Am J Psychiatry 1995; 152:208-212
Copyright © 1995 by American Psychiatric Association
Gender and age at onset in schizophrenia: impact of family history
P Gorwood, M Leboyer, M Jay, C Payan and J Feingold
Laboratoire d'epidemiologie genetique (Institut National de la Sante et de la Recherche Medicale Unite 155), Universite de Paris VII, France.
OBJECTIVE: The 1-year prevalence of schizophrenia was studied in a limited
geographical area of Reunion Island (Indian Ocean) to assess the impact of
family history of schizophrenia on the well-known association between
gender and age at onset. METHOD: The population of schizophrenic patients
meeting the DSM-III-R criteria for schizophrenia (N = 663) was identified
and divided according to the presence of another schizophrenic patient
among the first- and second-degree relatives. RESULTS: As previously
reported, the median age at onset differed between the sexes: the males had
an earlier onset (mean age = 27.8 years) than the females (31.5 years).
Comparison of the ages at onset according to family history revealed that
onset was later for female subjects with a negative family history than for
the three other groups (i.e., males with or without a family history and
females with a family history). No difference emerged in the comparison of
the ages at onset of the males and females with a positive family history.
CONCLUSIONS: Comparison of schizophrenic patients with familial versus
sporadic disorder confirms the absence of a gender effect for age at onset
in the subgroup with familial disorder. This approach also demonstrates the
existence of a subgroup composed of affected females having late onset and
no family history of schizophrenia.
