Longitudinal study of cognitive function in first-episode and recent-onsetschizophrenia

Objective: Whether cognitive function in schizophrenia deteriorates, improv es, or remains stable is a crucial question, Few studies have examined the longitudinal stability of cognitive function and the relationship between c ognitive performance and clinical symptoms over time in a cohort of well-tr eated patients with schizophrenia. Method: In the present study, 54 patient s with first-episode and recent-onset schizophrenia completed a comprehensi ve cognitive test battery and were rated on symptom measures at index hospi talization and again after 5 years. Results: Performance IQ and full-scale IQ significantly improved, whereas verbal IQ did not change. Group performa nce improved on some of the neuropsychological tests, including the Circle A letter-cancellation task, free recall of logical memory test score, and t he Wisconsin Card Sorting Test, Mean finger-tapping performance worsened ov er time, whereas performance on other neuropsychological tests did not chan ge. Negative, psychotic, and disorganized symptoms significantly improved o ver the time period. Changes in negative symptoms were correlated with perf ormance changes in verbal IQ and full-scale IQ but not performance IQ. Impr ovement in verbal cognition was observed when negative symptoms improved. P sychotic and disorganized symptom dimensions were not correlated with any I Q measure, Conclusions: These results indicate that in a cohort of young pa tients receiving neuroleptic treatment early in their illness, cognitive pe rformance does not deteriorate-and may improve. Only one of the three sympt om dimensions-negative-was associated with change in cognitive performance. This study supports the view that negative symptoms are associated with a poor long-term cognitive outcome and may be closely related to the primary cognitive deficit in schizophrenia.