Prevalence of Progression Independent of Relapse Activity and Relapse-Associated Worsening in Patients With AQP4-IgG-Positive NMOSD
Siriratnam P, Huda S, Van Der Walt A, Sanfilippo PG, Sharmin S, Foong YC, Yeh WZ, Zhu C, Khoury SJ, Csepany T, Willekens B, Etemadifar M, Ozakbas S, Nytrova P, Altintas A, Al-Asmi A, Ramo-Tello CM, Laureys G, Patti F, Horakova D, Foschi M, Boz C, Mccombe PA, Turkoglu R, Lechner-Scott J, Roos I, Kalincik T, Jokubaitis VG, Butzkueven H, Monif M; for MSBase.
Neurology. 2024 Dec 24;103(12):e209940. doi: 10.1212/WNL.0000000000209940. Epub 2024 Nov 19. PMID: 39561307.
Abstract
Objectives
In aquaporin-4 antibody–positive neuromyelitis optica spectrum disorder (AQP4-IgG NMOSD), disability accrual is mostly attributed to relapses. This study aimed to assess the prevalence of progression independent of relapse activity (PIRA) and relapse-associated worsening (RAW) in AQP4-IgG NMOSD.
Methods
This was a retrospective cohort study of patients with AQP4-IgG NMOSD enrolled in the MSBase international data registry. Patients required a minimum of 3 recorded Expanded Disability Status Scale (EDSS) scores: baseline, event, and a 6-month confirmation score. Presence and absence of relapses between the baseline and event EDSS scores determined RAW and PIRA, respectively. Descriptive statistics were used to present the results.
Results
A total of 181 patients followed for a median of 4.5 years (Q1 1.7, Q3 7.8) were included. Most patients were female (88.4%), and the median age at disease onset was 38.1 years. Overall, 4 patients (2.2%) developed 5 incidences of PIRA and 13 patients developed RAW (7.2%).
Discussion
This multicenter study highlights that PIRA is very rare in AQP4-IgG NMOSD. Limitations of this study include the sole focus of overall EDSS to measure disability, lack of requirement for a second EDSS score to confirm baseline EDSS, and the absence of magnetic resonance imaging information for all patients.
