Research Presented at ANA 2024 Reveals Association Between Paramagnetic Rim Lesions and Disability/Disease Progression in People with MS

For people with multiple sclerosis (MS), a higher number of persisting paramagnetic rim lesions (PRLs) was associated with increased odds of progression independent of relapse activity (PIRA) and confirmed disability progression (CDP), according to data presented at the 2024 annual meeting of the American Neurological Association (ANA). Further, the study findings demonstrate that removing all persisting PRLs and preventing new PRLs would significantly reduce disability and disease progression for people with MS.

The study included a cohort of 93 people with MS who had 3T MRI imaging at baseline with sufficient clinical data to determine incidence of CDP and PIRA over 5 years of follow up. Researchers identified PRLs using quantitative susceptibility maps, which were classified into 3 groups:

• Persisting PRLS: those present at baseline and follow up
• Disappearing PRLs: those present at baseline but not at follow up
• Newly appearing PRLs: those emerging at follow up

Statistical analyses were conducted to identify associations between PRL type and odds of CDP and PIRA. Researchers also estimated the effect of reducing persisting PRLs and preventing new PRLs on the prevalence of CDP and PIRA.

• The number of persisting PRLs was found to be significantly associated with increased odds of CDP (exp[β], 1.24; P=.047) and increased odds of PIRA occurrence (exp[β], 1.35; P=.011).
• Presence of newly appearing PRLs were significantly associated with increased odds of PIRA occurrence (exp[β], 8.68; P=.010).
• For participants with at least 1 baseline PRL, reducing all persisting PRLs to 0 would reduce 5-year PIRA and CDP prevalence by a relative 45.6% and 27.1%, respectively.
• Across the entire cohort, preventing all new PRLs was estimated to reduce 5-year PIRA prevalence by a relative 14.0%.

The presented data suggest that reducing and preventing PRLs via inflammation-targeting disease modifying therapies (DMTs) may improve clinical disease and disability outcomes for people with MS.