Patterns and clinical correlates of neuropsychologic deficits in patients with schizophrenia

Patients with first-episode psychosis in northern Taiwan: neurocognitive performance and niacin response profile in comparison with schizophrenia patients of different familial loadings and relationship with clinical features

BACKGROUND

Examining patients with first-episode psychosis (FEP) provides opportunities to better understand the mechanism underlying these illnesses. By incorporating quantitative measures in FEP patients, we aimed to (1) determine the baseline distribution of clinical features; (2) examine the impairment magnitude of the quantitative measures by comparing with external controls and then the counterparts of schizophrenia patients of different familial loadings; and (3) evaluate whether these quantitative measures were associated with the baseline clinical features.

METHODS

Patients with FEP were recruited from one medical center, two regional psychiatric centers, and two private clinics in northern Taiwan with clinical features rated using the Positive and Negative Syndrome Scale (PANSS) and Personal and Social Performance (PSP) scale. Quantitative measurements included the Continuous Performance Test (CPT), Wisconsin Card Sorting Test (WCST), niacin response abnormality (NRA), and minor physical anomalies and craniofacial features (MPAs). To evaluate the relative performance of the quantitative measures in our FEP patients, four external comparison groups from previous studies were used, including three independent healthy controls for the CPT, WCST, and NRA, respectively, and one group of treatment-resistant schizophrenia patients for the MPAs. Additionally, patients from simplex families and patients from multiplex families were used to assess the magnitude of FEP patients' impairment on the CPT, WCST, and NRA.

RESULTS

Among the 80 patients with FEP recruited in this study (58% female, mean age = 25.6 years, mean duration of untreated psychosis = 132 days), the clinical severity was mild to moderate (mean PANSS score = 67.3; mean PSP score = 61.8). Patients exhibited both neurocognitive and niacin response impairments (mean Z-scores: -1.24 for NRA, - 1.06 for undegraded d', - 0.70 for degraded d', - 0.32 for categories achieved, and 0.44 for perseverative errors) but did not show MPAs indicative of treatment resistance. Among these quantitative measures, three of the four neurocognitive indices were correlated with the baseline clinical features, whereas NRA did not show such correlation.

CONCLUSIONS

This FEP study of Taiwanese patients revealed the presence of neurocognitive performance and niacin response and their different relationships with clinical features, rendering this sample useful for future follow-up and incorporation of multiomics investigation.

Neuropsychological dysfunctions among chronic schizophrenia patients, alcohol dependence cases, and normal subjects: A comparative study

AIM

The aim of this study is to assess the neuropsychological profiles of chronic schizophrenia and alcohol-dependent subjects.

MATERIALS AND METHODS

This hospital-based cross-sectional study included 30 chronic schizophrenia patients, 30 alcohol-dependent patients and 30-matched normal controls. Demographic and clinical data were collected on a self-designed pro forma. Positive and Negative Syndrome Scale (PANSS) and Severity of Alcohol Dependence Questionnaire (SADQ-C) were administered to chronic schizophrenia and alcohol-dependent patients, respectively. The AIIMS Comprehensive Neuropsychological Battery in Hindi (Adult Form) was used to assess neuropsychological dysfunctions.

RESULTS

Neuropsychological dysfunctions were found in 83.3% of chronic schizophrenia patients, 36.7% alcohol dependents and none of the normal subjects. In comparison to normal subjects, schizophrenia patients had significantly more dysfunctions in neuropsychological-domains such as motor, tactile, visual, receptive and expressive speech, reading, writing, arithmetic, memory, and intellectual processes. A significant positive correlation was found between the PANSS total score and T scores of most of the clinical scales except motor and visual scales; the PANSS general psychopathology score and T scores of most of the clinical scales except motor visual and pathognomonic scales; the PANSS negative score and T scores of most of the clinical scales except visual scale; and the PANSS positive score and T scores of receptive speech, arithmetic, and memory scales. In comparison to normal subjects, the alcohol dependents had significantly more dysfunctions in neuropsychological-domains such as motor, tactile, visual, receptive and expressive speech, reading, writing, arithmetic, and memory. A significant positive correlation was found between the SADQ total scale and T scores of clinical scales such as expressive speech, writing, arithmetic, intellectual processes, left hemisphere, and total battery scales.

CONCLUSIONS

Neuropsychological dysfunction was significantly more common and severe in chronic schizophrenia patients than in alcohol-dependent patients. In comparison to alcohol dependents, the chronic schizophrenia patients had more dysfunctions in neuropsychological-domains such as tactile, arithmetic, memory, and intellectual processes.

Development and Psychometric Properties of the Taiwan Odd-Even Number Sequencing Test: A Nonalphabetic Measure of Working Memory

Alphabetic working memory (WM) tests, such as the Wechsler Adult Intelligence Scale-III and IV Letter Number Sequencing, are not appropriate for nonalphabetic cultures. This study examined the psychometric properties of the Taiwan Odd-Even Number Sequencing Test (TOENST) and identified representative norms. The TOENST and other mental screening tasks were administered to 300 randomly selected healthy participants, 32 purposive sampling patients with schizophrenia, and 32 quota sampling controls. To investigate reliability and validity, a subset of the 300 healthy participants was randomly selected to receive a second TOENST ( n = 30) or conventional WM tests ( n = 42). The split-half reliability of the TOENST ranged from 0.69 to 0.95, and its test-retest reliability was 0.75. Criterion validity was demonstrated by significant correlations with conventional WM measures (all p < .05, except semantic verbal fluency), and construct validity was demonstrated by significant correlations with aging (main effect, F_10,259 = 10.99, p < .001). Normative data were established, and performance was significantly associated with age and education. TOENST scores of patients with schizophrenia were significantly lower and correlated with frontal lobe tests, but not demographical or clinical characteristics. The TOENST has adequate psychometric properties and clinical utility and is as a viable alternative WM task for nonalphabetic cultures.

Allocation Variable-Based Probabilistic Algorithm to Deal with Label Switching Problem in Bayesian Mixture Models

The label switching problem occurs as a result of the nonidentifiability of posterior distribution over various permutations of component labels when using Bayesian approach to estimate parameters in mixture models. In the cases where the number of components is fixed and known, we propose a relabelling algorithm, an allocation variable-based (denoted by AVP) probabilistic relabelling approach, to deal with label switching problem. We establish a model for the posterior distribution of allocation variables with label switching phenomenon. The AVP algorithm stochastically relabel the posterior samples according to the posterior probabilities of the established model. Some existing deterministic and other probabilistic algorithms are compared with AVP algorithm in simulation studies, and the success of the proposed approach is demonstrated in simulation studies and a real dataset.

Lower functioning predicts identification of psychosis risk screening status in help-seeking adolescents

AIM

There is some previous evidence suggesting that the risk state for psychosis is associated with decreased functioning ability, health-related quality of life (QoL), anxiety and depression. The aim of this study is to identify which factors predict psychosis risk screening status.

METHODS

The data were collected in Helsinki University Central Hospital, Finland, by an early intervention team. One hundred eighty-one help-seeking adolescents (mean age 15.3 years) completed questionnaires of QoL (16D), alcohol consumption (Alcohol Use Disorders Identification Test), anxiety (Beck Anxiety Inventory), hopelessness (BBeck Hopelessness Scale) and depression (Beck Depression Inventory II). Functioning ability was assessed by the Global Assessment of Functioning, whereas the PROD-screen was used to interview and assess risk symptoms for psychosis.

RESULTS

In a logistic regression analysis, a lower functioning ability explained independently (P = 0.006) psychosis risk screening status after age, gender, alcohol consumption, QoL, anxiety, hopelessness and depression symptoms were adjusted.

CONCLUSIONS

The present results suggest that lower functioning ability is associated independently with psychosis risk screening status. Hence, therapeutic input for those at risk should focus upon improving functioning.

Neurocognitive functioning of subjects with putative pre-psychotic states and early psychosis

BACKGROUND

The neurocognitive functioning of patients with schizophrenia is likely to decline at the early stage of the illness. More evidence is needed to determine whether deficits in certain domains of neurocognition precede the onset of illness and can predict the onset of psychosis.

METHODS

Subjects were recruited from the SOPRES study in Taiwan. A neuropsychological battery including the continuous performance test, Wisconsin Card Sorting Test, Wechsler Adult Intelligence Scale-Third Edition, Trail Making Tests, Mandarin version of the Verbal Fluency Test, and Wechsler Memory Scale-Third Edition, was applied at baseline and 1-year follow-up. Neurocognitive profiles derived from these tests were categorized into 9 domains for comparisons among subjects with different levels of clinical severity.

RESULTS

A total of 324 participants, including 49 with first episode psychosis (FEP), 53 with ultra-high risk (UHR), 42 with intermediate risk (IR), 43 with marginal risk (MR), and 137 normal controls completed a baseline assessment and 71% of the participants completed a 1-year follow-up assessment. The profiles of the UHR and IR groups were identical at baseline. Those who converted to FEP later on (UHR+) showed relatively poorer performance than non-converters (UHR-) at baseline. At follow-up the performance of UHR+ was compatible to that of FEP, while UHR- generally improved.

CONCLUSIONS

By including subjects with early putative pre-psychotic states, our study clarifies some inconsistencies about the timing and stability of changes in neurocognitive functioning that occur at the start of psychosis; it also raises questions regarding the feasibility of using neurocognitive deficits to predict the risks of transition to psychosis.

Neuropsychology, autobiographical memory, and hippocampal volume in "younger" and "older" patients with chronic schizophrenia

Despite a wide range of studies on neuropsychology in schizophrenia, autobiographical memory (AM) has been scarcely investigated in these patients. Hence, less is known about AM in older patients and hippocampal contribution to autobiographical memories of varying remoteness. Therefore, we investigated hippocampal volume and AM along with important neuropsychological domains in patients with chronic schizophrenia and the respective relationships between these parameters. We compared 25 older patients with chronic schizophrenia to 23 younger patients and an older healthy control group (N = 21) with respect to AM, additional neuropsychological parameters, and hippocampal volume. Personal episodic and semantic memory was investigated using a semi-structured interview. Additional neuropsychological parameters were assessed by using a battery of standard neuropsychological tests. Structural magnetic resonance imaging data were analyzed with an automated region-of-interest procedure. While hippocampal volume reduction and neuropsychological impairment were more pronounced in the older than in the younger patients, both groups showed equivalent reduced AM performance for recent personal episodes. In the patient group, significant correlations between left hippocampal volume and recent autobiographical episodes as well as personal semantic memories arose. Verbal memory and working memory were significantly correlated with right hippocampal volume; executive functions, however, were associated with bilateral hippocampal volumes. These findings underline the complexity of AM and its impairments in the course of schizophrenia in comparison to rather progressive neuropsychological deficits and address the importance of hippocampal contribution.

Bayesian inferences of latent class models with an unknown number of classes

This paper focuses on analyzing data collected in situations where investigators use multiple discrete indicators as surrogates, for example, a set of questionnaires. A very flexible latent class model is used for analysis. We propose a Bayesian framework to perform the joint estimation of the number of latent classes and model parameters. The proposed approach applies the reversible jump Markov chain Monte Carlo to analyze finite mixtures of multivariate multinomial distributions. In the paper, we also develop a procedure for the unique labeling of the classes. We have carried out a detailed sensitivity analysis for various hyperparameter specifications, which leads us to make standard default recommendations for the choice of priors. The usefulness of the proposed method is demonstrated through computer simulations and a study on subtypes of schizophrenia using the Positive and Negative Syndrome Scale (PANSS).

Health-related quality of life among adolescents: a comparison between subjects at risk for psychosis and other help seekers

AIM

Schizophrenia is a severe illness associated with poor health-related quality of life (HRQoL), and there is some evidence that a risk state for psychosis is associated with decreased HRQoL. The aim of the present study was to investigate group differences in HRQoL in help seekers at risk for psychosis and not at risk for psychosis.

METHODS

The data were collected by a Finnish early detection and intervention team at Helsinki University Central Hospital. A total of 202 help-seeking adolescents (110 girls, 92 boys; 11-22 years of age) were assessed with a PROD screen and HRQoL scale of 16D.

RESULTS

As the main result, subjects at risk for psychosis had a poorer HRQoL index than other help seekers (P < 0.001). An additional analysis of sub-items for the HRQoL at-risk group had poorer mean scores at a statistically significant level after Bonferroni correction for multiple tests in the following sub-items: vitality (P = 0.016), distress (P = 0.016), physical appearance (P < 0.001), school and hobbies (P = 0.016), friends (P = 0.048), mental function (P < 0.001) and depression (P < 0.001). In a logistic regression analysis of sub-items of the HRQoL scale, lower scores in the sub-item of mental function independently explained the at-risk status for psychosis (P = 0.009).

CONCLUSIONS

Adolescents at risk for psychosis have a poorer HRQoL index than other help seekers and they also differ in several sub-items, particularly in the lower scores in mental function. In the future, these findings should be considered in the care of adolescents at risk for psychosis.

Patient subgroups of schizophrenia based on the Positive and Negative Syndrome Scale: composition and transition between acute and subsided disease states

The present study focuses on schizophrenia patient subgroups with specific symptom pattern using the Positive and Negative Syndrome Scale (PANSS). In this report, we intend to (1) provide a more appropriate analytic method for exploring the subgroups based on PANSS data, (2) validate identified subgroups with external variables, and (3) estimate probabilities of subgroup changes between 2 disease states. The analyzed data include 219 acute-state patients who had completed the PANSS within 1 week of index admission and 225 subsided-state patients who were living in the community and under family care. Regression extension of latent class analysis was performed. We found that acute schizophrenia can be classified into 4 subgroups--whole syndrome, whole syndrome without hostility, partial syndrome with negative symptoms, and partial syndrome with pure reality distortion--and that subsided schizophrenia can be classified into 3 subgroups--florid symptom, marked negative, and remitted. Patients of the whole syndrome, whole syndrome without hostility, partial syndrome with negative symptoms, and partial syndrome with pure reality distortion subgroups at the acute state were most likely to transit to the florid symptom (61%), florid symptom (48%), marked negative (42%), and remitted (56%) subgroups at the subsided state, respectively. Significant relationships of obtained subgroups with sociodemographic variables and neurocognitive variables were identified. These results of different subgroups will provide the background for facilitating current molecular, genetic, and neurobiological studies of schizophrenia.

Associations between number of different type of care meetings with social network and improvement in mental well-being in adolescents at risk of first-episode psychosis

AIM

As research in the care of people at risk of developing first-episode psychosis has mostly focused on cognitive behavioural therapy and antipsychotic medication, little is known about associations between changes in mental well-being and effect of people participating in the care.

METHODS

Multiprofessional early intervention team met with adolescents who are at risk of psychosis, including coworkers and their families. Correlations were calculated between change scores in prepsychotic, functioning ability, quality of life (QoL), depression and anxiety scales, and number of family, coworker and adolescent-participating social network meetings, and total number of social network meetings during the care.

RESULTS

Larger change scores in functioning ability were positively associated with the number of social network meetings with participating coworker (P = 0.041), but not with other types of participant meetings. Larger change scores in prepsychotic symptoms were positively associated with the number of meetings where the adolescent was participating (P = 0.001), the number of network meetings where the coworker was participating (P = 0.007) and the number of all meetings (P = 0.001). The number of any other type of meetings did not associate with change scores in QoL, depression and anxiety.

CONCLUSION

According to the present results, adolescents at risk of psychosis seem to benefit from the inclusion of coworkers from the adolescents' natural surroundings in care; this could help to increase functioning ability. Different combinations of meetings, such as larger number of total meetings, larger number of meetings with the adolescent and larger number of meetings with coworkers from the adolescents' natural surroundings, seem to associate with stronger decrease in pre-psychotic symptoms.

Poor functioning ability is associated with high risk of developing psychosis in adolescents

BACKGROUND

While functioning ability, quality of life (QoL) and depression are widely studied phenomena in schizophrenia, little is known about functioning ability, QoL and depression, especially among adolescents at high risk of developing first-episode psychosis.

AIM

To investigate associations between high risk of developing psychosis and functioning ability, depression and QoL among adolescents.

METHODS

The data was collected by an early intervention team in Espoo, Finland, between 1 January 2007 and 31 May 2008. Subjects at high risk of developing psychosis were compared with subjects not at high risk in terms of functioning ability (GAF), QoL (16D) and depressive symptoms (RBDI) in a cross-sectional setting. The study was conducted with 80 adolescents (mean age 14.7, range 12-18 years).

RESULTS

Those at high risk of developing psychosis had significantly lower and poorer scores in functioning ability (53.4 vs. 58.4, P=0.006), had higher and poorer scores in QoL (10.81 vs. 7.05, P=0.002) and higher and poorer scores in depression (8.95 vs. 4.76, P=0.001) than those who did not meet the criteria of being at high risk of developing psychosis. Poorer functioning ability independently explained being at high risk of developing psychosis at a statistically significant level (P=0.021) in a logistic regression analysis after age, gender, depression and QoL were adjusted for.

CONCLUSIONS

Poor functioning ability seems to be associated with high risk of developing psychosis among adolescents.

Affect recognition as an independent social function determinant in schizophrenia

INTRODUCTION

Facial affect recognition deficits may represent specific deficits and contribute to social dysfunction in patients with schizophrenia. Whether their impacts on social dysfunction are independent to those caused by deficits in basic neurocognition and clinical symptoms needs to be further delineated.

METHOD

Association patterns between affect recognition and basic neurocognitive abilities in 40 acute and 33 stable patients with schizophrenia were compared to explore whether their interrelationships changed across clinical stages. The independent contribution of affect recognition deficits to social dysfunction was explored by multivariate models controlling for general intellectual ability, basic neurocognition, and clinical symptoms.

RESULTS

Affect recognition deficits were associated with social role performances, self-care, and contributed independently to global social functioning in stable patients but not in acute patients. Conversely, affect recognition deficits were associated with impaired basic neurocognitions in acute patients but not in stable patients.

CONCLUSION

In stabilized community patients with schizophrenia, affect recognition deficits were relatively independent to basic neurocognition and had significant social functional consequences.

What do we know about neuropsychological aspects of schizophrenia?

Application of a neuropsychological perspective to the study of schizophrenia has established a number of important facts about this disorder. Some of the key findings from the existing literature are that, while neurocognitive impairment is present in most, if not all, persons with schizophrenia, there is both substantial interpatient heterogeneity and remarkable within-patient stability of cognitive function over the long-term course of the illness. Such findings have contributed to the firm establishment of neurobiologic models of schizophrenia, and thereby help to reduce the social stigma that was sometimes associated with purely psychogenic models popular during parts of the 20th century. Neuropsychological studies in recent decades have established the primacy of cognitive functions over psychopathologic symptoms as determinants of functional capacity and independence in everyday functioning. Although the cognitive benefits of both conventional and even second generation antipsychotic medications appear marginal at best, recognition of the primacy of cognitive deficits as determinants of functional disability in schizophrenia has catalyzed recent efforts to develop targeted treatments for the cognitive deficits of this disorder. Despite these accomplishments, however, some issues remain to be resolved. Efforts to firmly establish the specific neurocognitive/neuropathologic systems responsible for schizophrenia remain elusive, as do efforts to definitively demonstrate the specific cognitive deficits underlying specific forms of functional impairment. Further progress may be fostered by recent initiatives to integrate neuropsychological studies with experimental neuroscience, perhaps leading to measures of deficits in cognitive processes more clearly associated with specific, identifiable brain systems.

Intervention to improve level of overall functioning and mental condition of adolescents at high risk of developing first-episode psychosis in Finland

AIM

Being at high risk of developing psychosis has been suggested to be a result of a combination of acute life stressors and trait-like vulnerability to psychosis. Reducing levels of stress could support overall functioning and mental condition in those at risk.

METHODS

The Jorvi Early Psychosis Recognition and Intervention (JERI) project at Helsinki University Central Hospital, Jorvi Hospital, Finland, is an early intervention team for adolescents at risk of developing first-episode psychosis. The project is based on the idea of multiprofessional, community, home, family and network-oriented, stress-reducing, overall functioning-supporting, low-threshold care. The JERI team meets multiprofessionally with adolescents in their natural surroundings, for example, at school or at home, together with their parents, network and community co-worker, who has originally contacted the JERI team because of unclear mental health problems. Subjects were assessed with the PROD-prodromal screen to identify those at risk of developing first-episode psychosis.

RESULTS

Statistically significant difference between baseline and follow-up measures was found in at risk subjects (n = 28) in scales of overall functioning (P = 0.000), depression (P = 0.001), anxiety (P = 0.001), quality of life (QOL) and pre-psychotic symptoms.

CONCLUSIONS

JERI-type intervention may improve level of overall functioning and support mental condition in adolescents at risk of developing first-episode psychosis, even though further study with larger numbers of subjects, with a control group and with a longer follow-up time, is needed.