Schizophrenia with onset after age 50 years I: Phenomenology and risk factors

Background Schizophrenia occurring for the first time in late life may be a distinct entity or part of a continuum. Aims Can late-onset schizophrenia (LOS) and early-onset schizophrenia (EOS) be differentiated by their phenomenology and risk factors to their develop ment! Method Convenience samples of 27 DSM-III-R defined LOS subjects, 30 EOS sub jects and 34 control subjects were systematically assessed. Results Premorbidly, both groups of subjects with schizophrenia had persona lity traits that were different from controls but not from each other. The EOS subjects had more family members with a history of psychiatric illness or schizophrenia and less hearing impairment than the other two groups, whi ch did not differ from each other. Clinically, LOS and EOS subjects were si milar, except that EOS subjects had more negative symptom scores, tended to have more delusions of guilt/sin and of being controlled and more formal t hought disorder, and had significantly poorer instrumental activities of da ily living. Conclusions Phenomenology and risk factors do not distinguish discrete LOS. Declaration of interest The study was supported by the National Health and Medical Research Council of Australia and the Rebecca Cooper Foundation.