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Influence of birth cohort on age of onset cluster analysis in bipolar I disorder

Published online by Cambridge University Press:  15 April 2020

M. Bauer*
Affiliation:
Department of Psychiatry and Psychotherapy, Universitätsklinikum Carl Gustav Carus, Technische Universität Dresden, Germany Fetscherstr, 74, 01307Dresden, Germany
T. Glenn
Affiliation:
ChronoRecord Association, Fullerton, CA, USA
M. Alda
Affiliation:
Department of Psychiatry, Dalhousie University, Halifax, NS, Canada
O.A. Andreassen
Affiliation:
NORMENT - K.G. Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital & Institute of Clinical Medicine, Oslo, Norway
E. Angelopoulos
Affiliation:
Department of Psychiatry, University of Athens Medical School, Eginition Hospital, Athens, Greece
R. Ardau
Affiliation:
Unit of Clinical Pharmacology, University Hospital of Cagliari, Cagliari, Italy
C. Baethge
Affiliation:
Department of Psychiatry and Psychotherapy, University of Cologne Medical School, Cologne, Germany
R. Bauer
Affiliation:
Department of Psychiatry and Psychotherapy, Universitätsklinikum Carl Gustav Carus, Technische Universität Dresden, Germany Fetscherstr, 74, 01307Dresden, Germany
F. Bellivier
Affiliation:
Psychiatrie, GH Saint-Louis – Lariboisière – F.-Widal, AP–HP, INSERM UMR-S1144, Faculté de Médecine, Université D.-Diderot, Paris, France FondaMental Fondation, Créteil, France
R.H. Belmaker
Affiliation:
Department of Psychiatry, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva Mental Health Center, Beer Sheva, Israel
M. Berk
Affiliation:
IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Victoria3220, Australia Department of Psychiatry, ORYGEN Youth Health Research Centre, Centre for Youth Mental Health and the Florey Institute for Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria3052, Australia
T.D. Bjella
Affiliation:
NORMENT - K.G. Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital & Institute of Clinical Medicine, Oslo, Norway
L. Bossini
Affiliation:
Department of Molecular Medicine and Department of Mental Health (DAI), University of Siena and University of Siena Medical Center (AOUS), Siena, Italy
Y. Bersudsky
Affiliation:
Department of Psychiatry, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva Mental Health Center, Beer Sheva, Israel
E.Y.W. Cheung
Affiliation:
Department of General Adult Psychiatry, Castle Peak Hospital, Hong Kong
J. Conell
Affiliation:
Department of Psychiatry and Psychotherapy, Universitätsklinikum Carl Gustav Carus, Technische Universität Dresden, Germany Fetscherstr, 74, 01307Dresden, Germany
M. Del Zompo
Affiliation:
Section of Neurosciences and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, Sardinia, Italy
S. Dodd
Affiliation:
IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Victoria3220, Australia Department of Psychiatry, University of Melbourne, Parkville, Victoria3052, Australia
B. Etain
Affiliation:
AP–HP, Hôpitaux Universitaires Henri-Mondor, INSERM U955 (IMRB), Université Paris Est, and FondaMental Fondation, Créteil, France
A. Fagiolini
Affiliation:
Department of Molecular Medicine and Department of Mental Health (DAI), University of Siena and University of Siena Medical Center (AOUS), Siena, Italy
M.A. Frye
Affiliation:
Department of Psychiatry & Psychology, Mayo Clinic Depression Center, Mayo Clinic, Rochester, MN, USA
K.N. Fountoulakis
Affiliation:
3rd Department of Psychiatry, Division of Neurosciences, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
J. Garneau-Fournier
Affiliation:
Department of Psychiatry and Behavioral Sciences, Stanford School of Medicine, Palo Alto, CA, USA
A. Gonzalez-Pinto
Affiliation:
Department of Psychiatry, University Hospital of Alava, University of the Basque Country, CIBERSAM, Vitoria, Spain
H. Harima
Affiliation:
Department of Psychiatry, Tokyo Metropolitan Matsuzawa Hospital, Setagaya, Tokyo, Japan
S. Hassel
Affiliation:
Department of Psychiatry, Faculty of Medicine, University of Calgary, Calgary, AB, Canada
C. Henry
Affiliation:
AP–HP, Hôpitaux Universitaires Henri-Mondor, INSERM U955 (IMRB), Université Paris Est, and FondaMental Fondation, Créteil, France
A. Iacovides
Affiliation:
3rd Department of Psychiatry, Division of Neurosciences, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
E.T. Isometsä
Affiliation:
Department of Psychiatry, Institute of Clinical Medicine, University of Helsinki, Helsinki, Finland National Institute for Health and Welfare, Helsinki, Finland
F. Kapczinski
Affiliation:
Laboratory of Molecular Psychiatry, Hospital de Clínicas de Porto Alegre, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
S. Kliwicki
Affiliation:
Department of Adult Psychiatry, Poznan University of Medical Sciences, Poznan, Poland
B. König
Affiliation:
BIPOLAR Zentrum Wiener Neustadt, Wiener Neustadt, Austria
R. Krogh
Affiliation:
Department of Affective Disorders, Q, Mood Disorders Research Unit, Aarhus University Hospital, Aarhus, Denmark
M. Kunz
Affiliation:
Laboratory of Molecular Psychiatry, Hospital de Clínicas de Porto Alegre, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
B. Lafer
Affiliation:
Bipolar Disorder Research Program, Department of Psychiatry, University of São Paulo Medical School, São Paulo, Brazil
E.R. Larsen
Affiliation:
Department of Affective Disorders, Q, Mood Disorders Research Unit, Aarhus University Hospital, Aarhus, Denmark
U. Lewitzka
Affiliation:
Department of Psychiatry and Psychotherapy, Universitätsklinikum Carl Gustav Carus, Technische Universität Dresden, Germany Fetscherstr, 74, 01307Dresden, Germany
C. Lopez-Jaramillo
Affiliation:
Mood Disorders Program, Fundacion San Vicente de Paul, Department of Psychiatry, Universidad de Antioquia, Medellín, Colombia
G. MacQueen
Affiliation:
Department of Psychiatry, Faculty of Medicine, University of Calgary, Calgary, AB, Canada
M. Manchia
Affiliation:
Department of Psychiatry, Dalhousie University, Halifax, NS, Canada
W. Marsh
Affiliation:
Department of Psychiatry, University of Massachusetts, Worcester, MA, USA
M. Martinez-Cengotitabengoa
Affiliation:
Department of Psychiatry, University Hospital of Alava, University of the Basque Country, CIBERSAM, Vitoria, Spain
I. Melle
Affiliation:
NORMENT - K.G. Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital & Institute of Clinical Medicine, Oslo, Norway
S. Monteith
Affiliation:
Michigan State University College of Human Medicine, Traverse City Campus, Traverse City, MI, USA
G. Morken
Affiliation:
Department of Neuroscience, NTNU, and St Olavs’ University Hospital, Trondheim, Norway
R. Munoz
Affiliation:
Department of Psychiatry, University of California San Diego, San Diego, CA, USA
F.G. Nery
Affiliation:
Bipolar Disorder Research Program, Department of Psychiatry, University of São Paulo Medical School, São Paulo, Brazil
C. O’Donovan
Affiliation:
Department of Psychiatry, Dalhousie University, Halifax, NS, Canada
Y. Osher
Affiliation:
Department of Psychiatry, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva Mental Health Center, Beer Sheva, Israel
A. Pfennig
Affiliation:
Department of Psychiatry and Psychotherapy, Universitätsklinikum Carl Gustav Carus, Technische Universität Dresden, Germany Fetscherstr, 74, 01307Dresden, Germany
D. Quiroz
Affiliation:
Deparment of Psychiatry, Diego Portales University, Santiago, Chile
R. Ramesar
Affiliation:
UCT/MRC Human Genetics Research Unit, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
N. Rasgon
Affiliation:
Department of Psychiatry and Behavioral Sciences, Stanford School of Medicine, Palo Alto, CA, USA
A. Reif
Affiliation:
Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital Frankfurt, Goethe-University Frankfurt am Main, Germany
P. Ritter
Affiliation:
Department of Psychiatry and Psychotherapy, Universitätsklinikum Carl Gustav Carus, Technische Universität Dresden, Germany Fetscherstr, 74, 01307Dresden, Germany
J.K. Rybakowski
Affiliation:
Department of Adult Psychiatry, Poznan University of Medical Sciences, Poznan, Poland
K. Sagduyu
Affiliation:
Department of Psychiatry, University of Missouri Kansas City School of Medicine, Kansas City, MO, USA
A.M. Scippa
Affiliation:
Department of Neuroscience and Mental Health, Federal University of Bahia, Salvador, Brazil
E. Severus
Affiliation:
Department of Psychiatry and Psychotherapy, Universitätsklinikum Carl Gustav Carus, Technische Universität Dresden, Germany Fetscherstr, 74, 01307Dresden, Germany
C. Simhandl
Affiliation:
BIPOLAR Zentrum Wiener Neustadt, Wiener Neustadt, Austria
D.J. Stein
Affiliation:
Department of Psychiatry, University of Cape Town, Cape Town, South Africa
S. Strejilevich
Affiliation:
Bipolar Disorder Program, Neuroscience Institute, Favaloro University, Buenos Aires, Argentina
A. Hatim Sulaiman
Affiliation:
Department of Psychological Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
K. Suominen
Affiliation:
City of Helsinki, Department of Social Services and Health Care, Psychiatry, Helsinki, Finland
H. Tagata
Affiliation:
Department of Psychiatry, Tokyo Metropolitan Matsuzawa Hospital, Setagaya, Tokyo, Japan
Y. Tatebayashi
Affiliation:
Schizophrenia & Affective Disorders Research Project, Tokyo Metropolitan Institute of Medical Science, Seatagaya, Tokyo, Japan
C. Torrent
Affiliation:
Clinical Institute of Neuroscience, Hospital Clinic, University of Barcelona, IDIBAPS, CIBERSAM, Barcelona, Catalonia, Spain
E. Vieta
Affiliation:
Clinical Institute of Neuroscience, Hospital Clinic, University of Barcelona, IDIBAPS, CIBERSAM, Barcelona, Catalonia, Spain
B. Viswanath
Affiliation:
Department of Psychiatry, NIMHANS, Bangalore560029, India
M.J. Wanchoo
Affiliation:
Department of Psychiatry & Psychology, Mayo Clinic Depression Center, Mayo Clinic, Rochester, MN, USA
M. Zetin
Affiliation:
Department of Psychology, Chapman University, Orange, CA, USA
P.C. Whybrow
Affiliation:
Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior University of California Los Angeles (UCLA), Los Angeles, CA, USA
*
* Corresponding author. Tel.: +49 351 458 0; fax: +49 30 450 51 79 62. E-mail address:michael.bauer@uniklinikum-dresden.de (M. Bauer).
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Abstract

Purpose:

Two common approaches to identify subgroups of patients with bipolar disorder are clustering methodology (mixture analysis) based on the age of onset, and a birth cohort analysis. This study investigates if a birth cohort effect will influence the results of clustering on the age of onset, using a large, international database.

Methods:

The database includes 4037 patients with a diagnosis of bipolar I disorder, previously collected at 36 collection sites in 23 countries. Generalized estimating equations (GEE) were used to adjust the data for country median age, and in some models, birth cohort. Model-based clustering (mixture analysis) was then performed on the age of onset data using the residuals. Clinical variables in subgroups were compared.

Results:

There was a strong birth cohort effect. Without adjusting for the birth cohort, three subgroups were found by clustering. After adjusting for the birth cohort or when considering only those born after 1959, two subgroups were found. With results of either two or three subgroups, the youngest subgroup was more likely to have a family history of mood disorders and a first episode with depressed polarity. However, without adjusting for birth cohort (three subgroups), family history and polarity of the first episode could not be distinguished between the middle and oldest subgroups.

Conclusion:

These results using international data confirm prior findings using single country data, that there are subgroups of bipolar I disorder based on the age of onset, and that there is a birth cohort effect. Including the birth cohort adjustment altered the number and characteristics of subgroups detected when clustering by age of onset. Further investigation is needed to determine if combining both approaches will identify subgroups that are more useful for research.

Type
Original article
Copyright
Copyright © European Psychiatric Association 2020

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