BACKGROUND: Studies of chronic schizophrenia suggest that there are subgroups with different profiles of cognitive impairment. AIMS: To determine whether such heterogeneity is present at illness onset and any relationship to clinical variables. METHOD: Ninety-three community patients with first-episode schizophrenia and 50 healthy volunteers were assessed for premorbid (Revised National Adult Reading Test) and current IQ, memory and executive function. RESULTS: Half of those with schizophrenia had preserved IQ in the normal range but there was evidence of a specific impairment in spatial working memory even in those with high/average IQ; 37 out of 93 (40%) had generalised cognitive decline. Those with low premorbid IQ were significantly younger at illness onset. For the entire group, age at onset correlated positively with premorbid but not current IQ. CONCLUSIONS: At illness onset, cognitive heterogeneity is present in people with schizophrenia, with a high proportion having undergone general cognitive decline. However, working memory impairment may be a common feature. Lower premorbid IQ is a risk factor for an earlier onset.
BACKGROUND: Studies of chronic schizophrenia suggest that there are subgroups with different profiles of cognitive impairment. AIMS: To determine whether such heterogeneity is present at illness onset and any relationship to clinical variables. METHOD: Ninety-three community patients with first-episode schizophrenia and 50 healthy volunteers were assessed for premorbid (Revised National Adult Reading Test) and current IQ, memory and executive function. RESULTS: Half of those with schizophrenia had preserved IQ in the normal range but there was evidence of a specific impairment in spatial working memory even in those with high/average IQ; 37 out of 93 (40%) had generalised cognitive decline. Those with low premorbid IQ were significantly younger at illness onset. For the entire group, age at onset correlated positively with premorbid but not current IQ. CONCLUSIONS: At illness onset, cognitive heterogeneity is present in people with schizophrenia, with a high proportion having undergone general cognitive decline. However, working memory impairment may be a common feature. Lower premorbid IQ is a risk factor for an earlier onset.
Authors: Alan E Ceaser; Terry E Goldberg; Michael F Egan; Robert P McMahon; Daniel R Weinberger; James M Gold Journal: Biol Psychiatry Date: 2008-07-02 Impact factor: 13.382
Authors: M Hvoslef-Eide; A C Mar; S R O Nilsson; J Alsiö; C J Heath; L M Saksida; T W Robbins; T J Bussey Journal: Psychopharmacology (Berl) Date: 2015-07-24 Impact factor: 4.530
Authors: Caroline C Hilti; Tarik Delko; Ariane T Orosz; Kathrin Thomann; Stephan Ludewig; Mark A Geyer; Franz X Vollenweider; Joram Feldon; Katja Cattapan-Ludewig Journal: Neuropsychobiology Date: 2009-12-12 Impact factor: 2.328
Authors: Verity C Leeson; Trevor W Robbins; Elizabeth Matheson; Samuel B Hutton; María A Ron; Thomas R E Barnes; Eileen M Joyce Journal: Biol Psychiatry Date: 2009-07-03 Impact factor: 13.382
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Authors: V C Leeson; T W Robbins; C Franklin; M Harrison; I Harrison; M A Ron; T R E Barnes; E M Joyce Journal: Psychol Med Date: 2009-05-07 Impact factor: 7.723