Prevention and early intervention in schizophrenia: facts and visions.

There are large-scale preventive programmes to reduce the risk of death and disability caused by several frequent physical diseases. The primary and secondary prevention of schizophrenia, a disorder entailing many years of life in disability, is still being neglected. Prevention is aimed at reducing the incidence, severity or consequences of the disorder. To find ways of preventive intervention in schizophrenia, the aetiological risk factors must be identified, then eliminated or modified. As possible targets pre-, peri- and postnatal complications, urbanicity and early behavioural risk indicators are discussed. As examples of successful early prevention targeted at risk indicators attempts to prevent depression and violence are considered. The most promising approach at present is secondary prevention focused on early illness course. Based on a controlled retrospective assessment of 232 first illness episodes the course of prodromi, impairments and psychotic symptoms prior to the climax of the first episode is shown. Most of the social consequences occur before the first treatment contact, thus making plain the urgent need for preventive action. Tools sufficiently validated are not yet available for early diagnosis and prediction of psychosis onset at the prepsychotic stage. So intervention has to be based on high-risk inclusion criteria, which exclude large proportions of at-risk persons. Appropriate early intervention at the prepsychotic, prodromal and the early psychotic stage as well as relevant ethical considerations are discussed. The frequency of and distress associated with single psychotic symptoms in the general population are potent predictors of a psychosis. The vision of treating this early illness dimension with third-generation, side-effect-free antipsychotics or of preventing its onset by oestrogen-like substances is discussed.