title: Multimodal voxel-based meta-analysis of white matter abnormalities in obsessive-compulsive disorder.
abstract: White matter (WM) abnormalities have long been suspected in obsessive-compulsive disorder (OCD) but the available evidence has been inconsistent. We conducted the first multimodal meta-analysis of WM volume (WMV) and fractional anisotropy (FA) studies in OCD. All voxel-wise studies comparing WMV or FA between patients with OCD and healthy controls in the PubMed, ScienceDirect, Google Scholar, Web of Knowledge and Scopus databases were retrieved. Manual searches were also conducted and authors were contacted soliciting additional data. Thirty-four data sets were identified, of which 22 met inclusion criteria (five of them unpublished; comprising 537 adult and pediatric patients with OCD and 575 matched healthy controls). Whenever possible, raw statistical parametric maps were also obtained from the authors. Peak and raw WMV and FA data were combined using novel multimodal meta-analytic methods implemented in effect-size signed differential mapping. Patients with OCD showed widespread WM abnormalities, but findings were particularly robust in the anterior midline tracts (crossing between anterior parts of cingulum bundle and body of corpus callosum), which showed both increased WMV and decreased FA, possibly suggesting an increase of fiber crossing in these regions. This finding was also observed when the analysis was limited to adult participants, and especially pronounced in samples with a higher proportion of medicated patients. Therefore, patients with OCD may have widespread WM abnormalities, particularly evident in anterior midline tracts, although these changes might be, at least in part, attributable to the effects of therapeutic drugs.
authors.affiliation: 1] Department of Psychosis Studies, Institute of Psychiatry, King's College London, London, UK [2] Research Unit, FIDMAG Germanes Hospitalàries-CIBERSAM, Sant Boi de Llobregat, Barcelona, Spain.
authors.forename: Joaquim
authors.identifier: 0000000312405438
authors.initials: J
authors.lastname: Radua
authors.affiliation: 1] Department of Psychosis Studies, Institute of Psychiatry, King's College London, London, UK [2] Westminster and Kensington and Chelsea Early Intervention in Psychosis Team, Central North West London NHS Trust, London, UK.
authors.forename: Mar
authors.initials: M
authors.lastname: Grau
authors.affiliation: Department of Psychiatry and Department of Anatomy and Neurosciences, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Odile A
authors.initials: OA
authors.lastname: van den Heuvel
authors.affiliation: 1] Natbrainlab-Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, King's College London, London, UK [2] UMR_S 975-CNRS UMR 7225, Centre de Recherche de l'Institut du Cerveau et de la Moelle épinière, Groupe Hospitalier Pitié-Salpêtrière, Paris, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Thiebaut de Schotten
authors.affiliation: Department of Psychiatry and Mental Health, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
authors.forename: Dan J
authors.initials: DJ
authors.lastname: Stein
authors.affiliation: Research Unit, FIDMAG Germanes Hospitalàries-CIBERSAM, Sant Boi de Llobregat, Barcelona, Spain.
authors.forename: Erick J
authors.initials: EJ
authors.lastname: Canales-Rodríguez
authors.affiliation: Natbrainlab-Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, King's College London, London, UK.
authors.forename: Marco
authors.initials: M
authors.lastname: Catani
authors.affiliation: 1] Department of Psychosis Studies, Institute of Psychiatry, King's College London, London, UK [2] Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
authors.forename: David
authors.initials: D
authors.lastname: Mataix-Cols
mesh_terms: D016880:Anisotropy; D001931:Brain Mapping; D016208:Databases, Factual / Q000706:statistics & numerical data; D056324:Diffusion Tensor Imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted; D009771:Obsessive-Compulsive Disorder / Q000473:pathology*; D066127:White Matter / Q000473:pathology*