Objective: Problems in the early mother-infant relation pose a hypothetical risk factor of schizophrenia. We studied the association between very early separation and later development of schizophrenia or other psychoses in a unique data set.
Method: The index cohort consisted of 3020 subjects born in 1945-1965 in Finland who were temporarily isolated from their family immediately after birth to adequate nursing homes due to tuberculosis in the family. The average separation time was 7 months. For every index subject, two reference subjects were matched for sex, year of birth and place of birth. The Finnish Hospital Discharge Register was used to identify subjects with schizophrenia and other psychoses arising from childhood to middle age, between January 1, 1971 and December 31, 1998.
Results: The 28-year cumulative incidence of schizophrenia was 1.6% both in the index cohort and in the reference cohort (rate ratio 1.01, 95% CI 0.75-1.37). The incidences of other psychotic disorders were 1.5% and 1.3% (RR 1.11, 95% CI 0.79-1.58), respectively.
Conclusion: Separation at birth was not found to be associated with either schizophrenia or other psychotic illness. Temporary placement to adequate nursing homes in the first year of life is unlikely to increase the risk for schizophrenia or other psychoses.