Publication: Fars-ADL across ataxias: construct validity, sensitivity to change, and minimal important change
Program
KU-Authors
KU Authors
Co-Authors
Traschuetz, Andreas
Fleszar, Zofia
Hengel, Holger
Klockgether, Thomas
Erdlenbruch, Friedrich
Falkenburger, Bjoern H.
Klopstock, Thomas
Pedroso, Jose Luiz
Santorelli, Filippo M.
Schoels, Ludger
Advisor
Publication Date
2024
Language
en
Type
Journal article
Journal Title
Journal ISSN
Volume Title
Abstract
Background: Patient-focused outcomes present a central need for trial-readiness across all ataxias. The Activities of Daily Living part of the Friedreich Ataxia Rating Scale (FARS-ADL) captures functional impairment and longitudinal change but is only validated in Friedreich Ataxia. Objective: Validation of FARS-ADL regarding disease severity and patient-meaningful impairment, and its sensitivity to change across genetic ataxias. Methods: Real-world registry data of FARS-ADL in 298 ataxia patients across genotypes were analyzed, including (1) cross-correlation with FARS-stage, Scale for the Assessment and Rating of Ataxia (SARA), Patient-Reported Outcome Measure (PROM)-ataxia, and European Quality of Life 5 Dimensions visual analogue scale (EQ5D-VAS); (2) sensitivity to change within a trial-relevant 1-year median follow-up, anchored in Patient Global Impression of Change (PGI-C); and (3) general linear modeling of factors age, sex, and depression (nine-item Patient Health Questionnaire [PHQ-9]). Results: FARS-ADL correlated with overall disability (rho(FARS-stage) = 0.79), clinical disease severity (rho(SARA) = 0.80), and patient-reported impairment (rho(PROM-ataxia) = 0.69, rho(EQ5D-VAS) = -0.37), indicating comprehensive construct validity. Also at item level, and validated within genotype (SCA3, RFC1), FARS-ADL correlated with the corresponding SARA effector domains; and all items correlated to EQ5D-VAS quality of life. FARS-ADL was sensitive to change at a 1-year interval, progressing only in patients with worsening PGI-C. Minimal important change was 1.1. points based on intraindividual variability in patients with stable PGI-C. Depression was captured using FARS-ADL (+0.3 points/PHQ-9 count) and EQ5D-VAS, but not FARS-stage or SARA. Conclusion: FARS-ADL reflects both disease severity and patient-meaningful impairment across genetic ataxias, with sensitivity to change in trial-relevant timescales in patients perceiving change. It thus presents a promising patient-focused outcome for upcoming ataxia trials.
Description
Source:
Movement Disorders
Publisher:
Wiley
Keywords:
Subject
Clinical neurology