Familial and sporadic schizophrenia: a comparison of somatic diseases and abuse in patients and their relatives.
OBJECTIVE
Comparing schizophrenia patients on the basis of familial and non-familial forms of the illness provides a promising approach to the identification of genes involved in schizophrenia. The aim of this study was to search for somatic factors that discriminate between patients with and without a family history of schizophrenia and between their relatives.


METHODS
Ninety-five schizophrenia patients were structurally interviewed about mental and physical health and alcohol and substance use in themselves and their families. Besides this, complementary information was obtained from the patients' case records. Patients with (41%) and without (59%) a family history were then compared.


RESULTS
The main differences were found in the patients' relatives. Fewer patients with a family history, compared with patients without a family history, had relatives with cancer (p = 0.002). Conversely, there was a tendency towards that more patients with a family history, compared with patients without a family history, had relatives with cardiac infarction (p = 0.05).


CONCLUSIONS
The genetic risk associated with schizophrenia seems to cosegregate into a factor(s) that protects against cancer and possibly also increases the risk for cardiac infarction.
1Department of Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden.
Kristina
K
Melkersson