Correlating cognitive functions to symptom domains and insight in Egyptian patients with schizophrenia

Anticholinergic load: A commonly neglected and preventable risk to cognition during schizophrenia treatment?

Background

Cognitive impairment is a widespread feature of schizophrenia, affecting nearly 80 % of patients. Prior research has linked the anticholinergic burden of psychiatric medications to these cognitive deficits. However, the impact of the anticholinergic burden from medications for physical morbidity remains underexplored. This study aimed to evaluate the anticholinergic burden of psychiatric and physical medications in patients with schizophrenia and assess its impact on cognitive function.

Methods

A total of 178 patients with schizophrenia were recruited. The assessments included an ad hoc questionnaire for collecting demographic and clinical data. Anticholinergic burden was evaluated using the cumulative Drug Burden Index (cDBI) for each participant, and cognitive function was assessed using MATRICS. Psychopathology was measured using the PANSS, CDSS, CAINS, and the CGI-S. Statistical analysis included Student's t-tests, ANOVA, Pearson correlations, and multiple linear regressions.

Results

The average cDBI was 1.3 (SD = 0.9). The model developed explained 40.80 % of the variance. The variable with the greatest weight was the cDBI (B = -11.148, p = 0.010). Negative-expression (B = -2.740, p = 0.011) and negative-experiential (B = -1.175, p = 0.030) symptoms were also associated with lower global cognitive score. However, more years of education (B = 5.140, p < 0.001) and cigarettes per day (B = 1.331, p < 0.001) predicted a better global cognitive score.

Conclusion

This study identified specific predictors of global cognition in schizophrenia, with anticholinergic burden emerging as the strongest factor. Our findings underscore the importance of considering the anticholinergic burden of treatments, in addition to negative symptoms, when designing interventions to optimize or maintain cognitive function in patients with schizophrenia.

Cognitive Impairments in Drug-Naive Patients With First-Episode Negative Symptom-Dominant Psychosis

Importance

Available antipsychotic medications are predominantly used to treat positive symptoms, such as hallucinations and delusions, in patients with first-episode psychosis (FEP). However, treating negative and cognitive symptoms, which are closely related to functional outcomes, remains a challenge.

Objective

To explore the cognitive characteristics of patients with negative symptom-dominant (NSD) psychosis.

Design, Setting, and Participants

This large-scale cross-sectional study of patients with FEP was led by the Shanghai Mental Health Center in China from 2016 to 2021, with participants recruited from 10 psychiatric tertiary hospitals. A comprehensive cognitive assessment was performed among 788 patients with FEP who were drug-naive. Symptom profiles were determined using the Positive and Negative Symptoms Scale (PANSS), and NSD was defined as a PANSS score for negative symptoms higher than that for positive and general symptoms. Positive symptom-dominant (PSD) and general symptom-dominant (GSD) psychosis were defined similarly. Data were analyzed in 2023.

Exposure

Psychotic symptoms were categorized into 3 groups: NSD, PSD, and GSD.

Main Outcomes and Measures

Neurocognitive performance, assessed using the Chinese version of the Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery.

Results

This study included 788 individuals with FEP (median age, 22 [IQR, 17-28] years; 399 men [50.6%]). Patients with NSD exhibited more-pronounced cognitive impairment than did those with PSD or GSD. Specifically, cognitive differences between the NSD and PSD group, as well as between the NSD and GSD group, were most notable in the processing speed and attention domains (Trail Making [F = 4.410; P = .01], Symbol Coding [F = 4.957; P = .007], Verbal Learning [F = 3.198; P = .04], and Continuous Performance [F = 3.057; P = .05]). Patients with PSD and GSD showed no significant cognitive differences. Cognitive impairment was positively associated with the severity of negative symptoms. Most of the cognitive function tests used were able to differentiate patients with NSD from those with PSD and GSD, with significant differences observed across a range of tests, from Brief Visuospatial Memory Test-Revised (χ2 = 3.968; P = .05) to Brief Assessment of Cognition in Schizophrenia symbol coding (χ2 = 9.765; P = .002).

Conclusions and Relevance

The findings of this cross-sectional study of patients with FEP suggest the presence of a clinical subtype characterized by a predominance of negative symptoms and cognitive impairment.

Cold executive function processes and their hot analogs in schizotypy

OBJECTIVE

To examine cold (based on logical reasoning) versus hot (having emotional components) executive function processes in groups with high individual schizotypal traits.

METHOD

Two-hundred and forty-seven participants were administered the Schizotypal Personality Questionnaire and were allocated into schizotypal (cognitive-perceptual, paranoid, negative, disorganized) or control groups according to pre-specified criteria. Participants were also administered a battery of tasks examining working memory, complex selective attention, response inhibition, decision-making and fluid intelligence and their affective counterparts. The outcome measures of each task were reduced to one composite variable thus formulating five cold and five hot cognitive domains. Between-group differences in the cognitive domains were examined with repeated measures analyses of covariance.

RESULTS

For working memory, the control and the cognitive-perceptual groups outperformed negative schizotypes, while for affective working memory controls outperformed the disorganized group. Controls also scored higher compared with the disorganized group in complex selective attention, while both the control and the cognitive-perceptual groups outperformed negative schizotypes in complex affective selective attention. Negative schizotypes also had striking difficulties in response inhibition, as they scored lower compared with all other groups. Despite the lack of differences in fluid intelligence, controls scored higher compared with all schizotypal groups (except from cognitive-perceptual schizotypes) in emotional intelligence; the latter group reported higher emotional intelligence compared with negative schizotypes.

CONCLUSION

Results indicate that there is no categorical association between the different schizotypal dimensions with solely cold or hot executive function processes and support impoverished emotional intelligence as a core feature of schizotypy.

Atypical frontotemporal cortical activity in first-episode adolescent-onset schizophrenia during verbal fluency task: A functional near-infrared spectroscopy study

Background

Frontotemporal cortex dysfunction has been found to be associated with cognitive impairment in patients with schizophrenia (SCZ). In patients with adolescent-onset SCZ, a more serious type of SCZ with poorer functional outcome, cognitive impairment appeared to occur at an early stage of the disease. However, the characteristics of frontotemporal cortex involvement in adolescent patients with cognitive impairment are still unclear. In the present study, we aimed to illustrate the frontotemporal hemodynamic response during a cognitive task in adolescents with first-episode SCZ.

Methods

Adolescents with first-episode SCZ who were aged 12-17 and demographically matched healthy controls (HCs) were recruited. We used a 48-channel functional near-infrared spectroscopy (fNIRS) system to record the concentration of oxygenated hemoglobin (oxy-Hb) in the participants' frontotemporal area during a verbal fluency task (VFT) and analyzed its correlation with clinical characteristics.

Results

Data from 36 adolescents with SCZ and 38 HCs were included in the analyses. Significant differences were found between patients with SCZ and HCs in 24 channels, mainly covering the dorsolateral prefrontal cortex, superior and middle temporal gyrus and frontopolar area. Adolescents with SCZ showed no increase of oxy-Hb concentration in most channels, while the VFT performance was comparable between the two groups. In SCZ, the intensity of activation was not associated with the severity of symptoms. Finally, receiver operating characteristic analysis indicated that the changes in oxy-Hb concentration could help distinguish the two groups.

Conclusion

Adolescents with first-episode SCZ showed atypical cortical activity in the frontotemporal area during the VFT, and fNIRS features might be more sensitive indicators in cognitive assessment, indicating that the characteristic hemodynamic response pattern might be potential imaging biomarkers for this population.

An Update on Clinical Insight, Cognitive Insight, and Introspective Accuracy in Schizophrenia-Spectrum Disorders: Symptoms, Cognition, and Treatment

INTRODUCTION

Poor insight, or unawareness of morbid changes in cognition, emotional states, or behavior, is commonly observed among people with schizophrenia. Poor insight represents a persistent barrier to wellness because it interferes with treatment and self-direction. Paradoxically, good insight may also be a barrier to health when awareness of these changes leads to depression or self-stigma.

AREAS COVERED

This paper builds upon this previous work by exploring these issues in schizophrenia separately as they have appeared in published research over the last three years in three different kinds of insight: clinical, cognition, and introspective accuracy. Specifically, studies are reviewed that address: the adverse effects of poor insight, the paradoxical effects of good insight, correlates with other forms of cognition, and emerging treatments.

EXPERT OPINION

The evidence continues to offer a nuanced picture of the complex effects of good insight in schizophrenia. Incremental improvements were also found in the development of novel integrative treatment approaches. This work also highlights the intricacy of the concept of insight, the need for further exploration of the effects of culture, and conceptual work that distinguishes the points of convergence and divergence of these forms of insight.

From Memories of Past Experiences to Present Motivation? A Meta-analysis on the Association Between Episodic Memory and Negative Symptoms in People With Psychosis

Based on findings from cognitive science, it has been theorized that the reductions in motivation and goal-directed behavior in people with psychosis could stem from impaired episodic memory. In the current meta-analysis, we investigated this putative functional link between episodic memory deficits and negative symptoms. We hypothesized that episodic memory deficits in psychosis would be related to negative symptoms in general but would be more strongly related to amotivation than to reduced expressivity. We included 103 eligible studies (13,622 participants) in the analyses. Results revealed significant, moderate negative associations of episodic memory with negative symptoms in general (k = 103; r = -.23; z = -13.40; P ≤ .001; 95% CI [-.26; -.20]), with amotivation (k = 16; r = -.18; z = -6.6; P ≤ .001; 95% CI [-.23; -.13]) and with reduced expressivity (k = 15; r = -.18; z = -3.30; P ≤.001; 95% CI[-.29; -.07]). These associations were not moderated by sociodemographic characteristics, positive symptoms, depression, antipsychotic medication or type of negative symptom scale. Although these findings provide sound evidence for the association between episodic memory deficits and amotivation, the rather small magnitude and the unspecific pattern of this relationship also indicate that episodic memory deficits are unlikely to be the only factor relevant to amotivation. This implicates that future research should investigate episodic memory in conjunction with other factors that could account for the association of episodic memory deficits and amotivation in psychosis.

Consumption of peanut products improves memory and stress response in healthy adults from the ARISTOTLE study: A 6-month randomized controlled trial

BACKGROUND

Peanuts are rich in bioactive compounds that may have a positive impact on memory and stress response.

OBJECTIVE

To evaluate the effect of regular consumption of peanut products on cognitive functions and stress response in healthy young adults.

DESIGN

A three-arm parallel-group randomized controlled trial was conducted in 63 healthy young adults that consumed 25 g/day of skin roasted peanuts (SRP, n = 21), 32 g/d of peanut butter (PB, n = 23) or 32 g/d of a control butter made from peanut oil (free of phenolic compounds and fiber) (CB, n = 19) for six months. Polyphenol intake, cognitive functions, and anxiety and depression scores were evaluated using validated tests. Fecal short-chain fatty acids (SCFAs) and plasma and fecal fatty acids were assessed by chromatographic methods. Urinary cortisol was quantified by an enzymatic method.

RESULTS

Comparing the two interventions with the control, a significant reduction in anxiety scores was observed in the SRP compared to the CB group. After the intervention, consumers of SRP and PB had an improved immediate memory (p = 0.046 and p = 0.011). Lower anxiety scores were associated with SRP and PB (p < 0.001 and p = 0.002, respectively) and lower depression scores with SRP, PB and CB (p = 0.007, p = 0.003 and p = 0.032, respectively). Memory functions and stress response were significantly correlated with polyphenol intake, fecal SCFAs, plasma and fecal very long chain saturated fatty acids (VLCSFAs).

CONCLUSIONS

Regular peanut and peanut butter consumption may enhance memory function and stress response in a healthy young population. These effects seem to be associated with the intake of peanut polyphenols, increased levels of fecal SCFAs, and unexpectedly, VLCSFAs, which were also present in the control product.

Sex differences in association between clinical correlates and cognitive impairment in patients with chronic schizophrenia

Schizophrenia is a heterogeneous disorder with sex differences in clinical manifestations and cognitive function. However, the nature of its sex-specific relationship between clinical manifestations and cognitive impairment remains equivocal. This study aimed to explore the sex differences in the association between cognitive function and clinical features of hospitalized patients with schizophrenia. A total of 251 schizophrenia patients (males/females = 167/84) and 178 healthy controls (males/females = 84/94) were enrolled. Cognitive function was assessed through the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery (MCCB). The Positive and Negative Syndrome Scale (PANSS) was used to evaluate psychiatric symptoms in patients. Both male and female patients performed more impaired than their counterparts on all MCCB tests. However, only the scores of category fluency, attention and reasoning/problem solving of female patients were significantly lower than those of male patients. Multivariate regression analyses demonstrated that attention was independently associated with negative symptoms in female patients, and general psychopathology in male patients. Negative symptoms were also independently associated with verbal learning and memory and social cognition only in male patients, while general psychopathology was independently associated with symbol coding only in female patients. Our results suggest that there are noticeable sex differences in clinical features, cognitive impairment and their associations in schizophrenia patients. These sex-specific associations may provide useful information for future studies aimed at predicting and interfering with the outcome of schizophrenia from a sex perspective.

One-day tropisetron treatment improves cognitive deficits and P50 inhibition deficits in schizophrenia

The core features of schizophrenia (SCZ) include cognitive deficits and impaired sensory gating represented by P50 inhibition deficits, which appear to be related to the α7 nicotinic acetylcholine receptor (nAChR). An agonist of nAChR receptor may improve these defects. This study aimed to investigate how administering multiple doses of tropisetron, a partial agonist of nAChR, for 1 day would affect cognitive deficits and P50 inhibition deficits in SCZ patients. We randomized 40 SCZ non-smokers into a double-blind clinical trial with four groups: placebo, 5 mg/d, 10 mg/d, and 20 mg/d of oral tropisetron. Their P50 ratios were all more than 0.5 and they took risperidone at 3-6 mg/day for at least a month before participating in the experiment. We measured the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and P50 inhibition before and one day after treatment. After one day of treatment, the total RBANS scores of the 20 mg and 5 mg tropisetron groups, and the immediate memory of the 10 mg group were significantly higher than placebo group. The P50 ratio was smaller in the 5 mg and 10 mg groups than in the placebo group (both p < 0.05) after treatment. Furthermore, the improvement in RBANS total score was correlated with increased S1 latency (p < 0.05), and the increase in immediate memory score was correlated with decreased S2 amplitude. One day of treatment with tropisetron improved both cognitive and P50 inhibition deficits, suggesting that longer term treatment with α7 nAChR agonists for these deficits in SCZ may be promising.