The lack of meaningful association between depression severity measures and neurocognitive performance

Alterations in performance and discriminating power of the death/suicide implicit association test across the lifespan

The Death/Suicide Implicit Association Test (d/s-IAT) has differentiated individuals with prior and prospective suicide attempts in previous studies, however, age effects on test results remains to be explored. A three-site study compared performance on the d/s-IAT among participants aged 16-80 years with depression and prior suicide attempt (n = 82), with depression and no attempts (n = 80), and healthy controls (n = 86). Outcome measures included the standard difference (D) score, median reaction times, and error rates. Higher D scores represent a stronger association between death/suicide and self, while lower scores represent a stronger association between life and self. The D scores differed significantly among groups overall. Participants with depression exhibited higher scores compared to healthy controls, but there was no difference between participants with and without prior suicide attempts(F[2,242]=8.76, p<.001). Response times for participants with prior attempts differed significantly from other groups, with no significant differences in error rates. The D score was significantly affected by age (β =-0.007, t = 3.65, p<.001), with slowing of response times in older ages. Results suggest reaction time d/s-IAT D scores may not distinguish implicit thinking about suicide as response times slow with age, but slowed response times may be sensitive to suicide risk potentially indicating basic information processing deficits.

Cluster analysis dissecting cognitive deficits in older adults with major depressive disorder and the association with neurofilament light chain

BACKGROUND

Cognitive impairment is a growing problem with increasing burden in global aging. Older adults with major depressive disorder (MDD) have higher risk of dementia. Neurofilament light chain (NfL) has been proven as a potential biomarker in neurodegenerative disease, including dementia. We aimed to investigate the association between cognitive deficits and NfL levels in older adults with MDD.

METHODS

In this cross-sectional study, we enrolled 39 MDD patients and 15 individuals with mild neurocognitive disorder or major neurocognitive disorder, Alzheimer's type, as controls, from a tertiary psychiatric hospital. Both groups were over age 65 and with matched Mini-Mental State Examination (MMSE) score. Demographic data, clinical variables, and plasma NfL levels were obtained. We used cluster analysis according to their cognitive profile and estimated the correlation between plasma NfL levels and each cognitive domain.

RESULTS

In the MDD group, participants had higher rate of family psychiatry history and current alcohol use habit compared with controls. Control group of neurocognitive disorders showed significantly lower score in total MMSE and higher plasma NfL levels. Part of the MDD patients presented cognitive deficits clustered with that of neurocognitive disorders (cluster A). In cluster A, the total MMSE score (r=-0.58277, p=0.0287) and the comprehension domain (r=-0.71717, p=0.0039) were negatively correlated to NfL levels after adjusting for age, while the associations had not been observed in the other cluster.

CONCLUSIONS

We noted the negative correlation between NfL levels and cognition in MDD patients clustered with neurodegenerative disorder, Alzheimer's type. NfL could be a promising candidate as a biomarker to predict subtype of patients in MDD to develop cognitive decline. Further longitudinal studies and within MDD cluster analysis are required to validate our findings for clinical implications.

Transdiagnostic subgroups of cognitive impairment in early affective and psychotic illness

Cognitively impaired and spared patient subgroups were identified in psychosis and depression, and in clinical high-risk for psychosis (CHR). Studies suggest differences in underlying brain structural and functional characteristics. It is unclear whether cognitive subgroups are transdiagnostic phenomena in early stages of psychotic and affective disorder which can be validated on the neural level. Patients with recent-onset psychosis (ROP; N = 140; female = 54), recent-onset depression (ROD; N = 130; female = 73), CHR (N = 128; female = 61) and healthy controls (HC; N = 270; female = 165) were recruited through the multi-site study PRONIA. The transdiagnostic sample and individual study groups were clustered into subgroups based on their performance in eight cognitive domains and characterized by gray matter volume (sMRI) and resting-state functional connectivity (rsFC) using support vector machine (SVM) classification. We identified an impaired subgroup (NROP = 79, NROD = 30, NCHR = 37) showing cognitive impairment in executive functioning, working memory, processing speed and verbal learning (all p < 0.001). A spared subgroup (NROP = 61, NROD = 100, NCHR = 91) performed comparable to HC. Single-disease subgroups indicated that cognitive impairment is stronger pronounced in impaired ROP compared to impaired ROD and CHR. Subgroups in ROP and ROD showed specific symptom- and functioning-patterns. rsFC showed superior accuracy compared to sMRI in differentiating transdiagnostic subgroups from HC (BACimpaired = 58.5%; BACspared = 61.7%, both: p < 0.01). Cognitive findings were validated in the PRONIA replication sample (N = 409). Individual cognitive subgroups in ROP, ROD and CHR are more informative than transdiagnostic subgroups as they map onto individual cognitive impairment and specific functioning- and symptom-patterns which show limited overlap in sMRI and rsFC. CLINICAL TRIAL REGISTRY NAME: German Clinical Trials Register (DRKS). Clinical trial registry URL: https://www.drks.de/drks_web/ . Clinical trial registry number: DRKS00005042.

Plasma Phospholipid Polyunsaturated Fatty Acid Associations with Neurocognition

Neurocognitive deficits are implicated in major depressive disorder (MDD) and suicidal behavior, and cognitive function may be affected by blood levels of polyunsaturated fatty acids (PUFAs). Neuroprotective functions have been described for omega-3 (n-3) PUFAs, while omega-6 (n-6) PUFAs exhibit broadly opposing activities. Both classes of PUFAs are linked to MDD and suicidal behavior. However, few studies have investigated the relationships between PUFAs and neurocognitive function with respect to MDD or suicidal behavior. Among participants with MDD (n = 45) and healthy volunteers (HV, n = 30) we assessed performance on tasks of attentional capacity and executive function and its relationship to plasma phospholipid PUFA levels, expressed as a percentage of total plasma phospholipids, for eicosapentaenoic acid (EPA%), docosahexaenoic acid (DHA%), and arachidonic acid (AA%). Regression models tested the correlations between PUFA levels and task performance in three groups: MDD with a history of suicide attempt (SA, n = 20), MDD with no attempts (NA, n = 25), and HV. Interaction testing indicated a significant positive correlation of EPA% with continuous performance test scores in the NA group (F = 4.883, df = 2,72, p = 0.01), a measure of sustained attention. The AA% correlated negatively with performance on two executive function tasks, object alternation (beta = -3.97, z-score = -2.67, p = 0.008) and the Wisconsin card sort (beta = 0.80, t-score = -2.16, df = 69, p = 0.035), after adjustment for group and age, with no group effects. Our findings suggest a role for PUFA imbalance in attentional functioning and executive performance; however, no MDD-specific effect was observed.

Deficits in specific executive functions manifest by severity in major depressive disorder: a comparison of antidepressant naïve inpatient, outpatient, subclinical, and healthy control groups

Introduction

Previous research has highlighted the executive function (EF) deficits present in depressed patients; however, conflicting results exist regarding the impact of depression severity on the size of these deficits. This study aimed to compare deficits in EF between antidepressant naïve inpatient and outpatient depressed, a group with subclinical depression symptoms, and a healthy control group while controlling for education, sex, and age.

Methods

In cross-sectional research, 245 antidepressant naive participants (46 inpatient, 68 outpatient, 65 subclinical, and 67 healthy control individuals) were recruited by convenience sampling. The Structured Clinical Interview for DSM-5 Disorders (SCID-5) and Beck Depression Inventory-II (BDI-II) were used to assess depression. EF was measured using several neuropsychological tests, including the Stroop Color-Word Test, the Wisconsin Card Sorting Test, and the N-back Test, which assessed the components of Inhibition, Shifting, and Updating, respectively. Multivariate analysis of covariance revealed a significant difference between the groups in EF components (p < 0.001). Pairwise comparisons further showed that inpatient and outpatient patients had more depressive symptoms and worse EF performance than subclinical and healthy control groups (p < 0.05).

Results

In the analysis of EF measures, a significant difference was found among the four groups, with post-hoc tests revealing variations in specific EF components. Overall, patients with more severe depressive symptoms show more deficits in EF. Additionally, correlations between clinical characteristics and EF measures varied across patient groups, but many correlations became non-significant after adjusting for the false discovery rate (FDR).

Discussion

This study emphasizes the impact of depression severity on deficits in the EF of depressed patients and at-risk populations. Consequently, it is important to consider executive dysfunctions as an underlying vulnerability in the development and persistence of depressive disorder.

The magnitude of neurocognitive impairment is overestimated in depression: the role of motivation, debilitating momentary influences, and the overreliance on mean differences

BACKGROUND

Meta-analyses agree that depression is characterized by neurocognitive dysfunctions relative to nonclinical controls. These deficits allegedly stem from impairments in functionally corresponding brain areas. Increasingly, studies suggest that some performance deficits are in part caused by negative task-taking attitudes such as poor motivation or the presence of distracting symptoms. A pilot study confirmed that these factors mediate neurocognitive deficits in depression. The validity of these results is however questionable given they were based solely on self-report measures. The present study addresses this caveat by having examiners assess influences during a neurocognitive examination, which were concurrently tested for their predictive value on performance.

METHODS

Thirty-three patients with depression and 36 healthy controls were assessed on a battery of neurocognitive tests. The examiner completed the Impact on Performance Scale, a questionnaire evaluating mediating influences that may impact performance.

RESULTS

On average, patients performed worse than controls at a large effect size. When the total score of the Impact on Performance Scale was accounted for by mediation analysis and analyses of covariance, group differences were reduced to a medium effect size. A total of 30% of patients showed impairments of at least one standard deviation below the mean.

CONCLUSIONS

This study confirms that neurocognitive impairment in depression is likely overestimated; future studies should consider fair test-taking conditions. We advise researchers to report percentages of patients showing performance deficits rather than relying solely on overall group differences. This prevents fostering the impression that the majority of patients exert deficits, when in fact deficits are only true for a subgroup.

Cognitive phenotypes in late-life depression

OBJECTIVE

To identify cognitive phenotypes in late-life depression (LLD) and describe relationships with sociodemographic and clinical characteristics.

DESIGN

Observational cohort study.

SETTING

Baseline data from participants recruited via clinical referrals and community advertisements who enrolled in two separate studies.

PARTICIPANTS

Non-demented adults with LLD (n = 120; mean age = 66.73 ± 5.35 years) and non-depressed elders (n = 56; mean age = 67.95 ± 6.34 years).

MEASUREMENTS

All completed a neuropsychological battery, and individual cognitive test scores were standardized across the entire sample without correcting for demographics. Five empirically derived cognitive domain composites were created, and cluster analytic approaches (hierarchical, k-means) were independently conducted to classify cognitive patterns in the depressed cohort only. Baseline sociodemographic and clinical characteristics were then compared across groups.

RESULTS

A three-cluster solution best reflected the data, including "High Normal" (n = 47), "Reduced Normal" (n = 35), and "Low Executive Function" (n = 37) groups. The "High Normal" group was younger, more educated, predominantly Caucasian, and had fewer vascular risk factors and higher Mini-Mental Status Examination compared to "Low Executive Function" group. No differences were observed on other sociodemographic or clinical characteristics. Exploration of the "High Normal" group found two subgroups that only differed in attention/working memory performance and length of the current depressive episode.

CONCLUSIONS

Three cognitive phenotypes in LLD were identified that slightly differed in sociodemographic and disease-specific variables, but not in the quality of specific symptoms reported. Future work on these cognitive phenotypes will examine relationships to treatment response, vulnerability to cognitive decline, and neuroimaging markers to help disentangle the heterogeneity seen in this patient population.

Sex differences in subjective cognitive impairment and clinical correlates in Chinese patients with subthreshold depression

OBJECTIVE

Subthreshold depression (SD) is a global mental health problem given its high prevalence, comorbidity, functional impairment, and its association with increased service utilization. However, currently little is known about sex differences of SD in cognitive impairment with clinical correlates. This study aims to explore sex differences in subjective cognitive impairment and clinically associated risk factors in Chinese patients with subthreshold depression (SD).

METHODS

A total of 126 patients with SD, 40 males and 86 females, aged 18-45 years, were included in this cross-sectional observational study. Their general information, psychological assessments, and psychiatric symptom assessments were collected online. The Patient Health Questionnaire depression-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), Perceived Deficits Questionnaire-Depression (PDQ-D), and Toronto Alexithymia Scale (TAS-20) with 3 subdomains were used. The obtained scores were analyzed with partial correlation and multiple linear regression analysis models.

RESULTS

Our results showed that females had significantly higher PDQ-D-20 total score than males. However, the differences in TAS-20 and subdomain score according to sex were not significant. Notably, TAS-20 and DDF (difficulty describing feelings) subdomain contributed to cognitive impairment in males, whereas both PHQ-9 total score and TAS-20 or DDF subdomain contributed to cognitive impairment in females.

CONCLUSION

These findings revealed significant sex differences in cognitive impairment and clinical correlates in SD, which should be further followed-up in the future.

Validation of the Hungarian version of the Cognitive Failures Questionnaire (CFQ)

Cognitive Failures Questionnaire (CFQ) is a widely utilized tool to measure the frequency of everyday cognitive lapses. Here we present a validation study of the Hungarian translation of CFQ. A subsample (n = 157) filled out the questionnaire twice within a 7-21 days interval to determine test-retest reliability. Exploratory structural equation modeling (ESEM) method was run on a larger sample (n = 382) for testing a different number of potential factors. Although the multiple-factor solutions showed good fit, the one-factor solution described the data more adequately. The composite reliability of the final model (CR = .822) as well as test-retest reliability (intraclass correlation coefficient = .900) and the internal consistency (Cronbach's alpha = .920) of the CFQ were high. Higher CFQ scores (i.e., more cognitive slips) correlated positively with anxiety and depression while a negative relationship was present with well-being. Furthermore, women were characterized with higher CFQ scores compared to men. Our results are in line with previous studies, and the excellent psychometric properties make the Hungarian version of CFQ an appropriate measure of cognitive failures.

Can brain stimulation enhance cognition in clinical populations? A critical review

Many psychiatric and neurological conditions are associated with cognitive impairment for which there are very limited treatment options. Brain stimulation methodologies show promise as novel therapeutics and have cognitive effects. Electroconvulsive therapy (ECT), known more for its related transient adverse cognitive effects, can produce significant cognitive improvement in the weeks following acute treatment. Transcranial magnetic stimulation (TMS) is increasingly used as a treatment for major depression and has acute cognitive effects. Emerging research from controlled studies suggests that repeated TMS treatments may additionally have cognitive benefit. ECT and TMS treatment cause neurotrophic changes, although whether these are associated with cognitive effects remains unclear. Transcranial electrical stimulation methods including transcranial direct current stimulation (tDCS) and transcranial alternating current stimulation (tACS) are in development as novel treatments for multiple psychiatric conditions. These treatments may also produce cognitive enhancement particularly when stimulation occurs concurrently with a cognitive task. This review summarizes the current clinical evidence for these brain stimulation treatments as therapeutics for enhancing cognition. Acute, or short-lasting, effects as well as longer-term effects from repeated treatments are reviewed, together with potential putative neural mechanisms. Areas of future research are highlighted to assist with optimization of these approaches for enhancing cognition.

Kundalini Yoga for Post-Treatment Lyme Disease: A Preliminary Randomized Study

This study examined the adherence to and the potential benefit of Kundalini yoga (KY) for post-treatment Lyme disease syndrome (PTLDS). Participants were randomly assigned to 8 weeks of a KY small-group intervention or a waitlist control (WLC). Adherence was measured as attendance at KY group sessions. Primary outcomes assessed pain, pain interference, fatigue, and global health. Secondary outcomes assessed multisystem symptom burden, mood, sleep, physical and social functioning, cognition, and mindfulness. Linear mixed models were used to test changes in outcomes over time as a function of group assignment; intercepts for participants were modeled as random effects. Although the target sample size was 40 participants, the study concluded with 29 participants due to recruitment challenges. No KY participants dropped out of the study, and participants attended 75% of group sessions on average, but WLC retention was poor (57%). Regarding primary outcomes, there was no significant interaction between group and time. Regarding secondary outcomes, there was a significant interaction between group and time for multisystem symptom burden (p < 0.05) and cognition (p < 0.01); KY participants reported improved multisystem symptom burden and cognition over the course of the study compared to WLC participants. To enhance recruitment and retention, future trials may consider expanding geographic access and including supportive procedures for WLC participants. This preliminary study supports the need for a larger study to determine if KY reduces multisystem symptom burden and enhances cognition among people with PTLDS.

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.

Ketamine vs midazolam: Mood improvement reduces suicidal ideation in depression

OBJECTIVE

Studies demonstrate rapid antidepressant and anti-suicidal ideation effects of subanesthetic ketamine. The specific subcomponents of depression that are most closely tied to reduction of suicidal ideation with ketamine treatment are less explored.

METHODS

Exploratory, post hoc analysis of data from a randomized clinical trial of ketamine vs midazolam in patients with major depressive disorder (MDD) and clinically significant suicidal ideation examined changes in factor analysis-derived symptom clusters from standard measures of depression (Hamilton Depression Rating Scale, HDRS; Beck Depression Inventory, BDI) and mood disturbance (Profile of Mood States, POMS), and their relationship to severity of suicidal ideation (Beck Scale for Suicidal Ideation; SSI). Ratings obtained before and one day after blinded intravenous infusion were decomposed into component factors or published subscales. Treatment effects on factors/subscales were compared between drugs, correlations with changes in suicidal ideation were tested, and stepwise regression was used to derive predictors of change in SSI.

RESULTS

Factor scores for HDRS Psychic Depression, HDRS Anxiety, BDI Subjective Depression, POMS Depression and POMS Fatigue improved more with ketamine than midazolam. Stepwise regression showed across both drugs that improvement in HDRS Psychic Depression, POMS Depression, and HDRS Anxiety predicted 51.6% of the variance in reduction of suicidal ideation.

LIMITATIONS

Secondary analysis of clinical trial data.

CONCLUSIONS

Ketamine's rapid effects on suicidal ideation appear to be mostly a function of its effects on core mood and anxiety symptoms of MDD, with comparatively little contribution from neurovegetative symptoms with the potential exception of vigor/fatigue.

TRIAL REGISTRATION

Data used in this secondary analysis came from ClinicalTrials.gov identifier: NCT01700829.

Subjective cognition in adults with common psychiatric classifications; a systematic review

The aim is to assess whether instruments developed to measure subjective cognitive complaints (SCCs) and in neurology and aging can reliably be used in ADHD and other common psychiatric classifications. MEDLINE, PsycINFO, CINAHL and EMBASE+EMBASE CLASSIC were searched for relevant work on SCCs in psychiatric classifications (ADHD, autism, mood disorders, schizophrenia) in two phases: 1 identify instruments, 2 relevant studies. 35 studies with varying study quality were included. SCCs are most commonly studied in ADHD and mood disorders, but are found in all psychiatric classifications. SCCs show inconsistent and low associations to objective cognition across disorders, but higher and consistent relations are found with behavioral outcomes. SCCs are not qualitatively different for ADHD compared to other psychiatric classifications, and should thus not be seen as analogous to well validated measures of objective cognition. However, SCCs do reflect suffering, behavioral difficulties and problems experienced by across those with psychiatric problems in daily life.

The Relationship Between Cognitive Functioning and Symptoms of Depression, Anxiety, and Post-Traumatic Stress Disorder in Adults with a Traumatic Brain Injury: a Meta-Analysis

A thorough understanding of the relationship between cognitive test performance and symptoms of depression, anxiety, or post-traumatic stress disorder (PTSD) in people with traumatic brain injury (TBI) is important given the high prevalence of these emotional symptoms following injury. It is also important to understand whether these relationships are affected by TBI severity, and the validity of test performance and symptom report. This meta-analysis was conducted to investigate whether these symptoms are associated with cognitive test performance alterations in adults with a TBI. This meta-analysis was prospectively registered on the PROSPERO International Prospective Register of Systematic Reviews website (registration number: CRD42018089194). The electronic databases Medline, PsycINFO, and CINAHL were searched for journal articles published up until May 2020. In total, 61 studies were included, which enabled calculation of pooled effect sizes for the cognitive domains of immediate memory (verbal and visual), recent memory (verbal and visual), attention, executive function, processing speed, and language. Depression had a small, negative relationship with most cognitive domains. These relationships remained, for the most part, when samples with mild TBI (mTBI)-only were analysed separately, but not for samples with more severe TBI (sTBI)-only. A similar pattern of results was found in the anxiety analysis. PTSD had a small, negative relationship with verbal memory, in samples with mTBI-only. No data were available for the PTSD analysis with sTBI samples. Moderator analyses indicated that the relationships between emotional symptoms and cognitive test performance may be impacted to some degree by exclusion of participants with atypical performance on performance validity tests (PVTs) or symptom validity tests (SVTs), however there were small study numbers and changes in effect size were not statistically significant. These findings are useful in synthesising what is currently known about the relationship between cognitive test performance and emotional symptoms in adults with TBI, demonstrating significant, albeit small, relationships between emotional symptoms and cognitive test performance in multiple domains, in non-military samples. Some of these relationships appeared to be mildly impacted by controlling for performance validity or symptom validity, however this was based on the relatively few studies using validity tests. More research including PVTs and SVTs whilst examining the relationship between emotional symptoms and cognitive outcomes is needed.

Characteristics associated with the discrepancy between subjective and objective executive functioning in depression

Major depressive disorder (MDD) is associated with both self-reported (subjective) cognitive complaints and deficits in neurocognitive (objective) measures, but the correspondence between subjective and objective measures of cognition is low. This cross-sectional study aimed to (1) assess the association between subjective and objective measures of executive functions (EFs), and (2) explore factors associated with the discrepancy between subjective and objective EFs in MDD. Sixty-two participants with current or previous mild to moderate MDD and subjective EF complaints completed a clinical trial baseline assessment. An objective EF composite score was drawn from six neurocognitive measures, while the Behavior Rating Inventory of Executive Function-Adult version was applied as a measure of subjective EF. The association between the subjective and objective composites was evaluated using Spearman's rank order correlation. A discrepancy score was calculated to quantify the difference between subjective and objective EF. Factors associated with the discrepancy score were analyzed using regression analysis (p < .05). Participants reported extensive EF difficulties, but most performed in the normal range on objective EF measures. A weak correlation was detected between the subjective and objective measures (r_s = .015). More rumination (β = -.364) and higher IQ (β = -.420) were associated with reporting more subjective complaints than was evident from objective measures of EF (i.e., underestimation). Subjective and objective EF measures are weakly overlapping in MDD. Findings underscore recommendations to include both subjective and objective measures when assessing EFs in depression. In addition, findings suggest that targeting ruminative processes could help correct underestimation.

Clinical Neuropsychological Evaluation in Older Adults With Major Depressive Disorder

PURPOSE OF THE REVIEW

Older adults with major depressive disorder are particularly vulnerable to MDD-associated adverse cognitive effects including slowed processing speed, decreased attention, and executive dysfunction. The purpose of this review is to describe the approach to a clinical neuropsychological evaluation in older adults with MDD. Specifically, this review compares and contrasts neurocognitive screening and clinical neuropsychological evaluation procedures and details the multiple components of the clinical neuropsychological evaluation.

RECENT FINDINGS

Research has shown that neurocognitive screening serves a useful purpose to provide an acute and rapid assessment of global cognitive function; however, it has limited sensitivity and specificity. The clinical neuropsychological evaluation process is multifaceted and encompasses a review of available medical records, neurobehavioral status and diagnostic interview, comprehensive cognitive and clinical assessment, examination of inclusion and diversity factors as well as symptom and performance validity, and therapeutic feedback. As such, the evaluation provides invaluable information on multiple cognitive functions, establishes brain and behavior relationships, clarifies neuropsychiatric diagnoses, and can inform the etiology of cognitive impairment. Clinical neuropsychological evaluation plays a unique and critical role in integrated healthcare for older adults with MDD. Indeed, the evaluation can serve as a nexus to synthesize information across healthcare providers in order to maximize measurement-based care that can optimize personalized medicine and overall health outcomes.

Machine learning to predict clinical remission in depressed patients after acute phase selective serotonin reuptake inhibitor treatment

OBJECTIVE

Selective serotonin reuptake inhibitors (SSRIs) are suggested as the first-line treatment for patients with major depressive disorder (MDD), but the remission rate is unsatisfactory. We aimed to establish machine learning models and explore variables available at baseline to predict the 8-week outcome among patients taking SSRIs.

METHODS

Data from 400 patients were used to build machine learnings. The last observation carried forward approach was used to determine the remitter/non-remitter status of the patients at week 8. Using least absolute shrinkage and selection operator (LASSO) to select features, we built 4 different machine learning algorithms including gradient boosting decision tree, support vector machine (SVM), random forests, and logistic regression with five-fold cross-validation. Then, we adopted Shapley additive explanations (SHAP) values to interpret the model output.

RESULTS

The remission rate is 67.8%. We obtained 78 features from the baseline characteristics, including 25 sociodemographic characteristics, 31 clinical features, 15 psychological traits and 7 neurocognitive functions, and 13 of these features were selected to establish SVM. The accuracy of the SVM prediction is 74.49%, reaching an average area under the curve of 0.734±0.043. The sensitivity is 0.899±0.038 with a positive predictive value of 0.776±0.028. The specificity is 0.422±0.091 with a negative predictive value of 0.674±0.086. According to the SHAP values, neurocognitive functions and anxiety and hypochondriasis symptoms were important predictors.

CONCLUSION

Our study supports the utilization of machine learning approaches with inexpensive and highly accessible variables to accurately predict the 8-week treatment outcome of SSRIs in patients with MDD.

Performances on individual neurocognitive tests by people experiencing a current major depression episode: A systematic review and meta-analysis

BACKGROUND AND PURPOSES

Previous meta-analyses on neurocognitive test performances in depression have provided effect sizes for cognitive domains. Most domain effect sizes have medium to high variance heterogeneity. Restriction to each test performance could reduce variance and clarify differing test effect sizes. This systematic review and meta-analysis were done to 1. provide effect sizes for cognitive performances (test, subtest, or multiple measures within tests), and 2. investigate age as an effect modifier.

METHODS

Inclusion criteria were: 1. active major depression episode (MD), 2. a control group, 3 reported means and standard deviations, 4. non-computerized tests previously studied at least 3 times. Meta-analyses were performed using Cochrane Review Manager. Age under versus over 45 was investigated as an effect moderator.

RESULTS

Twenty-seven studies met criteria. MD patients performed significantly poorer on 16 of 16 neurocognitive measures (random effects d = -0.47 to -0.92 across tests). Variance was heterogeneous for 11 of 16 measures. Differences between cognitive measures were largely absent based on overlapping 95% confidence intervals. Effect sizes did not differ under versus over 45 years.

LIMITATIONS

Bias risk assessment showed limited control for subject selection, comparability of depressed and control groups, pre-morbid intelligence, drug treatment, and effort in testing.

CONCLUSIONS

The depression - cognition effect was in the moderate to large range regardless of test type. Variance heterogeneity was substantial despite exclusion of inactive depression and the absence of test pooling. The size of the depression - cognition effect was not a function of age.

Weak associations between depressive symptom severity, depressive symptom clusters, and cognitive performance in young to middle-aged men without clinical depression

Evidence suggests different depressive symptoms are related to  specific aspects of cognition, especially in older adults. The current study extended this literature by examining depressive symptom severity, symptom clusters, and cognitive functioning in young-to-middle aged adults. A sample of 2,560 men (mean age = 38.12 ± 2.41 years) withvalid Minnesota Multiphasic Personality Inventories (MMPI) and completed cognitive measures was drawn from a Vietnam veterans study. Bootstrapped regressions examined relationships between cognitive performance, MMPI Depression  scores, and Harris-Lingoes depression subscales after covariate adjustments. Follow-up analyses investigated non-elevated and elevated depressive symptom groups. We found inverse relationships between specific subscales (Subjective Depression and Mental Dullness) and attentional control. No significant relationships were evident for total depressive symptoms or for the group analyses. Findings suggest weak associations between depressive symptoms and cognition in young to middle-aged men without clinical depression, which adds to the literature on inconsistent findings in depressive symptom-cognition relationships.

Electroconvulsive therapy (ECT) for moderate-severity major depression among the elderly: Data from the pride study

BACKGROUND

Electroconvulsive therapy (ECT) is usually reserved for treatment of severe major depressive disorder (MDD), but may be equally effective in the treatment of moderate-severity MDD. This possibility, however, has only been studied to a very limited extent. We therefore investigated the efficacy of ECT after stratifying patients into severe MDD and moderate-severity MDD.

METHODS

We used data from the Prolonging Remission in Depressed Elderly (PRIDE) study, in which 240 patients (≥60 years) with MDD were treated with right unilateral ultrabrief pulse ECT, combined with venlafaxine. We used the six-item core depression subscale (HAM-D₆) of the Hamilton Depression Rating Scale to define depression severity. Participants with baseline total scores ≥12 on the HAM-D₆ were considered to have severe MDD, while those with HAM-D₆ total scores <12 were considered to have moderate-severity MDD.

RESULTS

Among the participants with severe MDD and moderate-severity MDD, the mean change in the HAM-D₆ total score from baseline to endpoint was -8.2 (95% confidence interval (95%CI) = -7.5; -9.0, paired t-test: p < 0.001) and -5.9 (95%CI = -5.1; -6.6, paired t-test: p < 0.001), respectively. A total of 63% of those with severe MDD and 75% of those with moderate-severity MDD achieved remission (HAM-D₆ total score ≤4) (Pearson's 2-sample chi-squared test of difference between groups: p = 0.27).

LIMITATIONS

The PRIDE study was not designed to address this research question.

CONCLUSIONS

ECT combined with venlafaxine appears to be an effective treatment for moderate-severity MDD. It may be appropriate to expand the indications for ECT to include patients with moderate-severity MDD.

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.