CLINICAL HANDBOOK OF SCHIZOPHRENIA

CHAPTER 56GENDERMARY V. SEEMANGender effects are important to schizophrenia. Why is that so? First, they are importantbecause of the many differences between men’s and women’s experience of schizophrenia.Clinicians need to learn to recognize these differences and to assess, treat, and,support men and women with schizophrenia in somewhat different ways to optimize thequality of their lives. Researchers, too, need to study these differences to determinewhether they offer clues to the etiology and pathogenesis of schizophrenia.GENETICSAlthough a positive family history has been claimed in the past to be more common inwomen than in men patients with schizophrenia, there is no good evidence that this is thecase. Genetic risk seems identical in the two sexes, which suggests that the expression ofschizophrenia-prone genes is not affected by biological sex or steroid hormones. That beingsaid, it is possible that in the future some schizophrenia risk genes may still be foundthat are transmitted at higher rates in one sex than in the other. The enzyme catechol-Omethyltransferase(COMT), for instance, has been the object of extensive investigationsas a risk gene because of its major role in dopamine metabolism. In several older studies,a reported gender-specific association of COMT polymorphisms with schizophrenia hadgiven rise to speculations on transmission ratio distortions, but the most recent studieshave found no gender differences.ENVIRONMENTAL RISK FACTORSKnown environmental risk factors for schizophrenia, such as prenatal infection, obstetriccomplications, early rearing environments, and adolescent cannabis use impact the twogenders differently and probably contribute to the reported differences in morbidity risk.The association between prenatal exposure to influenza and later onset of schizophreniais stronger in females, but obstetric complications have been reported to be more stronglyassociated with schizophrenia in men than in women (although this is controversial),575