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Henry A, Stefaniak N, Schmid F, Kwiatkowski A, Hautecoeur P, Lenne B. Assessing cognitive changes in multiple sclerosis: criteria for a reliable decision. J Clin Exp Neuropsychol 2023; 45:321-344. [PMID: 37405367 DOI: 10.1080/13803395.2023.2232122] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 06/16/2023] [Accepted: 06/26/2023] [Indexed: 07/06/2023]
Abstract
INTRODUCTION Quantifying a significant cognitive change on a neuropsychological battery is essential to assess patients' decline or recovery and offer appropriate care. The reliability of change indices is particularly important in multiple sclerosis (MS), as the course of cognitive impairment is quite unpredictable, due at least in part to substantial interindividual variability. The main objective of this study was to compare six different methods for assessing cognitive change in an MS sample: the SD method, two reliable change indices, two standardized regression-based methods (SRB), and the generalized regression-based method (GSRB). METHOD One hundred and twenty-three patients with clinically definite MS and 89 healthy controls underwent a battery of standardized neuropsychological tests assessing cognitive functions that are frequently affected in this disease (i.e., verbal episodic memory, working memory, processing speed and verbal fluency). RESULTS We observed fairly similar proportions of improvement, decline or stability in the control group whatever the method. By contrast, in the MS sample, regression-based methods with one predictor (i.e., score at T1) and four predictors (i.e., score at T1 and demographic factors: age, sex, education level) detected a significant worsening more often than the reliable change indices while the GSRB method was more consistent with the RCI methods in tasks associated with ceiling effects. CONCLUSIONS The interpretation of a patient's cognitive changes depends on which method is used. The (G)SRB methods appear to be relevant indicators for assessing cognitive change in MS. The addition of demographic factors does not seem to play an important role in the prediction of significant worsening in the MS sample, regardless of cognitive domain. For clinicians, an easy-to-use free shiny app is provided.
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Affiliation(s)
- Audrey Henry
- Université de Reims Champagne-Ardenne, Laboratoire Cognition, Santé et Société (C2S), Reims, France
- Department of Psychiatry, Reims University Hospital, EPSMM, Reims, France
| | - Nicolas Stefaniak
- Université de Reims Champagne-Ardenne, Laboratoire Cognition, Santé et Société (C2S), Reims, France
| | - Franca Schmid
- Université de Reims Champagne-Ardenne, Laboratoire Cognition, Santé et Société (C2S), Reims, France
| | - Arnaud Kwiatkowski
- Faculté des Sciences Humaines et Sociales (Institut Catholique de Lille), Groupement des hôpitaux de l'Institut Catholique de Lille - Service de Neurologie - Hôpital St Vincent de Paul, Lille, France
| | - Patrick Hautecoeur
- Faculté des Sciences Humaines et Sociales (Institut Catholique de Lille), Groupement des hôpitaux de l'Institut Catholique de Lille - Service de Neurologie - Hôpital St Vincent de Paul, Lille, France
| | - Bruno Lenne
- Faculté des Sciences Humaines et Sociales (Institut Catholique de Lille), Groupement des hôpitaux de l'Institut Catholique de Lille - Service de Neurologie - Hôpital St Vincent de Paul, Lille, France
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De Somma E, O'Mahony J, Brown RA, Brooks BL, Yeh EA, Cardenas de La Parra A, Arnold D, Collins DL, Maranzano J, Narayanan S, Marrie RA, Bar-Or A, Banwell B, Till C. Disrupted cognitive development following pediatric acquired demyelinating syndromes: a longitudinal study. Child Neuropsychol 2021; 28:649-670. [PMID: 34872458 DOI: 10.1080/09297049.2021.2002289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Long-term cognitive deficits have been observed in some children who experience an acquired demyelinating syndrome (ADS). We examined changes in cognitive functioning over the first two years following incident ADS andtested whether normalized brain and thalamic volume accounted for decline over time. Twenty-five youth (mean age 12.8 years) with ADS, 9 of whom were diagnosed with multiple sclerosis (MS) and 16 of whom experienced monophasic ADS (monoADS), underwent two neuropsychological evaluationsand MRI scans at approximately6- and 24-months post ADS-onset. We examined changes in cognitive outcomes over time and between patient groups. Generalized linear mixed-effect regression models were used to examine the association of normalized brain and thalamic volumesbetween the two timepointswith cognitive z-scores. Cognitive performance was within the age-expected range for both groups and remained stable over time on 15 measures. In the combined sample of monoADS and MS patients, declines (p < .05) were noted on the Symbol Digit Modalities Test (SDMT), the Auditory Working Memory (AWM), and the WJ-III Visual Matching (VisMat)tests, but did not survive FDR correction. Clinically significant declines, as measured by the Reliable Change Index, were observed on the SDMT,AWM, and VisMattests by 19, 42, and 32%, respectively. Lower normalized brain volume at 6-months predicted a negative change in SDMT (B = 0.45, 95%CI: 0.07,0.83) and AWM (B = 0.30, 95%CI: 0.13, 0.47). Chronicity of demyelination is not required for cognitive decline nor for reduced brain volume, suggesting that even a single demyelinating event may negatively impact cognitive potential in children.
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Affiliation(s)
| | - Julia O'Mahony
- Neurosciences and Mental Health, Hospital for Sick Children, Canada Hospital for Sick Children, Toronto, Canada
| | | | - Brian L Brooks
- Neurosciences Program, Alberta Children's Hospital, Calgary, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Canada.,Departments of Pediatrics, Clinical Neurosciences, and Psychology, University of Calgary, Calgary, Canada
| | - E Ann Yeh
- Neurosciences and Mental Health, Hospital for Sick Children, Canada Hospital for Sick Children, Toronto, Canada.,Department of Neurology, Hospital for Sick Children, Toronto, Canada
| | | | - Douglas Arnold
- McConnell Brain Imaging Centre, McGill University, Montreal, Canada
| | - D Louis Collins
- McConnell Brain Imaging Centre, McGill University, Montreal, Canada
| | | | - Sridar Narayanan
- McConnell Brain Imaging Centre, McGill University, Montreal, Canada
| | - Ruth Ann Marrie
- Departments of Internal Medicine and Community Health Sciences, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada
| | - Amit Bar-Or
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Brenda Banwell
- Children's Hospital of Philadelphia, Departments of Neurology and Pediatrics Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Christine Till
- Department of Psychology, York University, Toronto, Canada.,Neurosciences and Mental Health, Hospital for Sick Children, Canada Hospital for Sick Children, Toronto, Canada
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Emanuel AL, van Duinkerken E, Wattjes MP, Klein M, Barkhof F, Snoek FJ, Diamant M, Eringa EC, IJzerman RG, Serné EH. The presence of cerebral white matter lesions and lower skin microvascular perfusion predicts lower cognitive performance in type 1 diabetes patients with retinopathy but not in healthy controls-A longitudinal study. Microcirculation 2019; 26:e12530. [PMID: 30659710 PMCID: PMC6593465 DOI: 10.1111/micc.12530] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 01/07/2019] [Accepted: 01/15/2019] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Cognitive impairments in type 1 diabetes may result from hyperglycemia-associated cerebral microangiopathy. We aimed to identify cerebral microangiopathy and skin microvascular dysfunction-as a surrogate marker for generalized microvascular function-as predictors of cognitive performance over time. METHODS In this prospective cohort study, 25 type 1 diabetes patients with proliferative retinopathy and 25 matched healthy controls underwent neurocognitive testing at baseline and after follow-up (3.8 ± 0.8 years). At baseline, 1.5-T cerebral magnetic resonance imaging was used to detect WML and cerebral microbleeds. Skin capillary perfusion was assessed by means of capillary microscopy. RESULTS In type 1 diabetes patients, but not in healthy controls, the presence of WML (ß = -0.419; P = 0.037) as well as lower skin capillary perfusion (baseline: ß = 0.753; P < 0.001; peak hyperemia: ß = 0.743; P = 0.001; venous occlusion: ß = 0.675; P = 0.003; capillary recruitment: ß = 0.549; P = 0.022) at baseline was associated with lower cognitive performance over time, independent of age, sex, HbA1c, and severe hypoglycemia. The relationship between WML and lower cognitive performance was significantly reduced after adjusting for capillary perfusion. CONCLUSIONS These data fit the hypothesis that cerebral microangiopathy is a manifestation of generalized microvascular dysfunction, leading to lower cognitive performance.
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Affiliation(s)
- Anna L Emanuel
- Diabetes Center, Department of Internal Medicine, Amsterdam University Medical Center, Amsterdam, The Netherlands.,Department of Internal Medicine, Amstelland Hospital, Amstelveen, The Netherlands
| | - Eelco van Duinkerken
- Diabetes Center, Department of Internal Medicine, Amsterdam University Medical Center, Amsterdam, The Netherlands.,Department of Internal Medicine, Amstelland Hospital, Amstelveen, The Netherlands
| | - Mike P Wattjes
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Center, Amsterdam, The Netherlands.,Department of Diagnostic and Interventional Neuroradiology, Hannover Medical School, Hannover, Germany
| | - Martin Klein
- Department of Medical Psychology, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Frederik Barkhof
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Frank J Snoek
- Department of Medical Psychology, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Michaela Diamant
- Diabetes Center, Department of Internal Medicine, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Etto C Eringa
- Department of Physiology, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Richard G IJzerman
- Diabetes Center, Department of Internal Medicine, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Erik H Serné
- Diabetes Center, Department of Internal Medicine, Amsterdam University Medical Center, Amsterdam, The Netherlands
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van Duinkerken E, Steenwijk MD, Klein M, Barkhof F, Mograbi DC, Diamant M, Snoek FJ, Ijzerman RG. Accelerated executive functions decline and gray matter structural changes in middle-aged type 1 diabetes mellitus patients with proliferative retinopathy. J Diabetes 2018; 10:835-846. [PMID: 29665283 DOI: 10.1111/1753-0407.12773] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Revised: 03/19/2018] [Accepted: 04/11/2018] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND The aim of the present study was to determine trajectories of cognitive and cortical changes over time in middle-aged patients with type 1 diabetes mellitus (T1DM) and proliferative retinopathy. METHODS Twenty-five patients and 25 controls underwent neuropsychological assessment and neuroimaging twice in a mean (±SD) of 3.56 ± 0.65 and 3.94 ± 0.91 years, respectively (P = 0.098). Cognitive assessment included the domains of general cognitive ability, memory, information processing speed, executive functions, attention, and motor and psychomotor speed. Symmetrized percentage change in local cortical thickness, surface area, and volume was determined using the FreeSurfer 6 vertex-wise general linear model method. Analyses were performed uncorrected and corrected for baseline systolic blood pressure and depressive symptoms. RESULTS In patients versus controls, accelerated executive function decline was accompanied by, but not related to, lower left frontal and temporal surface area, left parietal and right frontal thickness, and bilateral frontal and right posterior cingulate volume (family-wise error [FWE]-corrected P < 0.05 for all). In patients, lower executive performance was related to loss of right precuneus surface area (PFWE = 0.005). Higher HbA1c during follow-up was related to executive function decline (r = -0.509, P = 0.016) and loss of left hemisphere surface area (rcorrected analysis = -0.555, P = 0.007). CONCLUSIONS After 3.5 years of follow-up, middle-aged T1DM patients with proliferative retinopathy, mild focal changes in executive functions, and cortical structure were found, which may indicate accelerated aging.
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Affiliation(s)
- Eelco van Duinkerken
- Amsterdam Diabetes Center/Department of Internal Medicine, VU University Medical Center, Amsterdam, The Netherlands
- Department of Medical Psychology, VU University Medical Center, Amsterdam, The Netherlands
- Center for Epilepsy, State Brain Institute Paulo Niemeyer, Rio de Janeiro, Brazil
| | - Martijn D Steenwijk
- Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands
- Department of Physics and Medical Technology, VU University Medical Center, Amsterdam, The Netherlands
| | - Martin Klein
- Department of Medical Psychology, VU University Medical Center, Amsterdam, The Netherlands
| | - Frederik Barkhof
- Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands
| | - Daniel C Mograbi
- Center for Epilepsy, State Brain Institute Paulo Niemeyer, Rio de Janeiro, Brazil
- Department of Psychology, Institute of Psychiatry, Kings College, London, UK
| | - Michaela Diamant
- Amsterdam Diabetes Center/Department of Internal Medicine, VU University Medical Center, Amsterdam, The Netherlands
| | - Frank J Snoek
- Department of Medical Psychology, VU University Medical Center, Amsterdam, The Netherlands
- Department of Medical Psychology, Academic Medical Center, Amsterdam, The Netherlands
| | - Richard G Ijzerman
- Amsterdam Diabetes Center/Department of Internal Medicine, VU University Medical Center, Amsterdam, The Netherlands
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Costa SL, Genova HM, DeLuca J, Chiaravalloti ND. Information processing speed in multiple sclerosis: Past, present, and future. Mult Scler 2016; 23:772-789. [PMID: 27207446 DOI: 10.1177/1352458516645869] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
BACKGROUND Information processing speed (IPS) is a prevalent cognitive impairment in multiple sclerosis (MS). OBJECTIVES This review aims to summarize the methods applied to assess IPS in MS and its theoretical conceptualization. A PubMed search was performed to select articles published between 1 January 2004 and 31 December 2013, resulting in 157 articles included. RESULTS The majority (54%) of studies assessed IPS with heterogeneous samples (several disease courses). Studies often report controlling for presence of other neurological disorders (60.5%), age (58.6%), education (51.6%), alcohol history (47.8%), or use of steroids (39.5%). Potential confounding variables, such as recent relapses (50.3%), history of developmental disorders (19.1%), and visual problems (29.9%), were often neglected. Assessments used to study IPS were heterogeneous (ranging from simple to complex tasks) among the studies under review, with 62 different tasks used. Only 9.6% of articles defined the construct of IPS and 22.3% discussed IPS in relation to a theoretical model. FUTURE DIRECTIONS The challenges for the upcoming decade include clarification of the definition of IPS as well as its theoretical conceptualization and a consensus on assessment. Based on the results obtained, we propose a new theoretical model, the tri-factor model of IPS.
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Affiliation(s)
- Silvana L Costa
- Neuropsychology & Neuroscience Laboratory, Kessler Foundation, West Orange, NJ, USA/Department of Physical Medicine & Rehabilitation, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Helen M Genova
- Neuropsychology & Neuroscience Laboratory, Kessler Foundation, West Orange, NJ, USA/Department of Physical Medicine & Rehabilitation, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - John DeLuca
- Neuropsychology & Neuroscience Laboratory, Kessler Foundation, West Orange, NJ, USA/Department of Physical Medicine & Rehabilitation, Rutgers New Jersey Medical School, Newark, NJ, USA/Department of Neurology, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Nancy D Chiaravalloti
- Neuropsychology & Neuroscience Laboratory, Kessler Foundation, West Orange, NJ, USA/Department of Physical Medicine & Rehabilitation, Rutgers New Jersey Medical School, Newark, NJ, USA
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Utz KS, Lee DH, Lämmer A, Waschbisch A, Linker RA, Schenk T. Cognitive functions over the course of 1 year in multiple sclerosis patients treated with disease modifying therapies. Ther Adv Neurol Disord 2016; 9:269-80. [PMID: 27366233 DOI: 10.1177/1756285616643892] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVES Disease-modifying therapies (DMTs) are applied to delay or prevent disease progression in multiple sclerosis (MS). While this has mostly been proven for physical symptoms, available studies regarding long-term effects of DMTs on cognitive functions are rare and sometimes inconsistent due to methodological shortcomings. Particularly in the case of fingolimod, comprehensive data on cognitive functions are not yet available. Therefore, we set out to reliably assess cognitive functions in patients with relapsing-remitting MS (RRMS) treated with DMTs over 1 year. METHODS Cognitive functions were assessed with eight tests at three timepoints: baseline, 6-month follow up and 12-month follow up. First, we investigated whether the stability of cognitive functions (i.e. not falling below the 5% cut-off in more than one test) over 1 year in RRMS patients (n = 41) corresponds to the stability in healthy individuals (n = 40) of a previous study. Second, we compared the percentage of declined and improved patients in the different tests. Third, we compared patients treated with fingolimod (n = 22) with patients treated with natalizumab (n = 11) with regard to cognitive stability. Fourth, based on the patient data, the Reliable Change Index was applied to compute cut-offs for reliable cognitive change. RESULTS Approximately 75% of RRMS patients treated with DMTs remained stable over the course of 1 year. The Paced Auditory Serial Addition Test (PASAT) and the Spatial Recall Test (SPART), produced improvements in 12.5% and 30.6%, respectively, probably due to practice effects. Patients treated with fingolimod did not differ from patients treated with natalizumab with regard to cognitive stability. CONCLUSIONS Cognitive functions remain relatively stable under DMT treatment over 1 year, irrespective of the type of medication. Furthermore, the tests PASAT and SPART should be interpreted cautiously in studies examining performance changes over time. The provided RCI norms may help clinicians to determine whether a difference in two measurements observed in a RRMS patient is reliable.
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Affiliation(s)
- Kathrin S Utz
- Department of Neurology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - De-Hyung Lee
- Department of Neurology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Alexandra Lämmer
- Department of Neurology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Anne Waschbisch
- Department of Neurology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Ralf A Linker
- Department of Neurology, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Thomas Schenk
- Department of Psychology, Ludwig-Maximilians-Universität München, Leopoldstr. 13, 80802 München, Germany
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Wiebenga OT, Schoonheim MM, Hulst HE, Nagtegaal GJA, Strijbis EMM, Steenwijk MD, Polman CH, Pouwels PJW, Barkhof F, Geurts JJG. White Matter Diffusion Changes during the First Year of Natalizumab Treatment in Relapsing-Remitting Multiple Sclerosis. AJNR Am J Neuroradiol 2016; 37:1030-7. [PMID: 26965463 DOI: 10.3174/ajnr.a4690] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 11/12/2015] [Indexed: 01/03/2023]
Abstract
BACKGROUND AND PURPOSE Natalizumab treatment strongly affects relapsing-remitting multiple sclerosis, possibly by restraining white matter damage. This study investigated changes in white matter diffusivity in patients with relapsing-remitting multiple sclerosis during their first year of natalizumab treatment by using diffusion tensor imaging. MATERIALS AND METHODS The study included patients with relapsing-remitting multiple sclerosis initiating natalizumab at baseline (n = 22), patients with relapsing-remitting multiple sclerosis continuing interferon-β or glatiramer acetate (n = 17), and healthy controls (n = 12). Diffusion tensor imaging parameters were analyzed at baseline and month 12. We measured the extent and severity of white matter damage with diffusion tensor imaging parameters such as fractional anisotropy, comparing the patient groups with healthy controls at both time points. RESULTS The extent and severity of white matter damage were reduced significantly in the natalizumab group with time (fractional anisotropy-based extent, 56.8% to 47.2%; severity, z = -0.67 to -0.59; P = .02); this reduction was not observed in the interferon-β/glatiramer acetate group (extent, 41.4% to 39.1%, and severity, z = -0.64 to -0.67; P = .94). Cognitive performance did not change with time in the patient groups but did correlate with the severity of damage (r = 0.53, P = < .001). CONCLUSIONS In patients with relapsing-remitting multiple sclerosis starting natalizumab treatment, the extent and severity of white matter damage were reduced significantly in the first year of treatment. These findings may aid in explaining the large observed clinical effect of natalizumab in relapsing-remitting multiple sclerosis.
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Affiliation(s)
- O T Wiebenga
- From the Departments of Radiology and Nuclear Medicine (O.T.W., G.J.A.N., M.D.S., F.B.) Anatomy and Neurosciences (O.T.W., M.M.S., H.E.H., G.J.A.N., J.J.G.G.)
| | - M M Schoonheim
- Anatomy and Neurosciences (O.T.W., M.M.S., H.E.H., G.J.A.N., J.J.G.G.)
| | - H E Hulst
- Anatomy and Neurosciences (O.T.W., M.M.S., H.E.H., G.J.A.N., J.J.G.G.)
| | - G J A Nagtegaal
- From the Departments of Radiology and Nuclear Medicine (O.T.W., G.J.A.N., M.D.S., F.B.) Anatomy and Neurosciences (O.T.W., M.M.S., H.E.H., G.J.A.N., J.J.G.G.)
| | | | - M D Steenwijk
- From the Departments of Radiology and Nuclear Medicine (O.T.W., G.J.A.N., M.D.S., F.B.)
| | | | - P J W Pouwels
- Physics and Medical Technology (P.J.W.P.), Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, the Netherlands
| | - F Barkhof
- From the Departments of Radiology and Nuclear Medicine (O.T.W., G.J.A.N., M.D.S., F.B.)
| | - J J G Geurts
- Anatomy and Neurosciences (O.T.W., M.M.S., H.E.H., G.J.A.N., J.J.G.G.)
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Fischer M, Kunkel A, Bublak P, Faiss JH, Hoffmann F, Sailer M, Schwab M, Zettl UK, Köhler W. How reliable is the classification of cognitive impairment across different criteria in early and late stages of multiple sclerosis? J Neurol Sci 2014; 343:91-9. [DOI: 10.1016/j.jns.2014.05.042] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Revised: 04/21/2014] [Accepted: 05/19/2014] [Indexed: 01/21/2023]
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