A longitudinal study of cognitive functioning in schizophrenia: clinical and biological predictors

Association between the HHEX polymorphism and delayed memory in first-episode schizophrenic patients

The hematopoietically-expressed homeobox gene (HHEX) played a critical role in regulating the immune system that the abnormality of which was involved in the psychopathology and cognitive deficits of psychiatric disorders. The aim of this study was to investigate the effect of HHEX rs1111875 polymorphism on the susceptibility and cognitive deficits of first-episode schizophrenic patients (FSP). We assessed cognitive function in 239 first-episode patients meeting DSM-IV for schizophrenia, and 368 healthy controls using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). The HHEX rs1111875 polymorphism was genotyped. Our results showed that the allelic and genotypic frequencies of HHEX rs1111875 polymorphism didn't differ between FSP and healthy controls (both p > 0.05) after adjusting for sex and age. Cognitive test scores in FSP were significantly lower than those in healthy controls on all scales (all p < 0.001) except for the visuospatial/constructional score (p > 0.05) after adjusting for covariates. There was a significant genotype (p < 0.05) rather than genotype × diagnosis (p > 0.05) effect on the delayed memory score after adjusting for covariates. The HHEX rs1111875 polymorphism was significantly associated with the delayed memory score in FSP (p < 0.05), but not in healthy controls (p > 0.05) after adjusting for covariates. Our findings supported that the HHEX rs1111875 polymorphism did not contribute to the susceptibility to FSP. However, this polymorphism might influence the delayed memory in FSP. Moreover, FSP had poorer cognitive function than healthy controls except for the visuospatial/constructional domain.

Association Between Use of Sodium-Glucose Co-Transporter-2 (SGLT2) Inhibitors and Cognitive Function in a Longitudinal Study of Patients with Type 2 Diabetes

BACKGROUND

The association between sodium-glucose cotransporter-2 inhibitors (SGLT2i) use and cognitive function in type 2 diabetes remains unclear.

OBJECTIVE

Explore the association between SGLT2i and longitudinal changes in cognitive function in adults with type 2 diabetes (T2DM) and assessed the cognitive domains which were impacted by SGLT2i.

METHODS

We conducted a prospective cohort study of 476 patients aged 60.6±7.4 years with follow-up period up to 6.4 years. Data on SGLT2i use was derived from questionnaire and verified with clinical database. We used Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) to assess cognition. The association between SGLT2i use and rate of RBANS score change was examined using multiple linear regression.

RESULTS

There were 138 patients (29.0%) on SGLT2i, including 84 (17.7%) for <  3 years and 54 (11.3%) for ≥3 years. SGLT2i use was positively associated with RBANS total score increase in language (coefficient 0.60; 95% CI 0.10-1.11; p = 0.019) in unadjusted analysis. This positive association persisted in fully adjusted model (coefficient 0.74; 95% CI 0.12 to 1.36; p = 0.019). SGLT2i use for ≥3 years was positively associated with RBANS score increase globally and in language domain in fully adjusted analysis with coefficients 0.54 (95% CI 0.13 to 0.95; p = 0.010) and 1.12 (95% CI 0.27 to 1.97; p = 0.010) respectively.

CONCLUSION

Our findings revealed a previously unobserved association between ≥3 years SGLT2i use and improved cognitive scores globally and in language domain and executive function. Future studies should investigate the role of SGLT2i in ameliorating cognitive decline.

The oropharyngeal microbiome is altered in individuals with schizophrenia and mania

It is being increasingly recognized that human mucosal surfaces are not sterile but are colonized with microorganisms collectively known as the microbiome. The microbiome can alter brain functioning in humans and animals by way of a series of interactions operative in the brain-immune-gut interactome. We characterized the oropharyngeal microbiome in 316 individuals, including 121 with schizophrenia, 62 with mania, 48 with major depressive disorder, and 85 controls without a psychiatric disorder. We found that the oropharyngeal microflora of individuals with schizophrenia and individuals with mania differed from controls in composition and abundance as measured by the weighted UniFrac distance (both p < .003 adjusted for covariates and multiple comparisons). This measure in individuals with major depressive disorder did not differ from that of controls. We also identified five bacterial taxa which differed among the diagnostic groups. Three of the taxa, Neisseria subflava, Weeksellaceae, and Prevotella, were decreased in individuals with schizophrenia or mania as compared to controls, while Streptococci was increased in these groups. One taxa, Schlegelella, was only found in individuals with mania. Neisseria subflava was also positively associated with cognitive functioning as measured by the Repeatable Battery for the Assessment of Neuropsychological Status. There were no taxa significantly altered in individuals with major depression. Individuals with schizophrenia and mania have altered compositions of the oropharyngeal microbiome. An understanding of the biology of the microbiome and its effect on the brain might lead to new insights into the pathogenesis, and ultimately, the prevention and treatment of these disorders.

C-Reactive Protein as a Possible Predictor of Trail-Making Performance in Individuals with Psychiatric Disorders

Cognitive dysfunction is a prominent feature of psychiatric disorders. Studies have shown that systemic low-grade inflammation is crucial in the development of cognitive deficits across psychiatric disorders. The aim of this study was to further examine the role of inflammation and inflammatory mediators in cognitive function in psychiatric disorders. This study included 364 inpatients (53% females) with International Classification of Diseases (ICD)-10 F3 (affective disorders) and F4 (neurotic, stress-related, and somatoform disorders) diagnoses. The mean age was 52 years (22 to 69 years) and the median body mass index was 27.6. Cognitive function was assessed with the Color–Word Interference Test after Stroop and the Trail-Making Test A/B. Multiple linear regression models were calculated to assess the predictive value of C-reactive protein and the kynurenine/tryptophan ratio on cognitive function controlling for age, sex, education, premorbid verbal intelligence quotient, illness duration, depressive symptoms, and obesity-related parameters (e.g., body mass index, high-density lipoprotein). Our data confirm that in patients with psychiatric disorders, C-reactive protein serum concentration is a relevant and important predictor of Trail-Making Test B performance, measuring cognitive flexibility. The effect size of this association did not change much after adding clinical and metabolic variables into the regression model. The kynurenine/tryptophan ratio was not related to cognitive test scores. The involvement of C-reactive protein as a peripheral inflammatory marker in cognitive flexibility and psychomotor processing speed in psychiatric illness can be concluded.

Effects of the number of hospitalizations on cognitive function in Japanese patients with stable schizophrenia

BACKGROUND

The present study aimed to determine whether the number of hospitalizations in schizophrenia patients is associated with reduced cognitive performance, which may in turn imply that recurrences indirectly lead to a worsening in the disorder's progression.

METHODS

Cognitive performance in stable schizophrenia patients was assessed using the Brief Assessment of Cognition in Schizophrenia, Japanese-language version, on 30 patients who had not experienced any hospitalizations (G0), 57 patients who had experienced only one hospitalization (G1), 47 patients with two hospitalizations (G2), and 59 patients with three or more hospitalizations (G3).

RESULTS

Significant differences in motor function and attention and processing speed were found between patients with G0 and those with G1. Significant differences in working memory and verbal fluency were found between patients with G1 and those with G2. Patients with G3 performed even more poorly in comparison with those with G1, showing deficits in verbal memory, working memory, executive function, and composite score. The patients with G3 displayed a greater range of impairment and demonstrated deficits in executive function compared with patients with G2. Finally, G2 and G3 performed more poorly than G0, with deficits in the various cognitive areas.

CONCLUSION

The number of hospitalizations predicted cognitive performance, which suggests that relapse or recurrence may have a long-term neuropsychological impact. Prospective follow-up studies must be completed to explore this effect further because better treatment adherence may have a protective effect on neurocognitive function.

The association between exposure to herpes simplex virus type 1 (HSV-1) and cognitive functioning in schizophrenia: A meta-analysis

Cognitive deficits are characteristic of schizophrenia but their etiology is not understood. Previous studies show an association between viral exposures and cognitive impairment. This meta-analysis was undertaken to determine the relationship of herpes simplex virus type 1 (HSV-1) exposure and cognitive functioning in schizophrenia. A systematic search was performed for studies comparing the cognitive functioning of HSV-1 seropositive vs. seronegative persons with schizophrenia. The primary outcome was the standardized mean difference (SMD) in composite cognitive score using Hedges' g. Secondary outcomes were SMDs in 9cognitive domains. Study heterogeneity was estimated using the I² index and formal tests of heterogeneity using Cochran's Q. In a sample of 3516 individuals from 9 studies the SMD was negative for the composite score and all 9 domains indicating a significant deficit for seropositive individuals in 8 domains. The SMDs ranged from -0.11 (Working Memory) to -0.36 (Visual Spatial). Cochran's Q test indicated heterogeneity for one domain. The I² index of heterogeneity was in the low -moderate range for all but one domain. Exposure to HSV-1 is associated with decreased cognitive functioning in schizophrenia. An increased understanding of HSV-1 exposure might lead to improved methods for the prevention and treatment of cognitive deficits in schizophrenia.

Neurocognitive functioning in patients with first-episode schizophrenia: results of a prospective 15-year follow-up study

To evaluate the course of neuropsychological impairment, patients with first-episode schizophrenia and healthy controls were assessed with a comprehensive test battery at the time of index treatment and after a 5- and 15-year follow-up period. Summary scores for verbal intelligence (VBI), spatial organization, verbal fluency, verbal learning, semantic memory, visual memory, delay/retention rate, short-term memory, visual-motor processing and attention (VSM) and abstraction/flexibility were constructed. Our results show that neurocognitive functioning is impaired already at the onset of schizophrenia and remains stable over the 15-year follow-up period with an improvement in VBI. With regard to the presence of a deficit syndrome, it became apparent that the group with a deficit syndrome showed a deterioration of neurocognitive functions during the follow-up period, most pronounced in VSM. On the other hand, the group without a deficit syndrome showed an improvement in neurocognitive functions at the 15-year follow-up, which exceeded the learning effects of healthy control subjects. Neurocognitive performance at index assessment strongly predicted the performance at the 15-year follow-up. Most likely due to the small sample size, there were only weak associations between treatment with different types of neuroleptics and neurocognitive performance.

Suicide attempts in Chinese Han patients with schizophrenia: cognitive, demographic, and clinical variables

OBJECTIVE

The purpose of this study was to investigate the lifetime suicide attempt rate, clinical characteristics and cognitive function of Chinese patients with chronic schizophrenia who had attempted suicide.

METHODS

We collected data from 908 schizophrenia inpatients about suicide attempts through interviews with the patients and their families, as well as through medical records. All patients were assessed with the Positive and Negative Syndrome Scale, the Rating Scale for Extrapyramidal Side Effects, the Abnormal Involuntary Movement Scale, and the Repeated Battery for the Assessment of Neuropsychological Status.

RESULTS

Of this sample, 97 (10.68%) had attempted suicide. Patients who had attempted suicide were younger, had longer illness duration, and more severe general psychopathology and depressive symptoms than those who had not. Logistic regression analysis confirmed that suicide attempts were correlated with age, smoking, and depression. No cognitive performance differences were observed between patients who had and had not attempted suicide.

CONCLUSIONS

In China, patients with chronic schizophrenia may have a higher prevalence of lifetime suicide attempts than the general population. Some demographic and clinical variables were related to suicide attempts in patients with chronic schizophrenia.

Assessment of cognitive impairment in HSV-1 positive schizophrenia and bipolar patients: Systematic review and meta-analysis

A common characteristic among schizophrenia and bipolar disorder patients is cognitive dysfunction, especially for memory and attention. Recent evidence has suggested that cognitive impairment in schizophrenia and bipolar disorder patients could be associated with herpes simplex virus 1 (HSV-1) infection, due to the ability of HSV-1 to infect neurons in the temporal lobe, which plays a key role in the formation of memory and processing of sensory input. The objective of this review is to analyze the aggregate neuropsychological testing data from previous studies regarding the impact of HSV-1 infection on cognitive function in schizophrenia and bipolar disorder. A systematic literature search generated a total of 379 articles; 12 full-text case control and cross-sectional studies met the eligibility criteria to be included in the review. Pooled effects assessed the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) total scores and the three index scores for immediate memory, delayed memory, and attention in a random effects model. The overall effect for RBANS total score was in favor of the HSV-1 positive group (z = 3.10, p = 0.002). A statistically significant overall effect of cognitive impairment for memory and attention indices was in favor of HSV positive schizophrenia patients (z = 5.95 p < 0.00001). The findings from the meta-analysis suggest that serological evidence of HSV-1 infection has a significant impact on cognitive function with small to moderate effect sizes (-0.23 to -0.49), particularly affecting memory and attention, in schizophrenia and bipolar patients.

Associations between C-reactive protein levels and cognition during the first 6 months after acute psychosis

OBJECTIVE

Inverse relationships between the C-reactive protein (CRP) levels and cognitive performance in acute psychosis have been demonstrated. We aimed to investigate how the serum level and initial change of CRP in acutely admitted patients with psychosis was correlated with cognitive performance during a 6-months follow-up period.

METHODS

The study is part of a pragmatic, randomised trial comparing four different second-generation antipsychotic drugs, and consists of 208 acute phase patients recruited at admittance for psychosis. This study reports data for all groups collectively, and does not compare treatment groups. Measurements of CRP and cognitive performance were conducted at baseline (T1) and after 4 weeks on average after inclusion (T2). Cognition was also assessed after 3 months (T3) and 6 months (T4) of follow-up.

RESULTS

Global cognition improved during the follow-up period of 6 months, especially in the T1-T2 interval. The different cognitive subdomains showed different time-dependent profiles of improvement, with memory and attention improving significantly also in the later phases. Reduction of the CRP level during the initial follow-up interval (T1-T2) was associated with increased overall cognitive performance in the T2-T4 interval, but not in the T1-T2 interval. For the cognitive subdomains, we found an inverse association between change in CRP level and verbal abilities (T2-T4 interval), and attention (T2-T3 interval).

CONCLUSION

These findings indicate that initial changes in the serum level of CRP in the acute phase of psychosis may predict cognitive function in later phases of the disease.

Familial aggregation of MATRICS Consensus Cognitive Battery scores in a large sample of outpatients with schizophrenia and their unaffected relatives

BACKGROUND

The increased use of the MATRICS Consensus Cognitive Battery (MCCB) to investigate cognitive dysfunctions in schizophrenia fostered interest in its sensitivity in the context of family studies. As various measures of the same cognitive domains may have different power to distinguish between unaffected relatives of patients and controls, the relative sensitivity of MCCB tests for relative-control differences has to be established. We compared MCCB scores of 852 outpatients with schizophrenia (SCZ) with those of 342 unaffected relatives (REL) and a normative Italian sample of 774 healthy subjects (HCS). We examined familial aggregation of cognitive impairment by investigating within-family prediction of MCCB scores based on probands' scores.

METHODS

Multivariate analysis of variance was used to analyze group differences in adjusted MCCB scores. Weighted least-squares analysis was used to investigate whether probands' MCCB scores predicted REL neurocognitive performance.

RESULTS

SCZ were significantly impaired on all MCCB domains. REL had intermediate scores between SCZ and HCS, showing a similar pattern of impairment, except for social cognition. Proband's scores significantly predicted REL MCCB scores on all domains except for visual learning.

CONCLUSIONS

In a large sample of stable patients with schizophrenia, living in the community, and in their unaffected relatives, MCCB demonstrated sensitivity to cognitive deficits in both groups. Our findings of significant within-family prediction of MCCB scores might reflect disease-related genetic or environmental factors.

Cytokines and C-reactive protein alterations with respect to cognitive impairment in schizophrenia and bipolar disorder: A systematic review

BACKGROUND

The aim of this article was to perform a systematic review of studies investigating the association between peripheral levels of cytokines and C-reactive protein (CRP), cytokine gene polymorphisms and cognition in patients with schizophrenia and bipolar disorder (BD).

METHODS

The following databases: PubMed, CINAHL Complete, Academic Search Complete, ERIC and Health Source: Nursing/Academic Edition databases were searched according to the PRISMA guidelines. We included studies that investigated the association between peripheral levels of CRP and cytokines, cytokine gene polymorphisms and cognitive performance in schizophrenia and/or BD patients. Subsequently, quality assessment of eligible publications was performed. Results were synthesized by discussing main findings around correlations between inflammatory markers and cognition.

RESULTS

Most consistent results indicate worse cognitive performance in schizophrenia patients with higher CRP levels. Less consistent evidence suggests better cognitive functioning of schizophrenia patients with higher levels of tumour necrosis factor-α (TNF-α). Evidence for the involvement of other cytokines in cognitive impairment in patients with schizophrenia is less convincing due to discordant results or scarcity of studies. Due to low number of studies, it is difficult to draw conclusions on the involvement of CRP and cytokine alterations in the development of cognitive deficits in BD. Single studies suggest the role of CRP, interleukin(IL)-1 receptor antagonist, IL-6 and TNF-α with its receptors in the development of cognitive impairment in BD.

CONCLUSIONS

Peripheral inflammation might be related to cognitive deficits in schizophrenia and BD. Unequivocal conclusions cannot be made due to methodological heterogeneity and low number of studies investigating particular cytokines.

Evidence of increased exposure to Toxoplasma gondii in individuals with recent onset psychosis but not with established schizophrenia

A possible role for Toxoplasma gondii in the etiopathogenesis of schizophrenia is supported by epidemiological studies and animal models of infection. However, recent studies attempting to link Toxoplasma to schizophrenia have yielded mixed results. We performed a nested case-control study measured serological evidence of exposure to Toxoplasma gondii in a cohort of 2052 individuals. Within this cohort, a total of 1481 individuals had a psychiatric disorder and 571 of were controls without a psychiatric disorder. We found an increased odds of Toxoplasma exposure in individuals with a recent onset of psychosis (OR 2.44, 95% Confidence Interval 1.4–4.4, p < .003). On the other hand, an increased odds of Toxoplasma exposure was not found in individuals with schizophrenia or other psychiatric disorder who did not have a recent onset of psychosis. By identifying the timing of evaluation as a variable, these findings resolve discrepancies in previous studies and suggest a temporal relationship between Toxoplasma exposure and disease onset.

The protozoan parasite Toxoplasma gondii has been previously associated with an increased risk of serious psychiatric disorders such as schizophrenia. However, this association has been found in some studies and not others. We examined whether the differences among previous studies might be explained by the timing of patient evaluation and testing. We found that individuals who were evaluated soon after the onset of psychosis had increased odds of exposure to Toxoplasma gondii as evidenced by the measurement of antibodies in their blood. However. we did not find an increased rate of exposure to Toxoplasma gondii in individuals who had a diagnosis of schizophrenia or bipolar disorder but who did not have recent onset psychosis. Our findings are consistent with Toxoplasma exposure occurring around the time of onset of psychiatric symptoms in individuals with schizophrenia. Our findings might lead to the evaluation of new methods for the early treatment of schizophrenia in some individuals.

A new generation computerised metacognitive cognitive remediation programme for schizophrenia (CIRCuiTS): a randomised controlled trial

BACKGROUND

Cognitive remediation (CR) is a psychological therapy, which improves cognitive and social functioning in people with schizophrenia. It is now being implemented within routine clinical services and mechanisms of change are being explored. We designed a new generation computerised CR programme, CIRCuiTS (Computerised Interactive Remediation of Cognition - a Training for Schizophrenia), to enhance strategic and metacognitive processing, with an integrated focus on the transfer of cognitive skills to daily living. This large trial tested its feasibility to be delivered in therapist-led and independent sessions, and its efficacy for improved cognitive and social functioning.

METHODS

A two arm single blind randomised superiority trial comparing CIRCuiTS plus treatment-as-usual (TAU) with TAU alone in 93 people with a diagnosis of schizophrenia. Cognitive, social functioning and symptom outcomes were assessed at pre- and post-therapy and 3 months later.

RESULTS

85% adhered to CIRCuiTS, completing a median of 28 sessions. There were significant improvements in visual memory at post-treatment (p = 0.009) and follow-up (p = 0.001), and a trend for improvements in executive function at post-treatment (p = 0.056) in favour of the CIRCuiTS group. Community function was also differentially and significantly improved in the CIRCuiTS group at post-treatment (p = 0.003) but not follow-up, and was specifically predicted by improved executive functions.

CONCLUSIONS

CIRCuiTS was beneficial for improving memory and social functioning. Improved executive functioning emerges as a consistent predictor of functional gains and should be considered an important CR target to achieve functional change. A larger-scale effectiveness trial of CIRCuiTS is now indicated.

Association of cognitive function and liability to addiction with childhood herpesvirus infections: A prospective cohort study

Liability to substance use disorder (SUD) is largely nonspecific to particular drugs and is related to behavior dysregulation, including reduced cognitive control. Recent data suggest that cognitive mechanisms may be influenced by exposure to neurotropic infections, such as human herpesviruses. In this study, serological evidence of exposure to human herpesvirus Herpes simplex virus Type 1 (HSV-1), cytomegalovirus (CMV), and Epstein-Barr virus (EBV) as well as Toxoplasma gondii was determined in childhood (age ~11 years) in 395 sons and 174 daughters of fathers with or without SUD. Its relationships with a cognitive characteristic (IQ) in childhood and with risk for SUD in adulthood were examined using correlation, regression, survival, and path analyses. Exposure to HSV-1, EBV, and T. gondii in males and females, and CMV in males, was associated with lower IQ. Independent of that relationship, EBV in females and possibly in males, and CMV and possibly HSV-1 in females were associated with elevated risk for SUD. Therefore, childhood neurotropic infections may influence cognitive development and risk for behavior disorders such as SUD. The results may point to new avenues for alleviating cognitive impairment and SUD risk.

Association between DBH 19bp insertion/deletion polymorphism and cognition in schizophrenia with and without tardive dyskinesia

Long-term antipsychotic treatment for schizophrenia is associated with the development of tardive dyskinesia (TD), which is involved in increased cognitive impairment. Dopamine beta-hydroxylase (DBH) gene associated with dopamine and norepinephrine systems influences cognition. Schizophrenia with TD have higher DBH activity than those without TD. This study examined whether DBH5'-insertion/deletion (-Ins/Del) polymorphism could influence cognitive function in schizophrenia with and without TD. The presence of DBH5'-Ins/Del polymorphism was determined in 345 schizophrenia with TD and 397 schizophrenia without TD. The Abnormal Involuntary Movement Scale and Repeatable Battery for Assessment of Neuropsychological Status (RBANS) were used to assess TD severity and cognition. The allele and genotype frequencies of DBH5'-Ins/Del polymorphism did not differ between patients with and without TD (both p>0.05). RBANS total score and subscales did not differ by DBH5'-Ins/Del genotype groups in patients with TD (all p>0.05). However, attention score significantly differed by DBH5'-Ins/Del genotype groups in those without TD (p<0.05). Patients without TD who were Del homozygous had significantly lower attention score than those without TD who were Ins alleles (p<0.05). Immediate memory and attention scores were lower in patients with TD than without TD (both p<0.05). This study indicated that DBH5'-Ins/Del polymorphism may not play a role in the susceptibility to TD and cognitive deficits in schizophrenia with TD, but it may influence cognitive function in schizophrenia with non-TD. Moreover, schizophrenia with TD experienced greater cognitive deficits than those with non-TD, especially in immediate memory and attention.

EPICOG-SCH: A brief battery to screen cognitive impact of schizophrenia in stable outpatients

Brief batteries in schizophrenia, are needed to screen for the cognitive impact of schizophrenia. We aimed to validate and co-norm the Epidemiological Study of Cognitive Impairment in Schizophrenia (EPICOG-SCH) derived brief cognitive battery. A cross-sectional outpatient evaluation was conducted of six-hundred-seventy-two patients recruited from 234 centers. The brief battery included well-known subtests available worldwide that cover cognitive domains related to functional outcomes: WAIS-III-Letter-Number-Sequencing-LNS, Category Fluency Test-CFT, Logical-Memory Immediate Recall-LM, and Digit-Symbol-Coding-DSC. CGI-SCH Severity and WHO-DAS-S were used to assess clinical severity and functional impairment, respectively. Unit Composite Score (UCS) and functional regression-weighted Composite Scores (FWCS) were obtained; discriminant properties of FWCS to identify patients with different levels of functional disability were analyzed using receiver-operating characteristic (ROC) technique. The battery showed good internal consistency, Cronbach's alpha = 0.78. The differences between cognitive performance across CGI-SCH severity level subscales ranged from 0.5 to 1 SD. Discriminant capacity of the battery in identifying patients with up to moderate disability levels showed fair discriminant accuracy with areas under the curve (AUC) > 0.70, p < 0.0001. An FWCS mean cut-off score ≥ 100 showed likelihood ratios (LR) up to 4.7, with an LR + of 2.3 and a LR - of 0.5. An FWCS cut-off ≥ 96 provided the best balance between sensitivity (0.74) and specificity (0.62). The EPICOG-SCH proved to be a useful brief tool to screen for the cognitive impact of schizophrenia, and its regression-weighted Composite Score was an efficient complement to clinical interviews for confirming patients' potential functional outcomes and can be useful for monitoring cognition during routine outpatient follow-up visits.

Predictors and longitudinal course of cognitive functioning in schizophrenia spectrum disorders, 10years after baseline: The OPUS study

BACKGROUND

Identifying baseline predictors of the long-term course of cognitive functioning in schizophrenia spectrum disorders is important because of associations between cognitive functioning (CF) and functional outcome. Determining whether CF remains stable or change during the course of illness is another matter of interest.

METHODS

Participants from The Danish OPUS Trial, aged 18-45years, with a baseline ICD-10 schizophrenia spectrum diagnosis, were assessed on psychopathology, social and vocational functioning at baseline, and cognitive functioning 5 (N=298) and 10years (N=322) after baseline. Uni- and multi-variable regression analyses of potential baseline predictors of 10-year CF were performed. Also, changes in CF and symptomatology between 5 and 10years of follow-up were assessed.

FINDINGS

Baseline predictors of impaired CF after 10years included male gender, unemployment, poor premorbid achievement and later age of onset. Having finished high school and receiving early intervention treatment was associated with better CF. Age, growing up with both parents, number of family and friends, primary caregivers education, premorbid social function, negative symptoms, GAF (symptoms, function) and substance abuse, were associated with CF in univariable analyses. Non-participants generally suffered from more severe dysfunction. Longitudinally, amelioration in negative symptoms was associated with improved speed of processing and executive functions. Symptom scores generally improved with time, while scores for all cognitive tests remained stable.

CONCLUSION

The current study identifies several robust associations between baseline characteristics and 10-year cognitive outcome. Several other variables were univariably associated with 10-year cognitive outcome. Also, we found evidence for stability of CF over time.

Neuropsychological and neuroimaging underpinnings of schizoaffective disorder: a systematic review

OBJECTIVES

The neurobiological basis and nosological status of schizoaffective disorder remains elusive and controversial. This study provides a systematic review of neurocognitive and neuroimaging findings in the disorder.

METHODS

A comprehensive literature search was conducted via PubMed, ScienceDirect, Scopus and Web of Knowledge (from 1949 to 31st March 2015) using the keyword 'schizoaffective disorder' and any of the following terms: 'neuropsychology', 'cognition', 'structural neuroimaging', 'functional neuroimaging', 'multimodal', 'DTI' and 'VBM'. Only studies that explicitly examined a well defined sample, or subsample, of patients with schizoaffective disorder were included.

RESULTS

Twenty-two of 43 neuropsychological and 19 of 51 neuroimaging articles fulfilled inclusion criteria. We found a general trend towards schizophrenia and schizoaffective disorder being related to worse cognitive performance than bipolar disorder. Grey matter volume loss in schizoaffective disorder is also more comparable to schizophrenia than to bipolar disorder which seems consistent across further neuroimaging techniques.

CONCLUSIONS

Neurocognitive and neuroimaging abnormalities in schizoaffective disorder resemble more schizophrenia than bipolar disorder. This is suggestive for schizoaffective disorder being a subtype of schizophrenia or being part of the continuum spectrum model of psychosis, with schizoaffective disorder being more skewed towards schizophrenia than bipolar disorder.

Neurocognition and Duration of Psychosis: A 10-year Follow-up of First-Episode Patients

A substantial proportion of schizophrenia-spectrum patients exhibit a cognitive impairment at illness onset. However, the long-term course of neurocognition and a possible neurotoxic effect of time spent in active psychosis, is a topic of controversy. Furthermore, it is of importance to find out what predicts the long-term course of neurocognition. Duration of untreated psychosis (DUP), accumulated time in psychosis the first year after start of treatment, relapse rates and symptoms are potential predictors of the long-term course. In this study, 261 first-episode psychosis patients were assessed neuropsychologically on one or more occasions. Patients were tested after remission of psychotic symptoms and reassessed 1, 2, 5, and 10 years after inclusion. The neurocognitive battery consisted of California Verbal Learning Test, Wisconsin Card Sorting Test, Controlled Oral Word Association Task, Trail Making A and B, and Finger Tapping. We calculated a composite score by adding the z-scores of 4 tests that were only moderately inter-correlated, not including Finger Tapping. Data were analyzed by a linear mixed model. The composite score was stable over 10 years. No significant relationship between psychosis before (DUP) or after start of treatment and the composite score was found, providing no support for the neurotoxicity hypothesis, and indicating that psychosis before start of treatment has no significant impact on the course and outcome in psychosis. We found no association between symptoms and the neurocognitive trajectory. Stable remission during the first year predicted neurocognitive functioning, suggesting that the early clinical course is a good predictor for the long-term course.