Sleep Med Psychophysiol.  2004 Jun;11(1):44-49.

Symptoms and Cognitive Function in Chronic Schizophrenia: 6 Months Follow-up Study

• Kim CK
• Kim SH
• Choe BM

Abstract

OBJECTIVES
The purpose of this study was to investigate whether longitudinal changes in positive and negative symptoms affect cognitive functioning in chronic schizophrenia. METHODS: Sixty-eight patients diagnosed with DSM-IV schizophrenia were examined on two occasions over 6 months for symptoms and cognitive changes. Symptoms were measured by PANSS. Cognitive functions were examined for sustained attention, executive function, concentration and attention, and verbal memory and learning using Degraded Stimulus Continuous Performance Test, Wisconsin Card Sorting Test, Digit Span, and Rey Auditory Verbal Learning Test, respectively. Twenty control subjects were assessed to compare the cognitive scores of remitted schizophrenic patients. RESULTS: Patients showed significant improvement in symptoms and all cognitive tests after 6 months treatments. Significant improvements in positive and negative symptoms did not predict improvements in any aspect of cognitive functioning measured. Normal controls performed significantly better than remitted schizophrenic patients on all cognitive tests. The results show no relationship between change in symptoms and change in cognition in chronic schizophrenia. CONCLUSION: We suggest that symptomatic and cognitive impairment may be a distinct construct. These findings highlight the importance of treating cognitive impairment in addition to the clinical symptoms of schizophrenia.

Keyword

Cognitive function; Symptoms; Schizophrenia

MeSH Terms

Cognition
Diagnostic and Statistical Manual of Mental Disorders
Executive Function
Follow-Up Studies*
Humans
Learning
Memory
Schizophrenia*
Verbal Learning
Wisconsin