Functional and Structural MRI Changes Associated With Cognitive Worsening in Multiple Sclerosis: A 3-Year Longitudinal Study (P11-3.003)

Abstract

<h3>Objective:</h3> To apply a multiparametric MRI approach to identify mechanisms associated with cognitive worsening in multiple sclerosis (MS). <h3>Background:</h3> Heterogeneous processes may contribute to cognitive impairment in MS; however, its association with brain structural and functional MRI changes still need to be fully explored. <h3>Design/Methods:</h3> Brain dual-echo, 3D T1-weighted, diffusion-weighted imaging, and resting state (RS) functional MRI scans were acquired at baseline and after median follow up of 3.4 years in 35 MS patients and 22 healthy controls (HC). Associations between cognitive worsening at Rao’s battery and longitudinal changes in T2-hyperintense lesion location, WM microstructural damage, gray matter (GM) atrophy and RS functional connectivity (FC) were explored using tract-based spatial statistic, tensor-based morphometry and independent component analysis. <h3>Results:</h3> Fifteen (43%) MS patients were cognitively impaired at baseline and 10 (29%) showed cognitive deterioration at follow-up. At baseline, compared to HC, MS patients showed widespread WM damage and GM atrophy, and decreased RS FC in some clusters of executive control (ECN) and working memory networks (WMN). At follow-up, annualized volume loss of caudate nucleus was significantly higher in MS patients with vs without cognitive deterioration (−1.2% vs −0.2%, p&lt;0.05). No significant between-group differences in lesion location, WM microstructural changes or GM atrophy were found. Compared to stable MS patients, worsened patients showed decreased RS FC in right hippocampus of right WMN and in right insula of default mode network. In the opposite comparison, increased RS FC in left insula of ECN was found. <h3>Conclusions:</h3> While cognitively-stable MS patients showed increased RS FC in left insula, possibly reflecting a compensatory mechanism, cognitive deterioration in MS patients was associated with decreased RS FC in several functional brain networks, with limited GM atrophy progression. Our study suggests that, in MS patients already characterized by substantial structural damage, cognitive deterioration might be secondary to functional network collapse. <b>Disclosure:</b> Dr. Azzimonti has nothing to disclose. Mr. Preziosa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Bristol Myers Squibb . Mr. Preziosa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Sanofi Genzyme. Mr. Preziosa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Novartis. Mr. Preziosa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Roche. Mr. Preziosa has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Merck. Paola Valsasina has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for ACCMED. Elisabetta Pagani has nothing to disclose. Olga Marchesi has nothing to disclose. Dr. Tedone has nothing to disclose. Carmen Vizzino has nothing to disclose. Dr. Filippi has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Bayer, Biogen Idec, Merck-Serono, Novartis, Roche, Sanofi Genzyme, Takeda, and Teva Pharmaceutical Industries. Dr. Filippi has received personal compensation in the range of $5,000-$9,999 for serving on a Speakers Bureau for Bayer, Biogen Idec, Merck-Serono, Novartis, Roche, Sanofi Genzyme, Takeda, and Teva Pharmaceutical Industries. Dr. Filippi has received personal compensation in the range of $5,000-$9,999 for serving as an Editor, Associate Editor, or Editorial Advisory Board Member for Springer Nature. The institution of Dr. Filippi has received research support from Biogen Idec, Merck-Serono, Novartis, Roche, Teva Pharmaceutical Industries, Italian Ministry of Health, Fondazione Italiana Sclerosi Multipla, and ARiSLA (Fondazione Italiana di Ricerca per la SLA). Maria Assunta Rocca has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for Bayer, Biogen, Bristol Myers Squibb, Celgene, Genzyme, Merck Serono, Novartis, Roche, and Teva. The institution of Maria Assunta Rocca has received research support from Italian Ministry of Health, MS Society of Canada and Fondazione Italiana Sclerosi Multipla.