Cognition in major depressive disorder: a 'Systemically Important Functional Index' (SIFI)

Longitudinal bidirectional association between psychosocial function and depression in Chinese patients with clinically remitted depression: a cross-lagged panel model analysis

BACKGROUND

Major depressive disorder (MDD) imposes serious effect on patient's psychosocial function, which hinders the full recovery from the disease and increases the risk of recurrence, although the participants had achieved clinical remission. To understand the relationship between psychosocial function and depressive symptoms could facilitate recurrence prevention. Therefore, the purpose of this study was to analyze the relation among psychosocial function and BDI score in Chinese patients with clinically cured depression within 1 year follow-up.

METHODS

One hundred nineteen valid participants were assessed at baseline(t1), months 6(t2) and months 12(t3). Beck Depression Inventory-II (BDI-II) was used to assess depressive symptoms and indicate the possibility of depression level. Generic Quality of Life Inventory (GQOLI) was used to assessed the participants' psychosocial function(F), including body function (BF), psychological function (PF) and social function (SF). The application of a cross-lagged panel model (CLPM) approach revealed an association between BDI and psychosocial function.

RESULT

The CLPM results showed total average score of psychosocial function have reciprocal influence on BDI score. The model analyzed by structural equation modeling satisfied all indices of goodness-of-fit (chi-square = 10.306, TLI = 0.959, CFI = 0.988 RMSEA = 0.115). And body function, psychological function, social function and BDI score also affect each other. Depressive symptoms and psychosocial function could predict scores of each other 6 months later. By comparing standardized cross-lagged path, only social function has a more pronounced impact on depressive symptoms, since the absolute effect of SFt1 → BDIt2 is larger than that of BDIt1 → SFt2 (a1 vs. b1 = -.267, SE = .108, P < 0.05, 95%CI[-.485,-.063]) and the absolute effect of SFt2 → BDIt3 is larger than that of BDIt2 → SFt3 (a2 vs. b2 = -.317, SE = .096, P < 0.01,95%CI[-.508,-.129]).

CONCLUSION

The current study showed a significant bidirectional association between depressive level and psychosocial function, and the social function exerted more effect on the depression.

Using the THINC-integrated tool to compare the characteristics of cognitive dysfunction in patients with unipolar and bipolar depression

BACKGROUND

Major depressive disorder (MDD) and bipolar depression (BD-D) are both intricate, enduring, and profound psychiatric conditions characterized primarily by depressive episodes and cognitive dysfunction. However, distinguishing the characteristics and influencing factors of cognitive impairment in unipolar and BD-D is crucial for identification and intervention.

AIM

To compare neurocognitive characteristics and investigate associations between cognitive function and clinical features in unipolar and BD-D.

METHODS

The THINC-integrated tool (THINC-it) as a cognitive assessment tool was applied to 295 individuals: 75 patients with depressive disorders (MDD), 120 individuals with BD-D, and 100 healthy controls. The Hamilton Depression Scale-17 (HAMD), Hamilton Anxiety Scale-14 (HAMA), and Pittsburgh Sleep Quality Index (PSQI) were employed to assess depression, anxiety, and sleep. Neurocognitive function characteristics and the relationships between cognitive impairment and general clinical attributes were analyzed.

RESULTS

There were no statistically significant differences in the overall THINC-it with each objective subscale. However, the subjective subscale (Perceived Deficits Questionnaire for Depression-5-item) showed significant differences between MDD and BD-D (P < 0.001). Linear regression analyses were explored to determine associations. Age, years of education, age at onset, and HAMD were significantly co-associated with the overall THINC-it and each subscale in both MDD and BD-D (P < 0.05). Furthermore, years of education showed a positive correlation with objective cognitive impairment (e.g., Codebreaker, Trails) (P < 0.05). There was a notable difference in that the number of depressive episodes, disease duration, hospitalizations, HAMA, and PSQI were significantly associated with the overall THINC-it with each subscale between MDD and BD-D (P < 0.05).

CONCLUSION

Although both unipolar and BD-D showed similar objective cognitive impairments, there was a significant difference in subjective cognitive impairment. Our findings suggest that factors like age, years of education, age at onset, and depression severity might not be significantly difference in the influence of cognitive impairment. Furthermore, we found that education was a protective factor for cognitive impairment in both unipolar and BD-D. Our analysis revealed that distinct factors including disease duration, number of depressive episodes, hospitalizations, anxiety levels, and sleep quality influenced cognitive impairment between unipolar and BD-D. Therefore, it was important to investigate the specific characteristics of cognitive impairment and influencing factors to identify differentiating unipolar and BD-D.

Parsing the heterogeneity of depression: a data-driven subgroup derived from cognitive function

Background

Increasing evidences suggests that depression is a heterogeneous clinical syndrome. Cognitive deficits in depression are associated with poor psychosocial functioning and worse response to conventional antidepressants. However, a consistent profile of neurocognitive abnormalities in depression remains unclear.

Objective

We used data-driven parsing of cognitive performance to reveal subgroups present across depressed individuals and then investigate the change pattern of cognitive subgroups across the course in follow-up.

Method

We assessed cognition in 163 patients with depression using The Chinese Brief Cognitive Test(C-BCT) and the scores were compared with those of 196 healthy controls (HCs). 58 patients were reassessed after 8 weeks. We used K-means cluster analysis to identify cognitive subgroups, and compared clinical variables among these subgroups. A linear mixed-effects model, incorporating time and group (with interaction term: time × group) as fixed effects, was used to assess cognitive changes over time. Stepwise logistic regression analysis was conducted to identify risk factors associated with these subgroups.

Results

Two distinct neurocognitive subgroups were identified: (1) a cognitive-impaired subgroup with global impairment across all domains assessed by the C-BCT, and (2) a cognitive-preserved subgroup, exhibited intact cognitive function, with performance well within the healthy range. The cognitive-impaired subgroup presented with more severe baseline symptoms, including depressed mood, guilt, suicidality, and poorer work performance. Significant group × time interactions were observed in the Trail Making Test Part A (TMT-A) and Continuous Performance Test (CPT), but not in Symbol Coding or Digit Span tests. Despite partial improvement in TMT-A and CPT tests, the cognitive-impaired subgroup's scores remained lower than those of the cognitive-preserved subgroup across all tests at the study endpoint. Multiple regression analysis indicated that longer illness duration, lower educational levels, and antipsychotic medication use may be risk factors for cognitive impairment.

Conclusion

This study identifies distinguishable cognitive subgroups in acute depression, thereby confirming the presence of cognitive heterogeneity. The cognitive-impaired subgroup exhibits distinct symptoms and persistent cognitive deficits even after treatment. Screening for cognitive dysfunction may facilitate more targeted interventions.

Clinical Trial Registration

https://www.chictr.org, identifier ChiCTR2400092796.

The sex-specific relationship of ghrelin and cognition in Chinese han first-episode drug-naive major depressive disorder

In major depressive disorder (MDD), alterations in ghrelin levels and cognitive impairment coexist, yet their association has remained largely elusive. This study aimed to investigate the association between ghrelin levels and cognition in both MDD patients and healthy controls (HCs) while also exploring sex-specific differences in this correlation. A total of 155 Chinese Han subjects, including 90 first-episode drug-naive MDD patients and 65 HCs, were enrolled. Ghrelin levels were measured using ELISA kits, and neurocognitive assessments were conducted using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). MDD patients exhibited significantly higher ghrelin levels and lower cognitive scores of RBANS compared to HCs. However, there was no significant correlation between ghrelin levels and cognitive function in both MDD patients and HCs. Exploratory analyses revealed sex-specific associations between ghrelin and cognitive function, particularly in MDD patients. Females with MDD showed distinct patterns of association between ghrelin levels and cognitive domains such as attention and language, which were not observed in healthy controls or male MDD patients. The relationship between ghrelin and cognition only existed in MDD patients, not in the HCs, and there was a sex-specific difference in this association. Further research on the mechanism of ghrelin in the cognitive function of MDD should focus on sex differences.

Impact of trazodone once-a-day on quality of life and functional recovery in adults with major depressive disorder: A prospective, observational study

BACKGROUND

Health-related quality of life (HRQL) is an important goal for patients with major depressive disorder (MDD), but whether antidepressants improve HRQL in these patients is unclear. Here, we describe the real-world effects of trazodone once-a-day (TzOAD) and selective serotonin reuptake inhibitor (SSRI) treatments on HRQL and functioning in adults with MDD.

METHODS

This 8-week prospective, observational, open-label, multicenter study was conducted in adults with moderate or severe MDD for whom TzOAD or SSRI were prescribed as monotherapy. The primary outcome was life enjoyment and satisfaction assessed via the patient-reported Quality-of-Life Enjoyment and Satisfaction Questionnaire Short Form (Q-LES-Q-SF) from baseline to week 8. Secondary outcomes included change in Q-LES-Q-SF from baseline to weeks 1 and 2; severity of depressive symptoms using the Montgomery Åsberg Depression Rating Scale (MADRS) and sleep disturbance via the PROMIS SF-SD 8b questionnaire at weeks 1, 2, and 8; and overall functioning via the Sheehan Disability Scale (SDS), hedonic capacity using the Snaith-Hamilton Pleasure Scale (SHAPS), and cognitive dysfunction using the Perceived Deficits Questionnaire (PDQ-5) at baseline and week 8.

RESULTS

The study included 208 adults with MDD (mean [SD] age = 50.2 [14.3] years; 68.6% female; 98.4% White). Life enjoyment and satisfaction improved from baseline to week 8 for both treatment groups: Q-LES-Q-SF mean (SD) scores were 27.5 (20.4) for the SSRI group and 39.0 (22.1) for the TzOAD group. Depressive symptoms and sleep disturbances also reduced from baseline to week 8: MADRS (SSRI, -15.7 [8.3]; TzOAD, -21.0 [9.8]); PROMIS SF-SD 8b (SSRI, -9.9 [12.6]; TzOAD, -22.0 [12.6]). Mean change scores in Q-LES-Q-SF, MADRS, and PROMIS SF-SD 8b improved as early as week 1 in both groups. Mean scores also improved from baseline to week 8 on SDS (SSRI, -9.2 [7.4]; TzOAD, -14.3 [7.5]), SHAPS (SSRI, -6.6 [4.3]; TzOAD, -8.3 [4.4]), and PDQ-5 (SSRI, -5.8 [4.5]; TzOAD, -7.7 [5.0]).

CONCLUSIONS

In adults with MDD who received TzOAD or SSRIs, overall and individual HQRL domains improved rapidly and in parallel with improvements in depressive symptoms, with a slightly greater improvement observed in the TzOAD group.

Factors associated with objective and subjective cognitive impairment in Chinese patients with acute major depressive disorder

BACKGROUND

Patients diagnosed withmajor depressive disorder (MDD) usually experience impaired cognitive functioning, which might negatively impact their clinical and functional outcomes. This study aimed to investigate the association of specific clinical factors with cognitive dysfunction in a group of MDD patients.

METHODS

A total of 75 subjects diagnosed with recurrent MDD were evaluated during the acute stage. Their cognitive functions were assessed using the THINC-integrated tool (THINC-it) for attention/alertness, processing speed, executive function, and working memory. Clinical psychiatric evaluations, such as the Hamilton Anxiety Scale (HAM-A), the Young Mania Rating Scale (YMRS), the Hamilton Depression Scale (HAM-D), and the Pittsburgh Sleep Quality Index(PSQI), were used to assess patients' levels of anxiety, depression and sleeping problems. The investigated clinical variables were age, years of education, age at onset, number of depressive episodes, disease duration, presence of depressive and anxiety symptoms, sleep problems, and number of hospitalizations.

RESULTS

The results revealed that significant differences were observed between the two groups in the THINC-it total scores, Spotter, Codebreaker, Trails, and PDQ-5-D scores (P < 0.001). The THINC-it total scores, Spotter, Codebreaker, Trails, and Symbol Check were significantly associated with age and age at onset(P < 0.01). In addition, regression analysis found that years of education was positively associated with the Codebreaker total scores (P < 0.05). the THINC-it total scores, Symbol Check, Trails, and Codebreaker were correlated with the HAM-D total scores(P < 0.05). Additionally, the THINC-it total scores, Symbol Check, PDQ-5-D and Codebreaker significantly correlated with the PSQI total scores (P < 0.05).

CONCLUSION

We found a significant statistical association between almost all cognitive domains and different clinical aspects in depressive disorder, such asage, age at onset, severity of depression, years of education, and sleep problems. Additionally, education was shown to be a protective factor against processing speed impairments. Special considerations of these factors might help outline better management strategies to improve cognitive functions in MDD patients.

Abnormal dynamic functional connectivity of hippocampal subregions associated with working memory impairment in melancholic depression

BACKGROUND

Previous studies have demonstrated structural and functional changes of the hippocampus in patients with major depressive disorder (MDD). However, no studies have analyzed the dynamic functional connectivity (dFC) of hippocampal subregions in melancholic MDD. We aimed to reveal the patterns for dFC variability in hippocampus subregions - including the bilateral rostral and caudal areas and its associations with cognitive impairment in melancholic MDD.

METHODS

Forty-two treatment-naive MDD patients with melancholic features and 55 demographically matched healthy controls were included. The sliding-window analysis was used to evaluate whole-brain dFC for each hippocampal subregions seed. We assessed between-group differences in the dFC variability values of each hippocampal subregion in the whole brain and cognitive performance on the MATRICS Consensus Cognitive Battery (MCCB). Finally, association analysis was conducted to investigate their relationships.

RESULTS

Patients with melancholic MDD showed decreased dFC variability between the left rostral hippocampus and left anterior lobe of cerebellum compared with healthy controls (voxel p < 0.005, cluster p < 0.0125, GRF corrected), and poorer cognitive scores in working memory, verbal learning, visual learning, and social cognition (all p < 0.05). Association analysis showed that working memory was positively correlated with the dFC variability values of the left rostral hippocampus-left anterior lobe of the cerebellum (r = 0.338, p = 0.029) in melancholic MDD.

CONCLUSIONS

These findings confirmed the distinct dynamic functional pathway of hippocampal subregions in patients with melancholic MDD, and suggested that the dysfunction of hippocampus-cerebellum connectivity may be underlying the neural substrate of working memory impairment in melancholic MDD.

Cognitive functioning as predictor and marker of response to repetitive transcranial magnetic stimulation in depressive disorders: A systematic review

OBJECTIVE

Cognitive performance in Major Depressive Disorder (MDD) is frequently impaired and related to functional outcomes. Repetitive Transcranial Magnetic Stimulation (rTMS) may exert its effects on MDD acting both on depressive symptoms and neurocognition. Furthermore, cognitive status could predict the therapeutic response of depressive symptoms to rTMS. However, cognitive performances as a predictor of rTMS response in MDD has not been thoroughly investigated. This review aims to evaluate the role of pre-treatment cognitive performance as a predictor of clinical response to rTMS, and the effects of rTMS on neurocognition in MDD.

METHOD

A systematic review of studies evaluating neurocognition in MDD as an outcome and/or predictor of response to rTMS was conducted using PubMed/Medline and Embase.

RESULTS

Fifty-eight articles were identified: 25 studies included neurocognition as a predictor of response to rTMS; 56 used cognitive evaluation as an outcome of rTMS. Baseline cognitive performance and cognitive improvements after rTMS predicted clinical response to rTMS. Moreover, rTMS improved cognition in MDD.

CONCLUSIONS

Cognitive assessment could predict improvement of depression in MDD patients undergoing rTMS and help selecting patients that could have beneficial effects from rTMS. A routine cognitive assessment might stratify MDD patients and track rTMS related cognitive improvement.

Association between baseline cognitive symptoms and the subsequent presenteeism and global function in patients with major depressive disorder

Cognitive symptoms in major depressive disorder (MDD) contribute to impaired functional abilities and work productivity, particularly presenteeism. We investigated the association between baseline cognitive symptoms and subsequent presenteeism, and global functional impairment in Japanese patients with MDD from PERFORM-J (Prospective Epidemiological Research on Functioning Outcomes Related to Major Depressive Disorder in Japan) - a 6-month, multicenter, epidemiological study data. A total of 518 patients initiating antidepressant monotherapy (first-line or switched from another drug) were enrolled. Assessments include Perceived Deficits Questionnaire - Depression (PDQ-D) for cognitive complaints, Sheehan Disability Scale (SDS) for global function (analysed n = 318), and Work Productivity and Activity Impairment Questionnaire for presenteeism (analysed n = 122). A strong association between changes in presenteeism and changes in SDS scores (r: total = 0.636; work/school = 0.686) was observed. After adjusting for sociodemographic and MDD-related factors, patients without cognitive complaints at baseline showed lower odds of impaired presenteeism at 6 months versus patients with cognitive complaints (0.243, 95% CI: 0.079 to 0.747, p = 0.014) and also in patients with first episode of MDD against with recurrent MDD (0.327 (95% CI: 0.136 to 0.787). Similarly, patients without cognitive complaints had healthier global functioning (lower mean SDS total score) than patients with cognitive complaints (8.3 vs 11.2; 95% CI, -5.189 to -0.578; p = 0.014). First depressive episode (lower risk of presenteeism), being male, and low baseline SDS total score (better global functioning) were also associated with improved outcomes. These results highlight the potential value of baseline PDQ-D scores in predicting subsequent workplace and global functioning in patients undergoing treatment for MDD.

Effects of 28 days of cannabis abstinence on cognition in major depressive disorder: A pilot study

BACKGROUND AND OBJECTIVES

Cannabis is a widely used substance that may impair select cognitive domains, including attention and memory. Problematic cannabis use is a common clinical problem among patients with major depressive disorder (MDD). Few studies have investigated the effects of cannabis abstinence on cognition in MDD. Thus, our study aimed to determine whether a 28-day period of cannabis abstinence is associated with improvements in cognition in patients with MDD and comorbid cannabis use disorder (CUD).

METHODS

We evaluated the effects of 28 days of cannabis abstinence on cognition in MDD patients with comorbid CUD facilitated by contingency management, motivational interviewing, psychoeducation, and coping-skills training (N = 11). Primary outcomes included Baseline to Day 28 changes in verbal memory and learning, while secondary outcomes included Baseline to Day 28 changes in working memory, visuospatial working memory (VSWM), visual search speed, mental flexibility, response inhibition, attention, manual dexterity, and fine motor movement.

RESULTS

Eight participants (72.7%) met the pre-specified criteria for cannabis abstinence and three participants significantly reduced their cannabis use (≥90%). Visual search speed, selective attention, and VSWM improved over the study period. These improvements were not associated with changes in cannabis metabolite levels from baseline to endpoint.

DISCUSSION AND CONCLUSIONS

Our findings suggest that 28 days of cannabis abstinence may improve select cognitive domains in patients with MDD and comorbid CUD.

SCIENTIFIC SIGNIFICANCE

This is the first study to longitudinally examine the effects of cannabis on cognition in MDD.

CLINICAL TRIAL

Effects of Cannabis Abstinence on Symptoms and Cognition in Depression (NCT03624933; https://www.

CLINICALTRIALS

gov).

Correlation between cognitive deficits and dorsolateral prefrontal cortex functional connectivity in first-episode depression

INTRODUCTION

Although depression is commonly accompanied by cognitive deficits, the underlying mechanism remains unclear. One possibility is that such deficits are related to abnormal brain network connections. The purpose of this study was thus to investigate changes in brain functional connectivity (FC) in depression and its relationship with cognitive deficits.

METHODS

We enrolled 37 first-episode MDD patients and 53 matched healthy controls (HC). All participants completed clinical and neurocognitive assessments and underwent resting-state functional MRI. Seed-based analysis was used to define the dorsolateral prefrontal cortex (DLPFC) and FC analysis was then performed. We used bias correlation to analyze the correlation between FC and clinical and neurocognitive scores.

RESULTS

MDD patients showed increased FC of the right DLPFC with the left inferior temporal gyrus, left cuneus, right inferior frontal gyrus, right anterior cingulate cortex, left BA39, right angular gyrus, right precuneus, left middle frontal gyrus, and right precentral gyrus. MDD patients also showed stronger FC in the left thalamus and reduced FC between the left superior occipital gyrus and left DLPFC seed region. Interestingly, increased FC was related to disease severity (with the right precentral gyrus) and social cognitive dysfunction (with the right angular gyrus) in MDD patients.

LIMITATIONS

The sample size was relatively small and it is unclear how age may influence FC changes in patients with depression.

CONCLUSIONS

These findings support changes in FC of the DLPFC in early MDD patients related to cognitive function. FC is a potential biomarker for the diagnosis of MDD.

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.

Utilization of passive visual perception task indetecting patients with major depressive disorder for active health

Depression is a common emotional and mental disease. At present, doctors' diagnosis mainly depends on the existing evaluation scales and their accumulated experience, lack of objective electrophysiological quantitative evaluation indicators. This study explores the difference in event-related potential (ERP) between patients with depression and healthy controls under the stimulation of multi-dimensional tasks, extracts the characteristic data, and uses a t-test for statistical analysis to provide an objective evaluation index for the clinical diagnosis of depression. Ninety-nine patients in the major depression group (MDD) and thirty patients in the healthy control group (HC) were used to compare the responses to positive, negative, and neutral stimulation, the results showed that there were significant differences between the left and right occipital lobes and one frontal lobe, and the frontal lobe showed lateralization; There were significant differences between the depression group and the healthy control group under multi-dimensional stimulation (P < 0.01), and the depression patients were significantly lower than the healthy patients. The results showed that emotional information was processed differently in patients with depression in the early stages of visual face processing. Therefore, EEG indices could be used as an objective index for the early detection of depression. Moreover, according to the instructions before the test, the subject is only asked to recognize visual pictures instead report emotional feelings. Stigma about psychiatric disorders could thus be reduced in this way. The explorations above facilitate designing more accurate and implicit active mental health techniques.

Features of cognitive impairment and related risk factors in patients with major depressive disorder: A case-control study

BACKGROUND

Cognitive impairment (CI) is a common symptom contributing to functional loss in major depressive disorder (MDD). However, the features of CI and its related risk factors in young and middle-aged MDD patients remain unclear.

METHODS

In this case-control study, 18- to 55-year-old acute-onset MDD patients and healthy controls (HCs) were recruited from nine centers in China. MDD patients were diagnosed based on the DSM-IV, the Mini-International Neuropsychiatric Interview, and a 17-item Hamilton Rating Scale for Depression score ≥ 14. Cognitive function, including attention/vigilance, learning, memory, processing speed and executive function, was assessed with a neuropsychological battery and compared between MDD patients and HCs. MDD patients scoring 1.5 SDs below the mean HC score in at least 2 domains were defined as having CI. Logistic regression analysis was used to identify risk factors for CI in MDD patients.

RESULTS

Compared with HCs (n = 302), MDD patients (n = 631) showed significant impairment in all cognitive domains (P < 0.001); 168 MDD patients (26.6%) had CI. Male sex (OR: 1.712; 95% CI: 1.165-2.514; P < 0.01) was positively correlated with CI; age of first onset (OR: 0.974; 95% CI: 0.957-0.991; P < 0.05) and comorbid anxiety disorders (OR: 0.514; 95% CI: 0.332-0.797; P < 0.01) were negatively correlated with CI.

LIMITATIONS

Biomarkers and neuroimaging were not used to investigate the possible biological mechanism and neural basis of CI in MDD.

CONCLUSIONS

CI was prominent in adults with acute-onset MDD; male sex and younger age of first onset were independent risk factors, and comorbid anxiety disorders were a protective factor.

Health-Related Quality of Life Over 6 Months in Patients With Major Depressive Disorder Who Started Antidepressant Monotherapy

OBJECTIVES

Major depressive disorder (MDD) is increasing worldwide and is associated with impaired quality of life (QOL). This study aimed to assess the QOL and its association with cognitive symptoms in patients with MDD who started antidepressant monotherapy.

METHODS

Data from the PERFORM (Prospective Epidemiological Research on Functioning Outcomes Related to Major Depressive Disorder) study were analyzed. A descriptive epidemiological analysis on EQ-5D-5L utility score, the level of each dimension, and the EuroQoL visual analog scale value was conducted at 4 visits during 6 months' follow-up. The association between cognitive complaints and changes in QOL measures was analyzed using multivariate linear regression analysis.

RESULTS

The median EQ-5D-5L utility score improved from 0.67 at baseline to 0.82 at month 6. Although the proportion of patients reporting level 1 (no problem) in every dimension of mobility, self-care, usual activities, pain/discomfort, and anxiety/depression increased over time, less than half of the patients achieved level 1 in pain/discomfort and depression/anxiety, which were closely related to depression and usual activities at month 6. Patients with no cognitive complaints or no history of MDD at baseline showed greater improvement in EQ-5D-5L utility scores and EuroQoL visual analog scale value for measuring QOL than those with these characteristics.

CONCLUSIONS

Treatment over 6 months improved QOL in patients with MDD although there remained room for improvement in dimensions of usual activities, pain/discomfort, and depression/anxiety. Cognitive complaints or history of MDD at baseline predicted less improvement in QOL at 6 months. Any history of MDD might delay improvement in QOL after treatment.

Delayed sleep-wake rhythm is associated with cognitive dysfunction, social dysfunction, and deteriorated quality of life in patients with major depressive disorder

BACKGROUND

The delayed sleep-wake phase is commonly observed in major depressive disorder (MDD) and thought to be associated with functional impairments. This study aimed to evaluate the relationship between the delayed sleep-wake phase, cognitive dysfunction, social dysfunction, and quality of life in patients with MDD.

METHODS

This cross-sectional design included 33 outpatients with MDD. Objective sleep-wake rhythm was assessed by actigraphy. Functional impairments were evaluated by the Japanese version of the Brief Assessment of Cognition in Schizophrenia (BACS-J), World Health Organization Disability Assessment Schedule (WHO-DAS), and Euro QOL 5 dimensions (EQ5D).

RESULTS

Actigraphic assessment of the delayed sleep-wake phase (midpoint of sleep) was significantly correlated with the composite score of the BACS-J (r = -0.489, p = 0.010), WHO-DAS score (r = 0.466, p = 0.014), and EQ5D score (r = 0.472, p = 0.013). No significant correlation was found between the other actigraphic sleep parameters (sleep latency, total sleep time, and sleep efficiency) and functional impairments.

CONCLUSION

Our study's results suggested that the delayed sleep-wake phase is associated with cognitive dysfunction, social dysfunction, and deteriorated quality of life in patients with MDD. Clinicians should pay attention to the sleep-wake rhythm in patients with MDD in clinical settings.

Inflammatory cytokines, cognition, and response to antidepressant treatment in patients with major depressive disorder

BACKGROUND

Inflammation and cognition are related to major depressive disorder (MDD), but the role in treatment response remains unclear. In this study, we investigated correlation between inflammatory cytokines and cognition in MDD patients treated with antidepressant medication.

METHODS

The participants were 149 MDD patients. Cytokines before therapy, cognitive assessments and severity of depression before and after therapy were tested. Logistic regression was used to explore underlying risks treatment response.

RESULTS

There were significant differences in smoking, alcohol drinking, and Stroop Color Test(SCT), Stroop Color-Word Test (SCWT), and Continuous Performance Test(CPT) scores between response group (RG) and non-response group (NRG) at baseline. Performance of patients in RG improved more in Brief Assessment of Cognition in Schizophrenia (BACS), Color Trial Test-I (CTT-I), SCT and SCWT after treatment. Levels of baseline IL-18 were associated with baseline learning and memory, and executive function. Treatment response was associated with drinking, performance of CPT and SCT.

CONCLUSION

MDD patients with different treatment responses have different cognitive defects, especially in speed of processing and executive function. Expression of cytokines is associated with cognition and may influence treatment response. Better speed of processing and executive function, and poorer attention at baseline may respond better to antidepressant treatment.

Safety, Tolerability, and Real-World Effectiveness of Intravenous Ketamine in Older Adults With Treatment-Resistant Depression: A Case Series

OBJECTIVE

To evaluate the safety, tolerability, and effectiveness of repeated doses of intravenous (IV) ketamine in older adults (i.e., ≥60 years of age) with treatment-resistant depression.

METHOD

In this case series, fifty-three older adults (M_age = 67, SD = 6; 57% female [n = 30]) received 4 IV ketamine infusions, administered over 1-2 weeks. Effectiveness of IV ketamine was measured using the Quick Inventory for Depressive Symptomatology-Self Report 16 (QIDS-SR16) approximately 2 days after infusions 1-3, and 1-2 weeks after infusion 4. Safety was measured as hemodynamic changes before, during, immediately after, and 20 minutes after each infusion. Tolerability was assessed via systematic reporting of treatment-emergent adverse events during and after each infusion, in addition to symptoms of dissociation measured using the Clinician Administered Dissociative States Scale. Partial response (25%-50% symptomatic improvement from baseline), response (≥50% symptomatic improvement from baseline), clinically significant improvements (≥25% symptomatic improvement from baseline), and remission rates (QIDS-SR16 ≤5) were also calculated.

RESULTS

Participants reported significant decreases in depressive symptoms (i.e., as measured by the QIDS-SR16) with repeated ketamine infusions (F(4, 92) = 7.412, p <0.001). The mean QIDS-SR16 score was 17.12 (SD = 5.33) at baseline and decreased to 12.52 (SD = 5.79) following 4 infusions. After 4 infusions, 31% (n = 8) of participants partially responded to IV ketamine, 27% (n = 7) responded, 58% (n = 15) experienced clinically significant improvements, and 10% (n = 3) met remission criteria. Thirty-six participants (69%) experienced treatment-emergent hypertension during at least 1 infusion, and 10 (19%) required intervention with an antihypertensive. Drowsiness was the most commonly reported adverse event (50% of infusions; n = 73).

CONCLUSION

Ketamine was associated with transient treatment-emergent hypertension. Response and remission rates were comparable to those reported in general adult samples. Findings are limited by the open-label, chart review nature of this study.

The effect of intravenous ketamine on cognitive functions in adults with treatment-resistant major depressive or bipolar disorders: Results from the Canadian rapid treatment center of excellence (CRTCE)

Ketamine may exert pro-cognitive effects on select measures of cognition in adults with mood disorders. We evaluated the effectiveness of intravenous (IV) ketamine on cognition in 68 adult outpatients with treatment-resistant depression (TRD) at the Canadian Rapid Treatment Center of Excellence between July 3, 2018 and April 16, 2020 (NCT04209296). Eligibility criteria for the present retrospective study included: primary diagnosis of major depressive or bipolar disorder; currently depressed; and insufficient response to two or more prior treatments. Participants received four infusions of ketamine hydrochloride (0.5-0.75 mg/kg) over 1-2 weeks. We assessed objective and subjective measures of cognition before and after two infusions, i.e., Digit Symbol Substitution Test (DSST), Trail Making Test-B (TMT-B), Patient Deficits Questionnaire, 5-item (PDQ-5-D). Ketamine significantly improved DSST (effect size [ES]=0.60), TMT-B (ES=0.84), as well as PDQ-5-D scores (ES=0.63), indicative of a moderate-to-large effect size. Improvements in DSST and PDQ-5-D with ketamine were mediated by reductions in depressive symptoms, whereas improvements in TMT-B were independent of changes in depressive symptoms. Our results support the independent, rapid-onset, pro-cognitive effects with IV ketamine in adults with TRD. Larger, randomized, controlled trials with ketamine wherein cognition is the primary outcome measure in mood and non-mood disorder samples are warranted.

Neurocognitive profiles of patients with first-episode and recurrent depression: a cross-sectional comparative study from China

BACKGROUND

Accumulating evidence has shown that cognitive deficits are prevalent among patients with major depressive disorder (MDD). However, the pattern and extent of cognitive deficits in patients with first-episode and recurrent depression remain unclear.

METHODS

Objective measures of cognitive function were assessed in 433 first-episode of depression (FED) patients, 206 recurrent major depression (RMD) patients during the acute phase and 287 healthy controls (HCs). Five domains of cognition (speed of processing, attention, verbal learning, visual learning and execution function) were assessed by seven neuropsychological tests. Neuropsychological data were transformed into T scores according to the Chinese norm.

RESULTS

Both FED and RMD patients displayed deficits of mild-to-medium severity across all cognitive domains and their subtests, relative to HCs (Cohen's d = 0.12-0.62). Among MDD patients, RMD patients exhibited poorer verbal learning (Cohen's d = 0.17) and visual learning (Cohen's d = 0.21) than FED patients.

CONCLUSIONS

MDD patients in the acute phase exhibited broad cognitive impairments, and there were significant differences in verbal and visual learning between FED and RMD patients. Our findings indicate that more attention should be paid to the domains of verbal and visual learning in future screening assessments and targeted interventions.

Loneliness-based impaired reward system pathway: Theoretical and clinical analysis and application

Loneliness is a key determinant in the etiology of mental health disorders such as depression and has profound impacts on health, quality of life, and economic productivity. This narrative review uses extant neurobiology and evolutionary literature to propose a construct through which loneliness may induce depression in adulthood via the reward system (including symptom and treatment aspects). Early childhood (distal) factors were found to be important in influencing adult (proximal) factors, which lead to the formulation of the construct. Due to the heterogenous and comorbid nature of depression, a new subtype known as 'reward depression' was distinguished along with distinct symptoms to aid practitioners when assessing patient treatment options. Furthermore, an evolutionary perspective was applied to the current impaired reward construct to discuss how the ancestral purpose and environment (in terms of reward) clashes with the modern one. Finally, theoretical treatment and prevention ideas were examined and discussed, leading into future work that needs to build upon and confirm the outlined construct.

Ecological momentary assessment of depressive symptoms using the mind.me application: Convergence with the Patient Health Questionnaire-9 (PHQ-9)

Ecological momentary assessment (EMA) for mental disorders, using application-based (app) technology capable of passive and ambient data collection, has been insufficiently evaluated and validated with rigorous, adequately-powered, high-quality studies. Herein, we sought to validate the mind.me application for the assessment of depressive symptoms in adults. Adults (ages 18-65) who self-identified as having clinically significant depressive symptoms [i.e. Patient Health Questionnaire 9 (PHQ-9) ≥ 5] utilized the mind.me app-a mobile phone technology that collects data passively and continuously, and is capable of integrating broad multimodal data [e.g., location variance (e.g. GPS), behavioural (e.g. social network activity), and communication data (e.g. SMS texting, phone calls)]. The primary outcome was predictive accuracy (i.e. convergent validity with depressive symptom measurement, as captured by the PHQ-9). 200 subjects were enrolled in the study (mean age 46 ± 12.71). The average PHQ-9 score was 12.8 ± 6.9. The predictive accuracy of the mind.me app was 0.91 ± 0.06. The sensitivity was 0.98 and the specificity was 0.93. The mind.me app was rated by 200 users as highly usable and informative to their illness. The mind.me app exhibits robust predictive accuracy in detecting depressive symptoms in adults with clinically relevant depressive symptoms. The mind.me app more specifically demonstrates convergence with the PHQ-9.

The Assessment of Cognitive Dysfunction in Major Depressive Disorder: A 16-Week Prospective Case-Control Study

OBJECTIVE

Cognitive dysfunction is one of the core components of major depressive disorder (MDD). It is estimated that two-thirds of patients diagnosed with MDD have cognitive deficits. Cognitive symptoms are pervasive and affect functioning in several domains. This 16-week prospective case-control study aimed to assess the change of mood and cognitive symptoms during treatment.

MATERIALS AND METHODS

Ninety-eight patients with MDD and 113 healthy controls (HCs) participated in the study. The MDD group was evaluated 6 times (baseline, 2nd, 4th, 8th, 12th, and 16th weeks). For mood symptoms, the Montgomery-Asberg Depression Rating Scale was used, and for neurocognitive functions, the Perceived Deficits Questionnaire-Depression was used, and the Digit Symbol Substitution Test was administered to both groups.

RESULTS

At baseline, compared with the HCs, the neurocognitive function of patients with MDD was worse. From the 8th to the 16th week assessments, in both neurocognitive tests, the cognitive functions of patients with MDD had improved. Despite this improvement and the patients achieving remission, the patients' cognitive performance did not improve to the level of the HC group at the 16th week.

CONCLUSION

Our longitudinal research revealed that even though mood symptoms decreased and patients with depression did achieve symptomatic remission, their cognitive deficits perpetuated.

Novel therapeutic targets in mood disorders: Pentoxifylline (PTX) as a candidate treatment

Numerous pharmacological treatments for mood disorders are currently available; however, rates of treatment resistance, relapse and recurrence remain high. Therefore, novel treatments acting outside of the conventionally targeted monoamine system are urgently needed to improve patient outcomes. Emerging and converging evidence suggests that immune dysfunction, oxidative stress, impaired cerebral blood flow (CBF) and decreased neurotrophic factors all contribute to mood disorder pathophysiology and are therefore treatment targets of interest. Pentoxifylline (PTX) is a phosphodiesterase inhibitor with potent anti-inflammatory and antioxidant effects, with additional pleiotropic effects that lead to improved CBF and increases in brain derived neurotrophic factor (BDNF) levels. The direct effect of non-specific phosphodiesterase inhibition may also improve alertness and cognitive function through enhancing second messenger systems. Replicated preclinical studies have demonstrated antidepressant-like effects in animal models. Small preliminary clinical trials have demonstrated promising results for antidepressant and procognitive effects, however, have yet to be replicated in larger mood disorder samples. Only one randomized clinical trial (RCT) specifically assessed the effects of adjunctive PTX in major depressive disorder (MDD), showing clinically and statistically significant antidepressant effects compared to placebo. No studies have assessed PTX in bipolar disorder (BD), where inflammation and altered CBF have also been strongly implicated. Taken together, PTX presents as a promising pleiotropic agent with several potential novel mechanisms of action meriting further evaluation in clinical trials to evaluate target engagement, antidepressant, procognitive and mood stabilizing effects.

From stress to depression: development of extracellular matrix-dependent cognitive impairment following social stress

Stress can predispose to depressive episodes, yet the molecular mechanisms regulating the transition from the initial stress response to a persistent pathological depressive state remain poorly understood. We profiled the development of an enduring depressive-like state by assessing affective behavior and hippocampal function during the 2 months following social-defeat stress. We measured remodeling of hippocampal extracellular matrix (ECM) during this period, as we recently identified ECM changes to mediate cognitive impairment during the sustained depressive-like state. Affective disturbance and cognitive impairments develop disparately after social stress, with gradual appearance of affective deficits. In contrast, spatial memory was impaired both early after stress and during the late-emerging chronic depressive-like state, while intact in-between. Similarly, we observed a biphasic regulation of the hippocampal ECM coinciding with hippocampus-dependent memory deficits. Together our data (1) reveal a dichotomy between affective and cognitive impairments similar to that observed in patients, (2) indicate different molecular processes taking place during early stress and the chronic depressive-like state, and (3) support a role of the ECM in mediating long-lasting effects on memory. From a translational point of view, it is important to prioritize on temporal phenotypic aspects in animal models to elucidate the underlying mechanisms of depression.

Ketamine as an antidepressant: overview of its mechanisms of action and potential predictive biomarkers

Ketamine, a drug introduced in the 1960s as an anesthetic agent and still used for that purpose, has garnered marked interest over the past two decades as an emerging treatment for major depressive disorder. With increasing evidence of its efficacy in treatment-resistant depression and its potential anti-suicidal action, a great deal of investigation has been conducted on elucidating ketamine's effects on the brain. Of particular interest and therapeutic potential is the ability of ketamine to exert rapid antidepressant properties as early as several hours after administration. This is in stark contrast to the delayed effects observed with traditional antidepressants, often requiring several weeks of therapy for a clinical response. Furthermore, ketamine appears to have a unique mechanism of action involving glutamate modulation via actions at the N-methyl-D-aspartate (NMDA) and α -amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, as well as downstream activation of brain-derived neurotrophic factor (BDNF) and mechanistic target of rapamycin (mTOR) signaling pathways to potentiate synaptic plasticity. This paper provides a brief overview of ketamine with regard to pharmacology/pharmacokinetics, toxicology, the current state of clinical trials on depression, postulated antidepressant mechanisms and potential biomarkers (biochemical, inflammatory, metabolic, neuroimaging sleep-related and cognitive) for predicting response to and/or monitoring of therapeutic outcome with ketamine.

The association of cognitive deficits with mental and physical Quality of Life in Major Depressive Disorder

BACKGROUND

Patients with Major Depressive Disorder experience significantly reduced subjective Quality of Life (QOL), including impaired social and emotional functioning and greater fatigue and physical pain. Mounting evidence suggests that cognitive dysfunction (e.g., deficits in memory, executive function) contributes independently to the onset of reduced QOL, however the domain-specific nature of this relationship has not been investigated. The present study examined the relationship between specific cognitive domains (e.g., attention, spatial cognition) and specific deficits in mental and physical QOL in subjects with lifetime MDD, as well as acutely depressed, remitted and healthy participants.

METHODS

Data were obtained (N = 387) from the Cognitive Function and Mood Study (COFAMS), a cross-sectional study of emotional, functional and cognitive status in individuals with mood disorders. Participants' (acutely depressed n = 93, remitted n = 170, and healthy control n = 124) QOL was assessed with the 36-Item Short Form Health Survey (SF-36) and cognitive functioning was evaluated with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), the Colorado Assessment Tests (CATs) and the Psychology Experiment Building Language (PEBL).

RESULTS

Analyses revealed that poor immediate and delayed memory were associated with reduced mental QOL in individuals with lifetime MDD, acutely depressed, and healthy controls. In contrast, cognitive functioning was not associated with mental QOL in remitted patients. No cognitive domains were significantly related to physical QOL in any participant group.

CONCLUSIONS

The result suggests that deficits in immediate and delayed memory may contribute to reduced mental QOL in acute MDD, whereas cognition does not appear to play a role in physical QOL. Memory should be considered important cognitive treatment targets for MDD patients suffering specifically from reduced mental QOL.

Reliability and Validity of THINC-it in Evaluating Cognitive Function of Patients with Bipolar Depression

PURPOSE

The THINC-integrated tool (THINC-it) as a brief screening tool can assesses cognitive impairment in patients with major depressive depression (MDD). Here, we aim to evaluate the reliability and validity of the THINC-it in a bipolar depression (BD-D) group in comparison with a healthy control (HC) group.

MATERIALS AND METHODS

Both groups were matched according to age, gender, years of education, and IQ. All participants completed the THINC-it test, including Spotter, Symbol Check, Codebreaker, Trails, and the Perceived Deficits Questionnaire for Depression-5-item (PDQ-5-D). The concurrent validity and internal consistency of the THINC-it test were analyzed, and 30 healthy controls were randomly sampled to retest THINC-it to verify the reliability of the THINC-it retest. The correlation between THINC-it and Hamilton Depression Scale (HAMD-17) and Sheehan Disability Scale (SDS) was also analyzed.

RESULTS

Fifty-eight patients with BD-D and 61 HCs were included for final analysis. There were significant mean difference (MD) standard errors (SE) between two groups in PDQ-5-D, Spotter and Codebreaker (all P<0.01), Trails (P=0.015). There was no significant difference in Symbol Check (MD (SE)=-0.01 (0.18), P=0.938; 95% CI=-0.38 to 0.35). The Cronbach's α of PDQ-5-D was 0.640. The intraclass correlation coefficient (ICC) was between 0.440 and 0.757. The highest concurrent validity was PDQ-5-D (r=0.812, P<0.001). PDQ-5-D was positively correlated with HAMD-17 and SDS score (P<0.01). The objective test had no significant correlation with HAMD-17 and SDS scores (P>0.05).

CONCLUSION

This study found that THINC-it can accurately present the cognitive impairment of patients with BD-D. It can be potentially applied in assessing the cognitive function of patients with BD-D although Symbol Check may not accurately reflect the level of cognitive function. The concurrent validity and retest reliability are lower than expected, we need to further increase the sample size to study.

Mood Disorders

PURPOSE OF REVIEW

This article discusses the prevalence of the major mood disorders (major depressive disorder and bipolar disorder) in the community and within neurologic settings, articulates the steps taken to make a diagnosis of major depressive disorder or bipolar disorder, and reviews old and newer treatment options with proven efficacy for the treatment of these two conditions.

RECENT FINDINGS

New medications are available as treatment options for major depressive disorder and bipolar disorder, such as intranasal and IV ketamine, and somatic treatments, such as deep brain stimulation and vagal nerve stimulators, are being used to target treatment-resistant depression.

SUMMARY

Mood disorders are common in neurologic settings. They are disabling and increase morbidity and mortality. Clinicians should have a high index of suspicion if they suspect their patients seem more distressed or incapacitated than would be warranted by their neurologic disorders. If a patient does have a mood disorder, validating the patient's experience, initiating treatment, and, if necessary, referring the patient to a primary care physician or psychiatrist are appropriate steps.

Risk factors for further sick leave among Japanese workers returning to work after an episode of major depressive disorder: a prospective follow-up study over 1 year

OBJECTIVES

We aimed to investigate the risk factors for further sick leave episodes among Japanese workers returning to work after time off with a major depressive disorder.

DESIGN

A prospective study with 1 year of follow-up.

PARTICIPANTS

We recruited 103 workers who had returned to work after taking sick leave with a major depressive disorder. Adjusted HRs with 95% CIs were calculated using Cox proportional hazard models to examine the risk of further sick leave.

RESULTS

In the adjusted analysis, we show that Social Adaptation Self-evaluation Scale scores (HR 0.95; p=0.019), 3-back correct response rate (N-back test) (HR 0.97; p<0.001) and benzodiazepine dosage (diazepam equivalent) (HR1.07; p=0.014) were associated with further episodes of sick leave.

CONCLUSIONS

Poorer social and cognitive functioning, together with higher diazepam dosages, were associated with an increased likelihood of additional sick leave.

Low-Frequency Pulsed Magnetic Field Improves Depression-Like Behaviors and Cognitive Impairments in Depressive Rats Mainly via Modulating Synaptic Function

Transcranial magnetic stimulation (TMS) has shown great promise as a medical treatment of depression. The effectiveness of TMS treatment at high frequency has been well investigated; however, low-frequency TMS in depression treatment has rarely been investigated in depression-induced cognitive deficits. Herein, this study was carried out to assess the possible modulatory role of low-frequency pulsed magnetic field (LFPMF) on reversing cognitive impairment in a model of depression induced by chronic unpredictable stress (CUS). Wistar rats were randomly allocated into four groups as follows: a control group (CON), a control applied with LFPMF (CON + LFPMF), a CUS group, and a CUS treated with LFPMF (CUS + LFPMF) group. During 8 weeks of CUS, compared to those in the CON group, animals not only gained less weight but also exhibited anhedonia, anxiety, and cognitive decline in behavioral tests. After 2-week treatment of LFPMF, a 20 mT, 1 Hz magnetic stimulation, it reversed the impairment of spatial cognition as well as hippocampal synaptic function including long-term potentiation and related protein expression. Thus, LFPMF has shown effectively improvements on depressant behavior and cognitive dysfunction in CUS rats, possibly via regulating synaptic function.

The glycine site of NMDA receptors: A target for cognitive enhancement in psychiatric disorders

Cognitive dysfunction is a principal determinant of functional impairment in major depressive disorder (MDD) and often persists during periods of euthymia. Abnormalities in the glutamate system, particularly in N-methyl-d-aspartate receptors (NMDARs) activity, have been shown to contribute to both mood and cognitive symptoms in MDD. The current narrative review aims to evaluate the potential pro-cognitive effects of targeting the glycine site of NMDARs in the treatment of psychiatric disorders, with a special focus on how these results may apply to MDD. Literature databases were searched from inception to May 2018 for relevant pre-clinical and clinical studies evaluating antidepressant and pro-cognitive effects of NMDAR glycine site modulators in both MDD and non-MDD samples. Six glycine site modulators with pro-cognitive and antidepressant properties were identified: d-serine (co-agonist), d-cycloserine (partial agonist), d-alanine (co-agonist), glycine (agonist), sarcosine (co-agonist) and rapastinel (partial agonist). Preclinical animal studies demonstrated improved neuroplasticity and pro-cognitive effects with these agents. Numerous proof-of-concept clinical trials demonstrated pro-cognitive and antidepressant effects trans-diagnostically (e.g., in healthy participants, MDD, schizophrenia, anxiety disorders, major neurocognitive disorders). The generalizability of these clinical studies was limited by the small sample sizes and the paucity of studies directly evaluating cognitive effects in MDD samples, as most clinical trials were in non-MDD samples. Taken together, preliminary results suggest that the glycine site of NMDARs is a promising target to ameliorate symptoms of depression and cognitive dysfunction. Additional rigorously designed clinical studies are required to determine the cognitive effects of these agents in MDD.

Characterizing, Assessing, and Treating Cognitive Dysfunction in Major Depressive Disorder

LEARNING OBJECTIVES

After participating in this activity, learners should be better able to:• Characterize cognitive dysfunction in patients with major depressive disorder.• Evaluate approaches to treating cognitive dysfunction in patients with major depressive disorder.

ABSTRACT

Cognitive dysfunction is a core psychopathological domain in major depressive disorder (MDD) and is no longer considered to be a pseudo-specific phenomenon. Cognitive dysfunction in MDD is a principal determinant of patient-reported outcomes, which, hitherto, have been insufficiently targeted with existing multimodal treatments for MDD. The neural structures and substructures subserving cognitive function in MDD overlap with, yet are discrete from, those subserving emotion processing and affect regulation. Several modifiable factors influence the presence and extent of cognitive dysfunction in MDD, including clinical features (e.g., episode frequency and illness duration), comorbidity (e.g., obesity and diabetes), and iatrogenic artefact. Screening and measurement tools that comport with the clinical ecosystem are available to detect and measure cognitive function in MDD. Notwithstanding the availability of select antidepressants capable of exerting procognitive effects, most have not been sufficiently studied or rigorously evaluated. Promising pharmacological avenues, as well as psychosocial, behavioral, chronotherapeutic, and complementary alternative approaches, are currently being investigated.

The screen for cognitive impairment in psychiatry (SCIP) is associated with disease severity and cognitive complaints in major depression

OBJECTIVE

To assess the relationship between the Screen for Cognitive Impairment in Psychiatry (SCIP) score and illness severity, subjective cognition and functioning in a cohort of major depressive disorder (MDD) patients.

METHODS

Patients (n = 40) diagnosed with MDD (DSM-IV-TR) completed the SCIP, a brief neuropsychological test, and a battery of self-administered questionnaires evaluating functioning (GAF, SDS, WHODAS 2.0, EDEC, PDQ-D5). Disease severity was evaluated with the Hamilton Depression Rating Scale (HDRS) and the Clinical Global Impression (CGI).

RESULTS

Age and sex were associated with performance in the SCIP. The SCIP-Global index score was associated with disease severity (r = -0.316, p < .05), the SDS, a patient self-assessment of daily functioning (r = -0.368, p < .05), and the EDEC subscales of patient-reported cognitive deficits (r = -0.388, p < .05) and their functional impacts (r = -0.335, p < .05). Multivariate analysis adjusted for age and sex confirmed these tests are independent predictors of performance in the SCIP (CGI-S, F_[3,34] = 4.478, p = .009; SDS, F_[3,34] = 3.365, p = .030; EDEC-perceived cognitive deficits, F_[3,34] = 5.216, p = .005; EDEC-perceived impacts of functional impairment, F_[3,34] = 5.154, p = .005).

CONCLUSIONS

This study confirms that the SCIP can be used during routine clinical evaluation of MDD, and that cognitive deficits objectively assessed in the SCIP are associated with disease severity and self-reported cognitive dysfunction and impairment in daily life.

Cognitive impairment in major depressive disorder

Cognitive dysfunction is a symptomatic domain identified across many mental disorders. Cognitive deficits in individuals with major depressive disorder (MDD) contribute significantly to occupational and functional disability. Notably, cognitive subdomains such as learning and memory, executive functioning, processing speed, and attention and concentration are significantly impaired during, and between, episodes in individuals with MDD. Most antidepressants have not been developed and/or evaluated for their ability to directly and independently ameliorate cognitive deficits. Multiple interacting neurobiological mechanisms (eg, neuroinflammation) are implicated as subserving cognitive deficits in MDD. A testable hypothesis, with preliminary support, posits that improving performance across cognitive domains in individuals with MDD may improve psychosocial function, workplace function, quality of life, and other patient-reported outcomes, independent of effects on core mood symptoms. Herein we aim to (1) provide a rationale for prioritizing cognitive deficits as a therapeutic target, (2) briefly discuss the neurobiological substrates subserving cognitive dysfunction, and (3) provide an update on current and future treatment avenues.

Activation therapy for the treatment of inpatients with depression - protocol for a randomised control trial compared to treatment as usual

BACKGROUND

Inpatients with depression have a poor long term outcome with high rates of suicide, high levels of morbidity and frequent re-admission. Current treatment often relies on pharmacological intervention and focuses on observation to maintain safety. There is significant neurocognitive deficit which is linked to poor functional outcomes. As a consequence, there is a need for novel psychotherapeutic interventions that seek to address these concerns.

METHODS

We combined cognitive activation and behavioural activation to create activation therapy (AT) for the treatment of inpatient depression and conducted a small open label study which demonstrated acceptability and feasibility. We propose a randomised controlled trial which will compare treatment as usual (TAU) with TAU plus activation therapy for adult inpatients with a major depressive episode. The behavioural activation component involves therapist guided re-engagement with previously or potentially rewarding activities. The cognitive activation aspect utilises computer based exercises which have been shown to improve cognitive function.

DISCUSSION

The proposed randomised controlled trial will examine whether or not the addition of this therapy to TAU will result in a reduced re-hospitalisation rate at 12 weeks post discharge. Subjective change in activation and objectively measured change in activity levels will be rated, and the extent of change to neurocognition will be assessed.

TRIAL REGISTRATION

Unique trial number: U1111-1190-9517. Australian New Zealand Clinical Trials Registry (ANZCTR) number: ACTRN12617000024347p .

Expert Consensus on Screening and Assessment of Cognition in Psychiatry

During the past two decades, it has been amply documented that neuropsychiatric disorders (NPDs) disproportionately account for burden of illness attributable to chronic non-communicable medical disorders globally. It is also likely that human capital costs attributable to NPDs will disproportionately increase as a consequence of population aging and beneficial risk factor modification of other common and chronic medical disorders (e.g., cardiovascular disease). Notwithstanding the availability of multiple modalities of antidepressant treatment, relatively few studies in psychiatry have primarily sought to determine whether improving cognitive function in MDD improves patient reported outcomes (PROs) and/or is cost effective. The mediational relevance of cognition in MDD potentially extrapolates to all NPDs, indicating that screening for, measuring, preventing, and treating cognitive deficits in psychiatry is not only a primary therapeutic target, but also should be conceptualized as a transdiagnostic domain to be considered regardless of patient age and/or differential diagnosis.

Conducting clinical studies targeting cognition in psychiatry: guiding principles and design

Cognitive dysfunction is common in many psychiatric disorders. While it has long been described as a core feature in schizophrenia, more recent data suggest qualitatively similar impairments in patients with bipolar disorder and major depressive disorder. There is compelling evidence to suggest that cognitive impairment contributes directly to functional disability and reduced quality of like across these disorders. As current treatments focus heavily on "primary" symptoms of mood and psychosis, the standard of care typically leaves cognitive deficits unmanaged. With this in mind, the field has recently begun to consider intervening directly on this important symptom domain, with several ongoing trials in schizophrenia. Fewer studies have targeted cognition in bipolar disorder and still fewer in MDD. With progress toward considering this domain as a target for treatment comes the need for consensus guidelines and methodological recommendations on cognitive trial design. In this manuscript, we first summarize the work conducted to date in this area for schizophrenia and for bipolar disorder. We then begin to address these same issues in MDD and emphasize the need for additional work in this area.

Social cognitive abilities predict psychosocial dysfunction in major depressive disorder

BACKGROUND

Major depressive disorder (MDD) is associated with social cognitive deficits (e.g., poor affect recognition and impaired theory of mind). However, the contribution of social cognitive issues to psychosocial dysfunction in MDD (e.g., occupational functioning and interpersonal relationships) has not been investigated. The current study evaluated the relationship between specific social cognitive domains (e.g., prosody interpretation) and psychosocial dysfunction in subjects with lifetime MDD, as well as currently depressed, remitted, and healthy controls (HCs) subjects.

METHOD

Data were obtained from 213 participants in the Cognitive Function and mood study (CoFaMS), a cross-sectional study of mood, social cognition, cold cognition, and psychosocial functioning in mood disorders. Participants' (current MDD n = 42, remitted MDD n = 69, and HCs n = 102) social cognitive abilities were assessed using the Social Perception subtest of the Wechsler Adult Intelligence Scale, and psychosocial dysfunction was clinically evaluated with the Functioning Assessment Short Test (FAST).

RESULTS

The results indicated that prosody interpretation, but not facial affect or meaning interpretation, was associated with psychosocial dysfunction in subjects with lifetime MDD, as well as remitted MDD subjects relative to HCs. In contrast, social cognition was not associated with functioning in participants with current MDD or in HCs.

CONCLUSIONS

These results suggest that the relationship between social cognition and psychosocial functioning differs between the acute and remitted stage of illness in MDD, and that prosody interpretation should be considered a treatment target in patients with residual psychosocial issues.

Cognitive impairment in depression: recent advances and novel treatments

In the past, little or no attention was paid to cognitive disorders associated with depression (a condition sometimes termed pseudodementia). However, recent years have seen a growing interest in these changes, not only because of their high frequency in acute-stage depression, but also because they have been found to persist, as residual symptoms (in addition to affective and psychomotor ones), in many patients who respond well to antidepressant treatment. These cognitive symptoms seem to impact significantly not only on patients' functioning and quality of life, but also on the risk of recurrence of depression. Therefore, over the past decade, pharmacological research in this field has focused on the development of new agents able to counteract not only depressive symptoms, but also cognitive and functional ones. In this context, novel antidepressants with multimodal activity have emerged. This review considers the different issues, in terms of disease evolution, raised by the presence of cognitive disorders associated with depression and considers, particularly from the neurologist's perspective, the ways in which the clinical approach to cognitive symptoms, and their interpretation to diagnostic and therapeutic ends, have changed in recent years. Finally, after outlining the pharmacodynamics and pharmacokinetics of the first multimodal antidepressant, vortioxetine, it reports the main results obtained with the drug in depressed patients, also in consideration of the ever-increasing evidence on its different mechanisms of action in animal models.

Applications of machine learning algorithms to predict therapeutic outcomes in depression: A meta-analysis and systematic review

BACKGROUND

No previous study has comprehensively reviewed the application of machine learning algorithms in mood disorders populations. Herein, we qualitatively and quantitatively evaluate previous studies of machine learning-devised models that predict therapeutic outcomes in mood disorders populations.

METHODS

We searched Ovid MEDLINE/PubMed from inception to February 8, 2018 for relevant studies that included adults with bipolar or unipolar depression; assessed therapeutic outcomes with a pharmacological, neuromodulatory, or manual-based psychotherapeutic intervention for depression; applied a machine learning algorithm; and reported predictors of therapeutic response. A random-effects meta-analysis of proportions and meta-regression analyses were conducted.

RESULTS

We identified 639 records: 75 full-text publications were assessed for eligibility; 26 studies (n=17,499) and 20 studies (n=6325) were included in qualitative and quantitative review, respectively. Classification algorithms were able to predict therapeutic outcomes with an overall accuracy of 0.82 (95% confidence interval [CI] of [0.77, 0.87]). Pooled estimates of classification accuracy were significantly greater (p < 0.01) in models informed by multiple data types (e.g., composite of phenomenological patient features and neuroimaging or peripheral gene expression data; pooled proportion [95% CI] = 0.93[0.86, 0.97]) when compared to models with lower-dimension data types (pooledproportion=0.68[0.62,0.74]to0.85[0.81,0.88]).

LIMITATIONS

Most studies were retrospective; differences in machine learning algorithms and their implementation (e.g., cross-validation, hyperparameter tuning); cannot infer importance of individual variables fed into learning algorithm.

CONCLUSIONS

Machine learning algorithms provide a powerful conceptual and analytic framework capable of integrating multiple data types and sources. An integrative approach may more effectively model neurobiological components as functional modules of pathophysiology embedded within the complex, social dynamics that influence the phenomenology of mental disorders.

The role of cognitive impairment in psychosocial functioning in remitted depression

BACKGROUND

Cognitive dysfunction is a prevalent and disabling symptom of Major Depressive Disorder (MDD), and is often retained in the remitted stage of illness. Emerging evidence suggests that cognitive impairment may be associated with dysfunction in a number of psychosocial domains (e.g., workplace productivity, social relationships). The current study explored the relationship between cognition and psychosocial functioning in remitted MDD and in healthy controls.

METHODS

Data were obtained from 182 participants of the Cognitive Function and Mood Study (CoFaM-S), a cross-sectional study of cognition, mood, and social cognition in mood disorders. Participants' (Remitted MDD n = 72, Healthy n = 110) cognition was assessed with a battery of cognitive tests including the Repeatable Battery for the Assessment of Neuropsychological Function (RBANS) and other standard measures of cognition (e.g., The Tower of London task). Psychosocial functioning was clinically evaluated with the Functioning Assessment Short Test (FAST).

RESULTS

The results indicated that executive functioning was the strongest independent predictor of functioning in remitted MDD patients, whereas various cognitive domains predicted psychosocial functioning in healthy individuals.

LIMITATIONS

Psychosocial functioning was measured with a clinical interview, and was therefore reliant on clinicians' judgement of impairment, as opposed to more objective measures of functioning.

CONCLUSIONS

These findings suggest that executive cognition plays an important role in functional recovery in remitted depression, and may be a crucial target in adjunctive treatment.

The Correlations among Depressive Symptoms, Cognitive Performance and Serum BDNF Levels in the Patients with Chronic Kidney Disease

OBJECTIVE

In the current study, we investigated whether there are relations among depressive symptoms, cognitive performance and serum BDNF levels in the patients with chronic kidney disease (CKD).

METHODS

Sixty patients with CKD and 65 healthy controls participated. Depressive symptoms were evaluated with Beck depression inventory (BDI) and Hamilton Depression Rating Scale (HDRS). Mini-Mental State Examination included in the Korean version of the Consortium to Establish a Registry for Alzheimer's disease (MMSE-KC) assessment packet was used for the evaluation of overall cognitive function. To assess memory function, the Korean version of the Hopkins Verbal Learning Test (K-HVLT) was used. BDNF levels were measured using an enzyme-linked immunosorbent assay (ELISA) kit.

RESULTS

The CKD patients showed more depressive symptoms when compared with controls. The depressive symptoms and cognitive function were not associated with serum BDNF levels in the CKD patients.

CONCLUSION

In the current study, CKD patients had more depressive symptoms when compared controls. However, the serum BDNF levels of CKD patients were not associated with depressive symptoms and cognitive functions. These findings suggested that the serum BDNF levels may not be reflect the cognitive function and depressive mood state in the CKD patients.