American Journal of Psychiatry
September 15, 2005

SOCIAL ADVERSITY IN CHILDHOOD RAISES THE RISK OF PSYCHOSIS

OBJECTIVE: There is conflicting evidence concerning the association of
social childhood factors and subsequent psychosis. Previous studies
have had inadequate designs. The aim of the present study was to
describe a broad range of social factors during childhood and the risk
of developing psychosis later in life in a national cohort.

METHOD: The study population consisted of all children born in Sweden
in 1963-1983 -- 2.1 million persons -- in family households
participating in the national census of 1970, 1980, 1985, or 1990.

Hazard ratios were estimated for five different indicators of
socioeconomic position (living in rented apartments, low socioeconomic
status, single-parent households, unemployment, and households
receiving social welfare benefits) from hospital admissions for
schizophrenia and other psychoses during 1987-2002.

RESULTS: Increased age- and sex-adjusted hazard ratios for
schizophrenia and other psychoses were found for all childhood
socioeconomic indicators, ranking from lowest to highest hazard ratio:
rented apartments, low socioeconomic status, single-parent households,
unemployment, and households receiving social welfare benefits. Hazard
ratios increased with an increasing number of adverse social factors
present. Those with four measures of adversity had a 2.7-fold higher
risk of schizophrenia than those with none.

CONCLUSIONS: The results indicate that social adversity in childhood
and fetal life is independently associated with the risk of developing
schizophrenia and other psychoses later in life. The risks increased
with an increasing number of exposures, suggesting a dose-response
relationship.

Citation: S. Wicks,* A. Hjern, D. Gunnell, G. Lewis, C. Dalman,
"Social adversity in childhood and the risk of developing psychosis: a
national cohort study," American Journal of Psychiatry Vol. 162, No. 9
(September 2005) pgs. 1652-7.

* Unit of Epidemiology, Stockholm Centre for Public Health, Norrbacka,
Floor 5, 171 76 Stockholm, Sweden. Email: susanne.wicks@sll.se