Abstract

This study examined the change in cognitive functioning over a more than 45 year period in a group of elderly male schizophrenic patients, controlling for effects of aging, early adult intellectual ability and psychiatric diagnostic status. Subjects were veterans of World War Two. Twenty-two chronic schizophrenic patients were matched with two community-dwelling control groups on age and education level and also compared in terms of intellectual change patterns to a group (Psychiatric) of patients with psychiatric diagnoses of primarily depressive disorder and to a group (Alcoholic) of community-dwelling veterans with a history of heavy drinking. one of the normal control groups (ConTot) was further matched on total wartime score on the Revised Examination "M" Test of intelligence, while the other (ConVoc) was matched on the Vocabulary subtest score. The patterns of change in intellectual abilities were examined within and between groups. Current performance on a battery of neuropsychological tests was also assessed comparatively in relation to the Schizophrenic, Psychiatric and ConVoc groups. Further, the relation of early adult demographic and treatment-related variables to cognitive performance and change was examined. The Schizophrenic group declined in all intellectual abilities, except vocabulary, and showed loss in general intelligence significantly greater than that observed in the ConVoc and ConTot groups. Certain abilities--perceptual-social judgement, mechanical aptitude and arithmetic reasoning--showed greater decline than that associated with normal aging effects. Schizophrenic group stability and the control groups' tendency for increased vocabulary ability argues against its use as a matching criterion in studies lacking premorbid data. While declining more in intellectual ability than the Alcoholic group, the Schizophrenic group did not differ from the Psychiatric group in terms of patterns of cognitive change. The influence of-general rather than specific psychopathology effects is thus suggested. Generally, neuropsychological performance did not differentiate the Schizophrenic group from the Psychiatric and ConVoc groups. Premorbid and treatment-related variables were not predictive of long-term cognitive outcomes in the psychopathology groups. Results were examined in the context of the concept of heterogeneity of course and outcome in schizophrenia.