Rationale
Cognitive deficits are now recognised as a major symptom of
schizophrenia with a number of studies reporting profound deficits in
cognitive function in both chronic and first episode patients. Recent
advances in cognitive remediation therapy have provided the opportunity
for patients to improve their cognitive function and therefore improve their
functional outcome.
Aim
The aim of the present study was to investigate cognitive deficits using the
Cambridge Neuropsychological Test Automated Battery (CANTAB®) in
first episode psychosis and chronic schizophrenia patients. In the first
episode population the effect of ethnicity on cognition was also examined.
In the chronic schizophrenia study comparisons between severity of
deficits with first episode psychosis patients were also made. The effects
of cognitive remediation therapy were also examined in a sample of first
episode patients.
Methods
A total of 35 patients and 30 healthy controls were recruited into the first
episode study, 17 patients and 17 controls into the chronic schizophrenia
study and 11 patients into the cognitive remediation study. The first
episode psychosis patients were recruited from the Bradford and Airedale
Early Intervention Service and the chronic patients from the Leeds
Partnership NHS Foundation Trust. The control subjects were matched as
closely as possible in terms of intelligence and demographics to the
patient groups. The Wechsler Test of Adult Reading (WTAR) was used to
estimate subjects pre-morbid IQ. The severity of symptoms was assessed
using the Positive and Negative Syndrome Scale (PANSS). All subjects
who took part in the study completed a comprehensive battery of
neuropsychological tests from the CANTAB®. Patients in the cognitive
remediation study participated in group therapy sessions using X-cog®.
Results
There were no significant differences found between There were no significant differences found between patients and controls
in relation to intelligence or demographics in all studies. The effect of
ethnicity was shown to be not significant in the first episode study. Results
show that patients performed significantly worse than controls across all
iv
cognitive domains tested in all studies. A correlation between negative
symptoms and executive function was found in both first episode and
chronic schizophrenia patients. Comparisons between first episode
psychosis and chronic schizophrenia patients in cognition showed no
significant differences, however significant differences were found in levels
of negative symptoms and age between the two groups with chronic
patients scoring higher on negative symptoms and being older. In the
cognitive remediation study a significant improvement was observed in
patients in the domain of executive function and a reduction in negative
symptoms following completion of the intervention.
Conclusion
First episode and chronic schizophrenia patients display significant
cognitive deficits across all domains when tested using the CANTAB®.
Some of these deficits appear to be independent of the length of the
illness but dependent on negative symptoms. This study demonstrates
that cognitive deficits exist across all patient groups regardless of age,
gender, pre-morbid IQ, years in education and ethnicity. Cognitive
remediation therapy has also been shown to be effective in improving
cognitive functioning in patients.
| Identifer | oai:union.ndltd.org:BRADFORD/oai:bradscholars.brad.ac.uk:10454/5689 |
| Date | January 2012 |
| Creators | Saleem, Majid M. |
| Contributors | Neill, Joanna C. |
| Publisher | University of Bradford, School of Pharmacy |
| Source Sets | Bradford Scholars |
| Language | English |
| Detected Language | English |
| Type | Thesis, doctoral, PhD |
| Rights | <a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/3.0/"><img alt="Creative Commons License" style="border-width:0" src="http://i.creativecommons.org/l/by-nc-nd/3.0/88x31.png" /></a><br />The University of Bradford theses are licenced under a <a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/3.0/">Creative Commons Licence</a>. |
Page generated in 0.0021 seconds