Does antidepressant therapy improve cognition in elderly depressed patients?

The multifaceted effects of fluoxetine treatment on cognitive functions

Fluoxetine, the prototypical selective serotonin reuptake inhibitor (SSRI), is widely used to treat major depressive disorder (MDD) and a variety of other central nervous system conditions, primarily due to its established clinical safety profile. Although its efficacy in treating depression is well-recognized, the impact of fluoxetine on cognitive functions remains inconsistent and elusive. In this review, we first examine the well-substantiated biological mechanisms underlying fluoxetine's antidepressant effects, which include serotonin reuptake inhibition and activation of TrkB receptors-key to brain-derived neurotrophic factor (BDNF) signaling. Subsequently, we delve into the cognitive side effects observed in both preclinical and clinical studies, affecting domains such as memory, attention, and executive functions. While certain studies indicate cognitive improvements in patients with underlying disorders, there is also evidence of negative effects, influenced by variables like gender, duration of treatment, age, disease pathology, and the specifics of cognitive testing. Significantly, the negative cognitive outcomes reported in preclinical research often involve healthy, non-diseased animals. This review underscores the necessity for heightened caution in fluoxetine prescription and further investigation into its potentially detrimental cognitive effects, even when used prophylactically.

Cognitive Outcomes After Antidepressant Pharmacotherapy for Late-Life Depression: A Systematic Review and Meta-Analysis

OBJECTIVE

The authors evaluated whether treatment of late-life depression (LLD) with antidepressants leads to changes in cognitive function.

METHODS

A systematic review and meta-analysis of prospective studies of antidepressant pharmacotherapy for adults age 50 or older (or mean age of 65 or older) with LLD was conducted. MEDLINE, EMBASE, and PsycInfo were searched through December 31, 2022. The primary outcome was a change on cognitive test scores from baseline to after treatment. Secondary outcomes included the effects of specific medications and the associations between changes in depressive symptoms and cognitive test scores. Participants with bipolar disorder, psychotic depression, dementia, or neurological disease were excluded. Findings from all eligible studies were synthesized at a descriptive level, and a random-effects model was used to pool the results for meta-analysis.

RESULTS

Twenty-two studies were included. Thirteen of 19 studies showed an improvement on at least one cognitive test after antidepressant pharmacotherapy, with the most robust evidence for the memory and learning (nine of 16 studies) and processing speed (seven of 10 studies) domains and for sertraline (all five studies). Improvements in depressive symptoms were associated with improvement in cognitive test scores in six of seven relevant studies. The meta-analysis (eight studies; N=493) revealed a statistically significant overall improvement in memory and learning (five studies: effect size=0.254, 95% CI=0.103-0.404, SE=0.077); no statistically significant changes were seen in other cognitive domains. The evaluated risk of publication bias was low.

CONCLUSION

Antidepressant pharmacotherapy of LLD appears to improve certain domains of cognitive function, particularly memory and learning. This effect may be mediated by an improvement in depressive symptoms. Studies comparing individuals receiving pharmacotherapy with untreated control participants are needed.

Association Between Mental Health Burden, Clinical Presentation, and Outcomes in Individuals With Symptomatic Peripheral Artery Disease: A Scientific Statement From the American Heart Association

Along with the rising burden of peripheral artery disease (PAD), mental health concerns are increasingly being recognized as a comorbidity to address in the chronic disease management of symptomatic PAD. Apart from a high prevalence of comorbid mental health conditions, the role of pain and changing health behaviors and the broader impacts of illness and adaptation to living with PAD require specialized behavioral health expertise. This scientific statement builds a case that this expertise should be integrated within the multidisciplinary PAD team. Furthermore, areas such as cognitive dysfunction and palliative care are highlighted as needing psychological interventions. Although much of the evidence of the efficacy of psychological and psychotropic interventions has been extrapolated from other cardiovascular populations, evidence for the role of psychological interventions for behavior change, for example, uptake of exercise regimens, is increasingly being accrued within PAD. Areas for behavioral health needs and interactions with PAD treatment are discussed, including the use of opioids, depression management, anxiety and stress reduction interventions, the use of benzodiazepines and antidepressants, smoking cessation, rehabilitation trajectories after amputation, and the role of cognitive decline for PAD treatment and outcomes. A case summary highlights the stigma around mental health and vascular disease and the fragmentation of care. This scientific statement provides remarks for building a road map for integrated behavioral PAD care and potential solutions to overcome these barriers. Instrumental to reaching these changes are interprofessional advocacy efforts and initiatives that help break down the stigma around mental health and promote evidence-based collaborative, nonhierarchical, and multidisciplinary PAD care.

Association between Antidepressants and Dementia Risk in Older Adults with Depression: A Systematic Review and Meta-Analysis

Depression, commonly treated with antidepressants, is associated with an increased risk of dementia, especially in older adults. However, the association between antidepressant use and dementia risk is unclear. We searched for randomized controlled trials and observational studies from PubMed, Embase, and Cochrane on 1 February 2022, restricting to full texts in English. Since dementia is a chronic disease requiring a long induction time, we restricted studies with ≥1 year follow-up. We extracted the relative risk (RR) adjusted for the most variables from each study and evaluated the heterogeneity using I square (I2). The protocol was registered in the PROSPERO International Register of Systematic Reviews (CRD42022338038). We included six articles in the systematic review, of which the sample size ranged from 716 to 141,740, and the median length of follow-up was 5 years. The pooled RR was 1.21 (95% CI = 1.12-1.29) with an I2 of 71%. Our findings suggest that antidepressant use was associated with an increased risk of dementia in older adults with depression, yet moderate to high heterogeneity existed across studies. Future work accounting for the depression progression is needed to differentiate the effect of depression and antidepressants on dementia risk.

Cold Cognition as Predictor of Treatment Response to rTMS; A Retrospective Study on Patients With Unipolar and Bipolar Depression

Background

Cognitive impairments are prevalent in patients with unipolar and bipolar depressive disorder (UDD and BDD, respectively). Considering the fact assessing cognitive functions is increasingly feasible for clinicians and researchers, targeting these problems in treatment and using them at baseline as predictors of response to treatment can be very informative.

Method

In a naturalistic, retrospective study, data from 120 patients (Mean age: 33.58) with UDD (n = 56) and BDD (n = 64) were analyzed. Patients received 20 sessions of bilateral rTMS (10 Hz over LDLPFC and 1 HZ over RDLPFC) and were assessed regarding their depressive symptoms, sustained attention, working memory, and executive functions, using the Beck Depression Inventory (BDI-II) and Neuropsychological Test Automated Battery Cambridge, at baseline and after the end of rTMS treatment course. Generalized estimating equations (GEE) and logistic regression were used as the main statistical methods to test the hypotheses.

Results

Fifty-three percentage of all patients (n = 64) responded to treatment. In particular, 53.1% of UDD patients (n = 34) and 46.9% of BDD patients (n = 30) responded to treatment. Bilateral rTMS improved all cognitive functions (attention, working memory, and executive function) except for visual memory and resulted in more modulations in the working memory of UDD compared to BDD patients. More improvements in working memory were observed in responded patients and visual memory, age, and sex were determined as treatment response predictors. Working memory, visual memory, and age were identified as treatment response predictors in BDD and UDD patients, respectively.

Conclusion

Bilateral rTMS improved cold cognition and depressive symptoms in UDD and BDD patients, possibly by altering cognitive control mechanisms (top-down), and processing negative emotional bias.

Prediction of Antidepressant Efficacy by Cognitive Function in First-Episode Late-Life Depression: A Pilot Study

The response rate of treatment for late-life depression (LLD) is only 25-60%. The cognitive impairment associated with LLD often affects the effectiveness of antidepressants and may has the potential ability to predict response. This study seeks a biomarker for baseline cognitive function to predict efficacy of antidepressants. Sixty patients diagnosed with LLD received escitalopram or sertraline treatment for 8 weeks. Clinical symptom was measured using Hamilton Depression Rating Scale-17 (HAMD-17) and cognitive function was measured using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Trail Making Test (TMT) before and after 8-week treatment. Patients were divided into treatment effective group (TE) and treatment ineffective group (TI) according to reduction rate in scores of HAMD-17 after treatment. Thirty-eight matched healthy controls (HC) were assessed using RBANS and TMT. There was significant decrease of score of RBANS and increase of score of TMT in patients with LLD compared with HC. Regression analysis revealed that change in HAMD-17 score was significantly positively associated with baseline score of picture naming, figure copy, digit span, and delayed memory. The preliminary findings suggested that working memory, attention, visuospatial, language function, and delayed memory should be examined further as a means of providing the useful objective biomarkers of treatment response.

CLINICAL TRIALS REGISTRATION

[www.ClinicalTrials.gov], identifier [ChiCTR2100042370].

Baseline predictors of cognitive change in the treatment of major depressive episode: systematic review

BACKGROUND

Cognitive impairment is a core feature of depression and has a negative effect on a person's functioning, in psychosocial and interpersonal areas, and on workforce performance. Cognitive impairment often persists, even with the remittance of mood symptoms. One potential way of improving treatment of cognitive impairment would be to identify variables that predict cognitive change in patients with depression.

AIMS

To systematically examine findings from studies that investigate baseline variables and how they predict, or correlate with, cognitive change in mood disorders, and to examine methodological issues from these studies.

METHOD

Studies that directly measured associations between at least one baseline variable and change in cognitive outcome in patients with current major depressive episode were identified using PubMed and Web of Science databases. Narrative review technique was used because of the heterogeneity of patient samples, outcome measures and study procedures. The review was registered on PROSPERO with registration number CRD42020150975.

RESULTS

Twenty-four studies met the inclusion criteria. Evidence from the present review for prediction of cognitive change from baseline variables was limited for demographic factors, with some preliminary evidence for depression, cognitive and biological factors. Identification of patterns across studies was difficult because of methodological variability across studies.

CONCLUSIONS

Findings from the present review suggest there may be some baseline variables that are useful in predicting cognitive change in mood disorders. This is an area warranting further research focus.

Association between dementia and depression: a retrospective study using the Korean National Health Insurance Service-National Sample Cohort database

OBJECTIVES

Dementia is common in people over the age of 65 years, with 80% of people with dementia older than 75 years. Previous studies have linked dementia to late-life depression, but the association between dementia and mid-life depression is poorly understood. Depression is a preventable and treatable medical condition, which means it is a modifiable factor that can potentially prevent or delay dementia. This study aimed to identify the association between dementia and depression within the life course.

DESIGN

A nationwide, retrospective propensity score matched cohort study associating dementia with depression. Depression diagnosed between the ages of 45 and 64 years was classified as 'mid-life' and 'late-life' if diagnosed at 65 years or older. Patients were considered to have depression when one or more International Statistical Classification of Diseases and Related Health Problems, 10th revision codes for depression were recorded as primary or secondary diagnosis.

SETTING

National Health Insurance Service-National Sample Cohort database of the National Health Insurance Service in South Korea, containing patient data from 2002 to 2013.

PARTICIPANTS

The study included 1824 and 374 852 patients in the case and control groups, respectively. A logistic regression analysis with complex sampling design was performed after adjusting for covariates, using the propensity score matching method without callipers, with a 1:1 nearest neighbour matching algorithm.

PRIMARY AND SECONDARY OUTCOME MEASURES

The association of mid-onset and late-onset depression with dementia in terms of sociodemographic characteristics, such as sex and age, within the Korean population.

RESULTS

Dementia was significantly associated with the presence of depression (OR=2.20, 95% CI=1.53-3.14); in particular, female patients with depression and patients aged 45-64 years with depression had increased odds of dementia (OR=2.65, 95% CI=1.78-3.93 and OR=2.72, 95% CI=1.41-5.24, respectively) CONCLUSION: Depression is an associated factor for dementia, especially among people aged 45-64 years (mid-life).

Antidepressant and anti-amnesic effects of the aqueous lyophilisate of the leaves of Leptadenia arborea on an animal model of cognitive deficit associated depression

Leptadenia arborea (Asclepiadaceae) is a plant used in traditional medicine to treat syphilis, migraine, and mental illnesses. The aim of our study was to investigate possible antidepressant and anti-amnesic effects of the aqueous lyophilisate of the leaves of Leptadenia arborea in an animal model of cognitive deficit associated depression. Swiss albino adult mice of both sexes were used for this study. A 14-day combined stress model was used to induce depression with early cognitive deficits. The forced swimming test, the open field test and plasma corticosterone level were used to assess antidepressant-like effect. The novel object recognition task (NORT), the Morris Water Maze (MWM) and neurochemical analysis of hippocampal acetylcholinesterase activity was also carried out to assess memory integrity. The aqueous lyophelisate of L. arborea increased swimming time and decreased immobility time in the forced swimming test. In the open field test they was no difference in the number of lines crossed between groups, and the lyophilisate-treated mice spent more time in the centre compared to the control. The lyophilisate decreased the plasma level of corticosterone compared to the control. The lyophilisate decreased the latency to reach the hidden platform and increased the time spent in the target quadrant in the MWM. The lyophilisate also increased the time of exploration of the novel object in the NORT and decreased the acetylcholinesterase activity in the hippocampus. L. arborea effects were decreased when it was co-administered with pCPA. Results suggest that the aqueous lyophilisate of the leaves of L. arborea possess antidepressant-like and anti-amnesic effects.

Depression, cognitive, and functional outcomes of Problem Adaptation Therapy (PATH) in older adults with major depression and mild cognitive deficits

OBJECTIVES

Antidepressants have limited efficacy in older adults with depression and cognitive impairment, and psychosocial interventions for this population have been inadequately investigated. Problem Adaptation Therapy (PATH) is a psychosocial intervention for older adults with major depression, cognitive impairment, and disability.

DESIGN

This study tests the efficacy of PATH versus Supportive Therapy for Cognitively Impaired Older Adults (ST-CI) in reducing depression (Montgamery Asberg Depression Rating Scale [MADRS]) and disability (World Health Organization Disability Assessments Schedule-II [WHODAS-II]) and improving cognitive outcomes (Mini Mental State Examination [MMSE]) over 24 weeks (12 weeks of treatment and 12-week post-treatment follow-up).

SETTING

Participants were recruited through collaborating community agencies of Weill Cornell Institute of Geriatric Psychiatry. Both interventions and all research assessments were conducted at home.

PARTICIPANTS

Thirty-five older adults (age ≥ 65 years) with major depression and cognitive impairment no dementia (CIND).

INTERVENTIONS

PATH aims to increase emotion regulation by incorporating a problem-solving approach, teaching compensatory strategies, and inviting caregiver participation. Supportive Therapy aims to facilitate the expression of affect, as well as promote empathy.

MEASUREMENTS

Depression was measured using the MADRS, disability using the WHODAS-II, and cognition using the MMSE.

RESULTS

PATH participants showed significantly greater reduction in MADRS total score (7.04 points at 24 weeks, treatment group by time interaction: F[1,24.4] = 7.61, p = 0.0108), greater improvement in MMSE total score (2.30 points at 24 weeks, treatment group by time interaction: F[1,39.8] = 13.31, p = 0.0008), and greater improvement in WHODAS-II total score (2.95 points at 24 weeks, treatment group by time interaction: F[1,89] = 4.93, p = 0.0290) than ST-CI participants over the 24-week period.

CONCLUSIONS

PATH participants had better depression, cognitive, and disability outcomes than ST-CI participants over 6 months. PATH may provide relief to depressed older adults with CIND who currently have limited treatment options.

Latent Classes of Cognitive Functioning Among Depressed Older Adults Without Dementia

OBJECTIVE

Use latent class analysis (LCA) to identify patterns of cognitive functioning in a sample of older adults with clinical depression and without dementia and assess demographic, psychiatric, and neurobiological predictors of class membership.

METHOD

Neuropsychological assessment data from 121 participants in the Alzheimer's Disease Neuroimaging Initiative-Depression project (ADNI-D) were analyzed, including measures of executive functioning, verbal and visual memory, visuospatial and language functioning, and processing speed. These data were analyzed using LCA, with predictors of class membership such as depression severity, depression and treatment history, amyloid burden, and APOE e4 allele also assessed.

RESULTS

A two-class model of cognitive functioning best fit the data, with the Lower Cognitive Class (46.1% of the sample) performing approximately one standard deviation below the Higher Cognitive Class (53.9%) on most tests. When predictors of class membership were assessed, carrying an APOE e4 allele was significantly associated with membership in the Lower Cognitive Class. Demographic characteristics, age of depression onset, depression severity, history of psychopharmacological treatment for depression, and amyloid positivity did not predict class membership.

CONCLUSION

LCA allows for identification of subgroups of cognitive functioning in a mostly cognitively intact late life depression (LLD) population. One subgroup, the Lower Cognitive Class, more likely to carry an APOE e4 allele, may be at a greater risk for subsequent cognitive decline, even though current performance on neuropsychological testing is within normal limits. These findings have implications for early identification of those at greatest risk, risk factors, and avenues for preventive intervention.

The relationship between depression and cognitive function in adults with cardiovascular risk: Evidence from a randomised attention-controlled trial

Background and aim

This study assessed the association between depressive symptom severity and cognition in middle-to-older aged adults with mild-to-moderate depression and cardiovascular risk factors using an online test battery (CogState) and whether changes in depressive symptoms over 3 months were associated with changes in cognition.

Methods

Participants (mean age = 57.8) with cardiovascular risk and mild–to-moderate depressive symptoms completed measures of psychomotor speed, learning, and executive function prior to (n = 445)_and after (n = 334) online depression or attention control interventions. The symptom severity-cognition relationship was examined both cross-sectionally and prospectively.

Results

Participants exhibited significantly reduced psychomotor speed and variable impairments on measures of learning and executive functioning relative to normative data. However, there was no association of depression severity with cognition at baseline or of change in depressive symptoms with change in cognitive performance.

Limitations

Participants were well-educated, which may have protected against cognitive decline. Attrition may limit generalisability, though is unlikely to explain the lack of association between depression symptoms and cognition.

Conclusions

Adults with comorbid mild-to-moderate depressive symptoms and cardiovascular risks performed less well than age-matched normative data on three online cognitive tests; however, we were unable to show any symptom-cognition association cross-sectionally or longitudinally, despite significant improvements in depressive symptoms. This challenges the generalisability of such associations found in more severely unwell clinical samples to those with a broader depressive symptom profile, or suggests that underlying cardiovascular disease may account for the association seen in some clinical studies. This has implications for scaling up selective prevention of cognitive decline.

Does the 5-HT1A rs6295 polymorphism influence the safety and efficacy of citalopram therapy in the oldest old?

Major depressive disorder (MDD) in older people is a relatively common, yet hard to treat problem. In this study, we aimed to establish if a single nucleotide polymorphism in the 5-HT_1A receptor gene (rs6295) determines antidepressant response in patients aged > 80 years (the oldest old) with MDD. Nineteen patients aged at least 80 years with a new diagnosis of MDD were monitored for response to citalopram 20 mg daily over 4 weeks and genotyped for the rs6295 allele. Both a frequentist and Bayesian analysis was performed on the data. Bayesian analysis answered the clinically relevant question: 'What is the probability that an older patient would enter remission after commencing selective serotonin reuptake inhibitor (SSRI) treatment, conditional on their rs6295 genotype?' Individuals with a CC (cytosine-cytosine) genotype showed a significant improvement in their Geriatric Depression Score (p = 0.020) and cognition (p = 0.035) compared with other genotypes. From a Bayesian perspective, we updated reports of antidepressant efficacy in older people with our data and calculated that the 4-week relative risk of entering remission, given a CC genotype, is 1.9 [95% highest-density interval (HDI) 0.7-3.5], compared with 0.52 (95% HDI 0.1-1.0) for the CG (cytosine-guanine) genotype. The sample size of n = 19 is too small to draw any firm conclusions, however, the data suggest a trend indicative of a relationship between the rs6295 genotype and response to citalopram in older patients, which requires further investigation.

(R)-fluoxetine enhances cognitive flexibility and hippocampal cell proliferation in mice

Fluoxetine is a clinically successful antidepressant. It is a racemic mixture of (R) and (S) stereoisomers. In preclinical studies, chronic treatment with fluoxetine (10 mg/kg) had antidepressant effects correlated with increased hippocampal cell proliferation in adult rodents. However, the contribution of the enantiomers of fluoxetine is largely unknown. We investigated the effects of treatment with (R)- and (S)-fluoxetine on cognitive behavioral paradigms and examined cell proliferation in the hippocampus of C57BL/6J female mice. In a behavioral sequencing task using the IntelliCage system in which discriminated spatial patterns of rewarded and never-rewarded corners were reversed serially, (R)-fluoxetine-treated mice showed rapid acquisition of behavioral sequencing (compared with S-fluoxetine) and cognitive flexibility in subsequent reversal stages in intra- and inter-session analysis. (R)-fluoxetine also increased cell proliferation in the hippocampus, in particular in the suprapyramidal blade of the dentate gyrus. (R)-fluoxetine had superior effects to (S)-fluoxetine in elevated plus maze, forced-swim and tail-suspension tests. These results suggest that (R)-fluoxetine, which has been reported to have a shorter half-life than (S)-fluoxetine, has superior antidepressant effects and more consistently improves spatial learning and memory. This profile offers advantages in depression treatment and may also aid management of the neurocognitive impairments associated with depression.

A Systematic Review of Cognitive Predictors of Treatment Outcome in Major Depression

Background: Research suggests that only 50% of patients with major depression respond to psychotherapy or pharmacological treatment, and relapse is common. Therefore, there is interest in elucidating factors that help predict clinical response. Cognitive impairment is a key feature of depression, which often persists beyond remission; thus, the aim of this systematic review was to determine whether baseline cognitive functioning can predict treatment outcomes in individuals with depression. Method: Studies examining cognitive predictors of treatment response in depression were identified using Pub Med and Web of Science databases. Given the heterogeneity of outcome measures, the variety of treatment protocols, and the differing ways in which data was presented and analyzed, a narrative rather than meta-analytic review technique was used. Results: 39 studies met inclusion criteria. Findings in younger adult samples were inconclusive. There was some evidence for a predictive effect of executive function and to a lesser extent, psychomotor speed, on treatment response. There was no evidence of learning or memory being associated with treatment response. In older-aged samples, the evidence was much more consistent, suggesting that poor executive function predicts poor response to SSRIs. Conclusions: Findings from the present review suggest that certain aspects of cognitive functioning, particularly executive function, may be useful in predicting treatment response in depression. This is certainly the case in elderly samples, with evidence suggesting that poor executive functioning predicts poor response to SSRIs. With further research, baseline cognitive functioning may serve as a factor which helps guide clinical decision making. Moreover, cognitive deficits may become targets for specific pharmacological or psychological treatments, with the hope of improving overall outcome.

Assessment and Management of Cognitive and Psychosocial Dysfunctions in Patients With Major Depressive Disorder: A Clinical Review

Background: Full functional recovery is defined as a state in which patients are again able to enjoy their usual activities, return to work, and take care of themselves, and it should represent the end goal of treatment in patients with major depressive disorder (MDD). Patients with MDD report many unmet needs, including residual cognitive symptoms, lack of improvement in psychosocial functioning and life satisfaction, even during mood symptom remission. In this paper, we aim to: (a) identify the available assessment tools for evaluating cognitive and psychosocial functioning in patients with MDD; (b) provide an overview of therapeutic options that can improve full functional recovery in MDD also by improving cognitive symptoms. Methods: The relevant databases MEDLINE, ISI Web of Knowledge - Web of Science Index, Cochrane Reviews Library and PsychoINFO were searched for identifying papers on validated tools for the assessment of cognitive and personal functioning in patients with MDD. Results: New assessment tools (such as the THINC-it TOOL, the COBRA, the SCIP-D, and the UPSA-D) have been developed for evaluating the cognitive dysfunction in MDD patients. Adopting these tools in the clinical routine practice is useful to evaluate the improvement in cognitive functioning and, therefore, the achievement of full functioning recovery. The optimal management of patients with MDD include the combination of pharmacological compounds and psychosocial interventions for achieving full functional recovery in patients with MDD. Conclusions: Full functional recovery must be the target of any treatment programme for patients with MDD. In order to achieve this goal, it is necessary to develop personalized treatment and integrate psychosocial and psychopharmacological interventions.

Post-stroke Fatigue and Depressive Symptoms Are Differentially Related to Mobility and Cognitive Performance

Background: Fatigue and depressive symptoms are common and often inter-related stroke sequelae. This study investigates how they are related, directly or indirectly, to mobility and cognitive outcomes within 6 months of stroke.

Methods: Participants were recruited from 4 stroke centers in Ontario, Canada. Post-stroke fatigue was assessed using the Fatigue Assessment Scale (FAS). Depressive symptoms were screened using the Center for Epidemiological Studies Scale for Depression (CES-D). Factor analyses were used to construct scores from mobility (distance traveled during a 2-min walk test, Chedoke-McMaster Stroke Assessment leg score, and Berg Balance Scale total score) and cognitive (Montreal Cognitive Assessment, Trail-Making Tests A and B, and five-word free recall) tests. Direct associations were assessed in linear regression models and indirect effects were assessed in path models. Covariates were age, sex, education, antidepressant use, days since stroke, and stroke severity (National Institute of Health Stroke Severity Scale score).

Results: Fatigue and depressive symptoms were highly correlated (r > 0.51, p < 0.0001). Depressive symptoms were associated with cognition (β = −0.184, p = 0.04) and indirectly with mobility, mediated by fatigue (indirect effect = −0.0142, 95% CI: −0.0277 to −0.0033). Fatigue was associated with mobility (β = −0.253, p = 0.01), and indirectly with cognition, mediated by depressive symptoms (indirect effect = −0.0113, 95% CI: −0.0242 to −0.0023).

Conclusions: Fatigue and depressive symptoms are related distinctly to cognitive and mobility impairments post-stroke. Fatigue was associated with poorer lower limb motor function, and with cognition indirectly via depressive symptoms.

Improvement in Depression is Associated with Improvement in Cognition in Late-Life Psychotic Depression

OBJECTIVE

To characterize cognitive function at baseline and investigate the relationship between change in cognition, depression, and psychosis after treatment among older adults with major depressive disorder with psychotic features.

METHODS

This was a secondary analysis of a double-blind, randomized, controlled treatment trial at inpatient and outpatient settings at four academic health centers on "Young Old" (aged 60-71 years, N = 71) and "Older" (aged 72-86 years, N = 71) participants diagnosed with psychotic depression. Olanzapine plus sertraline or olanzapine plus placebo were given until week 12 or termination.

RESULTS

At baseline, Young Old and Older participants did not differ on measures of depression severity or global cognition, information processing speed, and executive function. Improvement in depressive and psychotic symptoms from baseline to treatment end was similar in both the Young Old and Older groups. However, improvement in depressive symptoms was significantly associated with improvement in global cognitive function in Young Old participants but not in Older participants.

CONCLUSION

Cognitive dysfunction was not a detriment to improvement in symptoms of psychotic major depression in our geriatric patients. Young Old and Older patients improved to a similar degree on measures of depression and delusions from baseline to treatment end. However, improvement in cognition over the course of treatment was more prominent in the Young Old group than in the Older group.

Effects of Anodal Transcranial Direct Current Stimulation and Serotonergic Enhancement on Memory Performance in Young and Older Adults

In the absence of effective therapies for dementia and its precursors, enhancing neuroplasticity by means of non-invasive brain stimulation such as anodal transcranial direct current stimulation (atDCS) might be a promising approach to counteract or delay the onset of cognitive decline, but effect sizes have been moderate so far. Previous reports indicate that increasing serotonin levels may enhance atDCS-induced neuroplasticity. However, evidence for serotonergic modulation of atDCS effects on memory is still lacking. Here, we conducted a double-blind, randomized, sham-/placebo-controlled trial to investigate the impact of a selective serotonin reuptake inhibitor (SSRI; single dose of 20 mg citalopram) and atDCS over the right temporoparietal cortex (1 mA, 20 min) on memory formation. Twenty young and 20 older subjects completed an object-location learning task in each of the four conditions: sham+placebo, sham+SSRI, atDCS+placebo, and atDCS+SSRI. Outcome measures were performance in immediate (primary outcome) and delayed cued recall. While we found an SSRI effect, but no statistically significant effect of atDCS on immediate recall scores, young and older adults benefited most from the combined application (comparisons: atDCS+SSRI>atDCS+placebo and atDCS+SSRI>sham+placebo). Thus, our data provide evidence that atDCS improves memory formation if serotonergic neurotransmission is enhanced simultaneously. Further studies are needed to assess whether these findings extend to clinical populations with memory impairment and translate into clinically relevant improvements after long-term serotonergic enhancement and repeated stimulation.

The relationship among depression, subjective cognitive impairment, and neuropsychological performance in multiple sclerosis

The aim of this study was to examine, within the context of a treatment study, the relative contributions of depression and neuropsychological performance on patient ratings of cognitive functioning in a cohort of 58 moderately-depressed multiple sclerosis (MS) patients. All participants were randomized to one of three 16-week conventional treatments for depression. Assessments were conducted pre and post-treatment using: (1) Cognitive Function subscale of the Multiple Sclerosis Quality of Life-54 (MSQOL-54) to evaluate subjective cognitive impairment (SC), (2) Beck Depression Inventory (BDI), and (3) a neuropsychological index score (NP). Prior to treatment, 8% of the variance in SC was explained by NP, whereas 14% of the variance was explained by BDI, above and beyond NP. At post-treatment, patients were classified as ‘responders’ (BDI<11) and ‘nonresponders’ (BDI≥11). Among those participants classified as ‘responders’, NP accounted for 39% of the variance in SC, and BDI did not significantly predict SC. The results of this study suggest that depression may influence subjective reports of cognitive impairment, but these reports may not be reliably related to objective neuropsychological performance. Furthermore, patients may be more accurate reporters of their cognitive impairment after successful treatment for depression, suggesting that depression decreases the accuracy of patient reported cognitive impairment.

Systematic Review of Cognitive Effects of Electroconvulsive Therapy in Late-Life Depression

OBJECTIVE

Late-life depression (LLD) is known to negatively impact cognition even after remission of mood symptoms. Electroconvulsive therapy (ECT) and newer nonconvulsive electrical and magnetic brain stimulation interventions have been shown to have cognitive effects in patients with neuropsychiatric disorders.

METHODS

This review systematically assessed the effects of ECT on cognition in LLD. EMBASE, Ovid Medline, and PsycINFO were systematically searched through June 2015. The search was limited to publications from peer-reviewed journals in the English language.

RESULTS

A total of 5,154 publications was identified; 318 were reviewed in full text, of which 39 publications related to ECT were included. We focused this review only on ECT because evidence on newer interventions was deemed insufficient for a systematic review. This literature suggests increased rates of interictal and postictal cognitive decline with ECT but no long-term (i.e., 6 months or longer) deleterious effects on cognition. Instead, long-term cognitive outcomes with ECT have been reported as either not changed or improved. This literature favors nondominant unilateral ECT over bilateral ECT for cognition.

CONCLUSION

Published literature on brain stimulation interventions in LLD is mainly limited to ECT. This literature suggests that deleterious effects of ECT in LLD are limited and transient, with better cognitive outcomes with unilateral ECT. There is not enough evidence to fully characterize long-term deleterious effects of ECT or effects of newer brain stimulation techniques on cognition in LLD.

Neuropsychological functioning in the acute and remitted States of late-life depression

Late-life depression (LLD, major depression occurring in an adult 60 years or older) is a common condition that frequently presents with cognitive impairment. Up to half of individuals with LLD are estimated to have cognitive impairment greater than that of age- and education-matched comparators, with impairments of episodic memory, speed of information processing, executive functioning, and visuospatial ability being most common. To inform our understanding of the state- versus trait-effects of depression on neuropsychological functioning, and to overcome limitations of previous studies, we utilized baseline data from the longitudinal Pathways study to compare differences in single time point performance on a broad-based neuropsychological battery across three diagnostic groups of older adults, each comprised of unique participants (n = 438): currently depressed (n = 120), previously depressed but currently euthymic (n = 190), and never-depressed (n = 128). Consistent with our hypotheses, we found that participants with a history of depression (currently or previously depressed) performed significantly worse than never-depressed participants on most tests of global cognition, as well as on tests of episodic memory, attention and processing speed, verbal ability, and visuospatial ability; in general, differences were most pronounced within the domain of attention and processing speed. Contrary to our hypothesis, we did not observe differences in executive performance between the two depression groups, suggesting that certain aspects of executive functioning are "trait deficits" associated with LLD. These findings are in general agreement with the existing literature, and represent an enhancement in methodological rigor over previous studies given the cross-sectional approach that avoids practice effects on test performance.

A Meta-Analysis of Executive Dysfunction and Antidepressant Treatment Response in Late-Life Depression

OBJECTIVE

Depressed older adults with executive dysfunction (ED) may respond poorly to antidepressant treatment. ED is a multifaceted construct and different studies have measured different aspects of ED, making it unclear which aspects predict poor response. Meta-analytic methods were used to determine whether ED predicts poor antidepressant treatment response in late-life depression and to determine which domains of executive functioning are responsible for this relationship.

METHODS

A Medline search was conducted to identify regimented treatment trials contrasting executive functioning between elderly responders and nonresponders; only regimented treatment trials for depressed outpatients aged 50 and older were included. Following the most recent PRISMA guidelines, 25 measures of executive functioning were extracted from eight studies. Six domains were identified: cognitive flexibility, planning and organization, response inhibition, selective attention, verbal fluency, and the Dementia Rating Scale Initiation/Perseveration composite score (DRS I/P). Hedge's g was calculated for each measure of executive functioning. A three-level Bayesian hierarchical linear model (HLM) was used to estimate effect sizes for each domain of executive functioning.

RESULTS

The effect of planning and organization was significantly different from zero (Bayesian HLM estimate of domain effect size: 0.91; 95% CI: 0.32-1.58), whereas cognitive flexibility, response inhibition, selective attention, verbal fluency, and the DRS I/P composite score were not.

CONCLUSION

The domain of planning and organization is meaningfully associated with poor antidepressant treatment response in late-life depression. These findings suggest that therapies that focus on planning and organization may provide effective augmentation strategies for antidepressant nonresponders with late-life depression.

Utility of the Neurobehavioral Cognitive Status Examination (COGNISTAT) in differentiating between depressive states in late-life depression and late-onset Alzheimer's disease: a preliminary study

BACKGROUND

It is often difficult to differentiate between the depressive states seen in late-life depression and late-onset Alzheimer' disease (AD) in the clinical setting.

METHODS

Thirty-four outpatients were recruited, all fulfilling the criteria of aged 65 years or above, scores of 14 or more on the Hamilton depression rating scale (HAM-D), and 26 or less on the Mini-Mental State Examination (MMSE). At the initial visit, they were administered the Neurobehavioral Cognitive Status Examination (COGNISTAT). At 1 month, a diagnosis of either senile depression (n = 24) or Alzheimer' disease (n = 10) was made.

RESULTS

The COGNISTAT revealed that the late-life depression group showed significantly higher scores in orientation and comprehension subtests compared with the AD group. At the study endpoint (6 months after treatment), MMSE detected significant improvements in the late-life depression group (n = 15), but no changes in the late-onset AD group (n = 7). Scores for memory, similarities, and judgment on the second COGNISTAT were significantly improved in the depressed group, whereas calculation scores deteriorated significantly in the AD group.

CONCLUSION

The COGNISTAT could prove useful in differentiating late-life depression from late-onset AD, despite similar scores on MMSE.

Comparative Cognitive Profile of Second-Generation Antidepressants in Elderly Nursing Home Residents With Depression

BACKGROUND

Past literature suggests that the use of second-generation antidepressants improves cognition in depressed elderly patients.

OBJECTIVE

This study assessed the comparative cognitive profile of commonly used second-generation antidepressant classes in elderly residents with depression.

METHODS

A multiple propensity score adjusted retrospective cohort study was conducted using 2007-2010 Medicare Part D claims and Minimum Data Set (MDS). Elderly nursing home residents (65 years or older) with depression using a new prescription of selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), and tetracyclics constituted the study cohort. The outcome of interest was cognition, measured using the MDS Cognition Scale. Cognition was measured at each quarterly assessment after antidepressant initiation for a maximum of 1 year. The propensity score-adjusted repeated-measures mixed model was used to evaluate the comparative profile of SSRIs, SNRIs, and tetracyclics with respect to cognition.

RESULTS

The study cohort comprised 1518 elderly nursing home residents. Of these, 1081 received SSRIs (71.21%), 320 received tetracyclics (21.08%), and 117 received SNRIs (7.71%). The propensity score-adjusted repeated-measures mixed model did not show any statistically significant difference in cognition with the use of SSRIs (β = -0.14; 95% CI = -0.53, 0.25) or tetracyclics (β = -0.36; 95% CI = -0.80, 0.08) when compared with SNRIs, after controlling for other factors.

CONCLUSIONS

The cognitive effect of SSRIs, SNRIs, and tetracyclics was similar in elderly nursing home residents with depression. Further studies are needed to evaluate the long-term cognitive effects of second-generation antidepressants in this vulnerable population.

Cognitive functioning throughout the treatment history of clinical late-life depression

OBJECTIVE

Previous investigations into the relationship between late-life depressive symptoms and cognitive functioning have resulted in mixed findings concerning whether or not depressive symptoms and cognitive functioning are related. The mixed reports may be due in part to differences in clinical and nonclinical samples and to inadequate consideration of the dynamic nature (i.e., fluctuating course) of depressive symptoms and cognitive functioning in older adults. The current study examined the chronic, acute, and longitudinal relationships between depressive symptoms and cognitive functioning in older adults in an ongoing treatment study of major depressive disorder (MDD).

METHODS

The neurocognitive outcomes of depression in the elderly study operates in a naturalistic treatment milieu using a pharmacological treatment algorithm and regular psychiatric assessment. Four hundred and fifty-three older adults [mean age 70 years, standard deviation (SD) = 7.2] meeting criteria for MDD at study enrollment received annual neuropsychological testing and depressive symptom monitoring for an average of 8.5 years (SD = 4.5).

RESULTS

Hierarchical linear modeling revealed that higher age, lower education, and higher average/chronic levels of depressive symptoms were related to lower cognitive functioning. Additionally, results revealed that when an individual's depressive symptoms are higher than is typical for a specific individual, general cognitive function was worse than average. There was no evidence of lagged/longitudinal relationships between depressive symptoms and cognitive functioning in older adults in treatment for MDD.

CONCLUSIONS

Cognitive functioning and depressive symptoms are concurrently associated in older adults with MDD, highlighting the potential importance for stabilizing mood symptoms as a means to manage cognitive deficits in late-life depression.

Citalopram, methylphenidate, or their combination in geriatric depression: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

The authors evaluated the potential of methylphenidate to improve antidepressant response to citalopram, as assessed by clinical and cognitive outcomes, in elderly depressed patients.

METHOD

The authors conducted a 16-week randomized double-blind placebo-controlled trial for geriatric depression in 143 older outpatients diagnosed with major depression comparing treatment response in three treatment groups: methylphenidate plus placebo (N=48), citalopram plus placebo (N=48), and citalopram plus methylphenidate (N=47). The primary outcome measure was change in depression severity. Remission was defined as a score of 6 or less on the Hamilton Depression Rating Scale. Secondary outcomes included measures of anxiety, apathy, quality of life, and cognition.

RESULTS

Daily doses ranged from 20 mg to 60 mg for citalopram (mean=32 mg) and from 5 mg to 40 mg for methylphenidate (mean=16 mg). All groups showed significant improvement in depression severity and in cognitive performance. However, the improvement in depression severity and the Clinical Global Impressions improvement score was more prominent in the citalopram plus methylphenidate group compared with the other two groups. Additionally, the rate of improvement in the citalopram plus methylphenidate group was significantly higher than that in the citalopram plus placebo group in the first 4 weeks of the trial. The groups did not differ in cognitive improvement or number of side effects.

CONCLUSIONS

Combined treatment with citalopram and methylphenidate demonstrated an enhanced clinical response profile in mood and well-being, as well as a higher rate of remission, compared with either drug alone. All treatments led to an improvement in cognitive functioning, although augmentation with methylphenidate did not offer additional benefits.

Depression and dementias among military veterans

Depression is very common throughout the course of veterans' lives, and dementia is common in late life. Previous studies suggest an association between depression and dementia in military veterans. The most likely biologic mechanisms that may link depression and dementia among military veterans include vascular disease, changes in glucocorticoid steroids and hippocampal atrophy, deposition of β-amyloid plaques, inflammatory changes, and alterations of nerve growth factors. In addition, military veterans often have depression comorbid with posttraumatic stress disorder or traumatic brain injury. Therefore, in military veterans, these hypothesized biologic pathways going from depression to dementia are more than likely influenced by trauma-related processes. Treatment strategies for depression, posttraumatic stress disorder, or traumatic brain injury could alter these pathways and as a result decrease the risk for dementia. Given the projected increase of dementia, as well as the projected increase in the older segment of the veteran population, in the future, it is critically important that we understand whether treatment for depression alone or combined with other regimens improves cognition. In this review, we summarize the principal mechanisms of this relationship and discuss treatment implications in military veterans.

Cyr N, Lavretsky H. The patterns of cognitive and functional impairment in amnestic and non-amnestic mild cognitive impairment in geriatric depression

OBJECTIVES

Depressed older adults are at risk for the development of mild cognitive impairment (MCI), but few studies have characterized MCI subtypes in geriatric depression. The objective of this study was to identify the clinical patterns of MCI in late-life depression.

DESIGN

Baseline demographic, clinical, and neuropsychological test data collected as part of a randomized antidepressant trial for geriatric depression.

SETTING

UCLA-based outpatient clinic.

PARTICIPANTS

One hundred thirty-eight older adults with major depression.

MEASUREMENTS

A neuropsychological test battery and comprehensive evaluations of depression, apathy, quality of life, medical burden, and vascular risk factors.

RESULTS

Seventy-one participants (51%) had MCI and 67 (49%) were cognitively normal. Of subjects with MCI, 14 (20%) had amnestic MCI and 57 (80%) had non-amnestic MCI. Overall, patients with MCI had greater depression severity, poorer quality of life, and worse performance on the Mini-Mental State Exam than patients without MCI. Patients with non-amnestic MCI had significantly greater depression severity than patients without MCI. Across all subjects, depression severity correlated with impaired performance in language and visuospatial functioning.

CONCLUSION

Our findings suggest that MCI is associated with greater severity of depression, poorer quality of life, and worse global cognitive function. Overall, subtypes of MCI in geriatric depression differ in the patterns of functional impairment, which may require different therapeutic approaches.

Pharmacological and non-pharmacological interventions to improve cognitive dysfunction and functional ability in clinical depression--a systematic review

Cognitive dysfunction is of clinical significance and exerts longstanding implication on patients׳ function. Pharmacological and non-pharmacological treatments of cognitive dysfunction are emerging. This review evaluates pharmacological and non-pharmacological treatments of cognitive impairment primarily in the domains of memory, attention, processing speed and executive function in clinical depression. A total of 35 studies were retrieved from Pubmed, PsycInfo and Scopus after applying inclusion and exclusion criteria. Results show that various classes of antidepressants exert improving effects on cognitive function across several cognitive domains. Specifically, studies suggest that SSRIs, the SSRE tianeptine, the SNRI duloxetine, vortioxetine and other antidepressants such as bupropion and moclobemide may exert certain improving effects on cognitive function in depression, such as in learning and memory and executive function. Class-specific cognitive domains or specific dose-response relationships were not identified yet. The few non-pharmacological studies conducted employing cognitive orientated treatments and cognitive remediation therapy show promising results for the improvement of cognitive impairment in depression. However, several methodological constraints of studies limit generalizability of the results and caution the interpretation. Future direction should consider the development of a neuropsychological consensus cognitive battery to support the discovery, clinical assessment, comparison of studies and registration of new agents in clinical depression.

Cognitive functioning and late-life depression

This brief report provides an introduction to the topic of cognitive functioning in late-life depression (LLD). In addition to providing a review of the literature, we present a framework for understanding the heterogeneity of cognitive outcomes in this highly prevalent disorder. In addition, we discuss the relationship between LLD and dementia, and highlight the importance of regularly assessing cognitive functioning in older adults who present with depressive symptoms. If cognitive deficits are discovered during a neuropsychological assessment, we recommend referral to a geriatric psychiatrist or cognitive neurologist, for evaluation and treatment of the patient's symptoms.

Cognition in Late Life Depression: Treatment Considerations

Late life depression (LLD) frequently presents with cognitive impairment, and growing evidence suggests that these disease processes are "linked" in multiple ways. For some individuals, LLD may be a recurrence of a long-standing depressive illness, while for others it may be the leading symptom of a developing neuropathological disorder. Overall, studies investigating the relationship between treatment of LLD and improvement in cognitive functioning have yielded mixed results. Research suggests that a subset of individuals with LLD and cognitive dysfunction will experience an improvement in cognitive function after antidepressant treatment, though a significant proportion will continue to exhibit cognitive impairment following resolution of their depressive symptoms. From a treatment standpoint, it is critical to ensure that an individual's depressive symptoms have been treated to remission, measured by a standardized rating scale such as the Geriatric Depression Scale (GDS). SSRI or SNRI monotherapy is often effective, and may be enhanced by employing an evidence-based psychotherapy such as Problem Solving Therapy (PST) or Interpersonal Therapy (IPT), modified to accommodate cognitive impairments that may be present. With respect to specific treatment of cognitive dysfunction, cognitive augmentation or training strategies can be helpful for some patients, and may be explored in combination with treatment of the primary depressive episode. While the introduction of a cholinesterase inhibitor (e.g. donepezil) may be considered, the potential benefit (modest improvement in cognition and functioning) must be weighed against an increased risk for worsening or recurrent depression. Finally, lifestyle factors-such as aerobic exercise, follow-up with a primary care physician for management of co-morbid medical illnesses, and regular participation in stimulating activities (such as through a senior center)-are important and should be included as part of the overall treatment plan.

The default mode network may be the key substrate of depressive symptom-related cognitive changes

Depressive symptoms are associated with an increased risk of Alzheimer's disease (AD) but the mechanism(s) involved has not been well established. In a convenience sample of participants in the University of Kansas' Brain Aging Project, we use structural equation modeling (SEM) to explicitly distinguish depressive symptom-related variance in cognitive task performance (i.e., DEPCOG) from that which is unrelated to a depressive symptoms. DEPCOG is strongly associated with the cognitive correlates of functional status (δ), which we previously associated with elements of the Default Mode Network (DMN). Both δ and DEPCOG map to a posterior cingulate seeded network that has recently been associated with amyloid-β deposition and includes elements of the DMN. Both contribute significantly to clinical dementia status and dementia severity, as measured by the Clinical Dementia Rating Scale Sum of Boxes. These findings suggest that the cognitive correlates of depressive symptoms, even in the absence of a major depressive episode, may contribute to dementia in their own right, and could be responsible for some cases of incident clinical "AD". This conclusion suggests new opportunities for the latter's diagnosis, prevention, and treatment.

Fluoxetine versus other types of pharmacotherapy for depression

BACKGROUND

Depression is common in primary care and is associated with marked personal, social and economic morbidity, thus creating significant demands on service providers. The antidepressant fluoxetine has been studied in many randomised controlled trials (RCTs) in comparison with other conventional and unconventional antidepressants. However, these studies have produced conflicting findings.Other systematic reviews have considered selective serotonin reuptake inhibitor (SSRIs) as a group which limits the applicability of the indings for fluoxetine alone. Therefore, this review intends to provide specific and clinically useful information regarding the effects of fluoxetine for depression compared with tricyclics (TCAs), SSRIs, serotonin-noradrenaline reuptake inhibitors (SNRIs), monoamineoxidase inhibitors (MAOIs) and newer agents, and other conventional and unconventional agents.

OBJECTIVES

To assess the effects of fluoxetine in comparison with all other antidepressive agents for depression in adult individuals with unipolar major depressive disorder.

SEARCH METHODS

We searched the Cochrane Collaboration Depression, Anxiety and Neurosis Review Group Controlled Trials Register (CCDANCTR)to 11May 2012. This register includes relevant RCTs from the Cochrane Central Register of Controlled Trials (CENTRAL) (all years),MEDLINE (1950 to date), EMBASE (1974 to date) and PsycINFO (1967 to date). No language restriction was applied. Reference lists of relevant papers and previous systematic reviews were handsearched. The pharmaceutical company marketing fluoxetine and experts in this field were contacted for supplemental data.

SELECTION CRITERIA

All RCTs comparing fluoxetine with any other AD (including non-conventional agents such as hypericum) for patients with unipolar major depressive disorder (regardless of the diagnostic criteria used) were included. For trials that had a cross-over design only results from the first randomisation period were considered.

DATA COLLECTION AND ANALYSIS

Data were independently extracted by two review authors using a standard form. Responders to treatment were calculated on an intention-to-treat basis: dropouts were always included in this analysis. When data on dropouts were carried forward and included in the efficacy evaluation, they were analysed according to the primary studies; when dropouts were excluded from any assessment in the primary studies, they were considered as treatment failures. Scores from continuous outcomes were analysed by including patients with a final assessment or with the last observation carried forward. Tolerability data were analysed by calculating the proportion of patients who failed to complete the study due to any causes and due to side effects or inefficacy. For dichotomous data, odds ratios (ORs) were calculated with 95% confidence intervals (CI) using the random-effects model. Continuous data were analysed using standardised mean differences (SMD) with 95% CI.

MAIN RESULTS

A total of 171 studies were included in the analysis (24,868 participants). The included studies were undertaken between 1984 and 2012. Studies had homogenous characteristics in terms of design, intervention and outcome measures. The assessment of quality with the risk of bias tool revealed that the great majority of them failed to report methodological details, like the method of random sequence generation, the allocation concealment and blinding. Moreover, most of the included studies were sponsored by drug companies, so the potential for overestimation of treatment effect due to sponsorship bias should be considered in interpreting the results. Fluoxetine was as effective as the TCAs when considered as a group both on a dichotomous outcome (reduction of at least 50% on the Hamilton Depression Scale) (OR 0.97, 95% CI 0.77 to 1.22, 24 RCTs, 2124 participants) and a continuous outcome (mean scores at the end of the trial or change score on depression measures) (SMD 0.03, 95% CI -0.07 to 0.14, 50 RCTs, 3393 participants). On a dichotomousoutcome, fluoxetine was less effective than dothiepin or dosulepin (OR 2.13, 95% CI 1.08 to 4.20; number needed to treat (NNT) =6, 95% CI 3 to 50, 2 RCTs, 144 participants), sertraline (OR 1.37, 95% CI 1.08 to 1.74; NNT = 13, 95% CI 7 to 58, 6 RCTs, 1188 participants), mirtazapine (OR 1.46, 95% CI 1.04 to 2.04; NNT = 12, 95% CI 6 to 134, 4 RCTs, 600 participants) and venlafaxine(OR 1.29, 95% CI 1.10 to 1.51; NNT = 11, 95% CI 8 to 16, 12 RCTs, 3387 participants). On a continuous outcome, fluoxetine was more effective than ABT-200 (SMD -1.85, 95% CI -2.25 to -1.45, 1 RCT, 141 participants) and milnacipran (SMD -0.36, 95% CI-0.63 to -0.08, 2 RCTs, 213 participants); conversely, it was less effective than venlafaxine (SMD 0.10, 95% CI 0 to 0.19, 13 RCTs,3097 participants). Fluoxetine was better tolerated than TCAs considered as a group (total dropout OR 0.79, 95% CI 0.65 to 0.96;NNT = 20, 95% CI 13 to 48, 49 RCTs, 4194 participants) and was better tolerated in comparison with individual ADs, in particular amitriptyline (total dropout OR 0.62, 95% CI 0.46 to 0.85; NNT = 13, 95% CI 8 to 39, 18 RCTs, 1089 participants), and among the newer ADs ABT-200 (total dropout OR 0.18, 95% CI 0.08 to 0.39; NNT = 3, 95% CI 2 to 5, 1 RCT, 144 participants), pramipexole(total dropout OR 0.12, 95% CI 0.03 to 0.42, NNT = 3, 95% CI 2 to 5, 1 RCT, 105 participants), and reboxetine (total dropout OR0.60, 95% CI 0.44 to 0.82, NNT = 9, 95% CI 6 to 24, 4 RCTs, 764 participants).

AUTHORS' CONCLUSIONS

The present study detected differences in terms of efficacy and tolerability between fluoxetine and certain ADs, but the clinical meaning of these differences is uncertain.Moreover, the assessment of quality with the risk of bias tool showed that the great majority of included studies failed to report details on methodological procedures. Of consequence, no definitive implications can be drawn from the studies' results. The better efficacy profile of sertraline and venlafaxine (and possibly other ADs) over fluoxetine may be clinically meaningful,as already suggested by other systematic reviews. In addition to efficacy data, treatment decisions should also be based on considerations of drug toxicity, patient acceptability and cost.

Association between severity of depression and self-perceived cognitive difficulties among full-time employees

OBJECTIVE

To assess the relationship between self-perceived deficits in cognition and severity of depression reported by individuals in full-time employment.

METHOD

Individuals ≥ 18 years of age employed full-time with diagnosed depression excluding bipolar disorder (participants had to be told by a doctor that they had depression based on DSM-IV criteria) completed a 25-minute Web-based survey in February 2010 (study population identified by Harris Interactive, Rochester, New York). The survey used the Perceived Deficits Questionnaire (PDQ) to assess self-perceived cognitive impairment and the 9-item Patient Health Questionnaire (PHQ-9) to assess depression severity. The 20-question PDQ was used to assess self-perceived cognitive difficulties within the domains of prospective memory, retrospective memory, attention/concentration, and planning/organization (range, 0-20: higher scores indicate greater impairment). Subjects answered how often they experienced such difficulties during the previous 4 weeks (0 = never, 1 = rarely, 2 = sometimes, 3 = often, 4 = almost always). The scale ranges from 0-20 for each of the 4 subscales, with higher scores indicating greater cognitive impairment. The impact of depression on PDQ scores was assessed using a trend test based on an analysis of covariance controlling for potential confounders.

RESULTS

Subjects (N = 1,051) (58% women) had a mean ± SD age of 47 ± 12 years; 38% held professional employment. PHQ-9 scores indicated that 423 employees (40.3%) had no depressive symptoms at the time of the survey, 319 (30.4%) had mild depression, 166 (15.8%) had moderate depression, 82 (7.8%) had moderately severe depression, and 61 (5.8%) had severe depression. Perceived cognitive functioning worsened with increasing severity of depression symptoms (P < .0001) on the basis of PDQ scores. On the basis of responses to the PDQ, in the current study, most impairment was seen in the attention/concentration and planning/organization subscales in severely depressed subjects (12.2 for both) compared with those with no depressive symptoms (4.4 and 3.5, respectively), indicating more cognitive impairment in the severely depressed subjects compared to the subjects with no depression.

CONCLUSIONS

In currently employed individuals, self-perceived cognitive dysfunction worsened with increasing severity of depressive symptoms. This association was independent of antidepressant use. The greatest impairment in self-perceived cognition was observed in the planning/organization and attention/concentration subscales.

Change in cognitive functioning in depressed older adults following treatment with sertraline or nortriptyline

OBJECTIVE

The aim of this study was to compare the impact of nortriptyline to sertraline on change in cognitive functioning in depressed older adults.

METHODS

We used pre-post neuropsychological data collected as part of a 12-week medication trial comparing sertraline to nortriptyline in the treatment of older adults with non-psychotic, unipolar major depression to examine change in cognitive functioning. Neuropsychological assessments included mental status (Mini-Mental Status Exam), psychomotor speed (Purdue Pegboard), attention (Continuous Performance Test, Trail Making Test A), executive functioning (Stroop Color/word Test, Trail Making Test B), and memory (Buschke Selective Reminding Test).

RESULTS

Within treatment groups, patients treated with sertraline improved only on verbal learning. This change did not depend on responder status. Between treatment groups, patients treated with sertraline improved more in verbal learning compared with patients treated with nortriptyline. Looking at change in cognition as a function of medication condition and responder status revealed that sertraline responders improved more in verbal learning compared with nortriptyline responders but not more than sertraline non-responders or nortriptyline non-responders. Nortriptyline responders were the only treatment by responder status group to show no improvement in verbal learning from baseline to endpoint.

CONCLUSIONS

Unexpectedly, nortriptyline responders showed no improvement in verbal learning as compared with patients treated with sertraline or nortriptyline non-responders. However, given the small sample sizes and number of statistical tests (potential for type 1 error), replication is warranted.

Cognitive improvement following treatment in late-life depression: relationship to vascular risk and age of onset

OBJECTIVES

To test the hypothesis that the degree of vascular burden and/or age of onset may influence the degree to which cognition can improve during the course of treatment in late-life depression.

DESIGN

Measurement of cognition both before and following 12 weeks of treatment with sertraline.

SETTING

University medical centers (Washington University and Duke University).

PARTICIPANTS

One hundred sixty-six individuals with late-life depression.

INTERVENTION

Sertraline treatment.

MEASUREMENTS

The cognitive tasks were grouped into five domains (language, processing speed, working memory, episodic memory, and executive function). We measured vascular risk using the Framingham Stroke Risk Profile measure. We measured T2-based white matter hyperintensities using the Fazekas criteria.

RESULTS

Both episodic memory and executive function demonstrated significant improvement among adults with late-life depression during treatment with sertraline. Importantly, older age, higher vascular risk scores, and lower baseline Mini-Mental State Examination scores predicted less change in working memory. Furthermore, older age, later age of onset, and higher vascular risk scores predicted less change in executive function.

CONCLUSIONS

These results have important clinical implications in that they suggest that a regular assessment of vascular risk in older adults with depression is necessary as a component of treatment planning and in predicting prognosis, both for the course of the depression itself and for the cognitive impairments that often accompany depression in later life.

Chemocentric informatics approach to drug discovery: identification and experimental validation of selective estrogen receptor modulators as ligands of 5-hydroxytryptamine-6 receptors and as potential cognition enhancers

We have devised a chemocentric informatics methodology for drug discovery integrating independent approaches to mining biomolecular databases. As a proof of concept, we have searched for novel putative cognition enhancers. First, we generated Quantitative Structure-Activity Relationship (QSAR) models of compounds binding to 5-hydroxytryptamine-6 receptor (5-HT(6)R), a known target for cognition enhancers, and employed these models for virtual screening to identify putative 5-HT(6)R actives. Second, we queried chemogenomics data from the Connectivity Map ( http://www.broad.mit.edu/cmap/ ) with the gene expression profile signatures of Alzheimer's disease patients to identify compounds putatively linked to the disease. Thirteen common hits were tested in 5-HT(6)R radioligand binding assays and ten were confirmed as actives. Four of them were known selective estrogen receptor modulators that were never reported as 5-HT(6)R ligands. Furthermore, nine of the confirmed actives were reported elsewhere to have memory-enhancing effects. The approaches discussed herein can be used broadly to identify novel drug-target-disease associations.

Antidepressant use and cognitive deficits in older men: addressing confounding by indications with different methods

PURPOSE

Antidepressant use has been associated with cognitive impairment in older persons. We sought to examine whether this association might reflect an indication bias.

METHODS

A total of 544 community-dwelling hypertensive men aged ≥65 years completed the Hopkins Verbal Learning Test at baseline and 1 year. Antidepressant medications were ascertained by the use of medical records. Potential confounding by indications was examined by adjusting for depression-related diagnoses and severity of depression symptoms using multiple linear regression, a propensity score, and a structural equation model (SEM).

RESULTS

Before adjusting for the indications, a one unit cumulative exposure to antidepressants was associated with -1.00 (95% confidence interval [CI], -1.94, -0.06) point lower HVLT score. After adjusting for the indications using multiple linear regression or a propensity score, the association diminished to -0.48 (95% CI, -0.62, 1.58) and -0.58 (95% CI, -0.60, 1.58), respectively. The most clinical interpretable empirical SEM with adequate fit involves both direct and indirect paths of the two indications. Depression-related diagnoses and depression symptoms significantly predict antidepressant use (p < .05). Their total standardized path coefficients on Hopkins Verbal Learning Test score were twice (0.073) or as large (0.034) as the antidepressant use (0.035).

CONCLUSION

The apparent association between antidepressant use and memory deficit in older persons may be confounded by indications. SEM offers a heuristic empirical method for examining confounding by indications but not quantitatively superior bias reduction compared with conventional methods.

Antidepressant use and cognitive functioning in older medical patients with major or minor depression: a prospective cohort study with database linkage

OBJECTIVE

The long-term cognitive effect of antidepressant medications in older persons is not well understood, especially in those with minor depression and complex medical conditions. The objective of this study is to examine this relationship in older medical patients with different depression diagnoses.

METHODS

281 medical inpatients aged 65 years and older from 2 acute care hospitals in Montreal, Canada, were diagnosed as with major or minor depression or without depression according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria. They were followed up with the Mini-Mental State Examination for cognitive function and the Hamilton Depression Rating Scale for depressive symptoms at baseline and 3, 6, and 12 months after discharge. Antidepressant medication was ascertained from a provincial prescription database and quantified as cumulative exposures over each follow-up interval.

RESULTS

During the 12-month follow-up period, 1027 antidepressant prescriptions were filled. The most frequently prescribed antidepressant agents were citalopram (0.81 prescriptions per person), sertraline (0.76), and paroxetine (0.66). Antidepressant use was not associated with cognitive changes among patients with major depression or without depression but was associated with an increased Mini-Mental State Examination score in patients with minor depression (1.4 points; 95% confidence interval, 0.1-2.6), independent of change in the severity of depression symptoms, concomitant benzodiazepine or psychotropic drug use, and other potentially important confounders.

CONCLUSIONS

In this cohort of older medical patients, antidepressant use for 12 months did not lead to significant cognitive impairment. The small cognitive improvement among minor depression associated with antidepressant use deserves further investigation.