Hostname: page-component-cd9895bd7-lnqnp Total loading time: 0 Render date: 2024-12-23T17:24:40.644Z Has data issue: false hasContentIssue false
  • English
  • Français

Testing Ødegaard's selective migration hypothesis: a longitudinal cohort study of risk factors for non-affective psychotic disorders among prospective emigrants

Published online by Cambridge University Press:  01 August 2014

E. van der Ven ,
C. Dalman ,
S. Wicks ,
P. Allebeck ,
C. Magnusson ,
J. van Os  and
J. P. Selten
E. van der Ven*
Affiliation:
Maastricht University, School for Mental Health and Neuroscience, Maastricht, The Netherlands Rivierduinen Psychiatric Institute, Leiden, The Netherlands
C. Dalman
Affiliation:
Public Health Epidemiology, Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden Centre for Epidemiology and Community Medicine, Stockholm County Council, Sweden
S. Wicks
Affiliation:
Public Health Epidemiology, Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden Centre for Epidemiology and Community Medicine, Stockholm County Council, Sweden
P. Allebeck
Affiliation:
Social Medicine, Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden
C. Magnusson
Affiliation:
Public Health Epidemiology, Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden Centre for Epidemiology and Community Medicine, Stockholm County Council, Sweden
J. van Os
Affiliation:
Maastricht University, School for Mental Health and Neuroscience, Maastricht, The Netherlands Department of Psychosis Studies, King's College London, King's Health Partners, Institute of Psychiatry, London, UK
J. P. Selten
Affiliation:
Maastricht University, School for Mental Health and Neuroscience, Maastricht, The Netherlands Rivierduinen Psychiatric Institute, Leiden, The Netherlands
*
*Address for correspondence: E. van der Ven, Rivierduinen Mental Health Institute, GGZ Leiden, Sandifortdreef 19, 2333 ZZ Leiden, The Netherlands. (Email: [email protected])
Get access Rights & Permissions [Opens in a new window]

Abstract

Background

The selection hypothesis posits that the increased rates of psychosis observed among migrants are due to selective migration of people who are predisposed to develop the disorder. To test this hypothesis, we examined whether risk factors for psychosis are more prevalent among future emigrants.

Method

A cohort of 49 321 Swedish military conscripts was assessed at age 18 years on cannabis use, IQ, psychiatric diagnosis, social adjustment, history of trauma and urbanicity of place of upbringing. Through data linkage we examined whether these exposures predicted emigration out of Sweden. We also calculated the emigrants' hypothetical relative risk compared with non-emigrants for developing a non-affective psychotic disorder.

Results

Low IQ [odds ratio (OR) 0.5, 95% confidence interval (95% CI) 0.3–0.9] and ‘poor social adjustment’ (OR 0.4, 95% CI 0.2–0.8) were significantly less prevalent among prospective emigrants, whereas a history of urban upbringing (OR 2.3, 95% CI 1.4–3.7) was significantly more common. Apart from a non-significant increase in cannabis use among emigrants (OR 1.6, 95% CI 0.8–3.1), there were no major group differences in any other risk factors. Compared to non-emigrants, hypothetical relative risks for developing non-affective psychotic disorder were 0.7 (95% CI 0.4–1.2) and 0.8 (95% CI 0.7–1.0), respectively, for emigrants narrowly and broadly defined.

Conclusions

This study adds to an increasing body of evidence opposing the selection hypothesis.

Keywords

Epidemiologymigrationpsychosisrisk factorselection hypothesis
Type
Original Articles
Information
Psychological Medicine , Volume 45 , Issue 4 , March 2015 , pp. 727 - 734
Copyright
Copyright © Cambridge University Press 2014 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Andreasson, S, Allebeck, P, Engstrom, A, Rydberg, U (1987). Cannabis and schizophrenia. A longitudinal study of Swedish conscripts. Lancet 2, 1483–1486.Google Scholar
Bhui, K, Abdi, A, Abdi, M, Pereira, S, Dualeh, M, Robertson, D, Sathyamoorthy, G, Ismail, H (2003). Traumatic events, migration characteristics and psychiatric symptoms among Somali refugees – preliminary communication. Social Psychiatry and Psychiatric Epidemiology 38, 35–43.Google Scholar
Bourque, F, van der Ven, E, Malla, A (2011). A meta-analysis of the risk for psychotic disorders among first- and second-generation immigrants. Psychological Medicine 41, 897–910.Google Scholar
Cannon, TD, Bearden, CE, Hollister, JM, Rosso, IM, Sanchez, LE, Hadley, T (2000). Childhood cognitive functioning in schizophrenia patients and their unaffected siblings: a prospective cohort study. Schizophrenia Bulletin 26, 379–393.Google Scholar
Cantor-Graae, E, Pedersen, CB, McNeil, TF, Mortensen, PB (2003). Migration as a risk factor for schizophrenia: a Danish population-based cohort study. British Journal of Psychiatry 182, 117–122.Google Scholar
Cantor-Graae, E, Selten, JP (2005). Schizophrenia and migration: a meta-analysis and review. American Journal of Psychiatry 162, 12–24.Google Scholar
Dalman, C, Broms, J, Cullberg, J, Allebeck, P (2002). Young cases of schizophrenia identified in a national inpatient register – are the diagnoses valid? Social Psychiatry and Psychiatric Epidemiology 37, 527–531.Google Scholar
David, AS, Malmberg, A, Brandt, L, Allebeck, P, Lewis, G (1997). IQ and risk for schizophrenia: a population-based cohort study. Psychological Medicine 27, 1311–1323.Google Scholar
Ekholm, B, Ekholm, A, Adolfsson, R, Vares, M, Osby, U, Sedvall, GC, Jonsson, EG (2005). Evaluation of diagnostic procedures in Swedish patients with schizophrenia and related psychoses. Nordic Journal of Psychiatry 59, 457–464.Google Scholar
Kristjansson, E, Allebeck, P, Wistedt, B (1987). Validity of the diagnosis schizophrenia in a psychiatric inpatient register: a retrospective application of DSM-III criteria on ICD-8 diagnoses in Stockholm county. Nordic Journal of Psychiatry 41, 229–234.Google Scholar
Lewis, G, David, A, Andreasson, S, Allebeck, P (1992). Schizophrenia and city life. Lancet 340, 137–140.Google Scholar
Lewis, G, David, AS, Malmberg, A, Allebeck, P (2000). Non-psychotic psychiatric disorder and subsequent risk of schizophrenia. Cohort study. British Journal of Psychiatry 177, 416–420.Google Scholar
Lichtenstein, P, Yip, BH, Bjork, C, Pawitan, Y, Cannon, TD, Sullivan, PF, Hultman, CM (2009). Common genetic determinants of schizophrenia and bipolar disorder in Swedish families: a population-based study. Lancet 373, 234–239.Google Scholar
Ludvigsson, JF, Andersson, E, Ekbom, A, Feychting, M, Kim, JL, Reuterwall, C, Heurgren, M, Olausson, PO (2011). External review and validation of the Swedish national inpatient register. BMC Public Health 11, 450.Google Scholar
Lundberg, P, Cantor-Graae, E, Kahima, M, Ostergren, PO (2007). Delusional ideation and manic symptoms in potential future emigrants in Uganda. Psychological Medicine 37, 505–512.Google Scholar
Malmberg, A, Lewis, G, David, A, Allebeck, P (1998). Premorbid adjustment and personality in people with schizophrenia. British Journal of Psychiatry 172, 308–313.Google Scholar
Malzberg, B (1962). Mental disease among Swedish-born and native-born of Swedish parentage in New York State, 1949–1951. Acta Psychiatrica Scandinavica 38, 79–107.Google Scholar
Ødegaard, Ø (1932). Emigration and insanity. Acta Psychiatrica Neurologica Scandinavica (Suppl.) 4, 1–206.Google Scholar
Pedersen, CB, Mortensen, PB, Cantor-Graae, E (2011). Do risk factors for schizophrenia predispose to emigration? Schizophrenia Research 127, 229–234.Google Scholar
Rosenthal, D, Goldberg, I, Jacobsen, B, Wender, PH, Kety, SS, Schulsinger, F, Eldred, CA (1974). Migration, heredity, and schizophrenia. Psychiatry 37, 321–339.Google Scholar
Sellgren, C, Landen, M, Lichtenstein, P, Hultman, CM, Langstrom, N (2011). Validity of bipolar disorder hospital discharge diagnoses: file review and multiple register linkage in Sweden. Acta Psychiatrica Scandinavica 124, 447–453.Google Scholar
Selten, JP, Cantor-Graae, E, Slaets, J, Kahn, RS (2002). Odegaard's selection hypothesis revisited: schizophrenia in Surinamese immigrants to The Netherlands. American Journal of Psychiatry 159, 669–671.Google Scholar
Statistics Sweden (2006). Historic Population Register. Population and Welfare Statistics: Örebro.Google Scholar
Statistics Sweden (2010). Multi-generation Register 2009: a Description of Contents and Quality. Population and Welfare Statistics: Örebro.Google Scholar
van Os, J, Kenis, G, Rutten, BPF (2010). The environment and schizophrenia. Nature 468, 203–212.Google Scholar
WHO (1967). Manual of the International Statistical Classification of Diseases, Injuries and Causes of Death, 1965 Revision. World Health Organization: Geneva.Google Scholar
Zammit, S, Allebeck, P, Andreasson, S, Lundberg, I, Lewis, G (2002). Self reported cannabis use as a risk factor for schizophrenia in Swedish conscripts of 1969: historical cohort study. British Medical Journal 325, 1199.Google Scholar
Zammit, S, Lewis, G, Dalman, C, Allebeck, P (2010). Examining interactions between risk factors for psychosis. British Journal of Psychiatry 197, 207–211.Google Scholar