Cortical thickness and surface area as an endophenotype in bipolar disorder type I patients and their first-degree relatives

Nefize Yalin; Aybala Saricicek; Ceren Hidiroglu; Andre Zugman; Nese Direk; Emel Ada; Berrin Cavusoglu; Ayşe Er; Gizem Isik; Deniz Ceylan; Zeliha Tunca; Matthew J Kempton; Aysegul Ozerdem

doi:10.1016/j.nicl.2019.101695

Cortical thickness and surface area as an endophenotype in bipolar disorder type I patients and their first-degree relatives

Neuroimage Clin. 2019:22:101695. doi: 10.1016/j.nicl.2019.101695. Epub 2019 Jan 29.

Authors

Nefize Yalin¹, Aybala Saricicek², Ceren Hidiroglu³, Andre Zugman⁴, Nese Direk⁵, Emel Ada⁶, Berrin Cavusoglu⁷, Ayşe Er⁷, Gizem Isik⁷, Deniz Ceylan⁷, Zeliha Tunca⁵, Matthew J Kempton⁸, Aysegul Ozerdem⁹

Affiliations

¹ Centre for Affective Disorders, Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK; Department of Neuroscience, Institute of Health Sciences, Dokuz Eylul University, Izmir, Turkey. Electronic address: nefize.yalin@kcl.ac.uk.
² Department of Neuroscience, Institute of Health Sciences, Dokuz Eylul University, Izmir, Turkey; Department of Psychiatry, Faculty of Medicine, Katip Celebi University, Izmir, Turkey.
³ Department of Psychology, Faculty of Arts, Dokuz Eylul University, Izmir, Turkey.
⁴ Interdisciplinary Laboratory of Clinical Neuroscience (LINC), Department of Psychiatry, Universidade Federal de Sao Paulo, Sao Paulo, Brazil.
⁵ Department of Psychiatry, Faculty of Medicine, Dokuz Eylul University, Izmir, Turkey.
⁶ Department of Radiology, Faculty of Medicine, Dokuz Eylul University, Izmir, Turkey.
⁷ Department of Neuroscience, Institute of Health Sciences, Dokuz Eylul University, Izmir, Turkey.
⁸ Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK; Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.
⁹ Department of Neuroscience, Institute of Health Sciences, Dokuz Eylul University, Izmir, Turkey; Department of Psychiatry, Faculty of Medicine, Dokuz Eylul University, Izmir, Turkey.

Abstract

Objectives: So far, few studies have investigated cortical thickness (CT) and surface area (SA) measures in bipolar disorder type I (BDI) in comparison to a high genetic risk group such as first-degree relatives (FR). This study aimed to examine CT and SA differences between BDI, FR and healthy controls (HC).

Methods: 3D T1 magnetic resonance images were acquired from 27 euthymic BDI patients, 24 unaffected FR and 29 HC. CT and SA measures were obtained with FreeSurfer version 5.3.0. Generalized estimating equations were used to compare CT and SA between groups. Group comparisons were repeated with restricting the FR group to 17 siblings (FR-SB) only.

Results: \Mean age in years was 36.3 ± 9.5 for BDI, 32.1 ± 10.9 for FR, 34.7 ± 9.8 for FR-SB and 33.1 ± 9.0 for HC group respectively. BDI patients revealed larger SA of left pars triangularis (LPT) compared to HC (p = .001). In addition, increased SA in superior temporal cortex (STC) in FR-SB group compared to HC was identified (p = .0001).

Conclusions: Our result of increased SA in LPT of BDI could be a disease marker and increased SA in STC of FR-SB could be a marker related with resilience to illness.

Keywords: Bipolar disorder type I; Cortical thickness; Endophenotype; First-degree relative; Surface area.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Biomarkers
Bipolar Disorder / diagnostic imaging
Bipolar Disorder / pathology*
Cerebral Cortex / diagnostic imaging
Cerebral Cortex / pathology*
Endophenotypes*
Female
Humans
Magnetic Resonance Imaging
Male
Middle Aged
Neuroimaging / methods*
Siblings
Young Adult

Substances

Biomarkers