Risk for schizophrenia--broadening the concepts, pushing back the boundaries.

This paper gives an overview of environmental risk factors for schizophrenia. The presence of certain biological and psychosocial factors at certain points in the lifespan has been linked to later development of schizophrenia. These include prenatal infection, obstetric complications, childhood developmental impairments, early rearing environment, adolescent cannabis use, urban dwelling and membership of a minority population. Some of these risk factors operate on an individual level and some on a societal level but all need to be considered in the context of schizophrenia as a life-long brain disorder. Research interest in schizophrenia, especially neuro-imaging interest, is shifting to ever earlier stages of the disease process and so the journey to discover the causes of schizophrenia is likely to take us right back to the beginning of development.