title: Cognitive impairment and magnetic resonance imaging correlates in primary progressive multiple sclerosis.
abstract: OBJECTIVE
  To characterize cognitive impairment in primary progressive multiple sclerosis (PPMS) and to correlate the pattern of cognitive deficits with brain magnetic resonance imaging (MRI) volumetric data.
  
  
  METHODS
  In a multicenter cross-sectional study, we recruited consecutive patients with PPMS as well as age, sex, and education level-matched healthy controls (HC). All participants underwent neuropsychological (NP) assessment, and brain MRI was performed in patients with PPMS for analysis of lesion load, subcortical GM volumes, and regional cortical volumes.
  
  
  RESULTS
  We recruited 55 patients with PPMS and 36 HC. Thirty-six patients were included in the MRI analysis. Patients with PPMS performed significantly worse than HC in all NP tests. Subcortical GM volume was significantly correlated with all NP tests, except for Stroop Test, with the largest effect for the thalamus (r=-.516 [BVMT-R DR, P=.016 FDR-corrected] to r=.664 [SDMT, P<.001 FDR-corrected]). In the stepwise linear regression model, thalamic volume was the only predictor of performance in all NP tests.
  
  
  CONCLUSIONS
  Cognitive impairment is common in PPMS and affects all evaluated cognitive domains. Subcortical GM volume, particularly of the thalamus, is a strong predictor of cognitive performance, suggesting it has a central role in the pathophysiology of PPMS-related cognitive dysfunction.
authors: Department of Neurology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors: A
authors: A
authors: Gouveia
authors: Department of Neurology, Centro Hospitalar de Lisboa Central, Lisboa, Portugal.
authors: S P
authors: SP
authors: Dias
authors: Department of Neurology, Centro Hospitalar Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal.
authors: T
authors: T
authors: Santos
authors: Department of Neurology, Centro Hospitalar de São João, Porto, Portugal.|Faculty of Medicine, Department of Clinical Neuroscience and Mental Health, University of Porto, Porto, Portugal.
authors: H
authors: H
authors: Rocha
authors: Department of Neurology, Centro Hospitalar de Setúbal, Setúbal, Portugal.
authors: C R
authors: CR
authors: Coelho
authors: Department of Neurology, Centro Hospitalar Entre Douro e Vouga, Santa Maria da Feira, Portugal.|EPIUnit - Epidemiology Research Unit, Institute of Public Health, University of Porto, Porto, Portugal.
authors: L
authors: L
authors: Ruano
authors: Department of Neuroradiology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.
authors: O
authors: O
authors: Galego
authors: Department of Neuroradiology, Centro Hospitalar de Lisboa Central, Lisboa, Portugal.
authors: M C
authors: MC
authors: Diogo
authors: Department of Imaging Diagnosis, Centro Hospitalar de Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal.|Faculty of Medicine, Department of Experimental Biology, Porto University, Porto, Portugal.
authors: D
authors: D
authors: Seixas
authors: Department of Neurology, Centro Hospitalar de São João, Porto, Portugal.|Faculty of Health Sciences, University Fernando Pessoa, Porto, Portugal.
authors: M J
authors: MJ
authors: Sá
authors: Department of Neurology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.|Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors: S
authors: S
authors: Batista
mesh_terms: D000328:Adult; D060825:Cognitive Dysfunction / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000523:psychology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D020528:Multiple Sclerosis, Chronic Progressive / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000523:psychology*; D009483:Neuropsychological Tests; D013788:Thalamus / Q000000981:diagnostic imaging
keywords: cognitive impairment; magnetic resonance imaging; primary progressive multiple sclerosis; subcortical gray matter; thalamus