Neurological soft signs in schizophrenic patients: Influence of age, age at onset, sex, and family history of schizophrenia

Abstract

Neurological soft signs (NSS) are indicators of subtle neurodysfunction which are overrepresented in schizophrenics. The issue of the significance of NSS is still unclear in spite of a considerable amount of literature on the subject. The objective of this study was to investigate the impact on NSS of genetic and environmental factors presumed to be relevant to the etiology and prognosis of schizophrenia. Data on NSS (using a slightly modified version of the Neurological Evaluation Scale) and the age, age at onset, sex and family history of schizophrenia of 50 schizophrenic patients were collected. Extrapyramidal signs were measured with the Extrapyramidal Symptoms Rating Scale. Backward regression analyses with two-factor interactions regression were used to evaluate the influence of the variables on the NSS total score, subscores, and single items. Age at onset and the age-age at onset interaction influenced co-ordination tasks. Sex and the interaction between age and sex influenced sequencing tasks, with males having higher and females lower scores with increasing age. None of the other variables influenced the NSS total score or subscores. Schizophrenics with early onset of disease may perform worse than late-onset patients in motor co-ordination tasks at the onset, but the age-dependent deterioration of motor co-ordination may be more rapid in late-onset patients. Performance in sequencing tasks may be influenced by sex-bound variables.

• Age Age At Onset Neurological Soft Signs Schizophrenia Sex