Relapsing MS patients exhibit accelerated brain atrophy

Relapsing MS patients, as well as those with disability progression independent of relapse activity, experienced increased brain atrophy, specifically in the cerebral cortex, researchers reported in JAMA Neurology.

Alessandro Cagol, MD, of the department of biomedical engineering at the University of Basel in Switzerland, and colleagues conducted an observational, longitudinal cohort study to determine whether disability progression independent of relapse activity (PIRA) in patients with relapsing MS is associated with accelerated brain tissue loss.

They acquired data from January 2012 through Sept. 2019 from a consortium of tertiary university and non-university referral hospitals and included patients who had regular clinical follow-ups and at least two MRI scans deemed suitable for volumetric analysis.

A total of 1,904 MRI scans from 516 patients with relapsing MS were included (mean age, 41.4 years; 67.4% women; median Expanded Disability Status score, 2.0).

Researchers reported that radiological inflammatory activity was associated with increased atrophy rates in several brain compartments, while an increased annualized relapse rate was linked to accelerated deep gray matter volume loss. When compared with stable patients, those with PIRA had an increased rate of brain volume loss [mean difference in annual percentage change (MD-APC), –0.36; 95% CI, –0.60 to –0.12), which was mainly driven by grey matter loss in the cerebral cortex.

When compared with stable patients, those with relapsing MS had increased whole brain atrophy (MD-APC, –0.18; 95% CI, –0.34 to –0.02), with accelerated grey matter loss in the cerebral cortex.

“Our data show that events of insidious PIRA are associated with increased atrophy rates, likely reflecting ongoing diffuse neurodegenerative processes, especially in cortical [grey matter],” the authors wrote. “These results point to the need to promptly identify patients with PIRA in clinical practice, because they may benefit from optimized therapeutic regimens.”