Neuropsychological test scores and clinical response to neuroleptic drugs in schizophrenic patients

Cognitive factors for predicting treatment response in schizophrenic patients: one-year follow-up study

OBJECTIVE

This study was conducted to investigate the cognitive factors that can longitudinally predict the response to treatment in patients with schizophrenia.

METHODS

The subjects were 49 patients with schizophrenia who were newly hospitalized in an acute psychiatry ward and had not been treated with medication for at least 8 weeks prior to the study. The symptoms and cognitive functions of the patients were evaluated at baseline before treatment (T0), at eight weeks after treatment (T1), and one year after treatment (T2). Clinical symptoms were assessed using the PANSS, and cognitive functions were estimated using the Vigilance Test, Cognitrone Test, Wisconsin Card Sorting Test (WCST), and the Korean version of the Memory Assessment Scales (K-MAS).

RESULTS

The patient group showed marked impairments in cognitive function when compared to the normal group, but the patients' clinical symptoms and cognitive functions improved after drug treatment. The patients also showed consistent improvement in verbal and nonverbal memory function as time progressed. Furthermore, there was a significant correlation between clinical symptoms and cognitive functions in the patient group. The cognitive variables that best predicted treatment response and prognosis were total errors on the WCST and immediate list recall component of the K-MAS. It was also shown that the number of total errors on the WCST was a better cognitive predictor than the number of errors in immediate recall.

CONCLUSION

The results of the present study show that the neurocognitive functions of patients with schizophrenia can be stabilized with treatment intervention, that treatment response is related to improvement in cognitive function, and that cognitive domains, especially executive function, can predict treatment response and prognosis in patients with schizophrenia.

Neurocognition and community outcome in schizophrenia: long-term predictive validity

The present study examined the predictive validity of neuropsychological measures to functional outcome in 26 schizophrenic patients 15-plus year post-testing. Outcome measures included score on the Resource Associated Functional Level Scale (RAFLS), number of state hospital admissions, and total duration of state hospital inpatient stay. Results of several stepwise multiple regressions revealed that verbal memory significantly predicted RAFLS score, accounting for nearly half of the variance. Trails B significantly predicted duration of state hospital inpatient status. Discussion focused on the utility of these measures for clinicians and system planners.

SPECT imaging, clinical features, and cognition before and after low doses of amisulpride in schizophrenic patients with the deficit syndrome

The aim of the study was to examine the action of low-dose amisulpride (100 mg/d), an atypical antipsychotic from the benzamide class with a high affinity for the D2 and D3 dopamine receptors, given for 4 weeks in 19 schizophrenic patients with the deficit syndrome, in terms of clinical response, modifications in their cognitive performance and changes in brain perfusion values. A secondary objective was to distinguish between primary and secondary deficit, according to Carpenter's definition. Both efficacy and a relatively low rate of side effects of low-dose amisulpride in the deficit forms of schizophrenia were found as expected from earlier placebo-controlled studies. Our study found significant changes in the cerebral blood flow, before and after treatment, more marked in the frontal area and particularly in the dorso-lateral frontal area. A significant improvement of cognitive function was found after treatment, without a link to any particular changes in a loco-regional perfusion value. Finally, a distinction between primary and secondary deficit showed a higher percentage of clinical improvement in the patients with a secondary deficit. The psychometric and cerebral perfusion changes were no different in the two groups.

Longitudinal study of cognitive function in first-episode and recent-onset schizophrenia

OBJECTIVE

Whether cognitive function in schizophrenia deteriorates, improves, or remains stable is a crucial question. Few studies have examined the longitudinal stability of cognitive function and the relationship between cognitive performance and clinical symptoms over time in a cohort of well-treated patients with schizophrenia.

METHOD

In the present study, 54 patients with first-episode and recent-onset schizophrenia completed a comprehensive cognitive test battery and were rated on symptom measures at index hospitalization and again after 5 years.

RESULTS

Performance IQ and full-scale IQ significantly improved, whereas verbal IQ did not change. Group performance improved on some of the neuropsychological tests, including the Circle A letter-cancellation task, free recall of logical memory test score, and the Wisconsin Card Sorting Test. Mean finger-tapping performance worsened over time, whereas performance on other neuropsychological tests did not change. Negative, psychotic, and disorganized symptoms significantly improved over the time period. Changes in negative symptoms were correlated with performance changes in verbal IQ and full-scale IQ but not performance IQ. Improvement in verbal cognition was observed when negative symptoms improved. Psychotic and disorganized symptom dimensions were not correlated with any IQ measure.

CONCLUSIONS

These results indicate that in a cohort of young patients receiving neuroleptic treatment early in their illness, cognitive performance does not deteriorate--and may improve. Only one of the three symptom 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.

Stability of cognitive functioning early in the course of schizophrenia

This study evaluated the longitudinal course of neuropsychological deficits in a group of patients with new or recent onset schizophrenia. Thirty-five inpatients with DSM-III-R diagnoses of schizophrenia were administered a comprehensive battery of neuropsychological tests during their index hospitalization, and either 1 or 2 years after intake. Cognitive function remained stable in most domains, including motor speed, verbal and nonverbal memory, and verbal learning. Significant improvement in neuropsychological performance was observed on a task of complex attention (Trails B) and a set response shifting task (Stroop). These improvements were correlated with changes in clinical symptoms, but not with changes in medication dose. These findings suggest that most of the neuropsychological functioning in schizophrenia is stable over the first few years of the illness. Moreover, those neuropsychological deficits that remain unchanging appear to be independent of significant change in clinical symptoms, suggesting they may be a trait of the illness. However, a small subset of functions such as complex attention and response inhibition appear to fluctuate with time, and in particular, with clinical symptomatology, and may be considered 'state' dependent.