Chris H. Polman
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Research Interests
Chris H. Polman has a total of 192 co-authors. Here are the top co-authors by number of shared publications:
- Frederik Barkhof
Amsterdam UMC, Location VUmc
9 shared publications - Alan J. Thompson
Queen Square Multiple Sclerosis Centre, Department of Neuroinflammation, UCL Institute of Neurology, London, United Kingdom
7 shared publications - Bernard M. J. Uitdehaag
VU University Medical Center, Amsterdam, The Netherlands
7 shared publications - Ludwig Kappos
University Hospital Basel, Switzerland
5 shared publications L. Kappos
4 shared publications- Xavier Montalban
Centro de Esclerosis Múltiple de Cataluña y Departamento de Neurología, Hospital Universitario Vall d’Hebron, 08035 Barcelona, España
4 shared publications
Latest Publications
- Open Access
- 12 January 2014
- Published by Springer Nature in Journal of Neurology
- Vol. 261 (3) , 490-499
Patient subgroup analyses of the treatment effect of subcutaneous interferon β-1a on development of multiple sclerosis in the randomized controlled REFLEX study
The REFLEX study (NCT00404352) established that subcutaneous (sc) interferon (IFN) β-1a reduced the risks of McDonald MS (2005 criteria) and clinically definite multiple sclerosis (CDMS) in patients with a first clinical demyelinating event suggestive of MS. The aim of this subgroup analysis was to assess the treatment effect of sc IFN β-1a in patient subgroups defined by baseline disease and demographic characteristics (age, sex, use of steroids at the first event, classification of first event as mono- or multifocal, presence/absence of gadolinium-enhancing lesions, count of <9 or ≥9 T2 lesions), and by diagnosis of MS using the revised McDonald 2010 MS criteria. Patients were randomized to the serum-free formulation of IFN β-1a, 44 μg sc three times weekly or once weekly, or placebo, for 24 months or until diagnosis of CDMS. Treatment effects of sc IFN β-1a on McDonald 2005 MS and CDMS in the predefined subgroups were similar to effects found in the intent-to-treat population. McDonald 2010 MS was retrospectively diagnosed in 37.7 % of patients at baseline. Both regimens of sc IFN β-1a significantly reduced the risk versus placebo of McDonald 2005 MS and CDMS, irrespective of McDonald 2010 status at baseline (risk reductions between 29 and 51 %). The effect of sc IFN β-1a was not substantially influenced by baseline patient demographic and disease characteristics, or baseline presence/absence of McDonald 2010 MS.
- 12 January 2014
- Published by Springer Nature in Journal of Neurology
- Vol. 261 (3) , 490-499
Open AccessPatient subgroup analyses of the treatment effect of subcutaneous interferon β-1a on development of multiple sclerosis in the randomized controlled REFLEX study
The REFLEX study (NCT00404352) established that subcutaneous (sc) interferon (IFN) β-1a reduced the risks of McDonald MS (2005 criteria) and clinically definite multiple sclerosis (CDMS) in patients with a first clinical demyelinating event suggestive of MS. The aim of this subgroup analysis was to assess the treatment effect of sc IFN β-1a in patient subgroups defined by baseline disease and demographic characteristics (age, sex, use of steroids at the first event, classification of first event as mono- or multifocal, presence/absence of gadolinium-enhancing lesions, count of <9 or ≥9 T2 lesions), and by diagnosis of MS using the revised McDonald 2010 MS criteria. Patients were randomized to the serum-free formulation of IFN β-1a, 44 μg sc three times weekly or once weekly, or placebo, for 24 months or until diagnosis of CDMS. Treatment effects of sc IFN β-1a on McDonald 2005 MS and CDMS in the predefined subgroups were similar to effects found in the intent-to-treat population. McDonald 2010 MS was retrospectively diagnosed in 37.7 % of patients at baseline. Both regimens of sc IFN β-1a significantly reduced the risk versus placebo of McDonald 2005 MS and CDMS, irrespective of McDonald 2010 status at baseline (risk reductions between 29 and 51 %). The effect of sc IFN β-1a was not substantially influenced by baseline patient demographic and disease characteristics, or baseline presence/absence of McDonald 2010 MS.
- 1 November 2013
- Published by Radiological Society of North America (RSNA) in Radiology
- Vol. 269 (2) , 542-552
Relevance of Spinal Cord Abnormalities to Clinical Disability in Multiple Sclerosis: MR Imaging Findings in a Large Cohort of Patients
Purpose To determine whether spinal cord atrophy differs among disease subtypes in multiple sclerosis (MS) and whether it offers diagnostic and clinical correlative information beyond that provided by other magnetic resonance (MR) imaging markers. Materials and Methods The institutional review board approved the study; all subjects gave written informed consent. Upper cervical cord cross-sectional area (UCCA), brain and spinal cord lesion loads, and brain atrophy were measured in 440 patients with MS (311 with relapsing-remitting [RR] MS, 92 with secondary-progressive [SP] MS, and 37 with primary-progressive [PP] MS) studied in two centers. Disability was scored with the Expanded Disability Status Scale (EDSS), the timed 25-foot walk test (TWT), and the nine-hole peg test. UCCA was compared between groups with the Mann-Whitney U test. Correlations were assessed with the Spearman ρ test. Multivariate associations between UCCA and clinical and other MR imaging parameters, including number of hypointense brain lesions on T1-weighted MR images, presence of diffuse abnormalities, and number of involved segments in the spinal cord, were assessed by using multiple linear regression, adjusted for study center site. Results The UCCA in patients with SP MS (median, 79 mm2; interquartile range, 72.4–84.9 mm2) and PP MS (median, 77.3 mm2; interquartile range, 69–82.5 mm2) was significantly smaller (P < .001) than that in patients with RR MS (median, 84 mm2; interquartile range, 78.7–89.3 mm2). UCCA was inversely correlated with EDSS score, TWT, and nine-hole peg test findings (ρ ≤ −0.29, P < .001 for all comparisons). UCCA, number of hypointense brain lesions on T1-weighted MR images, presence of diffuse abnormalities, and number of involved segments in the spinal cord were found to be significant explanatory factors for clinical disability (R2 = 0.564). The UCCA and the number of hypointense brain lesions on T1-weighted images were the strongest MR imaging parameters for explaining physical disability, as measured with the EDSS. Conclusion Spinal cord abnormalities have a strong effect on clinical disability in MS. MR imaging–derived UCCA was found to be the most significant spinal cord parameter for explaining EDSS score. © RSNA, 2013
- 1 November 2013
- Published by Radiological Society of North America (RSNA) in Radiology
- Vol. 269 (2) , 542-552
Relevance of Spinal Cord Abnormalities to Clinical Disability in Multiple Sclerosis: MR Imaging Findings in a Large Cohort of Patients
Purpose To determine whether spinal cord atrophy differs among disease subtypes in multiple sclerosis (MS) and whether it offers diagnostic and clinical correlative information beyond that provided by other magnetic resonance (MR) imaging markers. Materials and Methods The institutional review board approved the study; all subjects gave written informed consent. Upper cervical cord cross-sectional area (UCCA), brain and spinal cord lesion loads, and brain atrophy were measured in 440 patients with MS (311 with relapsing-remitting [RR] MS, 92 with secondary-progressive [SP] MS, and 37 with primary-progressive [PP] MS) studied in two centers. Disability was scored with the Expanded Disability Status Scale (EDSS), the timed 25-foot walk test (TWT), and the nine-hole peg test. UCCA was compared between groups with the Mann-Whitney U test. Correlations were assessed with the Spearman ρ test. Multivariate associations between UCCA and clinical and other MR imaging parameters, including number of hypointense brain lesions on T1-weighted MR images, presence of diffuse abnormalities, and number of involved segments in the spinal cord, were assessed by using multiple linear regression, adjusted for study center site. Results The UCCA in patients with SP MS (median, 79 mm2; interquartile range, 72.4–84.9 mm2) and PP MS (median, 77.3 mm2; interquartile range, 69–82.5 mm2) was significantly smaller (P < .001) than that in patients with RR MS (median, 84 mm2; interquartile range, 78.7–89.3 mm2). UCCA was inversely correlated with EDSS score, TWT, and nine-hole peg test findings (ρ ≤ −0.29, P < .001 for all comparisons). UCCA, number of hypointense brain lesions on T1-weighted MR images, presence of diffuse abnormalities, and number of involved segments in the spinal cord were found to be significant explanatory factors for clinical disability (R2 = 0.564). The UCCA and the number of hypointense brain lesions on T1-weighted images were the strongest MR imaging parameters for explaining physical disability, as measured with the EDSS. Conclusion Spinal cord abnormalities have a strong effect on clinical disability in MS. MR imaging–derived UCCA was found to be the most significant spinal cord parameter for explaining EDSS score. © RSNA, 2013
- 9 September 2013
- Published by Elsevier in Journal of the Neurological Sciences
- Vol. 334 (1-2) , 143-147
Analyzing differences between patient and proxy on Patient Reported Outcomes in multiple sclerosis
- 9 September 2013
- Published by Elsevier in Journal of the Neurological Sciences
- Vol. 334 (1-2) , 143-147
Analyzing differences between patient and proxy on Patient Reported Outcomes in multiple sclerosis
- Open Access
- 11 September 2012
- Published by Springer Nature in BMC Psychiatry
- Vol. 12 (1) , 1-8
Internet-based self-help treatment for depression in multiple sclerosis: study protocol of a randomized controlled trial
Depression in MS patients is frequent but often not treated adequately. An important underlying factor may be physical limitations that preclude face-to-face contact. Internet-based treatment showed to be effective for depressive symptoms in general and could thus be a promising tool for treatment in MS. Here, we present a study protocol to investigate the effectiveness of a 5 week Internet-based self-help problem solving treatment (PST) for depressive symptoms in MS patients in a randomized controlled trial. We aim to include 166 MS patients with moderate to severe depressive symptoms who will be randomly assigned to an Internet-based intervention (with or without supportive text-messages) or waiting list control group. The primary outcome is the change in depressive symptoms defined by a change in the sum score on the Beck Depression Inventory (BDI-II). Secondary outcomes will include measures of anxiety, fatigue, cognitive functioning, physical and psychological impact of MS, quality of life, problem solving skills, social support, mastery, satisfaction and compliance rate. Assessments will take place at baseline (T0), within a week after the intervention (T1), at four months (T2) and at ten months follow-up (T3: only the intervention group). The control group will be measured at the same moments in time. Analysis will be based on the intention-to-treat principle. If shown to be effective, Internet-based PST will offer new possibilities to reach and treat MS patients with depressive symptoms and to improve the quality of care. The Dutch Cochrane Center, NTR2772
- 11 September 2012
- Published by Springer Nature in BMC Psychiatry
- Vol. 12 (1) , 1-8
Open AccessInternet-based self-help treatment for depression in multiple sclerosis: study protocol of a randomized controlled trial
Depression in MS patients is frequent but often not treated adequately. An important underlying factor may be physical limitations that preclude face-to-face contact. Internet-based treatment showed to be effective for depressive symptoms in general and could thus be a promising tool for treatment in MS. Here, we present a study protocol to investigate the effectiveness of a 5 week Internet-based self-help problem solving treatment (PST) for depressive symptoms in MS patients in a randomized controlled trial. We aim to include 166 MS patients with moderate to severe depressive symptoms who will be randomly assigned to an Internet-based intervention (with or without supportive text-messages) or waiting list control group. The primary outcome is the change in depressive symptoms defined by a change in the sum score on the Beck Depression Inventory (BDI-II). Secondary outcomes will include measures of anxiety, fatigue, cognitive functioning, physical and psychological impact of MS, quality of life, problem solving skills, social support, mastery, satisfaction and compliance rate. Assessments will take place at baseline (T0), within a week after the intervention (T1), at four months (T2) and at ten months follow-up (T3: only the intervention group). The control group will be measured at the same moments in time. Analysis will be based on the intention-to-treat principle. If shown to be effective, Internet-based PST will offer new possibilities to reach and treat MS patients with depressive symptoms and to improve the quality of care. The Dutch Cochrane Center, NTR2772
- 29 April 2011
- Published by Wiley in Annals of Neurology
- Vol. 70 (1) , 183-184
Reply
- Open Access
- 24 February 2011
- Published by Springer Nature in Genes & Immunity
- Vol. 12 (5) , 335-340
A knowledge-driven interaction analysis reveals potential neurodegenerative mechanism of multiple sclerosis susceptibility
Gene–gene interactions are proposed as an important component of the genetic architecture of complex diseases, and are just beginning to be evaluated in the context of genome-wide association studies (GWAS). In addition to detecting epistasis, a benefit to interaction analysis is that it also increases power to detect weak main effects. We conducted a knowledge-driven interaction analysis of a GWAS of 931 multiple sclerosis (MS) trios to discover gene–gene interactions within established biological contexts. We identify heterogeneous signals, including a gene–gene interaction between CHRM3 (muscarinic cholinergic receptor 3) and MYLK (myosin light-chain kinase) (joint P=0.0002), an interaction between two phospholipase C-β isoforms, PLCβ1 and PLCβ4 (joint P=0.0098), and a modest interaction between ACTN1 (actinin alpha 1) and MYH9 (myosin heavy chain 9) (joint P=0.0326), all localized to calcium-signaled cytoskeletal regulation. Furthermore, we discover a main effect (joint P=5.2E−5) previously unidentified by single-locus analysis within another related gene, SCIN (scinderin), a calcium-binding cytoskeleton regulatory protein. This work illustrates that knowledge-driven interaction analysis of GWAS data is a feasible approach to identify new genetic effects. The results of this study are among the first gene–gene interactions and non-immune susceptibility loci for MS. Further, the implicated genes cluster within inter-related biological mechanisms that suggest a neurodegenerative component to MS.
- 24 February 2011
- Published by Springer Nature in Genes & Immunity
- Vol. 12 (5) , 335-340
Open AccessA knowledge-driven interaction analysis reveals potential neurodegenerative mechanism of multiple sclerosis susceptibility
Gene–gene interactions are proposed as an important component of the genetic architecture of complex diseases, and are just beginning to be evaluated in the context of genome-wide association studies (GWAS). In addition to detecting epistasis, a benefit to interaction analysis is that it also increases power to detect weak main effects. We conducted a knowledge-driven interaction analysis of a GWAS of 931 multiple sclerosis (MS) trios to discover gene–gene interactions within established biological contexts. We identify heterogeneous signals, including a gene–gene interaction between CHRM3 (muscarinic cholinergic receptor 3) and MYLK (myosin light-chain kinase) (joint P=0.0002), an interaction between two phospholipase C-β isoforms, PLCβ1 and PLCβ4 (joint P=0.0098), and a modest interaction between ACTN1 (actinin alpha 1) and MYH9 (myosin heavy chain 9) (joint P=0.0326), all localized to calcium-signaled cytoskeletal regulation. Furthermore, we discover a main effect (joint P=5.2E−5) previously unidentified by single-locus analysis within another related gene, SCIN (scinderin), a calcium-binding cytoskeleton regulatory protein. This work illustrates that knowledge-driven interaction analysis of GWAS data is a feasible approach to identify new genetic effects. The results of this study are among the first gene–gene interactions and non-immune susceptibility loci for MS. Further, the implicated genes cluster within inter-related biological mechanisms that suggest a neurodegenerative component to MS.
- Open Access
- 18 January 2011
- Published by Springer Nature in Genome Medicine
- Vol. 3 (1) , 3
Modeling the cumulative genetic risk for multiple sclerosis from genome-wide association data
Background: Multiple sclerosis (MS) is the most common cause of chronic neurologic disability beginning in early to middle adult life. Results from recent genome-wide association studies (GWAS) have substantially lengthened the list of disease loci and provide convincing evidence supporting a multifactorial and polygenic model of inheritance. Nevertheless, the knowledge of MS genetics remains incomplete, with many risk alleles still to be revealed. Methods: We used a discovery GWAS dataset (8,844 samples, 2,124 cases and 6,720 controls) and a multi-step logistic regression protocol to identify novel genetic associations. The emerging genetic profile included 350 independent markers and was used to calculate and estimate the cumulative genetic risk in an independent validation dataset (3,606 samples). Analysis of covariance (ANCOVA) was implemented to compare clinical characteristics of individuals with various degrees of genetic risk. Gene ontology and pathway enrichment analysis was done using the DAVID functional annotation tool, the GO Tree Machine, and the Pathway-Express profiling tool. Results: In the discovery dataset, the median cumulative genetic risk (P-Hat) was 0.903 and 0.007 in the case and control groups, respectively, together with 79.9% classification sensitivity and 95.8% specificity. The identified profile shows a significant enrichment of genes involved in the immune response, cell adhesion, cell communication/signaling, nervous system development, and neuronal signaling, including ionotropic glutamate receptors, which have been implicated in the pathological mechanism driving neurodegeneration. In the validation dataset, the median cumulative genetic risk was 0.59 and 0.32 in the case and control groups, respectively, with classification sensitivity 62.3% and specificity 75.9%. No differences in disease progression or T2-lesion volumes were observed among four levels of predicted genetic risk groups (high, medium, low, misclassified). On the other hand, a significant difference (F = 2.75, P = 0.04) was detected for age of disease onset between the affected misclassified as controls (mean = 36 years) and the other three groups (high, 33.5 years; medium, 33.4 years; low, 33.1 years). Conclusions: The results are consistent with the polygenic model of inheritance. The cumulative genetic risk established using currently available genome-wide association data provides important insights into disease heterogeneity and completeness of current knowledge in MS genetics.
- 18 January 2011
- Published by Springer Nature in Genome Medicine
- Vol. 3 (1) , 3
Open AccessModeling the cumulative genetic risk for multiple sclerosis from genome-wide association data
Background: Multiple sclerosis (MS) is the most common cause of chronic neurologic disability beginning in early to middle adult life. Results from recent genome-wide association studies (GWAS) have substantially lengthened the list of disease loci and provide convincing evidence supporting a multifactorial and polygenic model of inheritance. Nevertheless, the knowledge of MS genetics remains incomplete, with many risk alleles still to be revealed. Methods: We used a discovery GWAS dataset (8,844 samples, 2,124 cases and 6,720 controls) and a multi-step logistic regression protocol to identify novel genetic associations. The emerging genetic profile included 350 independent markers and was used to calculate and estimate the cumulative genetic risk in an independent validation dataset (3,606 samples). Analysis of covariance (ANCOVA) was implemented to compare clinical characteristics of individuals with various degrees of genetic risk. Gene ontology and pathway enrichment analysis was done using the DAVID functional annotation tool, the GO Tree Machine, and the Pathway-Express profiling tool. Results: In the discovery dataset, the median cumulative genetic risk (P-Hat) was 0.903 and 0.007 in the case and control groups, respectively, together with 79.9% classification sensitivity and 95.8% specificity. The identified profile shows a significant enrichment of genes involved in the immune response, cell adhesion, cell communication/signaling, nervous system development, and neuronal signaling, including ionotropic glutamate receptors, which have been implicated in the pathological mechanism driving neurodegeneration. In the validation dataset, the median cumulative genetic risk was 0.59 and 0.32 in the case and control groups, respectively, with classification sensitivity 62.3% and specificity 75.9%. No differences in disease progression or T2-lesion volumes were observed among four levels of predicted genetic risk groups (high, medium, low, misclassified). On the other hand, a significant difference (F = 2.75, P = 0.04) was detected for age of disease onset between the affected misclassified as controls (mean = 36 years) and the other three groups (high, 33.5 years; medium, 33.4 years; low, 33.1 years). Conclusions: The results are consistent with the polygenic model of inheritance. The cumulative genetic risk established using currently available genome-wide association data provides important insights into disease heterogeneity and completeness of current knowledge in MS genetics.
- Top Cited PapersOpen Access
- 11 January 2011
- Published by Wiley in Annals of Neurology
- Vol. 69 (2) , 292-302
Diagnostic criteria for multiple sclerosis: 2010 Revisions to the McDonald criteria
New evidence and consensus has led to further revision of the McDonald Criteria for diagnosis of multiple sclerosis. The use of imaging for demonstration of dissemination of central nervous system lesions in space and time has been simplified, and in some circumstances dissemination in space and time can be established by a single scan. These revisions simplify the Criteria, preserve their diagnostic sensitivity and specificity, address their applicability across populations, and may allow earlier diagnosis and more uniform and widespread use. Ann Neurol 2011
- 11 January 2011
- Published by Wiley in Annals of Neurology
- Vol. 69 (2) , 292-302
Top Cited PapersOpen AccessDiagnostic criteria for multiple sclerosis: 2010 Revisions to the McDonald criteria
New evidence and consensus has led to further revision of the McDonald Criteria for diagnosis of multiple sclerosis. The use of imaging for demonstration of dissemination of central nervous system lesions in space and time has been simplified, and in some circumstances dissemination in space and time can be established by a single scan. These revisions simplify the Criteria, preserve their diagnostic sensitivity and specificity, address their applicability across populations, and may allow earlier diagnosis and more uniform and widespread use. Ann Neurol 2011
- 1 July 2010
- Published by Elsevier in The Lancet Neurology
- Vol. 9 (7) , 740-750
Recommendations for clinical use of data on neutralising antibodies to interferon-beta therapy in multiple sclerosis
- 1 July 2010
- Published by Elsevier in The Lancet Neurology
- Vol. 9 (7) , 740-750
Recommendations for clinical use of data on neutralising antibodies to interferon-beta therapy in multiple sclerosis