Meta-analysis of Cognitive Impairment in First-Episode Bipolar Disorder: Comparison With First-Episode Schizophrenia and Healthy Controls

Neurocognitive deficits are evident both in established schizophrenia and bipolar disorder (BP). However, it has been suggested that schizophrenia, but not BP, is characterized by neurodevelopmental abnormalities that can lead to cognitive deficits at the earliest stages of the illness. The aim of this meta-analytic review was to compare neurocognitive deficits in first-episode BP (FEBP) with healthy controls and first-episode schizophrenia (FES) patients. The current meta-analysis included a total of 22 adult studies and involved comparisons of 533 FEBP patients with 1417 healthy controls and 605 FEBP and 822 FES patients. FEBP patients were significantly impaired in all cognitive domains (d = 0.26–0.80) and individual tasks (d = 0.22–0.66) investigated. FES patients significantly underperformed FEBP patients in most cognitive domains (d = 0.05–0.63) and on individual tasks (d = 0.13–0.77). Neuropsychological impairment, which is comparable to chronic BP, was evident in FEBP. Similar to chronic patients, cognitive functions in FEBP lie intermediate between FES and healthy controls. Neurodevelopmental factors are likely to play a significant role not only in schizophrenia but also in BP.Key words: bipolar disorder, cognition/mania, psychosis, schizophrenia     

Developing a Cognitive Training Strategy for First-Episode Schizophrenia: Integrating Bottom-Up and Top-Down Approaches

It is clear that people with schizophrenia typically have cognitive problems in multiple domains as part of their illness. The cognitive deficits are among the main contributors to limitations in their everyday functioning, including their work recovery. Cognitive remediation has been applied successfully to help people with long-term, persistent schizophrenia to improve their cognitive functioning, but it is only beginning to be applied with individuals who have recently had a first episode of psychosis. Several different approaches to cognitive training have been developed. Some approaches emphasize extensive systematic practice with lower-level cognitive processes and building toward higher-level processes (bottom-up), while others emphasize greater focus on high-level cognitive processes that normally integrate and organize lower-level processes (top-down). Each approach has advantages and disadvantages for a disorder like schizophrenia, with its multiple levels of cognitive dysfunction. In addition, approaches to cognitive remediation differ in the extent to which they systematically facilitate transfer of learning to everyday functioning. We describe in this article the cognitive training approach that was developed for a UCLA study of people with a recent first episode of schizophrenia, a group that may benefit greatly from early intervention that focuses on cognition and recovery of work functioning. This approach integrated bottom-up and top-down computerized cognitive training and incorporated an additional weekly group session to bridge between computerized training and application to everyday work and school functioning.     

Interrelationships Between BDNF,Superoxide Dismutase,and Cognitive Impairment in Drug-Naive First-Episode Patients With Schizophrenia

The pathogenesis and etiology of schizophrenia (SCZ) remains unclear. Accumulating studies showed that complex interrelationships between brain-derived neurotrophic factor (BDNF) and an imbalanced redox system has a crucial role in the psychopathology of SCZ. However, the influence of the interrelationships of BDNF and superoxide dismutase (SOD) on cognitive impairment and clinical symptomatology in drug-naive first-episode (DNFE) SCZ patients has not been studied thoroughly. Serum BDNF levels, plasma total SOD, manganese-SOD (Mn-SOD), copper/zinc-containing SOD (CuZn-SOD) activities, and malondialdehyde (MDA) levels were measured in 327 DNFE patients with SCZ and 391 healthy controls. Cognitive functions were measured using the Repeatable Battery for the Assessment of Neuropsychological status (RBANS) and clinical symptoms were evaluated by the Positive and Negative Syndrome Scale (PANSS). Compared with the controls, the DNFE patients had increased activities of total SOD and CuZn-SOD, and reduced levels of BDNF and MDA. BDNF levels were positively correlated with CuZn-SOD activity in patients. In addition, we found that elevated Mn-SOD and CuZn-SOD activities were related to PANSS depression factor. Moreover, an interactive effect of BDNF levels and Mn-SOD activity was associated with attentional index score in the patients. Therefore, our findings suggested that interrelationships between BDNF and antioxidant mechanisms might underlie the pathological mechanisms of cognitive impairments and symptomatology in the DNFE patients with SCZ.     

Cognitive,Work and Social Outcomes in Fully Recovered First-Episode Schizophrenia: On and Off Antipsychotic Medication

Objective: This study examined the development in cognition, work, and social functioning in a group of fully recovered first-episode schizophrenia (FES) patients across six–eight years and inspected whether changes in outcome were similar when individuals were off medication as when they were on medication. Method: Ten out of 28 participants were identified as fully recovered by the eighth follow-up. Assessments were conducted yearly, apart from the first year, when assessments were conducted every six months. Cognition was assessed with MATRICS Consensus Cognitive Battery. Functional outcomes were obtained through Global functioning: Social and Global functioning: Role. Information from semistructured interviews were also gathered. Data were analyzed with linear multilevel models. Results: There were steady improvements in cognition, social, and role functioning among the patients, but the changes were significantly larger when individuals were off antipsychotic medications than on medications for processing speed and work functioning. T-tests showed that unmedicated participants were not healthier than medicated participants at baseline. The most common reason for discontinuing medication treatment was negative side effects. Instead, many of the participants highlighted the use of active coping mechanisms for maintaining recovery. Conclusions: The findings challenge some of the views about medication treatment of FES patients. For a subgroup of FES patients, continuous medication treatment is not necessary for maintaining low levels of symptoms. These patients show sustained good functioning once fully recovered. Due to a small sample size, these results may not be generalized to the general FES population and need to be replicated with studies of larger sample sizes.     

The Effect of Paternal Age on Relapse in First-Episode Schizophrenia

Objective:

Multiple etiological and prognostic factors have been implied in schizophrenia and its outcome. Advanced paternal age has been reported as a risk factor in schizophrenia. Whether this may affect schizophrenia outcome was not previously studied. We hypothesized that advanced paternal age may have a negative effect on the outcome of relapse in schizophrenia.

Method:

We interviewed 191 patients with first-episode schizophrenia and their relatives for parental ages, sociodemographic factors at birth, birth rank, family history of psychotic disorders, and obstetric complications. The outcome measure was the presence of relapse at the end of the first year of treatment.

Results:

In the 1-year follow-up period, 42 (22%) patients experienced 1 or more relapses. The mean paternal age was 34.62 years (SD 7.69). Patients who relapsed had significantly higher paternal age, poorer medication adherence, were female, and were hospitalized at onset, compared with patients who did not relapse. A multivariate regression analysis showed that advanced paternal age (OR 1.05, 95% CI 1.01 to 1.10), medication nonadherence (OR 2.37, 95% CI 1.12 to 4.99), and female sex (OR 2.44, 95% CI 1.14 to 5.24) independently contributed to a higher risk of relapse. Analysis between different paternal age groups found a significantly higher relapse rate with paternal age over 40.

Conclusions:

Advanced paternal age is found to be modestly but significantly related to more relapses, and such an effect is the strongest at a cut-off of paternal age of 40 years or older. The effect is less likely to be mediated through less effective parental supervision or nonadherence to medication. Other possible biological mechanisms need further explorations.     

Antipsychotics Effects on Network-Level Reconfiguration of Cortical Morphometry in First-Episode Schizophrenia

Cortical thickness reductions are evident in schizophrenia (SZ). Associations between antipsychotic medications (APMs) and cortical morphometry have been explored in SZ patients. This raises the question of whether the reconfiguration of morphological architecture by APM plays potential compensatory roles for abnormalities in the cerebral cortex. Structural magnetic resonance imaging was obtained from 127 medication-naive first-episode SZ patients and 133 matched healthy controls. Patients received 12 weeks of APM and were categorized as responders (n = 75) or nonresponders (NRs, n = 52) at follow-up. Using surface-based morphometry and structural covariance (SC) analysis, this study investigated the short-term effects of antipsychotics on cortical thickness and cortico-cortical covariance. Global efficiency was computed to characterize network integration of the large-scale structural connectome. The relationship between covariance and cortical thinning was examined by SC analysis among the top-n regions with thickness reduction. Widespread cortical thickness reductions were observed in pre-APM patients. Post-APM patients showed more reductions in cortical thickness, even in the frontotemporal regions without baseline reductions. Covariance analysis revealed strong cortico-cortical covariance and higher network integration in responders than in NRs. For the NRs, some of the prefrontal and temporal nodes were not covariant between the top-n regions with cortical thickness reduction. Antipsychotic effects are not restricted to a single brain region but rather exhibit a network-level covariance pattern. Neuroimaging connectomics highlights the positive effects of antipsychotics on the reconfiguration of brain architecture, suggesting that abnormalities in regional morphology may be compensated by increasing interregional covariance when symptoms are controlled by antipsychotics.     

Resting-State Brain Activity in Schizophrenia and Major Depression: A Quantitative Meta-Analysis

Intrinsic activity of the brain during resting-state is not random and is currently discussed as a neural reflection of self-referential processing. Self-reference is typically reduced in schizophrenia as a disorder of the self while extensive self-attribution of, eg, negative thoughts is characteristic for major depression. However, a quantitative meta-analysis targeting the resting-state brain activity in both disorders is lacking. Here, we predict primarily abnormal resting-state activity in brain regions related to self-referential processing. By means of activation likelihood estimation (ALE) on functional magnetic resonance imaging and positron emission tomography studies, we investigated concurrence of hyperactivation and hypoactivation in resting-state measurements of schizophrenic and depressed patients compared with healthy controls. We found hypoactivation in ventromedial prefrontal cortex (vmPFC), left hippocampus, posterior cingulate cortex, lower precueus and the precuneus, and hyperactivation in bilateral lingual gyrus of schizophrenic patients. In major depression, we found hyperactivation in vmPFC, left ventral striatum, and left thalamus and hypoactivation in left postcentral gyrus, left fusiform gyrus, and left insula. An overall ALE analysis confirmed the proximity of hypoactivation in schizophrenia and hyperactivation in major depression in the vmPFC.The opposing resting-state activity in vmPFC for the 2 disorders is in line with the different expression of dysfunctional self-reference as core characteristics of schizophrenia and major depression. The vmPFC has previously been identified as a crucial area for self-referential processing and may represent a target to increase the diagnostic validity of resting-state activity for disorders with dysfunctions of the self.     

Dissecting the Heterogeneity of Treatment Response in First-Episode Schizophrenia

The Mental Health Centers for Intervention Development and Applied Research (CIDAR) program prioritized research to provide an evidence base for biomarker development. At the Zucker Hillside Hospital (ZHH), our CIDAR grant supported research on a comprehensive investigation of treatment response and outcome in first episode schizophrenia. Results provide evidence that baseline neuroimaging, neurocognitive, and genetic measures are significantly associated with clinical response to treatment, and that our currently available interventions can effectively treat aspects of psychotic illness, as well as potentially reduce comorbidity associated with illness. Future research may include combining modalities to more robustly predict response and identify treatment targets, as well as to further develop more effective intervention strategies for these devastating and disabling disorders.Key words: schizophrenia, biomarkers, antipsychotic, efficacy, cognitionIn many areas of medicine, heterogeneity of patient outcomes is managed by the availability of multiple therapeutic options, and treatment decisions are guided by clinical biomarkers. Well-known examples in broad clinical use include the HER2 marker for herceptin treatment of breast cancer,¹ and natriuretic peptide levels for diagnosis and prognosis of heart failure.² By contrast, treatment options for patients with schizophrenia are relatively undifferentiated, and clinicians lack objective tools to dissect patient heterogeneity with respect to treatment and prognosis. Development of biomarkers in psychiatry can be critical to both the application of existing treatments and the development of novel treatments.The announcement of the Mental Health Centers for Intervention Development and Applied Research (CIDAR) program in 2005 prioritized research to provide an evidence base for biomarker development. This announcement coincided with an important evolution in research at our institution, the Zucker Hillside Hospital (ZHH). Developments in neuroimaging, neurocognition, and molecular genetics provided the means to broaden our treatment research in first episode schizophrenia to encompass the development of individualized assessment tools to dissect the heterogeneity of treatment response in this important population. The CIDAR program provided the first NIH-funded mechanism to integrate these efforts into a comprehensive investigation of treatment response and outcome in first episode schizophrenia.This theme is focused on the first episode of psychosis, which may be the most critical period in the life of an individual with schizophrenia, and remains the most opportune time for the study of key mechanisms that influence treatment response and outcome of this often chronically disabling disorder. Several factors render the first episode a critical research window: first episode patients are generally young, and therefore within a relatively restricted age range; they have a shorter duration of psychotic symptoms; and less illness-related functional and social impairment related to chronicity of illness. Perhaps most critical is that first episode patients have minimal prior psychopharmacological treatment, reducing medication confounds for research aimed at identifying the neurobiological substrates associated with illness and the prediction of illness course.The ZHH CIDAR (P50MH080173; Dissecting the heterogeneity of treatment response in first episode schizophrenia; PI: Anil K. Malhotra), funded in 2008, integrated therapeutic knowledge and experience with the expertise of investigators utilizing neurocognitive, neuroimaging and molecular genetics approaches to biomarkers development. We focused on the assessment of a cohort of first episode schizophrenia patients participating in a 12-week clinical trial of 2 second generation antipsychotics (SGAs), aripiprazole and risperidone, and a follow-up extension phase of controlled treatment for 1 year. The primary CIDAR assessments were conducted prior to the initiation of treatment and during 12 weeks of double-blind treatment. The CIDAR comprises 3 cores supporting 3 independent projects, with additional NIH and FDA funding to support a supplemental project focused on the reactions of young people with early phase schizophrenia to tobacco smoking warning materials. The major aim of each of the 3 initial projects was to identify predictors of SGA response in this cohort, using neuroimaging, neurocognitive and genetic indices.     

Neurophyisological and Neurocognitive Endophenotypes for Schizophrenia Genetics Research

There is growing interest in the genetic analysis of schizophrenia using endophenotypes rather than clinical diagnosis or symptom dimensions. Endophenotypes could be alternative phenotypes for the clinical phenotypes. With their intermedicate and quantitative characteristics, endophenotypes could be functionally important links in the pathways between the genetic variation and clinical expression of the disorder. In this regard, the neurophysiological and neurocognitive endophenotypes used in the genetic analysis of schizophrenia have been reviewed.     

Impact of Antipsychotic Treatment on Attention and Motor Learning Systems in First-Episode Schizophrenia

Background: Antipsychotic medications have established clinical benefit, but there are few neuroimaging studies before and after initiating antipsychotic medication to assess drug influence on brain circuitry. Attention and motor learning tasks are promising approaches for examining treatment-related changes in frontostriatal systems. Methods: Twenty-one unmedicated first-episode schizophrenia patients (14 antipsychotic-naïve) participated in functional imaging studies while performing visual attention (prosaccades) and motor learning tasks (predictive saccades). Posttreatment testing was completed in 14 patients after 4–6 weeks of antipsychotic treatment. Matched healthy controls were studied in parallel. Results: Pretreatment, patients had reduced activation in the dorsal neocortical visual attention network. Activation deficits were significantly reduced posttreatment. Higher medication dose was associated with greater caudate activation at follow-up. For the motor learning task, patients’ dorsolateral prefrontal cortex (DLPFC) was unimpaired prior to treatment but showed significantly reduced activation after treatment. Conclusion: Impairments in dorsal cortical attention networks are present in untreated first-episode schizophrenia patients. These impairments are reduced after antipsychotic treatment, suggesting a beneficial effect on neural systems for attention. Treatment-emergent decreases in DLPFC activation observed for the motor learning task are consistent with other clinical and preclinical evidence suggesting that antipsychotics can have adverse effects on prefrontal function.Key words: fMRI, cognition, dorsolateral prefrontal cortex, saccades, caudate, risperidone     

Sensitivity and Specificity of Memory Dysfunction in Schizophrenia: A Comparison With Major Depression

Fifty-three schizophrenic subjects were compared to 50 patients with major depression and 50 normal controls on measures of working memory, declarative memory and malingering. The schizophrenic group scored 1–2 SDs below controls on all measures, while depressive patients exposed only lesser deficits in working memory and free recall. The memory deficit of the schizophrenic subjects was disproportionately greater than their intellectual decline. Differences between clinical groups could not be explained by differences in IQ, clinical symptom load or demographic characteristics. This indicates that impaired memory is a particular sensitive symptom of schizophrenia and that the impairment is specific to the illness. Working memory failure was prominent in both clinical groups. The schizophrenic subjects displayed primarily an acquisition failure, while the depressed group showed retrieval difficulties.     

Cognitive Efficacy of Quetiapine and Olanzapine in Early-Onset First-Episode Psychosis

The primary purpose of this study was to compare changes in cognition in early-onset psychosis after 6-months treatment with quetiapine or olanzapine. This is a randomized, single-blind, 6-month study in 50 adolescents with a diagnosis of early-onset psychosis. Patients were randomized to quetiapine (n = 24) or olanzapine (n = 26). A thorough neuropsychological battery was administered at baseline and after 6-month treatment. Out of the total sample included in the study, 32 patients completed at least 6-months treatment with the assigned medication (quetiapine, n = 16; olanzapine, n = 16). No changes were observed in cognitive performance after 6-month treatment with quetiapine or olanzapine. Although some trends toward cognitive improvement were observed for the olanzapine group after 6-month treatment, neither group showed statistically significant gains. Furthermore, there was no evidence of any differential efficacy of olanzapine or quetiapine on cognitive improvement in this sample of adolescents with psychosis.     

Relationship of Cognition to Clinical Response in First-Episode Schizophrenia Spectrum Disorders

First-episode schizophrenia (FES) spectrum disorders are associated with pronounced cognitive dysfunction across all domains. However, less is known about the course of cognitive functioning, following the first presentation of psychosis, and the relationship of cognition to clinical course during initial treatment. The present longitudinal study examined the magnitude of neurocognitive impairment, using the MATRICS Consensus Cognitive Battery, in patients experiencing their first episode of psychosis at baseline and after 12 weeks of randomized antipsychotic treatment with either aripiprazole or risperidone. At baseline, FES patients evidenced marked impairments in cognitive functioning. Notably, performance on the mazes task of planning and reasoning significantly predicted the likelihood of meeting stringent criteria for positive symptom remission during the first 12 weeks of the trial. Performance on indices of general cognitive function, working memory, and verbal learning improved over time, but these improvements were mediated by improvements in both positive and negative symptoms. We did not detect any differential effects of antipsychotic medication assignment (aripiprazole vs risperidone) on cognitive functioning. Our results suggest that a brief paper-and-pencil measure reflecting planning/reasoning abilities may index responsivity to antipsychotic medication. However, improvements in cognitive functioning over time were related to clinical symptom improvement, reflecting “pseudospecificity.”Key words: cognition, general cognitive function, psychosis, planning, aripiprazole, risperidone     

The Impact of Cannabis Use on Cognitive Functioning in Patients With Schizophrenia: A Meta-analysis of Existing Findings and New Data in a First-Episode Sample

Cannabis use is highly prevalent among people with schizophrenia, and coupled with impaired cognition, is thought to heighten the risk of illness onset. However, while heavy cannabis use has been associated with cognitive deficits in long-term users, studies among patients with schizophrenia have been contradictory. This article consists of 2 studies. In Study I, a meta-analysis of 10 studies comprising 572 patients with established schizophrenia (with and without comorbid cannabis use) was conducted. Patients with a history of cannabis use were found to have superior neuropsychological functioning. This finding was largely driven by studies that included patients with a lifetime history of cannabis use rather than current or recent use. In Study II, we examined the neuropsychological performance of 85 patients with first-episode psychosis (FEP) and 43 healthy nonusing controls. Relative to controls, FEP patients with a history of cannabis use (FEP + CANN; n = 59) displayed only selective neuropsychological impairments while those without a history (FEP − CANN; n = 26) displayed generalized deficits. When directly compared, FEP + CANN patients performed better on tests of visual memory, working memory, and executive functioning. Patients with early onset cannabis use had less neuropsychological impairment than patients with later onset use. Together, these findings suggest that patients with schizophrenia or FEP with a history of cannabis use have superior neuropsychological functioning compared with nonusing patients. This association between better cognitive performance and cannabis use in schizophrenia may be driven by a subgroup of “neurocognitively less impaired” patients, who only developed psychosis after a relatively early initiation into cannabis use.