What we learn about bipolar disorder from large‐scale neuroimaging: Findings and future directions from the <scp>ENIGMA</scp> Bipolar Disorder Working Group
Christopher R. K. Ching, Derrek P. Hibar, Tiril P. Gurholt, Abraham Nunes, Sophia I. Thomopoulos, Christoph Abé, Ingrid Agartz, Rachel M. Brouwer, Dara M. Cannon, Sonja M. C. de Zwarte, Lisa T. Eyler, Pauline Favre, Tomáš Hájek, Unn K. Haukvik, Josselin Houenou, Mikael Landén, Tristram A. Lett, Colm McDonald, Leila Nabulsi, Yash Patel, Melissa Pauling, Tomáš Paus, Joaquim Raduà, Márcio Gerhardt Soeiro‐de‐Souza, Giulia Tronchin, Neeltje E.M. van Haren, Eduard Vieta, Henrik Walter, Ling‐Li Zeng, Martin Alda, Jorge Almeida, Dag Alnæs, Sílvia Alonso-Lana, Cara M. Altimus, Michael Bauer, Bernhard T. Baune, Carrie E. Bearden, Marcella Bellani, Francesco Benedetti, Michael Berk, Amy C. Bilderbeck, Hilary P. Blumberg, Erlend Bøen, Irene Bollettini, Caterina del Mar Bonnín, Paolo Brambilla, Erick J. Canales‐Rodríguez, Xavier Caseras, Orwa Dandash, Udo Dannlowski, Giuseppe Delvecchio, Ana M. Díaz‐Zuluaga, Danai Dima, Édouard Duchesnay, Torbjørn Elvsåshagen, Scott C. Fears, Sophia Frangou, Janice M. Fullerton, David C. Glahn, José Manuel Goikolea, Melissa J. Green, Dominik Grotegerd, Oliver Gruber, Bartholomeus C. M. Haarman, Chantal Henry, Fleur M. Howells, Victoria Ives‐Deliperi, Andreas Jansen, Tilo Kircher, Christian Knöchel, Bernd Krämer, Beny Lafer, Carlos López‐Jaramillo, Rodrigo Machado‐Vieira, Bradley J. MacIntosh, Elisa Melloni, Philip B. Mitchell, Igor Nenadić, Fabiano G. Nery, Allison C. Nugent, Viola Oertel, Roel A. Ophoff, Miho Ota, Bronwyn J. Overs, Dániel Pham, Mary L. Phillips, Julian A. Pineda‐Zapata, Sara Poletti, Mircea Polosan, Edith Pomarol‐Clotet, Arnaud Pouchon, Yann Quidé, Maria M. Rive, Gloria Roberts, Henricus G. Ruhé, Raymond Salvador, Salvador Sarró, Theodore D. Satterthwaite, Aart H. Schene, Kang Sim
Abstract
MRI-derived brain measures offer a link between genes, the environment and behavior and have been widely studied in bipolar disorder (BD). However, many neuroimaging studies of BD have been underpowered, leading to varied results and uncertainty regarding effects. The Enhancing Neuro Imaging Genetics through Meta-Analysis (ENIGMA) Bipolar Disorder Working Group was formed in 2012 to empower discoveries, generate consensus findings and inform future hypothesis-driven studies of BD. Through this effort, over 150 researchers from 20 countries and 55 institutions pool data and resources to produce the largest neuroimaging studies of BD ever conducted. The ENIGMA Bipolar Disorder Working Group applies standardized processing and analysis techniques to empower large-scale meta- and mega-analyses of multimodal brain MRI and improve the replicability of studies relating brain variation to clinical and genetic data. Initial BD Working Group studies reveal widespread patterns of lower cortical thickness, subcortical volume and disrupted white matter integrity associated with BD. Findings also include mapping brain alterations of common medications like lithium, symptom patterns and clinical risk profiles and have provided further insights into the pathophysiological mechanisms of BD. Here we discuss key findings from the BD working group, its ongoing projects and future directions for large-scale, collaborative studies of mental illness.