Cognitive markers of psychotic unipolar depression: a meta-analytic study

Psychotic symptoms in Chinese adolescent patients with major depressive disorder: prevalence and related endocrine clinical factors

OBJECTIVE

Major depressive disorder (MDD) is often accompanied by psychotic symptoms. However, few studies have examined the relationship between psychotic symptoms and endocrine factors in adolescent patients with MDD. Therefore, this study aimed to investigate the prevalence and related endocrine clinical factors of psychotic symptoms in Chinese adolescent patients with MDD.

METHODS

In total, 601 patients (aged 12-18) with MDD were recruited. The Patient Health Questionnaire - 9 items (PHQ - 9) was utilized for assessing depressive symptoms. Psychotic symptoms were assessed through clinical interviews. Prolactin (PRL), thyroid-stimulating hormone (TSH), triiodothyronine (T3), free triiodothyronine (FT3), thyroxine (T4), and free thyroxine (FT4) were also measured.

RESULTS

The incidence of psychotic symptoms in adolescent patients with MDD was 22.6%. The findings demonstrated that age, self-harming behavior, PHQ-9 score, FT4, and normalized PRL were independently associated with psychotic symptoms in patients with MDD (All p < 0.05).

CONCLUSIONS

PRL and FT4 levels are more likely to be abnormally elevated in major depressive adolescents with psychotic symptoms. Prolactin and thyroid hormones in patients with MDD should be paid more attention.

Prevalence and clinical correlates of psychotic symptoms in first-episode untreated female chinese patients with major depressive disorder

BACKGROUND

Recent studies have reported that psychotic symptoms are common in patients with major depressive disorder (MDD). However, few studies have reported the relationship between thyroid function, lipid metabolism and clinical profiles in female MDD patients. Thus, this study aimed to investigate the prevalence of psychotic depression (PD) and its risk factors in first-episode and drug naive (FEDN) depression among the female population in China.

METHODS

This was a cross-sectional study involving a representative probability sample of 1,130 FEDN female outpatients with MDD (aged 18 years or older) in China. We collected information relating to socio-demographic characteristics, clinical data and blood samples. The Hamilton Depression Rating Scale 17-item version (HAMD-17), Hamilton Anxiety Rating Scale 14-item version (HAMA-14), and Positive and Negative Syndrome Scale (PANSS) were used to evaluate depressive, anxiety, and psychotic symptoms.

RESULTS

The prevalence of psychotic symptoms in female MDD patients was 10.97%. The findings revealed significant differences between MDD female patients with psychotic symptoms and non-PD female patients in the following areas: higher HAMD scores, higher HAMA scores, more severe anxiety and an increased risk of suicide attempts. Further logistic regression analysis showed that psychotic symptoms were associated with higher thyroid-stimulating hormone (TSH) levels and an odds ratio of 1.168.

CONCLUSIONS

Our findings supported the hypothesis that higher TSH levels were correlated with psychotic symptoms in female MDD patients. Therefore, serum TSH levels may be a potential biomarker of PD in female MDD patients. In addition, we found that PD was closely associated with suicide attempts and lipid levels, but did not reach statistical significance.

Equivalence Class Formation in Adults with Severe Behavioral Problems

Stimulus equivalence is a behavioral phenomenon that has been related to complex human behavior (e.g., remembering, cognitive functioning, and symbolic behavior). As a rule, people diagnosed with severe mental disorders (e.g., schizophrenia, bipolar disorder) that exhibit delusional and hallucinatory behavior, and disorganized speech have shown cognitive impairment (e.g., processing speed, reasoning/problem solving). Not enough research has analyzed the stimulus equivalence performance in this population. This study aims to investigate the stimulus equivalence performance in adults diagnosed with severe mental disorders. In particular, this study analyzes the many-to-one (MTO) and one-to-many (OTM) training structures effects, and the simultaneous (SIM) and the simple-to-complex (STC) training and testing protocol effects on equivalence class formation in this population. To achieve it, we analyzed the behavior of 18 participants diagnosed with severe mental disorders in three different conditions (Condition 1 OTM/SIM; 2 MTO/SIM; and 3 MTO/STC). Behavior consistent with stimulus equivalence was found in 11 out of 13 participants who had finished the study (5 participants decided to leave before completing the tasks). STC yielded better results than the SIM protocol. No differences were found between MTO and OTM training structures. Implications and suggestions for further research have been discussed.

Depression affects working memory performance: A Functional Near Infrared Spectroscopy (fNIRS) Study

Depression is a complex disorder that can be caused by psychosocial and biological conditions, and it not only affects to emotional life, but also cognitive functions, specifically the executive functions, attention, psychomotor speed, and memory. Some results of the studies in the literature show that depressed individuals perform worse on cognitive tasks than healthy individuals, while others indicate that there is no difference. Moreover, there is also no consensus about the depressed people brain functionalities. We aimed to compare the people who has high and low depression score measured with Beck Depression Inventory in terms of their working memory performance by using n-back paradigm and their brain activity by using optical imaging with this study. The age of lower BDI group (n = 11) is 23,9 ± 3,04 and higher BDI group (n = 23) is 22,2 + 2,28. The fNIRS were recorded from each subject while neutral words-faces and emotional words-faces are given to the subjects in the visuospatial 2-back WM task. There are no significant differences between the two groups behaviorally during the working memory performance, however, the high BDI group's PFC activation in right hemisphere is founded to be higher than the lower group. Our findings support the literature who is claiming the difference brain activity in depressed brain but not cognitive performance. Though, the small group size and the task difficulty (easy) could be the explanation of the behavioral results.

Brain-wide versus genome-wide vulnerability biomarkers for severe mental illnesses

Severe mental illnesses (SMI), including major depressive (MDD), bipolar (BD), and schizophrenia spectrum (SSD) disorders have multifactorial risk factors and capturing their complex etiopathophysiology in an individual remains challenging. Regional vulnerability index (RVI) was used to measure individual's brain-wide similarity to the expected SMI patterns derived from meta-analytical studies. It is analogous to polygenic risk scores (PRS) that measure individual's similarity to genome-wide patterns in SMI. We hypothesized that RVI is an intermediary phenotype between genome and symptoms and is sensitive to both genetic and environmental risks for SMI. UK Biobank sample of N = 17,053/19,265 M/F (age = 64.8 ± 7.4 years) and an independent sample of SSD patients and controls (N = 115/111 M/F, age = 35.2 ± 13.4) were used to test this hypothesis. UKBB participants with MDD had significantly higher RVI-MDD (Cohen's d = 0.20, p = 1 × 10-23 ) and PRS-MDD (d = 0.17, p = 1 × 10-15 ) than nonpsychiatric controls. UKBB participants with BD and SSD showed significant elevation in the respective RVIs (d = 0.65 and 0.60; p = 3 × 10-5 and .009, respectively) and PRS (d = 0.57 and 1.34; p = .002 and .002, respectively). Elevated RVI-SSD were replicated in an independent sample (d = 0.53, p = 5 × 10-5 ). RVI-MDD and RVI-SSD but not RVI-BD were associated with childhood adversity (p < .01). In nonpsychiatric controls, elevation in RVI and PRS were associated with lower cognitive performance (p < 10-5 ) in six out of seven domains and showed specificity with disorder-associated deficits. In summary, the RVI is a novel brain index for SMI and shows similar or better specificity for SMI than PRS, and together they may complement each other in the efforts to characterize the genomic to brain level risks for SMI.

Association of serum lipid levels with psychotic symptoms in young, first-episode and drug naïve outpatients with major depressive disorder: A large-scale cross-sectional study

BACKGROUND

Major depressive disorder (MDD) patients with psychotic symptoms have more complex clinical symptoms and higher relapse rates. The purpose of this study was to compare serum lipid differences between psychotic major depressive disorder (PMD) and non-psychotic major depressive disorder (NPMD) in a large sample of young first-episode drug naïve (FEDN) patients.

METHODS

We recruited 1289 young MDD patients. Socio-demographic information, clinical data, and lipid parameters were collected. The Hamilton Depression Rating Scale, the Hamilton Anxiety Rating Scale, and the positive symptom subscale of the Positive and Negative Syndrome Scale were used to assess patients' depressive, anxiety and psychotic symptoms, respectively.

RESULTS

Compared with the NPMD group, the PMD group had higher HAMD, HAMA scores, and higher TC, TG, and LDL-C levels. Correlation analysis showed that psychotic symptoms were significantly associated with the total score of HAMD and HAMA, and the levels of serum lipid. In addition, logistic regression analysis found that TC was associated with psychotic symptoms in young FEDN MDD patients.

CONCLUSION

Our results suggest TC levels may be associated with psychotic symptoms in young MDD patients. The importance of regular psychotic symptom assessment in young MDD patients with high TC levels should be taken into account.

Variation in Thyroid-Stimulating Hormone and Cognitive Disorders in Unmedicated Middle-Aged Patients with Major Depressive Disorder: A Proton Magnetic Resonance Spectroscopy Study

Background

Middle-aged (45-59 years old) patients with major depressive disorder (MDD) have a predilection for dementia and cognitive disorders (CDs); however, the characteristics and mechanisms of CDs in these patients remain unclear. There are also known connections between thyroid-stimulating hormone (TSH), brain biochemical metabolism, and cognitive function (CF); however, there is scanty of information about these connections in middle-aged MDD patients.

Methods

Cognitive assessment was performed on 30 first-episode, untreated middle-aged patients with MDD and 30 well-matched healthy controls (HCs) using the MATRICS Consensus Cognitive Battery (MCCB). N-acetyl aspartate (NAA)/creatine (Cr) and choline (Cho)/Cr ratios in the prefrontal cortex (PFC) and cerebellum were also obtained via proton magnetic resonance spectroscopy (¹H-MRS), and the TSH level was measured by chemiluminescence analysis.

Results

MDD patients presented significantly lower processing speed, working memory, verbal learning, reasoning problem-solving, visual learning, and composite cognition scores than controls, with a statistically lower NAA/Cr ratio in the right cerebellum. Age was positively related to reasoning problem-solving in the MDD group (r = 0.6249, p = 0.0220). Education also showed a positive association with visual learning, social cognition, and composite cognition. The 24-item Hamilton Depression Rating Scale (HDRS-24) score was negatively related to all domains of CF. TSH levels were markedly decreased in the MDD group, and a positive connection was determined between the NAA/Cr ratio in the right PFC and the TSH level.

Conclusions

Middle-aged MDD patients have multidimensional CDs. There are changes in PFC and cerebellar biochemical metabolism in middle-aged patients with MDD, which may be related to CDs or altered TSH levels.

Similarities and differences in working memory and neurometabolism of obsessive-compulsive disorder and major depressive disorder

BACKGROUND

Obsessive-compulsive disorder (OCD) and major depressive disorder (MDD) both showed cognitive impairment, and the altered neurometabolic may associate with cognitive impairment. However, there are limited comparative working memory (WM) and neuroimaging studies on these two disorders. Therefore, we investigated the characteristics of WM and neurometabolic changes in patients with OCD and MDD.

METHODS

A total of 64 unmedicated patients (32 OCD and 32 MDD), and 33 healthy controls (HC) were included to conduct WM assessment comprising Digit Span Test (DST), 2-back task and Stroop Color and Word Test (SCWT). Additionally, all subjects underwent protons magnetic resonance spectroscopy (¹H-MRS) to collect neurometabolic ratios of N-acetyl aspartate (NAA) and choline-containing compounds (Cho) to creatine (Cr) in the prefrontal cortex (PFC) and lentiform nucleus (LN). Finally, differential and correlation analysis were conducted to investigate their characteristics and relationships.

RESULTS

Compared with HC, both OCD and MDD patients exhibited a lower accuracy rate in the 2-back task, and only MDD patients performed worse in DST scores and longer reaction times in SCWT (all p < 0.05). Both OCD and MDD patients had lower NAA/Cr ratios in bilateral PFC (all p < 0.05). And the decreased NAA/Cr ratios in right PFC were positively correlated to DST scores in MDD group (r = 0.518, p = 0.003).

CONCLUSIONS

Both OCD and MDD showed WM impairment and neurometabolic alterations in PFC. Besides, MDD performed more severe and broader WM impairment compared to OCD. Moreover, the dysfunction of PFC may underlie the neural basis of WM impairment in MDD.

A Machine-Learning-Algorithm-Based Prediction Model for Psychotic Symptoms in Patients with Depressive Disorder

Psychotic symptoms are rarely concurrent with the clinical manifestations of depression. Additionally, whether psychotic major depression is a subtype of major depression or a clinical syndrome distinct from non-psychotic major depression remains controversial. Using data from the Research on Asian Psychotropic Prescription Patterns for Antidepressants, we developed a machine-learning-algorithm-based prediction model for concurrent psychotic symptoms in patients with depressive disorders. The advantages of machine learning algorithms include the easy identification of trends and patterns, handling of multi-dimensional and multi-faceted data, and wide application. Among 1171 patients with depressive disorders, those with psychotic symptoms were characterized by significantly higher rates of depressed mood, loss of interest and enjoyment, reduced energy and diminished activity, reduced self-esteem and self-confidence, ideas of guilt and unworthiness, psychomotor agitation or retardation, disturbed sleep, diminished appetite, and greater proportions of moderate and severe degrees of depression compared to patients without psychotic symptoms. The area under the curve was 0.823. The overall accuracy was 0.931 (95% confidence interval: 0.897-0.956). Severe depression (degree of depression) was the most important variable in the prediction model, followed by diminished appetite, subthreshold (degree of depression), ideas or acts of self-harm or suicide, outpatient status, age, psychomotor retardation or agitation, and others. In conclusion, the machine-learning-based model predicted concurrent psychotic symptoms in patients with major depression in connection with the "severity psychosis" hypothesis.

Association of serum lipid levels with psychotic symptoms in first-episode and drug naïve outpatients with major depressive disorder: a large-scale cross-sectional study

Background Major depressive disorder (MDD) is a prevalent psychiatric disorder, with increasing evidence that patients with MDD display psychotic symptoms. Studies have shown the association between lipid levels and MDD, but few have explored the relationship between lipids and psychotic symptoms in MDD. The objective of this study was to compare the differences of lipid levels between patients with psychotic major depressive disorder (PMD) and those with non-psychotic major depressive disorder (NPMD) in first-episode and drug-naive (FEDN) MDD patients. Methods A total of 1718 outpatients with FEDN MDD were recruited. In addition to collecting basic information, their blood specimens were also collected to detect serum TC, HDL-C, TG, and LDL-C. The Hamilton depression scale (HAMD), Hamilton anxiety scale (HAMA), and Positive and Negative Syndrome Scale (PANSS) were used to assess their depression, anxiety, and psychotic symptoms respectively. Results Compared to those with NPMD, those with PMD had higher scores on HAMD, HAMA, and more elevated serum TC, TG, and LDL-C levels, but lower HDL-C levels (all p < 0.05). Further logistic regression analysis showed that TG, the severity of depressive and anxiety symptoms were significantly associated with psychotic symptoms (p < 0.05). Limitations No causal relationship could be drawn due to the cross-sectional design. Conclusions Psychotic symptoms in patients with MDD may be predicted by lipid levels in the future. Our findings suggest that TG seems to predict the presence of current psychotic features among patients with FEDN MDD.

Evaluating endophenotypes for bipolar disorder

BACKGROUND

Phenotypic heterogeneity is a major impediment to the elucidation of the neurobiology and genetics of bipolar disorder. Endophenotype could help in reducing heterogeneity by defining biological traits that are more direct expressions of gene effects. The aim of this review is to examine the recent literature on clinical, epidemiological, neurobiological, and genetic findings and to select and evaluate candidate endophenotypes for bipolar disorder. Evaluating putative endophenotype could be helpful in better understanding the neurobiology of bipolar disorder by improving the definition of bipolar-related phenotypes in genetic studies. In this manner, research on endophenotypes could be useful to improve psychopathological diagnostics in the long-run by dissecting psychiatric macro phenotypes into biologically valid components.

MAIN BODY

The associations among the psychopathological and biological endophenotypes are discussed with respect to specificity, temporal stability, heritability, familiarity, and clinical and biological plausibility. Numerous findings regarding brain function, brain structure, neuropsychology and altered neurochemical pathways in patients with bipolar disorder and their relatives deserve further investigation. Overall, major findings suggest a developmental origin of this disorder as all the candidate endophenotypes that we have been able to select are present both in the early stages of the disorder as well as in subjects at risk.

CONCLUSIONS

Among the stronger candidate endophenotypes, we suggest circadian rhythm instability, dysmodulation of emotion and reward, altered neuroimmune state, attention and executive dysfunctions, anterior cingulate cortex thickness and early white matter abnormalities. In particular, early white matter abnormalities could be the result of a vulnerable brain on which new stressors are added in young adulthood which favours the onset of the disorder. Possible pathways that lead to a vulnerable brain are discussed starting from the data about molecular and imaging endophenotypes of bipolar disorder.

Cognitive mechanisms underlying depressive disorders in ADHD: A systematic review

The risk for major depressive disorder (MDD) is considerably increased in young adults with attention-deficit/hyperactivity disorder (ADHD) but underlying mechanisms are poorly understood. This review explores ADHD-specific neurocognitive impairments as possible underlying mechanisms for ADHD-depression comorbidity. Two systematic literature searches were conducted in EBSCOhost, PubMED, and Cochrane Reviews databases according to PRISMA guidelines. The first search identified 18 meta-analyses of cross-sectional and longitudinal studies on cognitive dysfunctions in MDD across the lifespan. The second search identified six original studies on reaction time variability in MDD. During acute depression, children and adults showed cognitive deficits that overlapped with some of the ADHD-related impairments. Findings from remitted patients, high-risk individuals, and few prospective studies suggest that a subset of these shared impairments, specifically executive dysfunctions (selective attention, verbal fluency, working memory) and long-term memory problems, are candidate pre-existing risk markers of depression. We discuss if and how these specific neurocognitive mechanisms may mediate developmental pathways from ADHD to depression. If replicated by longitudinal studies, these findings may guide future prevention strategies.

Cognition in offspring of parents with psychotic and non-psychotic severe mental illness

BACKGROUND

Cognitive impairment is a feature of severe mental illness (SMI; schizophrenia, bipolar disorder, major depressive disorder). Psychotic forms of SMI may be associated with greater cognitive impairment, but it is unclear if this differential impairment pre-dates illness onset or whether it reflects a consequence of the disorder. To establish if there is a developmental impairment related to familial risk of psychotic SMI, we investigated cognition in offspring of parents with psychotic and non-psychotic SMI.

METHOD

Participants included 360 children and youth (mean age 11.10, SD 4.03, range 6-24), including 68 offspring of parents with psychotic SMI, 193 offspring of parents with non-psychotic SMI, and 99 offspring of control parents. The cognitive battery assessed a range of functions using standardized tests and executive function tasks from the Cambridge Automated Neuropsychological Test Battery.

RESULTS

Compared to controls, offspring of parents with psychotic SMI performed worse on overall cognition (β = -0.32; p < 0.001) and 6 of 15 cognitive domains, including verbal intelligence, verbal working memory, processing speed, verbal learning and memory, verbal fluency, and sustained attention. Offspring of parents with non-psychotic SMI performed worse than controls on 3 of the 15 domain specific cognitive tests, including verbal intelligence, visual memory and decision-making.

CONCLUSIONS

Widespread mild-to-moderate cognitive impairments are present in young offspring at familial risk for transdiagnostic psychotic SMI. Offspring at familial risk for non-psychotic SMI showed fewer and more specific impairments in the domains of verbal intelligence, visual memory and decision-making.

A 2-year longitudinal study of neuropsychological functioning, psychosocial adjustment and rehospitalisation in schizophrenia and major depression

Neuropsychological functioning turns out to be a rate-limiting factor in psychiatry. However, little is known when comparing neuropsychological and psychosocial functioning in inpatients with schizophrenia or severe depression in their treatment pathways including add-on psychoeducation or the latter combined with cognitive behavioral therapy up to 2-year follow-up. To evaluate this question, we investigated these variables in two randomised controlled trials including 196 patients with DSM-IV schizophrenia and 177 patients with major depression. Outcome measures were assessed in the hospital at pre- and posttreatment and following discharge until 2-year follow-up. We focused on neuropsychological and psychosocial functioning regarding its differences and changes over time in data of two pooled trials. There were significant time effects indicating gains in knowledge about the illness, short and medium-term memory (VLMT) and psychosocial functioning (GAF), however, the latter was the only variable showing a time x study/diagnosis interaction effect at 2-year follow-up, showing significant better outcome in depression compared to schizophrenia. Moderator analysis showed no changes in psychosocial and neuropsychological functioning in schizophrenia and in affective disorders due to age, duration of illness or sex. Looking at the rehospitalisation rates there were no significant differences between both disorders. Both groups treated with psychoeducation or a combination of psychoeducation and CBT improved in neuropsychological and psychosocial functioning as well as knowledge about the illness at 2-year follow-up, however, patients with major depression showed greater gains in psychosocial functioning compared to patients with schizophrenia. Possible implications of these findings were discussed.

Prevalence and related factors of suicide attempts in first-episode and untreated Chinese Han outpatients with psychotic major depression

BACKGROUND

Major depressive depression (MDD) is often accompanied by suicidal behavior. Increasing evidence shows that MDD patients display psychotic symptoms. However, the relationship between psychotic symptoms and suicide attempt in MDD has not been reported. Therefore, this study was to identify the prevalence and associated factors of suicide attempts in first-episode and untreated Chinese Han outpatients comorbid with psychotic major depression (PMD).

METHODS

1718 first-episode and untreated MDD outpatients were assessed with Positive Symptom Scale of Positive and Negative Syndrome Scale (PANSS), the 17-item Hamilton Depression Scale, Hamilton Anxiety Scale, and clinical global impression of severity scale (CGI-S). Some glycolipid metabolism and thyroid hormone parameters were measured.

RESULTS

In MDD patients, the percentage of PMD was 10.0%. The incidence of attempted suicide in PMD patients was 51.5%, which was more than 3 times higher than that in non-PMD patients (16.7%). In PMD patients, compared to non-attempters, suicide attempters were older, had a longer course of disease, scored higher on all scales, as well as had higher levels of thyroid stimulating hormone (TSH), thyroid peroxidases antibody, anti-thyroglobulin and blood glucose. PANSS positive symptom, CGI, diastolic blood pressure and TSH were independently associated with suicide attempts of PMD.

CONCLUSIONS

PMD patients have a higher prevalence of suicide attempt than non-PMD patients. Some demographic and clinical parameters are relevant factors for suicide attempt in PMD patients.

Long-term Changes in Cognitive Functioning in Individuals With Psychotic Disorders: Findings From the Suffolk County Mental Health Project

IMPORTANCE

It remains uncertain whether people with psychotic disorders experience progressive cognitive decline or normal cognitive aging after first hospitalization. This information is essential for prognostication in clinical settings, deployment of cognitive remediation, and public health policy.

OBJECTIVE

To examine long-term cognitive changes in individuals with psychotic disorders and to compare age-related differences in cognitive performance between people with psychotic disorders and matched control individuals (ie, individuals who had never had psychotic disorders).

DESIGN, SETTING, AND PARTICIPANTS

The Suffolk County Mental Health Project is an inception cohort study of first-admission patients with psychosis. Cognitive functioning was assessed 2 and 20 years later. Patients were recruited from the 12 inpatient facilities of Suffolk County, New York. At year 20, the control group was recruited by random digit dialing and matched to the clinical cohort on zip code and demographics. Data were collected between September 1991 and July 2015. Analysis began January 2016.

MAIN OUTCOMES AND MEASURES

Change in cognitive functioning in 6 domains: verbal knowledge (Wechsler Adult Intelligence Scale-Revised vocabulary test), verbal declarative memory (Verbal Paired Associates test I and II), visual declarative memory (Visual Reproduction test I and II), attention and processing speed (Symbol Digit Modalities Test-written and oral; Trail Making Test [TMT]-A), abstraction-executive function (Trenerry Stroop Color Word Test; TMT-B), and verbal fluency (Controlled Oral Word Association Test).

RESULTS

A total of 705 participants were included in the analyses (mean [SD] age at year 20, 49.4 [10.1] years): 445 individuals (63.1%) had psychotic disorders (211 with schizophrenia spectrum [138 (65%) male]; 164 with affective psychoses [76 (46%) male]; 70 with other psychoses [43 (61%) male]); and 260 individuals (36.9%) in the control group (50.5 [9.0] years; 134 [51.5%] male). Cognition in individuals with a psychotic disorder declined on all but 2 tests (average decline: d = 0.31; range, 0.17-0.54; all P < .001). Cognitive declines were associated with worsening vocational functioning (Visual Reproduction test II: r = 0.20; Symbol Digit Modalities Test-written: r = 0.25; Stroop: r = 0.24; P < .009) and worsening negative symptoms (avolition: Symbol Digit Modalities Test-written: r = -0.24; TMT-A: r = -0.21; Stroop: r = -0.21; all P < .009; inexpressivity: Stroop: r = -0.22; P < .009). Compared with control individuals, people with psychotic disrders showed age-dependent deficits in verbal knowledge, fluency, and abstraction-executive function (vocabulary: β = -0.32; Controlled Oral Word Association Test: β = -0.32; TMT-B: β = 0.23; all P < .05), with the largest gap among participants 50 years or older.

CONCLUSIONS AND RELEVANCE

In individuals with psychotic disorders, most cognitive functions declined over 2 decades after first hospitalization. Observed declines were clinically significant. Some declines were larger than expected due to normal aging, suggesting that cognitive aging in some domains may be accelerated in this population. If confirmed, these findings would highlight cognition as an important target for research and treatment during later phases of psychotic illness.

Electroconvulsive therapy modulates grey matter increase in a hub of an affect processing network

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We here present a structural neuroimaging study reporting on a large multi-site patient sample with unipolar depression that underwent ECT.

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Patients showed grey matter increases in the medial temporal lobe.

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Connectivity modeling revealed that this altered brain region was involved in networks related to affect processing and memory.

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This provides a potential explanation, how these structural changes during ECT are involved in both main and side effects of the treatment.

A growing number of recent studies has suggested that the neuroplastic effects of electroconvulsive therapy (ECT) might be prominent enough to be detected through changes of regional gray matter volumes (GMV) during the course of the treatment. Given that ECT patients are difficult to recruit for imaging studies, most publications, however, report only on small samples. Addressing this challenge, we here report results of a structural imaging study on ECT patients that pooled patients from five German sites.

Whole-brain voxel-based morphometry (VBM) analysis was performed to detect structural differences in 85 patients with unipolar depression before and after ECT, when compared to 86 healthy controls. Both task-independent and task-dependent physiological whole-brain functional connectivity patterns of these regions were modeled using additional data from healthy subjects. All emerging regions were additionally functionally characterized using the BrainMap database.

Our VBM analysis detected a significant increase of GMV in the right hippocampus/amygdala region in patients after ECT compared to healthy controls. In healthy subjects this region was found to be enrolled in a network associated with emotional processing and memory. A region in the left fusiform gyrus was additionally found to have higher GMV in controls when compared with patients at baseline. This region showed minor changes after ECT.

Our data points to a GMV increase in patients post ECT in regions that seem to constitute a hub of an emotion processing network. This appears as a plausible antidepressant mechanism and could explain the efficacy of ECT not only in the treatment of unipolar depression, but also of affective symptoms across heterogeneous disorders.

Cognitive Deficits in Older Adults With Psychotic Depression: A Meta-Analysis

A major depressive disorder with psychotic features, that is, psychotic depression (PD), is often accompanied by cognitive deficits, particularly in older patients. We aimed to assess to what extent various cognitive domains are affected in older patients with PD compared to those with nonpsychotic depression (NPD). Therefore, a systematic search was conducted in Medline, Embase, Web of Science, the Cumulative Index to Nursing and Allied Literature (CINAHL), Google Scholar, and Cochrane for all relevant studies. Hereafter, we conducted a meta-analysis of seven studies on cognitive deficits in older adults (55+ years), comparing patients with PD and patients with NPD. Compared to patients with NPD, those with PD not only showed a significantly poorer performance on overall cognitive function, with a Hedges' g effect size of -0.34 (95% confidence interval: -0.56; -0.12; p = 0.003), but also on nearly all separate cognitive domains, with Hedges' g effect sizes ranging from -0.26 to -0.64 (all p's <0.003), of which attention was most adversely affected. Verbal fluency showed no significant effect, although this analysis may have been underpowered. The funnel plot suggested no significant publication bias (Egger test intercept: -2.47; 95% confidence interval: -5.50; 0.55; p = 0.09). We conclude that older patients with PD show more cognitive deficits on all cognitive domains, except for verbal fluency, compared to patients with NPD. It is crucial that clinicians and researchers take cognitive deficits into consideration in older adults with PD.

Diagnostic Issues of Depressive Disorders from Kraepelinian Dualism to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition

Because the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) was mainly influenced by the neo-Kraepelinian approach, its categorical approach to defining mental disorders has been criticized from the viewpoint of etiological neutrality. In the context of bridging the gap between "presumed etiologies-based symptomatology" and "identifiable pathophysiological etiologies," the content in 5th edition, the DSM-5, has been revised to incorporate a combination of categorical and dimensional approaches. The most remarkable change of note regarding the diagnostic classification of depressive disorders in the DSM-5 is the splitting of mood disorders into bipolar disorders and depressive disorders, which is in accordance with the deconstruction of the Kraepelinian dualism for psychoses. The transdiagnostic specifiers "with mixed features," "with psychotic features," and "with anxious distress" are introduced to describe the relationships of depressive disorders with bipolar disorders, schizophrenia, and generalized anxiety disorder, respectively, in a dimensional manner. The lowering of the diagnostic threshold for major depressive disorder (MDD) may be caused by the addition of "hopelessness" to the subjective descriptors of depressive mood and the elimination of "bereavement exclusion" from the definition of MDD. Since the heterogeneity of MDD is equivalent to the Wittgensteinian "games" analogy, the different types of MDD are related not by a single essential feature but rather by "family resemblance." Network analyses of MDD symptoms may therefore need further review to elucidate the connections among interrelated symptoms and other clinical elements.

Distinct Expression Pattern of Epigenetic Machinery Genes in Blood Leucocytes and Brain Cortex of Depressive Patients

In major depressive disorder (MDD), altered gene expression in brain cortex and blood leucocytes may be due to aberrant expression of epigenetic machinery coding genes. Here, we explore the expression of these genes both at the central and peripheral levels. Using real-time quantitative PCR technique, we first measured expression levels of genes encoding DNA and histone modifying enzymes in the dorsolateral prefrontal cortex (DLPFC) and cingulate cortex (CC) of MDD patients (n = 24) and healthy controls (n = 12). For each brain structure, transcripts levels were compared between subject groups. In an exploratory analysis, we then compared the candidate gene expressions between a subgroup of MDD patients with psychotic characteristics (n = 13) and the group of healthy subjects (n = 12). Finally, we compared transcript levels of the candidate genes in blood leucocytes between separate samples of MDD patients (n = 17) and healthy controls (n = 16). In brain and blood leucocytes of MDD patients, we identified an overexpression of genes encoding enzymes which transfer repressive transcriptional marks: HDAC4-5-6-8 and DNMT3B in the DLPFC, HDAC2 in the CC and blood leucocytes. In the DLPFC of patients with psychotic characteristics, two genes (KAT2A and UBE2A) were additionally overexpressed suggesting a shift to a more transcriptionally permissive conformation of chromatin. Aberrant activation of epigenetic repressive systems may be involved in MDD pathogenesis both in brain tissue and blood leucocytes.

Cognitive Deficits in Psychotic Disorders: A Lifespan Perspective

Individuals with disorders that include psychotic symptoms (i.e. psychotic disorders) experience broad cognitive impairments in the chronic state, indicating a dimension of abnormality associated with the experience of psychosis. These impairments negatively impact functional outcome, contributing to the disabling nature of schizophrenia, bipolar disorder, and psychotic depression. The robust and reliable nature of cognitive deficits has led researchers to explore the timing and profile of impairments, as this may elucidate different neurodevelopmental patterns in individuals who experience psychosis. Here, we review the literature on cognitive deficits across the life span of individuals with psychotic disorder and psychotic-like experiences, highlighting the dimensional nature of both psychosis and cognitive ability. We identify premorbid generalized cognitive impairment in schizophrenia that worsens throughout development, and stabilizes by the first-episode of psychosis, suggesting a neurodevelopmental course. Research in affective psychosis is less clear, with mixed evidence regarding premorbid deficits, but a fairly reliable generalized deficit at first-episode, which appears to worsen into the chronic state. In general, cognitive impairments are most severe in schizophrenia, intermediate in bipolar disorder, and the least severe in psychotic depression. In all groups, cognitive deficits are associated with poorer functional outcome. Finally, while the generalized deficit is the clearest and most reliable signal, data suggests specific deficits in verbal memory across all groups, specific processing speed impairments in schizophrenia and executive functioning impairments in bipolar disorder. Cognitive deficits are a core feature of psychotic disorders that provide a window into understanding developmental course and risk for psychosis.

Neuropsychological Performance in Alcohol Dependent Patients: A One-Year Longitudinal Study

OBJECTIVE

Despite several studies that have highlighted the harmful effects of alcohol consumption on cognitive functions it remains unclear whether certain brain areas are more sensitive than others are or whether alcohol causes widespread cognitive deficit. Moreover, the role of continued abstinence has yet to be clarified regarding the quality of recovery on the different cognitive domains. The aim of this 1-year longitudinal study was to evaluate the recovery of cognitive deficits in the medium (6 months) and long term (12 months) after the interruption of drinking.

METHODS

Forty-one alcohol-dependent patients were recruited from two outpatient treatment facilities and cognitive functions were compared on a control group of forty healthy controls. The patients were then re-assessed at 6 and 12 months. Changes in neuropsychological measures were evaluated with repeated measures analysis of variance (ANOVA). We also compared 1-year follow-up scores with control data (unpaired t tests) to identify tests on which significant differences persisted.

RESULTS

Patients performed significantly worse than controls in all cognitive domains investigated and this cognitive impairment was evident in recently abstinent patients. A year of abstinence resulted in a significant improvement in all cognitive domains assessed after detoxification from alcohol. After year 1, alcoholic subjects had returned to normal levels compared to healthy controls on all domains except for general non-verbal intelligence, verbal memory and some visuospatial skills.

CONCLUSION

Our results support the hypothesis of widespread impairment resulting from alcohol consumption. The recovery of cognitive functions is not homogeneous during prolonged abstinence.

Epidemiology of psychotic depression - systematic review and meta-analysis

Large amount of data have been published on non-psychotic depression (NPD), schizophrenia (SZ), and bipolar disorder, while psychotic depression (PD) as an own entity has received much smaller attention. We performed a systematic review and meta-analyses on epidemiology, especially incidence and prevalence, risk factors, and outcomes of PD. A systematic search to identify potentially relevant studies was conducted using four electronic databases and a manual search. The search identified 1764 unique potentially relevant articles, the final study included 99 articles. We found that the lifetime prevalence of PD varies between 0.35% and 1%, with higher rates in older age. Onset age of PD was earlier than that of NPD in younger samples, but later in older samples. There were no differences in gender distribution in PD v. NPD, but higher proportion of females was found in PD than in SZ or in psychotic bipolar disorder (PBD). Risk factors have rarely been studied, the main finding being that family history of psychosis and bipolar disorder increases the risk of PD. Outcomes of PD were mostly worse when compared with NPD, but better compared with SZ and schizoaffective disorder. The outcome compared with PBD was relatively similar, and somewhat varied depending on the measure of the outcome. Based on this review, the amount of research on PD is far from that of NPD, SZ, and bipolar disorder. Based on our findings, PD seems distinguishable from related disorders and needs more scientific attention.

Correlations between working memory impairment and neurometabolites of prefrontal cortex and lenticular nucleus in patients with major depressive disorder

BACKGROUND

The mechanism of working memory (WM) impairment in MDD remains unclear. We aimed to find out the mechanism by using neuropsychological tests and proton magnetic resonance spectroscopy (1H-MRS).

METHODS

31 MDD patients and 31 healthy controls were recruited in our study. The WM performance and neurometabolite ratios of prefrontal cortex (PFC) and lenticular nucleus (LN) between two groups were evaluated and compared. And the correlations between abnormal neurometabolite ratios and WM dysfunction were computed.

RESULTS

Scores of SDMT, DST(forwards), VRS and 2-back Task(accuracy rate) in MDD were lower than HCs. NAA/Cr ratios of bilateral PFC in MDD were significantly lower than HCs, while no significant differences showed in NAA/Cr ratios of LN and Cho/Cr, mI/Cr values of the bilateral PFC and LN between two groups. And for MDD patients, NAA/Cr ratios in the right PFC were positively correlated with scores of DST (Forwards).

CONCLUSIONS

Our findings suggest that depressed patients may have impairments in working memory, including phonological loop, visual-spatial sketchpad, episodic buffer and central executive. And the impairment of verbal WM and WM capacity may be associated with the abnormal neurometabolites in the right PFC.

Non literal language comprehension in a large sample of first episode psychosis patients in adulthood

To date no data still exist on the comprehension of figurative language in the early phases of psychosis. The aim of this study is to investigate for the first time the comprehension of metaphors and idioms at the onset of the illness. Two-hundred-twenty eight (228) first episode psychosis (FEP) patients (168 NAP, non-affective psychosis; 60 AP, affective psychosis) and 70 healthy controls (HC) were assessed. Groups were contrasted on: a) type of stimulus (metaphors vs idioms) and b) type of response (OPEN = spontaneous explanations vs CLOSED = multiple choice answer). Moreover, a machine learning (ML) approach was adopted to classifying participants. Both NAP and AP had a poorer performance on OPEN metaphors and idioms compared to HC, with worse results on spontaneous interpretation of idioms than metaphors. No differences were observed between NAP and AP in CLOSED tasks. The ML approach points at CLOSED idioms as the best discriminating variable, more relevant than the set of pre-frontal and IQ scores. Deficits in non-figurative language may represent a core feature of psychosis. The possibility to identify linguistic features discriminating FEP may support the early recognition of patients at risk to develop psychosis, guiding provision of personalized and timely interventions.

Psychotic (delusional) depression and completed suicide: a systematic review and meta-analysis

BACKGROUND

It remains unclear whether psychotic features increase the risk of completed suicides in unipolar depression. The present systematic review coupled with a meta-analysis attempts to elucidate whether unipolar psychotic major depression (PMD) compared to non-PMD presents higher rates of suicides.

METHODS

A systematic search was conducted in Scopus, PubMed, and "gray literature" for all studies providing data on completed suicides in PMD compared to non-PMD, and the findings were then subjected to meta-analysis. All articles were independently extracted by two authors using predefined data fields.

RESULTS

Nine studies with 33,873 patients, among them 828 suicides, met our inclusion criteria. PMD compared to non-PMD presented a higher lifetime risk of completed suicides with fixed-effect pooled OR 1.21 (95% CI 1.04-1.40). In a sub-analysis excluding a very large study (weight = 86.62%), and comparing 681 PMD to 2106 non-PMD patients, an even higher pooled OR was found [fixed-effect OR 1.69 (95% CI 1.16-2.45)]. Our meta-analysis may provide evidence that the presence of psychosis increases the risk of suicide in patients suffering from severe depression. The data are inconclusive on the contribution of age, mood congruence, comorbidity, and suicide method on PMD's suicide risk. The lack of accurate diagnosis at the time of suicide, PMD's diagnostic instability, and the use of ICD-10 criteria constitute the main study limitations.

CONCLUSIONS

The presence of psychosis in major depression should alert clinicians for the increased risk of completed suicide. Thus, the implementation of an effective treatment both for psychotic depression and patients' suicidality constitutes a supreme priority.

Prospective memory deficits in patients with depression: A meta-analysis

BACKGROUND

Prospective memory (PM) can be impaired in patients with psychiatric disorders including depression. This meta-analysis systematically examined PM in patients with depression.

METHODS

The meta-analysis was conducted according to the guidelines from Strengthening the Reporting of Observational studies in Epidemiology (STROBE). Case-control studies on PM in patients with depression were included. Standardized mean differences (SMDs) and 95% confidence interval (CI) were calculated using random effect models.

RESULTS

Ten case-control studies (n = 596) comparing patients with depression (n = 299) with healthy controls (n = 297) were included in the analyses. Compared with healthy controls, patients with depression had significant impairment in event-based PM (EBPM) [8 trials, n = 436; SMD: -0.87 (95%CI: -1.43, -0.31), P = 0.002; I² = 87%]. Significance was observed after removing two outlier trials [SMD: -0.44 (95%CI: -0.69, -0.20), P = 0.0004; I² = 23%] and also in 8 out of the 13 subgroup analyses. Similarly, time-based PM (TBPM) was significantly impaired in patients with depression [4 trials, n = 239; SMD: -0.89 (95%CI: -1.46, -0.31), P = 0.003; I² = 78%] when compared with healthy controls.

CONCLUSIONS

This meta-analysis showed that both TBPM and EBPM appeared to be impaired in patients with depression.

Clinical Validation of the Psychotic Depression Assessment Scale, Hamilton Depression Rating Scale-6, and Brief Psychiatric Rating Scale-5: Results from the Clinical Research Center for Depression Study

OBJECTIVE

The aim of this study was to validate the psychotic depression assessment scale (PDAS), which includes the six-item melancholia subscale from the Hamilton depression rating scale (HAMD-6) and the five-item psychosis subscale from the brief psychiatric rating scale (BPRS-5). Data from the Clinical Research Center for Depression (CRESCEND) study, which is a 52-week naturalistic trial, were analyzed.

METHODS

Fifty-two patients with psychotic depression from the CRESCEND study met our inclusion criteria. The patients underwent the following psychometric assessments: the PDAS, including HAMD-6 and BPRS-5, the clinical global impression scales, the HAMD, the positive symptom subscale, and the negative symptom subscale. Assessments were performed at the baseline and then at weeks 1, 2, 4, 8, 12, 24, and 52. Spearman correlation analyses were used to assess the clinical validity and responsiveness of the PDAS.

RESULTS

The clinical validity and responsiveness of the PDAS, including HAMD-6 and BPRS-5, were acceptable, with the exception of the clinical responsiveness of the PDAS for positive symptoms and the clinical responsiveness of BPRS-5 for negative symptoms.

CONCLUSION

The clinical relevance of the PDAS has been confirmed and this clinical validation will enhance its clinical utility and availability.

Memory performance of patients with major depression in an everyday life situation

Although patients with major depressive disorder (MDD) report severe memory impairment in their everyday life, memory tests indicate only moderate deficits. In order to clarify these conflicting observations, the present study aimed at the investigation of MDD patients' memory performance in a real everyday life situation. The study included 20 MDD patients and 20 healthy control subjects. Nonverbal memory was assessed by means of the Rey Complex Figure Test whereas verbal memory was assessed by the recall of a 20-item wordlist with supermarket products. For the assessment of everyday life memory, subjects had to purchase as many products as possible of the 20-item wordlist in a real supermarket. Furthermore, subjects were asked for memory complaints. MDD patients' performance in the supermarket resembled memory test results and was not significantly impaired. MDD patients' self-reports, however, indicated severe memory problems that clearly fell below their performance in the supermarket. This study helped to identify everyday life-related factors that do not impair MDD patients' cognitive performance beyond their performance in standard laboratory testing situations. These factors may not be relevant for remediation programs that are specifically developed for depressed patients.

Are major depression and bipolar disorder neuropsychologically distinct? A meta-analysis of comparative studies

BACKGROUND

Neuropsychological deficits are present in both major depression and bipolar disorder. So far, however, reports directly comparing these mood disorders with regard to cognitive outcomes have been scant and yielded inconsistent results. This work aims to combine the findings of comparative studies of cognition in major depression and bipolar disorder in order to explore whether these neuropsychiatric conditions present with distinct cognitive features.

METHODS

The main online databases were extensively searched to retrieve reports assessing neurocognitive functioning in two groups of mood disorder patients, one with major depressive disorder and another with bipolar disorder, both in the same phase of illness. Between-group effect sizes for cognitive variables were obtained from selected studies and pooled by means of meta-analytic procedures.

RESULTS

During euthymia, a significant overall effect size (Hedges'g=0.64, P<0.001) favoring major depressive disorder was found for verbal memory as assessed with list learning tests, whereas no significant between-group differences were found for the remaining variables analyzed. During depressive episodes, similar cognitive outcomes were observed between groups.

CONCLUSION

At present, it is not possible to postulate specific neuropsychological profiles for major depression and bipolar disorder in light of available evidence. It remains to be ascertained whether the differences found for verbal memory constitute an expression of distinct underlying mechanisms or whether they are best explained by sample characteristics or differential exposure to variables with a negative impact on cognition.

Dissection of major depressive disorder using polygenic risk scores for schizophrenia in two independent cohorts

Major depressive disorder (MDD) is known for its substantial clinical and suspected causal heterogeneity. It is characterized by low mood, psychomotor slowing and increased levels of the personality trait neuroticism; factors also associated with schizophrenia (SCZ). It is possible that some cases of MDD may have a substantial genetic loading for SCZ. The presence of SCZ-like MDD subgroups would be indicated by an interaction between MDD status and polygenic risk of SCZ on cognitive, personality and mood measures. Here, we hypothesized that higher SCZ polygenic risk would define larger MDD case-control differences in cognitive ability, and smaller differences in distress and neuroticism. Polygenic risk scores (PRSs) for SCZ and their association with cognitive variables, neuroticism, mood and psychological distress were estimated in a large population-based cohort (Generation Scotland: Scottish Family Health Study, GS:SFHS). The individuals were divided into those with, and without, depression (n=2587 and n=16 764, respectively) to test for the interactions between MDD status and schizophrenia risk. Replication was sought in UK Biobank (UKB; n=6049 and n=27 476 cases and controls, respectively). In both the cohorts, we found significant interactions between SCZ-PRS and MDD status for measures of psychological distress (βGS=-0.04, PGS=0.014 and βUKB=-0.09, PUKB⩽0.001 for GS:SFHS and UKB, respectively) and neuroticism (βGS=-0.04, PGS=0.002 and βUKB=-0.06, PUKB=0.023). In both the cohorts, there was a reduction of case-control differences on a background of higher genetic risk of SCZ. These findings suggest that depression on a background of high genetic risk for SCZ may show attenuated associations with distress and neuroticism. This may represent a causally distinct form of MDD more closely related to SCZ.

Anterograde Amnesia during Electroconvulsive Therapy: A Prospective Pilot-Study in Patients with Major Depressive Disorder

Electroconvulsive therapy (ECT) is considered an effective treatment for major depression with melancholic features. However, neurocognitive side-effects such as anterograde amnesia still regularly occur. The present study aims to evaluate the severity and course of anterograde amnesia in severely depressed patients undergoing ECT. In a prospective naturalistic study, anterograde memory function was assessed among inpatients who underwent ECT (n = 11). Subjects met DSM-IV criteria for major depressive disorder. Recruitment took place between March 2010-March 2011 and March 2012-March 2013. Controls treated with antidepressants (n = 9) were matched for age, gender and depression severity. Primary outcome measure was immediate recall; secondary outcome measures were delayed recall, recognition, and visual association. Differences were tested using repeated measures ANOVA and paired t-tests. Correlations with hypothesized covariates were calculated. In patients with major depressive disorder, ECT had a significant effect on delayed memory function (p<0.01 with large effect sizes). Findings on immediate recall were less consistent. Four weeks after treatment discontinuation, these memory functions had recovered. Age was identified as a very important covariate. The main limitations of our study are its naturalistic design, possibly compromising internal validity, and its small sample size. However, if these findings can be reproduced in a more comprehensive study group, then the possible induction of anterograde amnesia is not a justifiable reason for clinicians to disregard ECT as a treatment option.

Major depressive disorder

Major depressive disorder (MDD) is a debilitating disease that is characterized by depressed mood, diminished interests, impaired cognitive function and vegetative symptoms, such as disturbed sleep or appetite. MDD occurs about twice as often in women than it does in men and affects one in six adults in their lifetime. The aetiology of MDD is multifactorial and its heritability is estimated to be approximately 35%. In addition, environmental factors, such as sexual, physical or emotional abuse during childhood, are strongly associated with the risk of developing MDD. No established mechanism can explain all aspects of the disease. However, MDD is associated with alterations in regional brain volumes, particularly the hippocampus, and with functional changes in brain circuits, such as the cognitive control network and the affective-salience network. Furthermore, disturbances in the main neurobiological stress-responsive systems, including the hypothalamic-pituitary-adrenal axis and the immune system, occur in MDD. Management primarily comprises psychotherapy and pharmacological treatment. For treatment-resistant patients who have not responded to several augmentation or combination treatment attempts, electroconvulsive therapy is the treatment with the best empirical evidence. In this Primer, we provide an overview of the current evidence of MDD, including its epidemiology, aetiology, pathophysiology, diagnosis and treatment.

A meta-analysis of cognitive performance in melancholic versus non-melancholic unipolar depression

BACKGROUND

Recently there is increasing recognition of cognitive dysfunction as a core feature of Major Depressive Disorder (MDD). The goal of the current meta-analysis was to review and examine in detail the specific features of cognitive dysfunction in Melancholic (MEL) versus Non-Melancholic (NMEL) MDD.

METHODS

An electronic literature search was performed to find studies comparing cognitive performance in MEL versus NMEL. A meta-analysis of broad cognitive domains (processing speed, reasoning/problem solving, verbal learning, visual learning, attention/working memory) was conducted on all included studies (n=9). Sensitivity and meta-regression analyses were also conducted to detect possible effects of moderator variables (age, gender, education, symptom severity and presence of treatments).

RESULTS

MEL patients were older and more severly depressed than NMEL subjects. The MEL group was characterized by a worse cognitive performance in attention/working memory (ES=-0.31), visual learning (ES=-0.35) and reasoning/problem solving (ES=-0.46). No difference was detected in drug-free patients by sensitivity analyses. No effect was found for any of our moderators on the cognitive performance in MEL vs NMEL.

CONCLUSION

Our findings seem to support a moderate but specific effect of melancholic features in affecting the cognitive performance of MDD, in particular as regards visual learning and executive functions.

Theory of mind in major depressive disorder: A meta-analysis

OBJECTIVE

Social cognitive deficits can contribute to risk for depression and to psychosocial impairment during depression. However, available evidence suggests that emotion recognition is only marginally impaired in major depressive disorder (MDD). Recent studies have investigated theory of mind (ToM) abilities, a cognitively more demanding aspect of social cognition.

METHODS

We conducted a meta-analysis of studies comparing ToM abilities in MDD and healthy controls. 18 studies comparing 613 patients with MDD and 529 healthy controls were included.

RESULTS

MDD patients significantly underperformed healthy controls in ToM (d=0.51-0.58). ToM impairment in MDD was evident in response to different types of ToM tasks (verbal/visual and cognitive/affective and reasoning/decoding). ToM impairment was significantly related to severity of depressive symptoms.

CONCLUSION

Theory of mind abilities are impaired during depression and can potentially contribute to psychosocial difficulties during depression. There is a need to investigate ToM abilities in different subtypes and stages of depression, especially in remitted patients.

Cognitive Deficits as a Mediator of Poor Occupational Function in Remitted Major Depressive Disorder Patients

Cognitive deficits in major depressive disorder (MDD) patients have been described in numerous studies. However, few reports have aimed to describe cognitive deficits in the remitted state of MDD and the mediational effect of cognitive deficits on occupational outcome. The aim of the current review is to synthesize the literature on the mediating and moderating effects of specific domains of cognition on occupational impairment among people with remitted MDD. In addition, predictors of cognitive deficits found to be vocationally important will be examined. Upon examination of the extant literature, attention, executive function and verbal memory are areas of consistent impairment in remitted MDD patients. Cognitive domains shown to have considerable impact on vocational functioning include deficits in memory, attention, learning and executive function. Factors that adversely affect cognitive function related to occupational accommodation include higher age, late age at onset, residual depressive symptoms, history of melancholic/psychotic depression, and physical/psychiatric comorbidity, whereas higher levels of education showed a protective effect against cognitive deficit. Cognitive deficits are a principal mediator of occupational impairment in remitted MDD patients. Therapeutic interventions specifically targeting cognitive deficits in MDD are needed, even in the remitted state, to improve functional recovery, especially in patients who have a higher risk of cognitive deficit.

Pathogenetic and therapeutic applications of microRNAs in major depressive disorder

As a class of noncoding RNAs, microRNAs (miRNAs) regulate gene expression by inhibiting translation of messenger RNAs. These miRNAs have been shown to play a critical role in higher brain functioning and actively participate in synaptic plasticity. Pre-clinical evidence demonstrates that expression of miRNAs is differentially altered during stress. On the other hand, depressed individuals show marked changes in miRNA expression in brain. MiRNAs are also target of antidepressants and electroconvulsive therapy. Moreover, these miRNAs are present in circulating blood and can be easily detected. Profiling of miRNAs in blood plasma/serum provides evidence that determination of miRNAs in blood can be used as possible diagnostic and therapeutic tool. In this review article, these aspects are critically reviewed and the role of miRNAs in possible etiopathogenesis and therapeutic implications in the context of major depressive disorder is discussed.

Gender Differences in the Clinical Characteristics of Psychotic Depression: Results from the CRESCEND Study

OBJECTIVE

To test whether there are gender differences in the clinical characteristics of patients with psychotic depression (PD).

METHODS

Using data from the Clinical Research Center for Depression (CRESCEND) study in South Korea, we tested for potential gender differences in clinical characteristics among 53 patients with PD. The Psychotic Depression Assessment Scale (PDAS) and other psychometric scales were used to evaluate various clinical features of the study subjects. Independent t-tests were performed for normally distributed variables, Mann-Whitney U-tests for non-normally distributed variables, and χ(2)tests for discrete variables. In addition, to exclude the effects of confounding variables, we carried out an analysis of covariance (ANCOVA) for the normally distributed variables and binary logistic regression analyses for discrete variables, after adjusting the effects of marital status.

RESULTS

We identified more prevalent suicidal ideation (adjusted odds ratio [aOR]=10.316, p=0.036) and hallucinatory behavior (aOR=8.332, p=0.016), as well as more severe anxiety symptoms (degrees of freedom [df]=1, F=6.123, p=0.017), and poorer social and occupational functioning (df=1, F=6.265, p=0.016) in the male patients compared to the female patients.

CONCLUSION

Our findings suggest that in South Korean patients with PD, suicidal ideation, hallucinatory behavior, and anxiety is more pronounced among males than females. This should be taken into consideration in clinical practice.

A new perspective on the role of the CREB family of transcription factors in memory consolidation via adult hippocampal neurogenesis

Adult neurogenesis is the process by which new neurons are generated in the brains of adults. Since its discovery 50 years ago, adult neurogenesis has been widely studied in the mammalian brain and has provided a new perspective on the pathophysiology of many psychiatric and neurodegenerative disorders, some of which affect memory. In this regard, adult hippocampal neurogenesis (AHN), which occurs in the subgranular zone (SGZ) of the dentate gyrus (DG), has been suggested to play a role in the formation and consolidation of new memories. This process involves many transcription factors, of which cyclic AMP (cAMP)-responsive element-binding protein (CREB) is a well-documented one. In the developing brain, CREB regulates crucial cell stages (e.g., proliferation, differentiation, and survival), and in the adult brain, it participates in neuronal plasticity, learning, and memory. In addition, new evidence supports the hypothesis that CREB may also participate in learning and memory through its involvement in AHN. This review examines the CREB family of transcription factors, including the different members and known signaling pathways. It highlights the role of CREB as a modulator of AHN, which could underlie its function in memory consolidation mechanisms.