Verbal learning and memory in depression: a 9-year follow-up study

Efficacy and safety of esketamine versus propofol in electroconvulsive therapy for treatment-resistant depression: A randomized, double-blind, controlled, non-inferiority trial

BACKGROUND

Electroconvulsive therapy (ECT) is a commonly used alternative for treatment-resistant depression (TRD). Although esketamine has a rapid pharmacological antidepressant action, it has not been studied as an ECT anesthetic. The objective of this study was to compare the efficacy and safety of esketamine with propofol when both are used as ECT anesthetic agents.

METHODS

Forty patients with TRD were assigned to one of two arms in a double-blind, randomized controlled trial: esketamine or propofol anesthesia for a series of eight ECT sessions. Using a non-inferiority design, the primary outcome was the reduction in HAMD-17 depressive symptoms. The other outcomes were: rates of response and remission, anxiety, suicidal ideation, cognitive function, and adverse events. These were compared in an intention-to-treat analysis.

RESULTS

Esketamine-ECT was non-inferior to propofol-ECT for reducing TRD symptoms after 8 sessions (adjusted Δ = 2.0, 95 % CI: -1.2-5.1). Compared to propofol-ECT, esketamine-ECT also had higher depression response (80 % vs. 70 %; p = .06) and remission (65 % vs. 55 %; p = .11) rates but non-inferiority was not established. In four components of cognitive function (speed of processing, working memory, visual learning, and verbal learning) esketamine-ECT was non-inferior to propofol-ECT. The results for anxiety, suicidal ideation, and adverse events (all p's > .05) were inconclusive.

CONCLUSION

Esketamine was non-inferior to propofol when both are used as anesthetics for TRD patients undergoing ECT. Replication studies with larger samples are needed to examine the inconclusive results.

REGISTRATION NUMBER

ChiCTR2000033715.

Change in Cognitive Function over the Course of Major Depressive Disorder: A Systematic Review and Meta-analysis

Major depressive disorder (MDD) is associated with significant cognitive deficits during the acute and remitted stages. The aim of this systematic review and meta-analysis was to examine the course of cognitive function whilst considering demographic, treatment, or clinical features of MDD that could moderate the extent of cognitive change. Databases were searched to identify studies that reported on cognitive function in MDD with a ≥12-week test-retest interval. Relevant studies were pooled using random effects modelling to generate an inverse-variance, weighted, mean effect size estimate (Hedges' g) of cognitive change for each cognitive variable and for an overall composite cognitive domain. Of 6898 records, 99 eligible studies were identified from which 69 were meta-analysed, consisting of 4639 MDD patients (agemean = 40.25 years, female% = 64.62%) across 44 cognitive variables. In over 95% of cognitive variables, improvements were either of non-significant, negligible, or of a small magnitude, and when compared to matched healthy controls, the possibility of practice effects could not be precluded. Depressive symptom improvement and the number of previous depressive episodes moderated the extent of cognitive change, demonstrating state- and scar-like features for one-quarter of the cognitive domains. Further longitudinal studies are required to elucidate the MDD cognitive trajectory from initial onset. Findings nonetheless suggest that following pharmacological and non-pharmacological treatment, cognitive change in MDD is typically small, but the capacity for change may be less with episode recurrence. Targeting cognition early in the course of illness may facilitate better prognosis and support a more complete functional recovery.

Short-term cognitive effects of repeated-dose esketamine in adolescents with major depressive disorder and suicidal ideation: a randomized controlled trial

BACKGROUND

Ketamine and its enantiomer have rapid and robust effects on depressive symptom and suicidal ideation. Little is known about their cognitive effects in adolescents. We aimed to evaluate the short-term effect of esketamine on cognition in adolescents with major depressive disorder (MDD) and suicidal ideation.

METHOD

In this randomized-controlled trial, 51 participants aged 13-18 with MDD and suicidal ideation received three intravenous infusions of either esketamine (0.25 mg/kg) or midazolam (0.02 mg/kg). Four dimensions of the MATRICS Consensus Cognitive Battery (MCCB), including processing speed, working memory, verbal learning and visual learning, were assessed at Days 0, 6 and 12.

RESULTS

In the linear mixed model, a significant time main effect (F = 12.803, P < 0.001), drug main effect (F = 6.607, P = 0.013), and interaction effect (F = 3.315, P = 0.041) was found in processing speed. Other dimensions including working memory and verbal learning showed significant time main effect (all P < 0.05), but no significant drug or interaction effect (all P > 0.05). Esketamine group showed improvement in processing speed from baseline to Days 6 and 12, and working memory from baseline to Day 12 (all P < 0.05). The generalized estimation equation showed no significant association between baseline cognition and antidepressant or antisuicidal effect (both P > 0.05).

CONCLUSIONS

The present study suggested that three-dose subanesthetic esketamine infusions did not harm cognition among adolescents with MDD and suicidal ideation. Instead, esketamine may be associated with improvement in processing speed.

TRIAL REGISTRATION

This trial was registered in the Chinese Clinical Trials Registry ( http://www.chictr.org.cn , ChiCTR2000041232).

The association between overweight/obesity and poor cognitive function is mediated by inflammation in patients with major depressive disorder

BACKGROUND

Cognitive dysfunction is a common and core feature of major depressive disorder (MDD). Evidences exerted a potentially harmful role of obesity and higher peripheral levels of inflammation in cognitive function, but few studies have explored whether markers of peripheral inflammation might mediate the association between overweight/obesity and deficits in cognitive function. Our study aimed to examine the cognitive function in MDD patients and clarify the effects of overweight/obesity and inflammatory cytokines on cognitive dysfunction in this population.

METHOD

We used a cross-sectional design in this study. A total of 265 patients with MDD were enrolled and divided into underweight, normal weight and overweight/obese groups. The MATRICS Consensus Cognitive Battery (MCCB) was administered to measure the cognition. Plasma levels of nineteen cytokines were measured using high sensitivity multiplex bead-based assays.

RESULTS

We found overweight/obese MDD patients associated with higher plasma levels of tumor necrosis factor (TNF)-α, interleukin (IL)-8, and macrophage inflammatory protein (MIP)-1β and worse performance in speed of processing and working memory. The mediation analysis found higher levels of IL-8 (direct: β = -0.591 (95 % Confidence Interval (CI): -1.0 to -0.2), P = 0.002; indirect: β = 0.060 (95 % CI.: 0.0-0.2), P = 0.032) and TNF-α (direct: β = -0.589 (95 % CI.: -1.0 to -0.2), P = 0.002; indirect: β = 0.059 (95 % CI.: 0.1-0.2), P = 0.037) were associated with more deficits in speed of processing, and partially mediated the relationship between body mass index and speed of processing.

CONCLUSION

Our results suggest that elevated inflammation might be one biological mechanism underlying the link between higher body mass and deficits in processing speed in patients with MDD.

The effectiveness of repeated intravenous ketamine on subjective and objective psychosocial function in patients with treatment-resistant depression and suicidal ideation

BACKGROUND

Ketamine has rapid and robust antidepressant effects in adults with treatment-resistant depression (TRD), while its effects on functional outcomes have not been sufficiently evaluated. The aim was to evaluate the efficacy of ketamine treatment on both subjective and objective functioning, and to explore whether improvements in depressive symptom and cognition mediated changes in functioning.

METHODS

Adults (n=111) with TRD and/or suicidality received six infusions of ketamine (0.5mg/kg, thrice-weekly). Depression symptoms were assessed with the Montgomery-Asberg Depression Rating Scale (MADRS) at baseline, day 13 and day 26. Cognitive domains, including processing speed, working memory, visual learning and verbal learning were measured with the MATRICS Consensus Cognitive Battery, and subjective and objective functioning were measured with the Sheehan Disability Scale (SDS) and the Global Assessment of Functioning (GAF) at the same time-points.

RESULTS

Significant improvement was observed in SDS total score (effect size [ES]=-1.563) and GAF score (ES=1.700) during the 26-day observation. Results from path analysis indicated that reductions of the total MADRS score and improvements in processing speed aggregately significantly mediated the reductions of SDS total score (total indirect effect coef=-3.993, 95%CI [-4.9, -3.2], direct effect coef=-1.374, 95%CI [-2.4, -0.4]) as well as the increases of GAF score (total indirect effect coef=6.022, 95%CI [4.5, 7.8], direct effect coef=3.987, 95%CI [2.1, 5.8]).

CONCLUSION

Six infusions of ketamine was associated with improvements in functional outcomes in adults with TRD and/or suicidality. Depressive symptoms severity and processing speed performance were significant partial mediators of objective and subjective functioning improvements.

The potential pro-cognitive effects with intravenous subanesthetic ketamine in adults with treatment-resistant major depressive or bipolar disorders and suicidality

BACKGROUND

Ketamine has rapid and robust antidepressant effects in depression, while its effects on cognitive measures are less clearly understood. This aim of the study herein is to determine whether ketamine has direct pro-cognitive effects in real-world treatment depression and/or suicidality.

METHODS

Subjects with unipolar (n = 84) and bipolar (n = 27) depression suffering treatment resistance or suicidality received six infusions of ketamine (0.5 mg/kg) during a 12-day period. Depression symptoms were assessed using the Montgomery-Asberg Depression Rating Scale at baseline, day 13 and day 26. Cognitive domains, including processing speed, working memory, visual learning and verbal learning were also measured using the MATRICS Consensus Cognitive Battery at the same time-points.

RESULTS

Significant improvement was observed in processing speed at day 13 (effect size [ES] = 0.501) and day 26 (ES = 0.654), and verbal learning at day 13 (ES = 0.362). Path analysis showed significant direct (β = 2.444, P = 0.017) and indirect (β = 1.220, P = 0.048) effect of ketamine on processing speed, indicating its improvement was partly independent of improvement in depressive symptoms. The direct effect (β = -1.963, P = 0.052) of ketamine on verbal learning was not significant, whereas the indirect effect (β = 1.386, P = 0.024) was significant, indicating treatment with ketamine indirectly improved verbal learning performance, via changes in depressive symptom.

CONCLUSION

Six infusions of ketamine have a potential mood independent pro-cognitive effect on processing speed in adults with treatment depression and/or suicidality. The potential pro-cognitive effects of ketamine provide the basis for hypothesizing that other clinical outcomes (e.g., suicidality, functional impairment) reported with ketamine treatment may be in part mediated by improvement in cognition.

Clinical Quest for Associated Cognitive Impairment in Major Depressed Patients

Patients diagnosed with unipolar disorder usually experience impaired cognitive functioning during an acute depressive episode. The purpose of the current study was to investigate the association of specific clinical factors with cognitive dysfunction in a group of major depressed patients. 65 subjects diagnosed with recurrent major depressive disorder were evaluated during an acute episode. The cognitive functions were assessed with neuropsychological tests for attention and processing speed, memory, verbal fluency, psychomotor speed and executive functions. Hamilton Depression Rating Scale - 17 items was used to quantify the severity of depression. Clinical variables consisted in age at onset, number of previous depressive episodes, presence of psychotic symptoms or suicide attempts. The group had a mean age of 48.48 years, with predominance of females, with a history of 5.43 episodes and associated psychotic symptoms (23.1%) and suicide attempts (20%). Cognitive domains for which we found significant results (p < 0.05) were executive functions and attention, being associated with the number of previous depressive episodes. Psychomotor speed was significantly associated with the severity of depression. Also, patients with psychotic symptoms obtained altered results for psychomotor speed and verbal memory. For almost all cognitive domains we found significant statistical association with different clinical aspects, such as number of depressive episodes, severity of depression, presence of psychotic symptoms and suicide attempts. Since each of them had an influence over cognition, further studies involving larger samples are necessary to establish if there is a direct relationship between cognitive impairment and clinical variables.

Neurocognitive performance and repeated-dose intravenous ketamine in major depressive disorder

OBJECTIVE

Ketamine has demonstrated a rapid antidepressant and antisuicidal effect in patients with major depressive disorder (MDD), but the neurocognitive effects of ketamine are relatively unknown. This study aims to examine the neurocognitive effects of six ketamine infusions and the association of baseline neurocognitive function and the change in severity of depressive symptoms after the last infusions.

METHODS

Sixty-four patients with MDD completed six intravenous infusions of ketamine (0.5 mg/kg over 40 min) administered over a 12-day period (Monday-Wednesday-Friday), and were followed by a 2-week observational period. Four domains of neurocognitive function (including speed of processing, working memory, visual learning and verbal learning) were assessed using the MATRICS Consensus Cognitive Battery (MCCB) at 0, 13 and 26 days.

RESULTS

In linear mixed model, significant improvements were found in terms of speed of processing (F = 20.7, p < 0.001) and verbal learning (F = 11.1, p < 0.001). The Sobel test showed the improvement of speed of processing (Sobel test = 2.8, p < 0.001) and verbal learning (Sobel test = 3.6, p < 0.001) were significantly mediated by change in depressive symptoms. Other two neurocognitive domains showed no significant changes over time. Correlation analysis showed no significant association of change in depressive symptoms with neurocognitive function at baseline.

CONCLUSION

Our findings suggest that six ketamine infusions were associated with the improvement of speed of processing and verbal learning, which were partly accounted for by improvement in the severity of depression symptoms over time.

Cross-sectional relationship between kynurenine pathway metabolites and cognitive function in major depressive disorder

OBJECTIVE

Cognitive impairment is common among patients with major depressive disorder (MDD), but its pathological mechanism is complex and not fully understood. Evidence suggests that the kynurenine (KYN) pathway may be implicated in the pathophysiology of depression, but few studies have explored the association between the KYN pathway and cognitive impairment in MDD. Our aim was to examine the relationship between cognitive impairment and KYN pathway metabolites in patients with MDD.

METHODS

A total of 146 patients with MDD according to DSM-V and 72 healthy controls (HCs) were enrolled, and the severity of depressive symptoms using the 17-item Hamilton Depression Rating Scale (HAMD-17) and cognitive performance including speed of processing, working memory, visual learning and verbal learning were assessed. Blood samples were collected, and serum concentrations of tryptophan (TRP), kynurenine (KYN) and kynurenic acid (KYNA) were measured by liquid chromatography-tandem mass spectrometry.

RESULTS

In females with MDD, there was a significant negative association between the KYN level and verbal learning (B=-0.039, adjusted p = 0.018), and the KYN/TRP ratio was negatively correlated with speed of processing (B=-470.086, adjusted p = 0.029), verbal learning (B=-544.251, adjusted p = 0.002) and visual learning (B=-513.777, adjusted p = 0.004). Those associations were not present in male individuals with MDD or in HCs, except for a significant negative correlation between the KYNA/KYN ratio and category fluency (B=-0.373, adjusted p = 0.039) in female HCs.

CONCLUSION

Our results suggest that learning function and speed of processing in female MDD were associated with KYN serum level and the KYN/TRP ratio, potentially implicating the KYN pathway in the pathological mechanism of cognitive function in female MDD.

Cortisol levels and cognitive profile in major depression: A comparison of currently and previously depressed patients

The association between depressive symptoms and elevated cortisol levels, and depression and cognitive functioning, has been less robust in outpatients with symptoms in the mild to moderate range. Furthermore, the association between elevated cortisol levels and cognitive functioning is unclear. In the present study, currently depressed (n = 37), previously depressed (n = 81) and never depressed controls (n = 50) were assessed on a range of neuropsychological measures. Salivary cortisol was measured in the morning and evening. Participants with current depression were non-hospitalized and had symptoms predominately in the mild to moderate range. Elevated salivary evening cortisol, but not morning cortisol, was significantly related to depressive symptoms. The difference in cortisol levels between the previously depressed group and the never depressed controls was not significant. The groups had significantly different cognitive profiles, with the currently depressed performing poorer on tasks related to working memory compared to the never depressed controls. Both the currently and previously depressed performed worse on attentional tasks. The findings indicate that outpatients with mild to moderate depression have elevated cortisol levels and limited mild cognitive impairments. Furthermore, mild impairments in attention may persist after remission, indicating that this could be a trait-marker in depression. The present study did not find support for a significant relationship between cortisol and cognitive functioning.

PsychotherapyPlus: augmentation of cognitive behavioral therapy (CBT) with prefrontal transcranial direct current stimulation (tDCS) in major depressive disorder-study design and methodology of a multicenter double-blind randomized placebo-controlled trial

Major Depressive Disorder (MDD) is one of the most prevalent psychiatric disorders worldwide. About 20-30% of patients do not respond to the standard psychopharmacological and/or psychotherapeutic interventions. Mounting evidence from neuroimaging studies in MDD patients reveal altered activation patterns in lateral prefrontal brain areas. Successful cognitive behavioral therapy (CBT) is associated with a recovery of these neural alterations. Moreover, it has been demonstrated that transcranial direct current stimulation (tDCS) is capable of influencing prefrontal cortex activity and cognitive functions such as working memory and emotion regulation. Thus, a clinical trial investigating the effects of an antidepressant intervention combining CBT with tDCS seems promising. The present study investigates the antidepressant efficacy of a combined CBT-tDCS intervention as compared to CBT with sham-tDCS or CBT alone. A total of 192 patients (age range 20-65 years) with MDD (Hamilton Depression Rating Scale Score ≥ 15, 21-item version) will be recruited at four study sites across Germany (Berlin, Munich, Tuebingen, and Freiburg) and randomly assigned to one of the following three treatment arms: (1) CBT + active tDCS; (2) CBT + sham-tDCS; and (3) CBT alone. All participants will attend a 6-week psychotherapeutic intervention comprising 12 sessions of CBT each lasting 100 min in a closed group setting. tDCS will be applied simultaneously with CBT. Active tDCS includes stimulation with an intensity of 2 mA for 30 min with the anode placed over F3 and the cathode over F4 according to the EEG 10-20 system, if assigned. The primary outcome measure is the change in Montgomery-Åsberg Depression Rating Scale scores from baseline to 6, 18, and 30 weeks after the first session. Participants also undergo pre- and post-treatment neuropsychological testing and functional magnetic resonance imaging (fMRI) to assess changes in prefrontal functioning and connectivity. The study investigates whether CBT can be augmented by non-invasive brain stimulation techniques such as tDCS in the treatment of MDD. It is designed as a proof-of-principle trial for the combined tDCS-CBT treatment, but also allows the investigation of the neurobiological underpinnings of the interaction between both interventions in MDD. Trial registration ClinicalTrials.gov Identifier NCT02633449.

Diagnostic differences in verbal learning strategies and verbal memory in patients with mood disorders and psychotic disorders

A better understanding of verbal learning strategies can offer insight to the difference in verbal memory performance and learning between patients with schizophrenia and schizoaffective disorders, non-psychotic major depression, and psychotic major depression. To date, a comparison of the use of verbal learning strategies and verbal memory performance amongst these specific diagnostic groups has not been investigated. This study examined differences in verbal learning and memory between psychotic major depression (n = 31), nonpsychotic major depression (n = 30), and schizophrenia spectrum disorders (n = 17) disorders. Verbal learning and memory were assessed through the use of the California Verbal Learning Test-II (CVLT-II). Correlations and multiple regression analyses were conducted to analyze differences in verbal learning and memory amongst these groups. There were no significant differences in the use of Semantic Clustering. Diagnostic differences were observed in the use of Serial and Subjective Clustering. The psychotic major depression group utilized Serial Clustering strategy significantly less than the nonpsychotic major depression group. Learning strategies significantly predicted learning and recall. These findings lend support to the hypothesis that learning strategies predict verbal memory performance across diagnostic groups. The present study contains useful information on diagnostic differences in verbal learning and memory, and a framework by which treatment could be tailored to enhance learning specific to these diagnostic groups.

Neurocognitive effects of six ketamine infusions and the association with antidepressant response in patients with unipolar and bipolar depression

BACKGROUND

Ketamine has proven to have rapid, robust antidepressant effects on treatment-resistant depression. However, whether repeated ketamine infusions would cause short-and long-term neurocognitive impairments was not clear. Our aims were to investigate the neurocognitive effects of six ketamine infusions and to examine the association between these infusions and the antidepressant response in patients with unipolar and bipolar depression.

METHODS

Six intravenous infusions of ketamine (0.5 mg/kg) over a 12-day period were administered to 84 patients with unipolar and bipolar depression. Severity of depressive symptoms and four domains of neurocognition, including speed of processing, working memory, visual learning and verbal learning, were assessed at baseline, one day following the last infusion and again two weeks post-infusion.

RESULTS

Significant improvements were found on speed of processing ( F=9.344, p<0.001) and verbal learning ( F=5.647, p=0.004) in a linear mixed model. The Sobel test showed significant indirect effects between time and improvement in speed of processing (Sobel test=3.573, p<0.001) as well as improvement in verbal learning (Sobel test=6.649, p<0.001), which were both significantly mediated by change in depressive symptoms. Logistic regression analysis showed ketamine responders had better visual learning at baseline than non-responders (B=0.118, p<0.001).

CONCLUSIONS

Our findings suggest that neurocognitive function would not deteriorate after six ketamine infusions, while verbal learning and speed of processing improved over 13 days and 26 days of observation, respectively. However, this change was mainly accounted for by improvements in severity of depressive symptoms over time. Greater baseline visual learning predicted an antidepressant response over six ketamine infusions.

No evidence in favor of a more deleterious impact of a major depressive episode on verbal memory in older patients with antidepressant response

BACKGROUND

Older patients may be more vulnerable to the deleterious effect of depressive episodes on delayed narrative memory, a cognitive task which reflects hippocampal activity. We aimed to disentangle which factors could explain such increased vulnerability in the elderly, including the poorer response to treatment, a longer lifetime exposure to past depressive episodes, and lower baseline memory skills.

METHODS

From an initial sample of 8,229 depressed outpatients, we focused on the 2,424 treatment responders, and compared older (65 years old and over, N = 233) to younger (N = 2,191) ones. These patients were included through general practitioners' assessment and tested for the Wechsler delayed paragraph recall index, a valid and sensitive test assessing verbal declarative memory (and a marker of the hippocampal function), at baseline and after six weeks of treatment.

RESULTS

As expected, older patients after response to antidepressants showed decreased narrative memory abilities compared to younger ones. As baseline memory performance and residual depressive symptoms were also found in excess in this sample, they could act as confounders. Indeed, after controlling for these two factors, the role of age in memory performance after treatment response was ruled out.

CONCLUSIONS

The potential "toxicity" of a depressive episode to cognitive functions related to the hippocampus may not be more critical in older patients compared to younger ones. Limiting remaining depressive symptoms in older depressed patients might be a way to counteract the observed worsening of memory functions in depressed patients.

The Effect of Self-Care Education on the Awareness, Attitude, and Adherence to Self-Care Behaviors in Hospitalized Patients Due to Heart Failure with and without Depression

Background

Cardiovascular diseases are among somatic disorders and psychological factors affect their onset, exacerbation, and treatment. This study was conducted on the hospitalized patients who had heart failure with and without depression. The study criteria was to evaluate the effect of self-care education on awareness, attitude, and adherence to self-care behaviors on these patients.

Materials and Methods

In this quasi-experimental study, seventy patients with heart failure that met the inclusion criteria were recruited through purposive sampling method. They were assigned in to two equal size groups regarding their depression status. First, the eligible patients were selected; then Beck Depression Inventory was done on the patients followed by examination by the clinical psychologist. Patients with average and higher scores were classified in the depressed group and others who got lower than average scores were classified as the non -depressed group. A questionnaire containing items related to awareness, attitude, and adherence to self-care behaviors was used to collect the data. First, self-care behavior was determined and then a four-sessions of educational intervention were held individually for both groups. The second round of questionnaires were completed at patients’ home twelve weeks after the discharge. The Collected data was analyzed using independent-samples and paired-sample t tests, Chi square, and statistical analysis of covariance (ANCOVA) tests through SPSS (version 21, SPSS Inc., Chicago, IL, USA).

Results

After the educational sessions, the statistical analysis showed significant differences in the mean scores of awareness, attitude, and adherence to self-care behaviors between the two groups (P<0.0001).

Conclusion

Self-care behavior education had lower effects on the depressed patients with heart failure. Therefore, before providing education for these patients, it is necessary to consider their psychological problems such as depression.

Tryptophan hydroxylase 2 gene is associated with cognition in late-onset depression in a Chinese Han population

Accumulating evidences suggest that Tryptophan hydroxylase 2 (TPH2) gene is associated with major depressive disorder (MDD) and cognitive function. In present study, we aimed to explore the association of cognitive disturbances in patients with late-onset depression (LOD) in the Chinese Han population. One hundred and ninety unrelated LOD patients who met DSM-IV criteria for major depressive disorder were recruited for the study and 155 normal controls were recruited from local community. All subjects completed the demographic assessments. Furthermore, 97 patients and 44 controls completed a series of neuropsychological tests. Patients and normal controls were genotyped for TPH2 (rs4290270 and rs7305115) variants using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The results of our analysis indicated no significant differences in the frequencies of the single alleles and genotypes of two polymorphisms in TPH2 gene between LOD patients and normal controls. Haplotype association indicated that no differences were found in the frequencies of haplotype between two groups. A significant main effect of rs4290270 genotype on Verbal Fluency Test (VFT) test performance was found (P<0.05). There was a significant interactive effect of rs7305115 polymorphisms and depression diagnosis on Symbol Digit Modalities Test (SDMT) (P<0.05). After controlling for covariates, the subjects with carriers of GG genotype in rs7305115 had more better SDMT performance compared to AG and AA carriers in LOD groups. The result suggests that there is a major effect of rs4290270 in TPH2 on cognitive function alone. Moreover, an interaction of rs7305115 polymorphisms and depression diagnosis may be associated with the cognitive function. Further studies in a large sample are needed to replicate the genetic role in the LOD patients.

[Verbal memory in patients with major depression]

INTRODUCTION

Patients with major depression commonly report memory deficits but studies on this topic have shown inconsistent results. The aim of this study was to determine whether patients with major depression showed any differences in explicit verbal memory compared to healthy controls.

MATERIAL AND METHODS

We used the California verbal learning test (CVLT) in order to compare the explicit verbal memory of 30 patients (21 women and 9 men) to a healthy control group (23 women and 10 men).

RESULTS

The results showed no significant differences between verbal memory performance of patients with major depression and healthy controls.

DISCUSSION

Verbal memory of depressive patients with antidepressant pharmacotherapy showed no significant differences compared to a healthy control group. It can be assumed that verbal memory in depression depends on variable parameters (e.g. age, severity and duration of depression and medication). More studies with a larger number of patients should be conducted to obtain reliable results about explicit verbal memory in depression.

Comparative study of cognitive impairment between medicated and medication-free patients with remitted major depression: class-specific influence by tricyclic antidepressants and newer antidepressants

Patients with major depressive disorder (MDD) are known to present with cognitive deficits; however, the presence of these deficits in the remitted state have been inconsistent. One of the most important factors potentially contributing to inconsistencies between studies may be the influence of medications. To explore the influence of antidepressants on cognitive performance in remitted MDD, we evaluated memory and executive functions using Wechsler Memory Scale-Revised and Stroop Color and Word Test, and compared performance among 50 medicated (29 treated with tricyclic antidepressants [TCA], 21 treated with selective serotonin reuptake inhibitors or serotonin noradrenalin reuptake inhibitors) and 19 medication-free MDD patients and 31 controls. The results showed that all 3 MDD groups had significantly lower performance for verbal memory compared with controls. Both medicated groups showed significantly lower performance for visual memory compared with controls; however, the medication-free group did not differ from controls. For the executive function, only the TCA group showed a significantly lower performance compared with controls. These results suggest that cognitive impairment remained even in remitted patients with MDD, however, part of this impairment may be influenced by class-specific antidepressant side effects.

Time course for memory dysfunction in early-life and late-life major depression: a longitudinal study from the Juntendo University Mood Disorder Project

BACKGROUND

Previous studies have demonstrated that patients with depression also have memory dysfunctions during depressive episodes. These dysfunctions partially remain immediately after remission from a depressive state; however, it is unclear whether these residual memory dysfunctions may disappear through long-term remission from depression. The present study compared patients during early-life (age<60) and late-life (age ≥ 60) depression while in their remitted stage with healthy controls to elucidate the impact of a long-term course on memory.

METHODS

Logical memory from the Wechsler Memory Scale-Revised was administered to 67 patients with major depressive disorder (MDD) (47 patients with early-life depression and residual 20 patients with late-life depression) and 50 healthy controls. MDD patients received memory assessments at the time of their initial remission and at a follow-up three years after remission.

RESULTS

At the time of initial remission, scores for logical memory were significantly lower in both patient groups compared to matched controls. At follow-up, memory dysfunction for early-life MDD patients disappeared, whereas scores in the late-life MDD group remained significantly lower than those of matched controls.

LIMITATIONS

All patients in the present study were on antidepressant medications.

CONCLUSIONS

Our findings suggested that the progress of memory performance in late-life MDD patients may be different from early-life MDD patients.

Invisible emotional expressions influence social judgments and pupillary responses of both depressed and non-depressed individuals

We used filtered low spatial frequency images of facial emotional expressions (angry, fearful, happy, sad, or neutral faces) that were blended with a high-frequency image of the same face but with a neutral facial expression, so as to obtain a “hybrid” face image that “masked” the subjective perception of its emotional expression. Participants were categorized in three groups of participants: healthy control participants (N = 49), recovered previously depressed (N = 79), and currently depressed individuals (N = 36), All participants were asked to rate how friendly the person in the picture looked. Simultaneously we recorded, by use of an infrared eye-tracker, their pupillary responses. We expected that depressed individuals (either currently or previously depressed) would show a negative bias and therefore rate the negative emotional faces, albeit the emotions being invisible, as more negative (i.e., less friendly) than the healthy controls would. Similarly, we expected that depressed individuals would overreact to the negative emotions and that this would result in greater dilations of the pupil's diameter than those shown by controls for the same emotions. Although we observed the expected pattern of effects of the hidden emotions on both ratings and pupillary changes, both responses did not differ significantly among the three groups of participants. The implications of this finding are discussed.

Cognitive function in unipolar major depression: a comparison of currently depressed, previously depressed, and never depressed individuals

There is a lack of consensus upon a conclusive cognitive profile characterizing unipolar major depression. Currently depressed (n = 37), recovered previously depressed (n = 81), and never depressed controls (n = 50) underwent assessment of executive functions, working memory, attention, and psychomotor speed. Currently depressed yielded significantly lower test scores than previously and never depressed subjects on a measure of working memory. Both currently depressed and previously depressed scored significantly lower than never depressed subjects on measures of processing speed. Recurrent depressed performed similarly to subjects with a single depressive episode. These findings indicate a mild and limited cognitive impairment during the course of a mild to moderate major depressive disorder among relatively young adults. Impaired processing speed should be considered in further studies as a potential irreversible marker for recurrent depression.