWT 30 and two 6MWT 20 on two different days and were also assessed using the COPD Assessment Test (CAT) and modified Medical Research Council (mMRC) scale. Results: Thirty patients (23 men; mean ± standard deviation FEV 1 %pred: 45.6 ± 12.1) participated in the study. They walked a greater distance on the 6MWT 30 than on the 6MWT 20 [mean difference: 22.1 m (95% CI: 12, 32 m)]. The longer the 6MWT 30 distance, the greater the difference between the 2 tests (r = 0.51; p = 0.004). The 6MWT 20 showed high reliability [ICC: 0.96 (95% CI: 0.77, 0.99)] and the results were associated with the distance walked on the 6MWT 30 (r = 0.86), CAT (r = −0.53), and mMRC (r = −0.62). Patients who walked ≥430 m in the 6MWT 30 presented a difference between the tests greater than those who walked <430 m (34.5 ± 23.3 m vs. 12.6 ± 24.1 m; respectively; p = 0.01).

No abstract

No abstract