Early diagnosis of schizophrenia - the first step towards secondary prevention

Objective: To review current knowledge of risk factors associated with schizophrenia and the development of diagnostic markers aimed at the delay or attenuation of the first psychotic episode. Method: Studies relating to the development of disease and the risk factors that could inform predictive markers are reviewed, including high-risk studies, birth-cohort studies, and retrospective and follow-back studies. Results: Future schizophrenic patients present with delayed developmental milestones, speech and behavioural difficulties, and lower IQ scores than non-cases. Conclusion: Results are consistent with the notion that schizophrenia is a developmental disease and that such antecedents are present; further research is required to improve the specificity of diagnostic markers and predictive power before these can be used to prevent or delay psychotic episodes of schizophrenia.