Exploring the relationship of cognitive function with and without COVID-19 recovered schizophrenic patients

Background

The Coronavirus disease 2019 (COVID-19) is linked to the deterioration of cognitive function among individuals suffering from schizophrenia. The purpose of this study was to compare the cognitive performance of schizophrenic patients before and after COVID-19.

Methods

A longitudinal cohort study involving a sample of 219 individuals diagnosed with schizophrenia was enrolled between June 2022 and May 2023. The participants were split into two groups infected with COVID-19 (n = 165) and not infected with COVID-19 (n = 54). The data were gathered via a questionnaire on demographic characteristics, the Brief Assessment of Cognition in Schizophrenia (BACS), the Positive and Negative Syndrome Scale (PANSS), the Calgary Depression Scale for Schizophrenia (CDSS), the Activities of Daily Living (ADL) scale, and the Insomnia Severity Index (ISI).

Results

The repeated-measures ANOVA showed that Among patients diagnosed with COVID-19, there was a deterioration in global cognitive function (before COVID-19 = -2.45 vs. after COVID-19 = -3.02, p = 0.007), working memory (before COVID-19 = -2.76 vs. after COVID-19 = -3.34, p < 0.00 1), motor speed (before COVID-19 = -1.64 vs. after COVID-19 = -2.12, p < 0.001), attention and speed of information processing (before COVID-19 = -1.93 vs. after COVID-19 = -1.16, p = 0.008). multi-variable analysis showed that several factors as having a secondary grade of education (β = 0.434), experiencing insomnia (β = 0.411)and the interaction between COVID-19 diagnosis and cognition at baseline (β = 0.796) were significantly associated with cognitive deficits. At the same time, no significant associations were found between global cognition and clinical symptoms, autonomy, or depression (p > 0.05).

Conclusion

The COVID-19 pandemic has significantly impacted various cognitive functions, such as verbal memory, working memory, and global cognition. Insomnia has been identified as the predominant determinant of cognitive impairment, alongside the confirmation of a COVID-19 diagnosis. Additional research is imperative to elucidate the diversification of cognitive functionality observed in individuals diagnosed with schizophrenia who have acquired COVID-19.

[An effect of antipsychotic and anticholinergic treatment on cognitive function in patients with schizophrenia]

OBJECTIVE

To reveal the relationships between antipsychotic and anticholinergic drugs and cognitive functions in patients with schizophrenia.

MATERIAL AND METHODS

The observational prospective study was conducted at the Bekhterev National Medical Center of Psychiatry and Neurology. The study involved 41 patients (22 men and 19 women) with paranoid schizophrenia, according to ICD 10 criteria, aged 30.12±8.24 years on stable antipsychotic monotherapy or in combination with anticholinergic drug (trihexiphenidyl). Cognitive functions were assessed using the «Brief Assessment of Cognitive Function in Patients with Schizophrenia» (BACS) scale, severity of mental state and extrapyramidal disturbances were measured using the «Positive and Negative Syndrome Scale (PANSS) and the Simpson-Angus Scale for Assessment of Extrapyramidal Side Effects (SAS). All examination procedures were performed twice at weeks 2 and 8 of therapy. Patients were divided into 2 groups according to the type of antipsychotic therapy. Twelve patients received first generation antipsychotics (FGAs) (group 1), 29 patients received second generation antipsychotics (SGAs) (group 2).

RESULTS

Patients receiving SGAs had a significant decrease in the overall SAS score at week 8 of therapy compared with data at week 2, and there was an improvement in cognitive function, unlike patients receiving FGAs. There were also changes on BACS tests the digit sequencing (V=51.5, p=0.007), token motor task (V=75.5, p=0.007) and Tower of London (V=52, p=0.027) only in patients of group 2.

CONCLUSION

The improved tolerance to the drug, as well as cognitive measures, was shown in patients taking SGAs by week 8. Our study confirms the importance of adhering to the minimum effective dose of antipsychotic drugs for the treatment of schizophrenia to prevent cognitive impairment, and to give preference to SGAs in the choice of treatment.

Effect of antipsychotic dose reduction on cognitive function in schizophrenia

Cognitive deficits are predictors of social functioning but remain an unmet therapeutic challenge. While lowering the antipsychotics carries a risk of relapse, it possibly has a beneficial effect on cognitive function. However, this has not been examined in a real-world setting. A prospective naturalistic 6-month follow-up study (n = 71) was conducted with patients between 18 and 45 years in their first five years of illness and the maintenance phase of the treatment. Brief Assessment of Cognition in Schizophrenia (BACS) was administered to assess cognitive functions. Patients were divided into three groups based on the change in dose of antipsychotics. The data were analyzed using linear mixed-effects modeling (LMEM) to examine the group differences. At the end of six months, those with decreased antipsychotic dose had significant improvement in BACS total score, token test, and symbol coding compared to those with no change in the dose of antipsychotic. Reducing the dose of antipsychotics during the maintenance phase was associated with improved cognitive functions without an increased risk of relapse. Antipsychotic dose reduction may be better than discontinuation as the relapse risk is higher with the discontinuation strategy. Clinicians must balance the improvements in cognitive functions and relapse risk.

Cross-cultural adaptation and validation of the Arabic version of the BACS scale (the brief assessment of cognition in schizophrenia) among chronic schizophrenic inpatients

BACKGROUND

Assessment of cognitive disorders in schizophrenia is becoming a part of clinical and research practice by using batteries that differ widely in their content. The Brief Assessment of Cognition in Schizophrenia (BACS) was developed to cover the main cognitive deficits of schizophrenia. The objective of this study was to assess concurrent validity of the Arabic version of the BACS with a standard neurocognitive battery of tests in Lebanese patients with schizophrenia and healthy controls.

METHODS

A sample of 120 stable inpatients diagnosed with schizophrenia and 60 healthy controls received the Arabic version of the BACS in a first session, and a standard battery in a second session.

RESULTS

Mean duration of completion for the BACS was 31.2 ± 5.4 min in patients with schizophrenia. All tests demonstrated significant differences between controls and patients (p < .01). Principal components analysis demonstrated that a one-factor solution best fits our dataset (64.8% of the variance). High Cronbach alpha was found (.85). The BACS composite scores were significantly correlated with the standard battery composite scores in patients (r = .73, p < .001) and healthy controls (r = .78, p < .001). Also, correlation analysis between the BACS sub-scores and the standard battery sub-scores showed significant results (p < .05).

CONCLUSION

Results showed that the Arabic version of the BACS demonstrated high ability to discriminate patients with schizophrenia from healthy controls and it is a useful tool for assessing cognition in patients with schizophrenia and could be used in clinical practice in Lebanon.

Cognitive deficit in patients with paranoid schizophrenia: Its clinical and laboratory correlates

The aim of this study was to search for correlates of cognitive impairment in patients with paranoid schizophrenia among clinical, demographic, anamnestic and biochemical markers (NSE, S100B protein, BDNF, hs-CRP). Patients with paranoid schizophrenia (n=125) were examined using the Brief Assessment of Cognitive Function in Schizophrenia, the Rey-Osterrieth Complex Figure task, and a number of clinical scales including the Positive and Negative Syndrome Scale. The majority of patients demonstrated cognitive impairment. The type of impairment was highly heterogeneous and individual. Relationships were found between the degree of executive functioning and family history of mental illness; working memory and age of onset of schizophrenia; and visual memory and psychopathological symptomatology. Negative and affective symptoms were not significantly associated with cognitive functioning. Treatment with first generation antipsychotics was associated with a more frequent impairment of motor skills, and concomitant anticholinergic drugs, with reduced accuracy. Use of second-generation antipsychotics only was associated with better accuracy, working memory and speech fluency. Among the patients, 21.4% had signs of a systemic inflammatory response, indicating a possible role of inflammatory response in the development of schizophrenia. CRP, S100B and NSE levels reflected features of the course of illness and therapeutic response. Patients with lower concentrations of BDNF were characterized by lower processing speeds.

Cognitive function, treatment response to lithium, and social functioning in Japanese patients with bipolar disorder

OBJECTIVES

Patients with bipolar disorder often suffer from cognitive impairment that significantly influences their functional outcome. However, it remains unknown whether lithium has a central role in cognition and functional outcome. We examined whether cognition and functional outcome were predicted by demographic and clinical variables, including the response to lithium, in lithium-treated patients with bipolar disorder.

METHODS

We evaluated 96 lithium-treated euthymic patients with bipolar disorder and 196 age- and-gender-matched healthy controls, using the Brief Assessment of Cognition in Schizophrenia (BACS). The patients were also assessed using the Social Functioning Scale (SFS) and "The Retrospective Criteria of Long-Term Treatment Response in Research Subjects with Bipolar Disorder" (Alda) scale, which was evaluated as either a continuous measure of the total scale or a dichotomous criterion.

RESULTS

Multiple regression analysis revealed two key findings: first, that the premorbid intelligence quotient, age, and number of mood episodes were predictors of the BACS composite score; and, second, that the BACS composite score, negative symptoms, and continuous measure on the total Alda scale (but not its dichotomy) predicted the total SFS score. Structural equation modeling (SEM) was used to confirm these findings, and additionally revealed that the Alda scale was significantly associated with negative symptoms and also the number of mood episodes, regardless of how it was evaluated.

CONCLUSIONS

SEM delineated how demographic and clinical variables, cognitive performance, and response to lithium treatment were causally associated with, and converged on, social function. The putative role of the Alda scale for social function warrants further study.

Validation of the Persian version of the Schizophrenia Cognition Rating Scale (SCoRS) in patients with schizophrenia

The Schizophrenia Cognition Rating Scale (SCoRS) is an interview-based assessment of cognition that involves interviews with patients and informants. The SCoRS has shown good reliability, validity, and sensitivity to cognitive impairment in schizophrenia, with the advantage of brief administration and scoring time. The present study aimed to test the concurrent validity of the Persian version of the SCoRS. A group of 35 patients with schizophrenia and a group of 35 healthy controls received the Persian-SCoRS in the first session, and a standardized performance-based cognitive battery, the Brief Assessment of Cognition in Schizophrenia (BACS), in the second session.Our results indicated that the Persian version of the SCoRS was sensitive to cognitive impairment in the patients. The Persian SCoRS global rating was significantly associated with the composite score generated from the Persian version of the BACS and predicted functional outcomes as measured by Global Assessment of Functioning (GAF) and World Health Organization Quality of Life (WHO QOL). A Persian version of the SCoRS, an interview based measure of cognition that included informants, is related to cognitive performance and global functioning.

Validation of the tablet-administered Brief Assessment of Cognition (BAC App)

Computerized tests benefit from automated scoring procedures and standardized administration instructions. These methods can reduce the potential for rater error. However, especially in patients with severe mental illnesses, the equivalency of traditional and tablet-based tests cannot be assumed. The Brief Assessment of Cognition in Schizophrenia (BACS) is a pen-and-paper cognitive assessment tool that has been used in hundreds of research studies and clinical trials, and has normative data available for generating age- and gender-corrected standardized scores. A tablet-based version of the BACS called the BAC App has been developed. This study compared performance on the BACS and the BAC App in patients with schizophrenia and healthy controls. Test equivalency was assessed, and the applicability of paper-based normative data was evaluated. Results demonstrated the distributions of standardized composite scores for the tablet-based BAC App and the pen-and-paper BACS were indistinguishable, and the between-methods mean differences were not statistically significant. The discrimination between patients and controls was similarly robust. The between-methods correlations for individual measures in patients were r>0.70 for most subtests. When data from the Token Motor Test was omitted, the between-methods correlation of composite scores was r=0.88 (df=48; p<0.001) in healthy controls and r=0.89 (df=46; p<0.001) in patients, consistent with the test-retest reliability of each measure. Taken together, results indicate that the tablet-based BAC App generates results consistent with the traditional pen-and-paper BACS, and support the notion that the BAC App is appropriate for use in clinical trials and clinical practice.

Associations between daily living skills, cognition, and real-world functioning across stages of schizophrenia; a study with the Schizophrenia Cognition Rating Scale Japanese version

Cognitive function is impaired in patients with schizophrenia-spectrum disorders, even in their prodromal stages. Specifically, the assessment of cognitive abilities related to daily-living functioning, or functional capacity, is important to predict long-term outcome. In this study, we sought to determine the validity of the Schizophrenia Cognition Rating Scale (SCoRS) Japanese version, an interview-based measure of cognition relevant to functional capacity (i.e. co-primary measure). For this purpose, we examined the relationship of SCoRS scores with performance on the Brief Assessment of Cognition in Schizophrenia (BACS) Japanese version, a standard neuropsychological test battery, and the Social and Occupational Functioning Assessment Scale (SOFAS), an interview-based social function scale. Subjects for this study (n = 294) included 38 patients with first episode schizophrenia (FES), 135 with chronic schizophrenia (CS), 102 with at-risk mental state (ARMS) and 19 with other psychiatric disorders with psychosis. SCoRS scores showed a significant relationship with SOFAS scores for the entire subjects. Also, performance on the BACS was significantly correlated with SCoRS scores. These associations were also noted within each diagnosis (FES, CS, ARMS). These results indicate the utility of SCoRS as a measure of functional capacity that is associated both with cognitive function and real-world functional outcome in subjects with schizophrenia-spectrum disorders.

Successful evaluation of cognitive function and the nature of cognitive deficits among people with schizophrenia in clinical rehabilitation settings

OBJECTIVES

Despite possessing considerable relevance for planning and delivery of effective rehabilitation interventions, systematic evaluation of cognitive function is often ignored in clinical practice. This paper describes a successful method for measuring cognitive function and the nature of cognitive deficits (CD) in people with schizophrenia admitted to psychiatric rehabilitation services.

METHODS

Data on the cognitive functioning of consecutive patients with schizophrenia / schizoaffective disorder admitted during a 5-year period to a public in-patient rehabilitation facility was collated retrospectively and analysed. The Brief Assessment of Cognition in Schizophrenia (BACS) was used to evaluate cognitive function.

RESULTS

It was possible to administer the BACS to 122 of 135 consecutive admissions. The mean composite score on the BACS was 1.8 standard deviations below the norm, and 43% had moderate or severe CD. The BACS sub-tests of list learning and symbol coding revealed more severe deficits.

CONCLUSIONS

The study indicates that evaluation of cognitive function using brief instruments is feasible in psychiatric rehabilitation settings. Global and domain-specific CD were prevalent among people with schizophrenia. In view of the strong association of cognitive functioning with community functioning and rehabilitation outcomes, further studies exploring the feasibility and utility of routinely evaluating cognitive function are warranted.

Neurocognitive features in male patients with schizophrenia exhibiting serious violence: a case control study

BACKGROUND

The relationship between violence and neurocognitive function in schizophrenia is unclear. We examined the backgrounds and neurocognitive functions of violent and nonviolent patients with schizophrenia to identify factors associated with serious violence.

METHODS

Thirty male patients with schizophrenia who were hospitalized after committing serious violent acts were compared with 24 hospitalized male patients with schizophrenia and no history of violence. We evaluated psychiatric symptoms using the Positive and Negative Syndrome Scale (PANSS) and neurocognitive functions using the Brief Assessment of Cognition in Schizophrenia (BACS)-Japanese version.

RESULTS

Repeated-measures analyses of variance on BACS subcomponents z-scores showed that the violent and control groups had different neuropsychological profiles at trend level (p = 0.095). Post hoc analyses of variance indicated that the violent group had significantly better working memory and executive function than the control group. In post hoc ANOVAs also controlling for the effect of the presence of substance abuse on cognitive function, violent or nonviolent group had a significant main effect on executive function but not on working memory.

CONCLUSIONS

Patient with violent or non-violent schizophrenia have distinct neuropsychological profiles. These results may help develop improved psychosocial treatments.

Cognitive deficit awareness in schizophrenia: absent, intact, or somewhere in-between?

INTRODUCTION

Cognitive impairment is a pervasive feature of schizophrenia, and is a major determinant of the functional disability that is characteristic of the disorder. However, research investigating whether patients with schizophrenia show a deficit awareness remains unclear. The present study aimed to replicate and extend previous research comparing subjective and objective measures of cognition.

METHODS

. Thirty patients with a diagnosis of schizophrenia or schizoaffective disorder were administered the subjectively assessed Schizophrenia Cognitive Rating Scale (SCoRS) and the objective Brief Assessment of Cognition in Schizophrenia (BACS), which each assess overall global functioning and four specific neurocognitive domains (i.e., Verbal Memory, Working Memory, Processing Speed, and Reasoning and Problem Solving). Because deficit awareness may influence the likelihood of patients engaging in treatments designed to improve cognitive functioning, patients' attitudes towards such therapies were also contrasted with these subjective and objective measures of cognitive functioning.

RESULTS

Patients' subjective appraisals did not significantly correlate with the objective neuropsychological assessments for global functioning or any specific neurocognitive domains. However, patients accurately deduced that their memory domains were more impaired than the other domains, and there was a trend for patients to exaggerate their Reasoning and Problem Solving deficits. This suggests that patients show some level of deficit awareness, when overestimating "deficits" for domains that are not impaired. Finally subjective, but not objective, measures of cognitive functioning correlated significantly with willingness to participate in cognitive-enhancing therapies.

CONCLUSIONS

These results suggest that although patients' perceptions of their cognitive function are no substitute for objective neuropsychological test data, patients do possess a level of deficit awareness which may, in turn, influence willingness to participate in interventions such as cognitive rehabilitation.

Using the Brief Assessment of Cognition in Schizophrenia (BACS) to assess cognitive impairment in older patients with schizophrenia and bipolar disorder

OBJECTIVES

A growing body of evidence suggests that impairment in cognitive functioning is an important clinical feature of both schizophrenia and bipolar disorder, and that these cognitive alterations worsen with age. Although cognitive assessments are increasingly becoming a part of research and clinical practice in schizophrenia, a standardized and easily administered test battery for elderly patients with bipolar disorder is still lacking. The Brief Assessment of Cognition in Schizophrenia (BACS) captures those domains of cognition that are the most severely affected in patients with schizophrenia and the most strongly correlated with functional outcome. The primary aim of our study was to investigate the clinical usefulness of the BACS in assessing cognitive functioning in elderly euthymic patients with bipolar disorder, and to compare their cognitive profile to that of elderly patients with schizophrenia.

METHODS

Elderly euthymic patients with bipolar disorder or schizophrenia were assessed using the BACS and a standard cognitive test battery.

RESULTS

Fifty-seven elderly patients (aged 60 years and older) with bipolar disorder (n = 42) or schizophrenia (n = 15) were invited to participate. All of the patients were assessed by the BACS as being cognitively impaired. The patients with bipolar disorder scored significantly higher on the global scale and the verbal memory and attention sub-scores of the BACS than the patients with schizophrenia.

DISCUSSION

The BACS appears to be a feasible and informative cognitive assessment tool for elderly patients with bipolar disorder. We believe that these preliminary results merit further investigation.

Language-dependent performance on the letter fluency task in patients with schizophrenia

Two types of verbal fluency tasks (letter fluency task; LFT, category fluency task; CFT) have been widely used to assess cognitive function in people with psychiatric diseases including schizophrenia. The task demand of the LFT is considered to vary across languages, as the cognitive process largely relies on sound and writing systems. Specifically, a sound unit for a letter (s) and a manner of association between them are assumed to be related with the performance. In the current study, three analyses have been conducted to examine this issue, using Japanese, Turkish, and English-speaking patients with schizophrenia. It was hypothesized that severity of letter fluency impairment would be in the order of Japanese, Turkish, and English speaking patients according to the inflexibility of a word search. First, performance on the LFT and the CFT was compared among Japanese (N=40), Turkish (N=30), and the US (N=31) patients (Analysis 1). A significant difference was found between the US and other two groups only in the LFT. Second, verbal fluency performance was compared between Japanese and Turkish patients by contrasting the degree of disassociations from normal controls (Japanese: N=20, Turkish: N=30) (Analysis 2). In Japanese patients, performance on the LFT was more severely impaired compared to that on the CFT while the opposite trend was found in the Turkish counterpart, suggesting that letter fluency performance was more degraded in Japanese patients. Finally, Analysis 3 was conducted to examine the relative order of letter fluency impairment among Japanese, Turkish and English-speaking patients. Disassociation in English users with schizophrenia was estimated based on previous meta-analytic reviews. The effect size (ES) for the letter fluency deficit was the largest in the Japanese sample, while the other two groups share similar ESs. The results from the three analyses partially supported the hypothesis for the severity of the letter fluency impairment in patients with schizophrenia. The language-dependency of letter fluency impairment was thought to be explained by the theoretical model built on unique properties of sound and writing systems. The considerations presented here would provide useful information for optimizing the portability of cognitive tasks across languages.

Mismatch negativity is a stronger indicator of functional outcomes than neurocognition or theory of mind in patients with schizophrenia

OBJECTIVES

Mismatch negativity (MMN) is known to be associated with neurocognition, social cognition, and functional outcomes. The present study explored the relationships of MMN with neurocognition, theory of mind, and functional outcomes in patients with schizophrenia, first-degree relatives of patients with schizophrenia, and healthy controls.

METHODS

Twenty-five patients with schizophrenia, 21 first-degree relatives of patients with schizophrenia, and 29 healthy controls were recruited. We examined symptom severity, neurocognition, theory of mind, functional outcomes, and MMN.

RESULTS

MMN amplitudes decreased in order of patients with schizophrenia, then first-degree relatives, then healthy controls. MMN amplitude was significantly correlated with measures of neurocognition, theory of mind, and functional outcome measurements in patients with schizophrenia. However, the most powerful correlations were those between MMN in the frontal region and measures of functional outcomes. The power and frequency of the correlations were weaker in first-degree relatives and healthy controls than in patients with schizophrenia. Hierarchical regression analysis revealed that functional outcomes (relative to measures of neurocognition and theory of mind) constituted the most powerful predictor of MMN.

CONCLUSIONS

Our results suggest that MMN reflects functional outcomes more efficiently than do measures of neurocognition and theory of mind in patients with schizophrenia.

Brief assessment of cognition in schizophrenia: normative data in an English-speaking ethnic Chinese sample

There is a dearth of non-Western normative data for neuropsychological batteries designed to measure cognitive deficits in schizophrenia. Here, we provide normative data for English-speaking ethnic Chinese on the widely used Brief Assessment of Cognition in Schizophrenia acquired from 595 healthy community participants between ages 14 and 55. Means and standard deviations of subtests and composite scores were stratified by age group and sex. We also explored linear regression approaches to generate continuous norms adjusted for age, sex, and education. Notable differences in subtest performances were found against a Western comparison sample. Normative data established in the current sample are essential for clinical and research purposes as it serves as a reference source of cognition for ethnic Chinese.

Sensitivity and applicability of the Brazilian version of the Brief Assessment of Cognition in Schizophrenia (BACS)

Cognitive assessment in schizophrenia has traditionally used batteries that are long and complex or differ widely in their content. The Brief Assessment of Cognition in Schizophrenia (BACS) has been developed to cover the main cognitive deficits of schizophrenia as well as to be easily and briefly administered, portable, sensitive and reliable.

Objectives

To investigate the applicability and sensitivity of the Brazilian Version of the BACS (Brazilian-BACS).

Methods

Performance of 20 stable patients with schizophrenia on the Brazilian-BACS was compared to 20 matched healthy controls.

Results

Applying the Brazilian-BACS required 43.4±8.4minutes for patients and 40.5±5.7 minutes for controls (p=0.17). All tests demonstrated significant differences between controls and patients (P<0.01). Pearson's correlation analysis and Cronbach's a evidenced a high internal consistency for patient performance. The cognitive deficit in the patients was approximately 1.5 standard deviations below controls. These results were consistent with those reported in the validation of the original version and in meta-analyses of similar studies.

Conclusions

The Brazilian-BACS displayed good applicability and sensitivity in assessing the major cognitive constructs that are impaired in schizophrenia. Thus, the Brazilian-BACS seems to be a promising tool for assessing cognition in patients with schizophrenia in Brazil.