Is impaired information processing speed a matter of structural or functional damage in MS?
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ABSTRACT:
SUBMITTER: Meijer KA
PROVIDER: S-EPMC6169100 | biostudies-literature | 2018
REPOSITORIES: biostudies-literature
Publications
Is impaired information processing speed a matter of structural or functional damage in MS?
Meijer K A KA van Geest Q Q Eijlers A J C AJC Geurts J J G JJG Schoonheim M M MM Hulst H E HE
NeuroImage. Clinical 20180926
<h4>Objective</h4>Cognitive deficits, especially those of information processing speed (IPS), are common in multiple sclerosis (MS), however, the underlying neurobiological mechanisms remain poorly understood. In this study, we examined structural and functional brain changes separately, but also in an integrative manner, in relation to IPS performance.<h4>Methods</h4>IPS was measured using the symbol digit modalities test (SDMT) in 330 MS patients and 96 controls. Patients with IPS impairment ( ...[more]
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Project description:Objectives. To examine relationships between conventional MRI measures and the paced auditory serial addition test (PASAT) and symbol digit modalities test (SDMT). Methods. A systematic literature review was conducted. Included studies had ?30 multiple sclerosis (MS) patients, administered the SDMT or PASAT, and measured T2LV or brain atrophy. Meta-analysis of MRI/information processing speed (IPS) correlations, analysis of MRI/IPS significance tests to account for reporting bias, and binomial testing to detect trends when comparing correlation strengths of SDMT versus PASAT and T2LV versus atrophy were conducted. Results. The 39 studies identified frequently reported only significant correlations, suggesting reporting bias. Direct meta-analysis was only feasible for correlations between SDMT and T2LV (r = -0.45, P < 0.001) and atrophy in patients with mixed-MS subtypes (r = -0.54, P < 0.001). Familywise Holm-Bonferroni testing found that selective reporting was not the source of at least half of significant results reported. Binomial tests (P = 0.006) favored SDMT over PASAT in strength of MRI correlations. Conclusions. A moderate-to-strong correlation exists between impaired IPS and MRI in mixed MS populations. Correlations with MRI were stronger for SDMT than for PASAT. Neither heterogeneity among populations nor reporting bias appeared to be responsible for these findings.
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