title: Age and gender interactions in white matter of schizophrenia and obsessive compulsive disorder compared to non-psychiatric controls: commonalities across disorders.
abstract: Schizophrenia (SCZ) and obsessive-compulsive disorder (OCD) are psychiatric disorders with abnormalities in white matter structure. These disorders share high comorbidity and family history of OCD is a risk factor for SCZ which suggests some shared neurobiology. White matter was examined using diffusion tensor imaging in relativity large samples of SCZ (N = 48), OCD (N = 38) and non-psychiatric controls (N = 45). Fractional anisotropy (FA) was calculated and tract based spatial statistics were used to compare groups. In a whole brain analysis, SCZ and OCD both showed small FA reductions relative to controls in the corpus callosum. Both SCZ and OCD showed accelerated reductions in FA with age; specifically in the left superior longitudinal fasciculus in OCD, while the SCZ group demonstrated a more widespread pattern of FA reduction. Patient groups did not differ from each other in total FA or age effects in any regions. A general linear model using 13 a-priori regions of interest showed marginal group, group*gender, and group*age interactions. When OCD and SCZ groups were analyzed together, these marginal effects became significant (p < 0.05), suggesting commonalities exist between these patient groups. Overall, our results demonstrate a similar pattern of accelerated white matter decline with age and greater white matter deficit in females in OCD and SCZ, with overlap in the spatial pattern of deficits. There was no evidence for statistical differences in overall white matter between OCD and SCZ. Taken together, the results support the notion of shared neurobiology in SCZ and OCD.
authors.affiliation: Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Unit 4-1, Office 125, 1001 Queen Street West, Toronto, ON, M6J 1H4, Canada. colin.hawco@camh.ca.|Temerty Centre for Therapeutic Brain Intervention, Centre for Addiction and Mental Health, Toronto, ON, Canada. colin.hawco@camh.ca.
authors.forename: Colin
authors.identifier: http://orcid.org/0000-0003-3156-4119
authors.initials: C
authors.lastname: Hawco
authors.affiliation: Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Unit 4-1, Office 125, 1001 Queen Street West, Toronto, ON, M6J 1H4, Canada.|Department of Psychiatry, University of Toronto, Toronto, ON, Canada.
authors.forename: Aristotle N
authors.initials: AN
authors.lastname: Voineskos
authors.affiliation: Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Unit 4-1, Office 125, 1001 Queen Street West, Toronto, ON, M6J 1H4, Canada.|Temerty Centre for Therapeutic Brain Intervention, Centre for Addiction and Mental Health, Toronto, ON, Canada.
authors.forename: Natasha
authors.initials: N
authors.lastname: Radhu
authors.affiliation: Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Unit 4-1, Office 125, 1001 Queen Street West, Toronto, ON, M6J 1H4, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Rotenberg
authors.affiliation: Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Unit 4-1, Office 125, 1001 Queen Street West, Toronto, ON, M6J 1H4, Canada.|Department of Psychiatry, University of Toronto, Toronto, ON, Canada.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Ameis
authors.affiliation: Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Unit 4-1, Office 125, 1001 Queen Street West, Toronto, ON, M6J 1H4, Canada.|Temerty Centre for Therapeutic Brain Intervention, Centre for Addiction and Mental Health, Toronto, ON, Canada.
authors.forename: Felicity A
authors.initials: FA
authors.lastname: Backhouse
authors.affiliation: Temerty Centre for Therapeutic Brain Intervention, Centre for Addiction and Mental Health, Toronto, ON, Canada.
authors.forename: Mawahib
authors.initials: M
authors.lastname: Semeralul
authors.affiliation: Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Unit 4-1, Office 125, 1001 Queen Street West, Toronto, ON, M6J 1H4, Canada.|Temerty Centre for Therapeutic Brain Intervention, Centre for Addiction and Mental Health, Toronto, ON, Canada.|Department of Psychiatry, University of Toronto, Toronto, ON, Canada.
authors.forename: Zafiris J
authors.initials: ZJ
authors.lastname: Daskalakis
mesh_terms: D000328:Adult; D000375:Aging / Q000473:pathology*; D001921:Brain / Q000000981:diagnostic imaging* / Q000473:pathology; D038524:Diffusion Magnetic Resonance Imaging; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009771:Obsessive-Compulsive Disorder / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology; D012559:Schizophrenia / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology; D012727:Sex Characteristics; D066127:White Matter / Q000000981:diagnostic imaging* / Q000473:pathology; D055815:Young Adult
keywords: Diffusion tensor imaging; Fractional anisotropy; Obsessive compulsive disorder; Schizophrenia; White matter