Antecedents of predominantly negative- and predominantly positive-symptom schizophrenia in a high-risk population

We reanalyzed the Copenhagen schizophrenia high-risk project data set to test recently developed models of the antecedents of predominantly negative and predominantly positive forms of schizophrenia. Among a group of 138 high-risk individuals, those at elevated genetic risk who suffered severe delivery complications and who were autonomic nonresponders during adolescence were significantly more likely than those without this pattern to evidence outcomes of schizophrenia with predominantly negative symptoms (86% vs 0.8%, respectively). Among a group of 160 high-risk subjects, those who escaped delivery complications, who evidenced a high degree of autonomic responsiveness in adolescence, and who experienced severe disruption of the early family rearing environment were significantly more likely than those without this pattern to evidence outcomes of schizophrenia with predominantly positive symptoms (40% vs 1.2%, respectively). In late childhood and early adolescence, predominantly negative-symptom schizophrenics were rated by their teachers as passive, socially isolated, and unresponsive to praise; predominantly positive-symptom schizophrenics were rated as overactive, irritable, distractible, and aggressive. The study is limited by the fact that the hypotheses were based in part on previous analyses of the same data set, by the small number of schizophrenic subjects of each subtype, and by the use of simplified theoretical and statistical models that do not address the multidetermination of negative and positive symptoms.