title: Longitudinal study of symptoms and cognitive function in chronic schizophrenia.
abstract: There is conflicting evidence of a relationship between changes in symptoms and cognitive functioning in schizophrenia. This study investigated longitudinal changes in psychopathology and cognitive functioning in chronic schizophrenia utilising three different dimensional models of symptomatology. Sixty-two patients diagnosed with DSM-IV schizophrenia or schizoaffective disorder were examined on two occasions over a period of 6 months for symptom improvement, measured by Positive and Negative Syndrome Scale (PANSS) [Kay et al., Schizophr. Bull. 13 (1987) 261]. Participants also completed a comprehensive battery of neuropsychological tasks designed to assess attention, verbal and non-verbal memory, psychomotor processing and executive/frontal functioning on both occasions. Twenty-five control subjects were assessed for comparison purposes. Severity of negative symptoms predicted poor neuropsychological performance on IQ, verbal fluency and memory measures at occasion one. However, using regression analyses, significant improvements in symptom ratings over time using two-, three- or five-dimensional models did not predict improvements in any aspect of cognitive functioning measured, except motor speed. The results do not suggest a causal relationship between the course of symptoms and neuropsychological functioning in chronic schizophrenia.
authors.affiliation: Section of Cognitive Psychopharmacology, Division of Psychological Medicine, Institute of Psychiatry, De Crespigny Park, London SE5 8AF, UK.
authors.forename: Catherine
authors.initials: C
authors.lastname: Hughes
authors.forename: Veena
authors.initials: V
authors.lastname: Kumari
authors.forename: William
authors.initials: W
authors.lastname: Soni
authors.forename: Mrigendra
authors.initials: M
authors.lastname: Das
authors.forename: Brendon
authors.initials: B
authors.lastname: Binneman
authors.forename: Sonia
authors.initials: S
authors.lastname: Drozd
authors.forename: Shaun
authors.initials: S
authors.lastname: O'Neil
authors.forename: Vallakalil
authors.initials: V
authors.lastname: Mathew
authors.forename: Tonmoy
authors.initials: T
authors.lastname: Sharma
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D002908:Chronic Disease; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D011596:Psychomotor Disorders / Q000175:diagnosis / Q000209:etiology; D012559:Schizophrenia / Q000150:complications*; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires