AUTHOR=Kerins Sarah , Nottage Judith , Salazar de Pablo Gonzalo , Kempton Matthew J. , Tognin Stefania , Niemann Dorien H. , de Haan Lieuwe , van Amelsvoort Thérèse , Kwon Jun Soo , Nelson Barnaby , Mizrahi Romina , McGuire Philip , Fusar-Poli Paolo , The PSYSCAN Consortium , McGuire Philip , Tognin Stefania , Fusar-Poli Paolo , Kempton Matthew , Modinos Gemma , Merritt Kate , Cullen Alexis E. , Mechelli Andrea , Dazzan Paola , Gifford George , Petros Natalia , Antoniades Mathilde , De Micheli Andrea , Vieira Sandra , Spencer Tom , Kahn Rene , Maat Arija , van Hell Erika , Winter Inge , de Haan Lieuwe , Schirmbeck Frederike , Crespo-Facorro Benedicto , Tordesillas-Gutierrez Diana , Setien-Suero Esther , Ayesa-Arriola Rosa , Suarez-Pinilla Paula , Garcia-de la foz Victor Ortiz , Glenthøj Birte , Sørensen Mikkel Erlang , H. Ebdrup Bjørn , Tangmose Karen , Schæbel Helle , Rostrup Egill , Gruber Oliver , Richter Anja , Krämer Bernd , van Amelsvoort Therese , Campforts Bea , Marcelis Machteld , Vingerhoets Claudia , Arango Celso , Díaz-Caneja Covandonga M. , Ayora Miriam , Janssen Joost , Rodríguez-Jiménez Roberto , Díaz-Marsá Marina , Kircher Tilo , Falkenberg Irina , Bitsch Florian , Sommer Jens , Nelson Barnaby , McGorry Patrick , Amminger Paul , McHugh Meredith , Lavoie Suzie , Spark Jessica , Street Rebekah , Galderisi Silvana , Mucci Armida , Bucci Paola , Piegari Giuseppe , Pietrafesa Daria , Giuliani Luigi , Bressan Rodrigo , Zugman André , Gadelha Ary , Rodrigues da Cunha Graccielle , Soo Kwon Jun , Kevin Cho Kang Ik , Young Lee Tae , Kim Minah , Moon Sun-Young , Kyungjin Lho Silvia , Weiser Mark , Mizrahi Romina , Kiang Michael , Gerritsen Cory , Maheandiran Margaret , Ahmed Sarah , Prce Ivana , Lepock Jenny , Sachs Gabriele , Willeit Matthäus , Lenczowski Marzena , Sauerzopf Ullrich , Weidenauer Ana , Furtner-Srajer Julia , Kirschner Matthias , Maatz Anke , Burrer Achim , Stämpfli Philipp , Huber Naemi , Wolfram Kawohl TITLE=Identifying Electroencephalography Biomarkers in Individuals at Clinical High Risk for Psychosis in an International Multi-Site Study JOURNAL=Frontiers in Psychiatry VOLUME=13 YEAR=2022 URL=https://www.frontiersin.org/journals/psychiatry/articles/10.3389/fpsyt.2022.828376 DOI=10.3389/fpsyt.2022.828376 ISSN=1664-0640 ABSTRACT=Background

The clinical high-risk for psychosis (CHR-P) paradigm was introduced to detect individuals at risk of developing psychosis and to establish preventive strategies. While current prediction of outcomes in the CHR-P state is based mostly on the clinical assessment of presenting features, several emerging biomarkers have been investigated in an attempt to stratify CHR-P individuals according to their individual trajectories and refine the diagnostic process. However, heterogeneity across subgroups is a key challenge that has limited the impact of the CHR-P prediction strategies, as the clinical validity of the current research is limited by a lack of external validation across sites and modalities. Despite these challenges, electroencephalography (EEG) biomarkers have been studied in this field and evidence suggests that EEG used in combination with clinical assessments may be a key measure for improving diagnostic and prognostic accuracy in the CHR-P state. The PSYSCAN EEG study is an international, multi-site, multimodal longitudinal project that aims to advance knowledge in this field.

Methods

Participants at 6 international sites take part in an EEG protocol including EEG recording, cognitive and clinical assessments. CHR-P participants will be followed up after 2 years and subcategorised depending on their illness progression regarding transition to psychosis. Differences will be sought between CHR-P individuals and healthy controls and between CHR-P individuals who transition and those who do not transition to psychosis using data driven computational analyses.

Discussion

This protocol addresses the challenges faced by previous studies of this kind to enable valid identification of predictive EEG biomarkers which will be combined with other biomarkers across sites to develop a prognostic tool in CHR-P. The PSYSCAN EEG study aims to pave the way for incorporating EEG biomarkers in the assessment of CHR-P individuals, to refine the diagnostic process and help to stratify CHR-P subjects according to risk of transition. This may improve our understanding of the CHR-P state and therefore aid the development of more personalized treatment strategies.