MS Progression Independent of Relapse Activity Associated With Increased Brain Atrophy

Patients with relapsing multiple sclerosis (MS) and disease progression independent of relapse activity (PIRA) showed greater rates of tissue loss in several brain areas compared with patients with clinical stability, according to a study published in JAMA Neurology.

“Our data also indicate that patients with relapsing MS and PIRA are subject to global brain tissue loss similar to that of patients experiencing relapse activity,” researchers wrote.

The observational, longitudinal study included 516 patients with relapsing MS and 1904 brain magnetic resonance imaging scans from the Swiss Multiple Sclerosis Cohort study.

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Researchers identified associations between radiological inflammatory activity and increased atrophy rates in several brain areas, as well as between increased annualized relapse rate and accelerated deep gray matter (GM) volume loss, according to the study.

Compared with patients with clinical stability, patients with PIRA had a faster rate of brain volume loss; researchers reported a mean difference in annual percentage change of −0.36. The loss was mostly driven by GM loss in the cerebral cortex.

Patients who were relapsing showed increased whole brain atrophy compared with patients with clinical stability; the mean difference in annual percentage change was −0.18. The accelerated GM loss occurred in both the cerebral cortex and deep GM, the study found.

Rates of brain atrophy between patients with PIRA and patients presenting with relapse activity did not differ.

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

Reference

Cagol A, Schaedelin S, Barakovic M, et al. Association of brain atrophy with disease progression independent of relapse activity in patients with relapsing multiple sclerosis. JAMA Neurol. 2022;79(7):682-692. doi: 10.1001/jamaneurol.2022.1025