Multiple sclerosis disease (MS) subtypes are associated with different patterns of gray matter atrophy (GM), according to study results published in Neurology.
This was a large multicenter study in which researchers recruited patients (n = 398) with MS and healthy controls (n = 170) at 8 centers in Europe from the Magnetic Resonance Imaging in MS Study Consortium (MAGNIMS). The study researchers rated patients at baseline and after one year using magnetic resonance imaging and the Extended Disability Status Scale (EDSS). They quantified GM using a source-based morphometry (SBM) method.
The MS cohort included patients with relapsing-remitting MS (RRMS; n = 226), secondary progressive MS (SPMS; n = 95), primary progressive MS (PPMS; n = 43), and clinically isolated syndrome (CIS; n = 34 )).
After one year, 57 control participants and 144 patients with MS remained in the study. In the MS cohort, 15% had worsening MS with 2 patients transitioning from CIS to RRMS and 3 from RRMS to SPMS. Patients with worsening MS differed significantly by gender (P = 0.01), percentage change in brain volume (P = 0.02), volume of T2 brain lesion (P = 0.04), and baseline EDSS (P = 0.05).
In the SBM analysis, the study researchers identified 26 GM traits among 98 independent components. All components showed significant GM atrophy in the patients with MS compared to the participants in the control group (all P £ 0.036), with the exception of one component in the standard mode network (P = 0.07) and in the frontoparietal network (P = 0 , 11). .
Among the patient subtypes, those with RRMS compared to those with CIS showed greater GM atrophy for a component in the subcortical networks and in the standard mode network (all P £ 0.04). In patients with SPMS compared to patients with PPMS, the results showed increased GM atrophy in subcortical components (all P £ 0.01). In patients with PPMS, GM atrophy of the sensorimotor components was greater than in patients with SPMS (P <0.001).
The GM volume remained stable among participants in the control cohort. However, in the participants in the MS cohort, it progressively decreased in components of the cerebellar, subcortical, sensorimotor, auditory and frontoparietal networks (all P £ 0.04). This pattern was mainly determined by patients with progressive MS subtypes.
A high baseline EDSS value (r2, 0.65) was associated with a lower normalized brain volume (b, -0.13; P = 0.001), an increased GM atrophy in the sensorimotor network (b, -0.12; P = 0.002 ) and a longer duration of illness (b, 0.09; P = 0.04).
This study was limited by the low retention of patients with progressive MS at 1 year, reducing the ability to assess GM atrophy in patients with severe MS phenotypes.
The study authors found that atrophy in cerebellar and sensorimotor GM was associated with clinical deterioration in MS and that different networks of GM atrophy were associated with disease subtypes. The results “showed differential involvement in different GM networks across disease stages that progressed in MS at one year,” while “sensorimotor and cerebellar GM atrophy explained baseline obstruction and clinical deterioration,” they concluded.
Disclosure: Several authors have stated that they are part of the pharmaceutical industry. For a full list of details, see the original article.
Rocca MA, Valsasina P, Meani A. et al. Association of gray matter atrophy patterns with clinical phenotype and progression of multiple sclerosis. Neurology. Published online January 13, 2021. doi: 10.1212 / WNL.0000000000011494