TY - JOUR
T1 - Risk factors and peripheral biomarkers for schizophrenia spectrum disorders
T2 - an umbrella review of meta-analyses
AU - Belbasis, L.
AU - Köhler, C. A.
AU - Stefanis, N.
AU - Stubbs, B.
AU - van Os, J.
AU - Vieta, E.
AU - Seeman, M. V.
AU - Arango, C.
AU - Carvalho, A. F.
AU - Evangelou, E.
N1 - Funding Information:
1Department of Hygiene and Epidemiology, University of Ioannina Medical School, Ioannina, Greece, 2Translational Psychiatry Research Group, Department of Clinical Medicine, Federal University of CearáMedical School, Fortaleza, Brazil, 3Department of Psychiatry, Eginition Hospital, National and Kapodistrian University of Athens Medical School, Athens, Greece, 4Department of Physiotherapy, South London and Maudsley NHS Foundation Trust, London, UK, 5Department of Health Service and Population Research, Institute of Psychiatry, King’s College London, London, UK, 6Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Centre Utrecht, Utrecht, The Netherlands, 7Department of Psychosis Studies, Institute of Psychiatry, King’s College London, London, UK, 8Bipolar Disorder Unit, Institute of Neuroscience, University of Barcelona, IDIBAPS and CIBERSAM, Barcelona, Spain, 9Institute of Medical Science, University of Toronto, Toronto, ON, Canada, 10Department of Child and Adolescent Psychiatry, University Hospital Gregorio Marañón, Complutense University of Madrid Medical School, CIBERSAM, Madrid, Spain, 11Department of Psychiatry, University of Toronto, Toronto, ON, Canada, 12Centre for Addiction & Mental Health (CAMH), Toronto, ON, Canada and 13Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK Key words: epidemiology; meta-analysis; psychosis; risk factors; schizophrenia Evangelos Evangelou, Department of Hygiene and Epidemiology, University of Ioannina Medical School, Ioannina, Greece. E-mail: [email protected]
Publisher Copyright:
© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
PY - 2018/2/1
Y1 - 2018/2/1
N2 - Objective: This study aimed to systematically appraise the meta-analyses of observational studies on risk factors and peripheral biomarkers for schizophrenia spectrum disorders. Methods: We conducted an umbrella review to capture all meta-analyses and Mendelian randomization studies that examined associations between non-genetic risk factors and schizophrenia spectrum disorders. For each eligible meta-analysis, we estimated the summary effect size estimate, its 95% confidence and prediction intervals and the I2 metric. Additionally, evidence for small-study effects and excess significance bias was assessed. Results: Overall, we found 41 eligible papers including 98 associations. Sixty-two associations had a nominally significant (P-value <0.05) effect. Seventy-two of the associations exhibited large or very large between-study heterogeneity, while 13 associations had evidence for small-study effects. Excess significance bias was found in 18 associations. Only five factors (childhood adversities, cannabis use, history of obstetric complications, stressful events during adulthood, and serum folate level) showed robust evidence. Conclusion: Despite identifying 98 associations, there is only robust evidence to suggest that cannabis use, exposure to stressful events during childhood and adulthood, history of obstetric complications, and low serum folate level confer a higher risk for developing schizophrenia spectrum disorders. The evidence on peripheral biomarkers for schizophrenia spectrum disorders remains limited.
AB - Objective: This study aimed to systematically appraise the meta-analyses of observational studies on risk factors and peripheral biomarkers for schizophrenia spectrum disorders. Methods: We conducted an umbrella review to capture all meta-analyses and Mendelian randomization studies that examined associations between non-genetic risk factors and schizophrenia spectrum disorders. For each eligible meta-analysis, we estimated the summary effect size estimate, its 95% confidence and prediction intervals and the I2 metric. Additionally, evidence for small-study effects and excess significance bias was assessed. Results: Overall, we found 41 eligible papers including 98 associations. Sixty-two associations had a nominally significant (P-value <0.05) effect. Seventy-two of the associations exhibited large or very large between-study heterogeneity, while 13 associations had evidence for small-study effects. Excess significance bias was found in 18 associations. Only five factors (childhood adversities, cannabis use, history of obstetric complications, stressful events during adulthood, and serum folate level) showed robust evidence. Conclusion: Despite identifying 98 associations, there is only robust evidence to suggest that cannabis use, exposure to stressful events during childhood and adulthood, history of obstetric complications, and low serum folate level confer a higher risk for developing schizophrenia spectrum disorders. The evidence on peripheral biomarkers for schizophrenia spectrum disorders remains limited.
KW - epidemiology
KW - meta-analysis
KW - psychosis
KW - risk factors
KW - schizophrenia
UR - http://www.scopus.com/inward/record.url?scp=85039741412&partnerID=8YFLogxK
U2 - 10.1111/acps.12847
DO - 10.1111/acps.12847
M3 - Article
AN - SCOPUS:85039741412
SN - 0001-690X
VL - 137
SP - 88
EP - 97
JO - Acta Psychiatrica Scandinavica
JF - Acta Psychiatrica Scandinavica
IS - 2
ER -