Article

Association of neocortical volume changes with cognitive deterioration in relapsing-remitting multiple sclerosis

Department of Neurology, University of Florence, Viale Morgagni, 85-50134 Florence, Italy.
JAMA Neurology (Impact Factor: 7.01). 08/2007; 64(8):1157-61. DOI: 10.1001/archneur.64.8.1157
Source: PubMed

ABSTRACT We previously reported selective decreases of neocortical volumes in patients with early relapsing-remitting (RR) multiple sclerosis (MS) with mild cognitive impairment, with a good correlation between cortical volumes and cognitive measures.
To assess the relevance of gray matter changes over time to changes in cognition in RRMS.
A longitudinal survey after 2.5 years. Each patient underwent a magnetic resonance imaging (MRI) protocol identical to that performed at baseline; cognitive performance was reassessed with the Rao Brief Repeatable Battery of Neuropsychological Tests in Multiple Sclerosis.
Two university MS clinics.
Of 41 patients with RRMS who participated in the original cross-sectional study, 28 were available for the follow-up evaluation (18 women; mean +/- SD age, 37.1 +/- 8.9 years; mean +/- SD MS duration, 7.3 +/- 2.9 years; mean +/- SD Expanded Disability Status Scale score, 1.8 +/- 1.5).
We measured the percentage of brain volume changes, normalized cortical volume (NCV) changes, and normalized deep gray matter volume changes on conventional T1-weighted MRIs and changes in lesion load on T2-weighted MRIs. The number of tests failed on the Rao Brief Repeatable Battery were used to classify the patients as cognitively deteriorating or stable or improving.
We identified 12 of 28 cognitively deteriorating and 16 of 28 stable or improving patients. These subgroups did not differ in the mean +/- SD percentage of brain volume changes (-2.1% +/- 1.2% vs -1.3% +/- 1.3%; P = .11), normalized deep gray matter volume changes (-2.1 +/- 2.8 mL vs -0.6 +/- 3.1 mL; P = .60), and changes in lesion load on T2-weighted MRIs (1.9 +/- 2.6 mL vs 1.6 +/- 2.3 mL; P = .73). However, NCV changes were significantly higher in deteriorating than in stable or improving patients (-43.0 +/- 18.9 mL vs -17.8 +/- 26.6 mL; P = .007). In deteriorating patients, NCV changes were correlated with performance in a verbal fluency test (r = 0.73; P < .001). In a regression model, only NCV changes were significantly associated with deteriorating cognitive performance (odds ratio, 0.8; 95% confidence interval, 0.7-0.9).
Progressive neocortical gray matter loss is relevant to MS-associated cognitive impairment and may represent a sensitive marker of deteriorating cognitive performance in RRMS.

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    • "Several authors investigated the role of GM and its association with CI. In a group of RRMS patients, Amato et al. [69] found that cortical atrophy was correlated with a poor performance on NPS testing. In particular neocortical atrophy was associated with impairment in verbal memory, verbal fluency, and attention. "
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    01/2014; 2014:609694. DOI:10.1155/2014/609694
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    • "MS-related cognitive impairment has been consistently associated with brain atrophy also in the earliest disease stages [27], [50], [51], and damage to several GM structures can be associated with impairment of specific cognitive functions [52]. Here we have demonstrated that variants of CNR1 gene have a direct effect on executive functioning measured by WLG test, ST (inhibition of automatic response), D-KEFS Sorting test (verbal/nonverbal modality-specific problem-solving skills, ability to transfer sorting concepts into action and ability to inhibit previous description responses to engage in flexibility of thinking). "
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    PLoS ONE 12/2013; 8(12):e82848. DOI:10.1371/journal.pone.0082848 · 3.23 Impact Factor
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    • "CII is negatively correlated with grey matter volume [32], [33]. However, in TT group of PP-MS patient, the CII and the frequency of CI subjects were not significantly higher respect to CT/CC group (p>0.1 for both comparisons; Fig. 5C,D), a front of a major extent of neuronal damage detected at OCT. PP-MS TT subjects had higher values at PASAT (51.37±9.5 versus 42.65±12.1, "
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