Effects of major depression on the cognitive function of younger and older subjects

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

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

Differences in cognitive functions of atypical and non-atypical depression based on propensity score matching

BACKGROUND

Clinical and etiological heterogeneity have hindered our understanding of depression, thus driving the studies of major depressive disorder (MDD) subtypes. Atypical depression (AD) is a subtype of MDD with atypical features. Cognitive impairment is one of the factors that contribute to the suffering of patients with MDD. Therefore, this study investigated the characteristics and differences in cognitive functioning of AD and non-atypical depression (non-AD) using the MATRICS Consensus Cognitive Battery (MCCB).

METHODS

A total of 101 patients with AD and 252 patients with non-AD were assessed with the MCCB and clinical scales. Propensity score matching (PSM) was used to balance confounders between groups. After PSM, between-group differences were compared for cognitive and clinical variables. In addition, multiple linear regression analyses were performed to explore the effects of cognitive and clinical variables on the quality of life.

RESULTS

The AD group scored significantly lower in attention/vigilance and social cognition in all cognitive domains than the non-AD group. Attention/vigilance and social cognition were significant positive predictors of quality of life, whereas atypical symptoms and depressive severity were significant negative predictors.

CONCLUSIONS

This study suggests significant differences in cognitive functions between the AD and non-AD subtypes. Atypical symptoms and impaired cognition have a negative impact on patients' quality of life. Attention/vigilance and social cognition are worse in AD than non-AD, which the atypical features of patients with AD may explain. The pathological mechanisms and treatment strategies of AD should be further explored in the future to promote individualized treatment strategies.

Cognitive Function and Depressive Symptoms among Chinese Adults Aged 40 Years and Above: The Mediating Roles of IADL Disability and Life Satisfaction

The purpose of this study was to investigate the relationship between cognitive function and depressive symptoms among Chinese adults aged 40 years and above, as well as the series of multiple mediating effects of Instrument Activities of Daily Living disability and life satisfaction on this relationship. The data was obtained from the China Health and Retirement Longitudinal Study (CHARLS, 2013-2018), including 6466 adults aged 40 years and above. The mean age of the adults was 57.7 ± 8.5. The SPSS PROCESS macro program was conducted to examine the mediating effects. The results indicated that there was a significant association between cognitive function and depressive symptoms five years later (B = -0.1500, 95%CI: -0.1839, -0.1161), which could also be demonstrated through three mediation pathways: (1) the mediating pathway through IADL disability (B = -0.0247, 95%CI: -0.0332, -0.0171); (2) the mediating pathway through life satisfaction (B = 0.0046, 95%CI: 0.0000, 0.0094); and (3) the chain mediation pathway through IADL disability and life satisfaction (B = -0.0012, 95%CI: -0.0020, -0.0003). Both IADL disability and life satisfaction have been proven to be crucial mediators for the relationship between cognitive function and depressive symptoms five years later. It is necessary to improve individuals' cognitive function and reduce the negative impact of disability on them, which is important to enhance their life satisfaction and prevent depressive symptoms.

Discrepancy between self- and observer-rated depression severities as a predictor of vulnerability to suicide in patients with mild depression

BACKGROUND

Discrepancies in depression severity between the Hamilton Depression Rating Scale (HAMD) and the Beck Depression Inventory (BDI) have been reported. However, whether these discrepancies impact vulnerability to suicide in patients with major depressive disorder (MDD) remains unclear.

METHODS

Patients with mild MDD (n=161) were enrolled in the study and divided into the following 3 groups: (1) patients with MDD with the discrepancy (n=45), i.e., those with low HAMD17 scores (8-13) and high BDI-II scores (≥29), (2) patients with MDD without the discrepancy (n=46), i.e., those with low HAMD17 scores and low BDI-II scores (≤28), and (3) patients not currently depressed (n=70), i.e., those with HAMD17 scores ≤7 (affective controls). We examined the relationship of demographic, clinical, and neuropsychological variables with any discrepancy between self-rating and observer rating.

RESULTS

Patients with MDD with the discrepancy had significantly higher hopelessness than those without the discrepancy and affective controls. Verbal fluency task performance of patients with MDD with the discrepancy was significantly impaired compared with that of those without the discrepancy and affective controls. Stepwise logistic regression analysis revealed that a history of suicide attempt [odds ratio (OR), 3.57; 95% confidence interval (CI), 1.12-11.37] and hopelessness (OR, 1.23; 95% CI, 1.09-1.38) increased odds of the discrepancy.

LIMITATIONS

Results require replication.

CONCLUSIONS

Clinicians should examine discrepancies between self- and observer-rated depression severities, which are associated with vulnerability to suicide in patients with MDD, even if objectively evaluated as mild.

Psychomotor retardation in elderly untreated depressed patients

BACKGROUND

Psychomotor retardation (PR) is one of the core features in depression according to DSM V (1), but also aging in itself causes cognitive and psychomotor slowing. This is the first study investigating PR in relation to cognitive functioning and to the concomitant effect of depression and aging in a geriatric population ruling out contending effects of psychotropic medication.

METHODS

A group of 28 non-demented depressed elderly is compared to a matched control group of 20 healthy elderly. All participants underwent a test battery containing clinical depression measures, cognitive measures of processing speed, executive function and memory, clinical ratings of PR, and objective computerized fine motor skill-tests. Statistical analysis consisted of a General Linear Method multivariate analysis of variance to compare the clinical, cognitive, and psychomotor outcomes of the two groups.

RESULTS

Patients performed worse on all clinical, cognitive, and PR measures. Both groups showed an effect of cognitive load on fine motor function but the influence was significantly larger for patients than for healthy elderly except for the initiation time.

LIMITATIONS

Due to the restrictive inclusion criteria, only a relatively limited sample size could be obtained.

CONCLUSION

With a medication free sample, an additive effect of depression and aging on cognition and PR in geriatric patients was found. As this effect was independent of demand of effort (by varying the cognitive load), it was apparently not a motivational slowing effect of depression.

A multifaceted prospective memory intervention to improve medication adherence: design of a randomized control trial

Adherence to prescribed antihypertensive agents is critical because control of elevated blood pressure is the single most important way to prevent stroke and other end organ damage. Unfortunately, nonadherence remains a significant problem. Previous interventions designed to improve adherence have demonstrated only small benefits of strategies that target single facets such as understanding medication directions. The intervention described here is informed by prospective memory theory and performance of older adults in laboratory-based paradigms and uses a comprehensive, multifaceted approach to improve adherence. It incorporates multiple strategies designed to support key components of prospective remembering involved in taking medication. The intervention is delivered by nurses in the home with an education control group for comparison. Differences between groups in overall adherence following the intervention and 6 months later will be tested. Systolic and diastolic blood pressure levels also will be examined between groups and as they relate to adherence. Intra-individual regression is planned to examine change in adherence over time and its predictors. Finally, we will examine the association between executive function/working memory and adherence, predicting that adherence will be related to executive/working memory in the control group but not in the intervention group.

Sustained cognitive impairments after clinical recovery of severe depression

Neuropsychological impairment is prominent in patients with depression, but it is unclear whether deficits persist after clinical response. This study aimed to investigate neuropsychological functions in the course of the illness. Depressive patients were investigated in the acute state and after clinical response using an extensive neuropsychological test battery. After clinical response, there was only a partial improvement in learning and memory and there were no changes regarding working memory, executive functions, and attention. Transient impairments in visual learning and memory suggest a depression-related state effect. The continuing deficits in attention, working memory, and executive function might be considered a trait marker.

Frontal and right temporal activations correlate negatively with depression severity during verbal fluency task: a multi-channel near-infrared spectroscopy study

Multi-channel near-infrared spectroscopy (NIRS) is a noninvasive, on-the-spot, functional neuroimaging technique allowing detection of the spatiotemporal characteristics of brain activity. Previous NIRS studies indicated the oxy-hemoglobin (oxy-Hb) increase during a verbal fluency task (VFT) is attenuated in patients with major depressive disorder (MDD) as compared with healthy controls. However, the possible relationship between depression symptom severity and oxy-Hb change on NIRS has not yet been elucidated. To examine this relationship, we recruited 30 patients with MDD and 30 age-, gender- and intelligence quotient-matched controls. All underwent NIRS during VFT. As expected, the oxy-Hb increase during the task was significantly smaller in patients than in controls. After false discovery rate correction using 31 channels, the mean increase in oxy-Hb during the task showed a significant negative correlation with the total score of the Hamilton Rating Scale for Depression 21-item version (ch25: rho = -.56; FDR-corrected p: .001). When each item of the HAM-D21 was examined individually, insomnia early in 9 channels (rho = -.63 to -.46; FDR corrected p: .000-.014), work and activity in 2 channels (rho = -.61 to -.57; FDR corrected p: .001 to .003) and psychomotor retardation in 12 channels (rho = -.70 to -.44; FDR corrected p: .000-.018) showed significant negative correlations with the mean oxy-Hb increase in the right frontal temporal region. Although it is possible that our results were affected by medication, these data suggest reduced right frontal temporal activation on NIRS during VFT is related to the symptom severity of MDD.

Response time variability and response inhibition predict affective problems in adolescent girls, not in boys: the TRAILS study

The present study examines the relationship between neurocognitive functioning and affective problems through adolescence, in a cross-sectional and longitudinal perspective. Baseline response speed, response speed variability, response inhibition, attentional flexibility and working memory were assessed in a cohort of 2,179 adolescents (age 10-12 years) from the TRacking Adolescents' Individual Lives Survey (TRAILS). Affective problems were measured with the DSM-oriented Affective Problems scale of the Youth Self Report at wave 1 (baseline assessment), wave 2 (after 2.5 years) and wave 3 (after 5 years). Cross-sectionally, baseline response speed, response time variability, response inhibition and working memory were associated with baseline affective problems in girls, but not in boys. Longitudinally, enhanced response time variability predicted affective problems after 2.5 and 5 years in girls, but not in boys. Decreased response inhibition predicted affective problems after 5 years follow-up in girls, and again not in boys. The results are discussed in light of recent insights in gender differences in adolescence and state-trait issues in depression.

At-fault motor vehicle crash risk in elderly patients treated with antidepressants

OBJECTIVE

To assess whether antidepressant treatment is associated with a temporary increase in the risk of a motor vehicle crash among older adults.

DESIGN

Population-based case-only time-to-event analysis.

SETTING AND SUBJECTS

Data from transportation and healthcare databases for adults age 65 and older in Ontario, Canada, between January 1, 2000, and October 31, 2007. Consecutive adults who had a motor vehicle crash anytime following their 66th birthday.

MEASUREMENTS

The primary exposure variable was treatment with antidepressant medication, and the primary outcome measure was a motor vehicle crash.

RESULTS

A total of 159,678 individuals had a crash during the study, of whom 7,393 (5%) received an antidepressant in the month prior to the crash. The hazard ratio (HR) of crash associated with second-generation antidepressants was 1.10 (95% confidence interval [CI]: 1.07-1.13, χ² = 41.77, df = 1, p <0.0001), adjusted for gender, license suspensions, and other medications, but the risk for first-generation antidepressants was not significant. The increased risk was restricted to those who were also concurrently prescribed a benzodiazepine (adjusted HR: 1.23, 95% CI: 1.17-1.28, χ² = 85.28, df = 1, p <0.0001) or a strong anticholinergic medication (adjusted HR: 1.63, 95% CI: 1.57-1.69, χ² = 627.31, df = 1, p <0.0001), and was confined to crashes where the patient was at fault. The increased risk was apparent for the first 3-4 months following initiation of an antidepressant and returned to baseline thereafter.

CONCLUSIONS

Prescriptions for second-generation antidepressants in older adults are associated with a modest increased risk of motor vehicle crashes, when combined with other medications that can impair cognition.

Identifying a cognitive impairment subgroup in adults with mood disorders

BACKGROUND

We hypothesized that only a minority of patients with mood disorders have measurable cognitive impairment, and this minority drives the small-to-medium effect sizes detected in group studies. Removal of this minority from group statistical analyses will illustrate that the majority appear to have broadly normal cognitive functioning.

METHODS

Participants were adults between the ages of 20 and 54, including 659 healthy control subjects, 84 unmedicated outpatients diagnosed with depression, 59 outpatients diagnosed with depression who were on medications at the time of the evaluation, and 43 outpatients with bipolar disorder. All completed the CNS Vital Signs computerized cognitive screening battery.

RESULTS

The prevalence rates of low cognitive test scores were calculated for the healthy control subjects and the patients with mood disorders. Having two scores at or below the 5th percentile occurred in 31.2% of the patients and only 8.2% of the control subjects [χ(2)(1)=66.67, p<.0001; Odds Ratio=5.1, 95% CI=3.4-7.7]. For the control subjects, this low false positive rate for cognitive impairment was maintained across age groups, sexes, and education levels. A larger proportion of patients with bipolar disorder (41.9%) than patients with depression (27.1-28.6%) met this criterion for cognitive impairment.

CONCLUSIONS

This study suggests that cognitive impairment associated with mood disorders is limited to a minority of patients with the majority being broadly cognitively normal. Future research should determine if this identified subgroup has neuroanatomical, neurophysiological, or neuroendocrine abnormalities. Cognitive screening tools of this type might be useful in selecting participants for studies.

Neuropsychologische Aspekte der Depression

Zusammenfassung. Patienten mit Depressionen klagen häufig über Symptome und Störungen nicht nur auf der emotionalen, sondern auch auf der kognitiven Ebene. In dieser Übersichtsarbeit werden schwerpunktmäßig neuropsychologische Befunde zu kognitiven Funktionen bei unipolaren Depressionen zusammengefasst. Die kognitive Theorie der Depression postulierte eine Beeinflussung kognitiver Vorgänge durch emotionale Verzerrungen, die eine wichtige Rolle bei Vulnerabilität, Entstehung, Aufrechterhaltung und Rezidiven depressiver Episoden spielen. Befunde zu dieser Interaktion von kognitiven und emotionalen Prozessen werden dargestellt, außerdem wird auf die Bedeutung dieser Aspekte für die Emotionsregulation und für die Therapie der Depression eingegangen.

Hippocampal visuospatial function and volume in remitted depressed patients: an 8-year follow-up study

BACKGROUND

Several lines of evidence suggest hippocampal dysfunction in major depression, but the prevalence and nature of specific dysfunctions during the long-term course of major depression is yet to be assessed. A 3D virtual environment navigation task and measurements of hippocampal volume were assessed in remitted former inpatients with moderate to severe depression after an 8 year follow-up period to evaluate whether functional and structural differences existed in the hippocampus beyond depression.

METHODS

Performance on a right hippocampus-dependent 3D virtual reality navigation task, memory tests and right and left hippocampal volumes were assessed in 31 remitted depressed (unipolar) patients and 37 healthy subjects.

RESULTS

Remitted depressed patients did not differ significantly from healthy subjects in terms of either neuropsychological performance or hippocampal volume.

LIMITATIONS

The sample consisted of remitted inpatients that had been treated with psychotropic drugs during the 8-year follow-up period. Moreover, 11 of the 42 patients included in the original study were excluded from the follow-up study due to persisting depressive illness and suicide.

CONCLUSIONS

The study of visuospatial navigation ability and hippocampal volume in remitted depressed patients offers a specific way of assessing dysfunction in the hippocampus in major depression. Our findings do not support the notion that hippocampal impairment of visuospatial function exists beyond the depressive state, thus indicating that hippocampus-related cognitive dysfunction and previously reported reduced hippocampal volume might represent a state and not a permanent trait of the illness. Moreover, our study suggests that intensive drug treatment of the depressive episodes might prevent the deterioration of the hippocampus.

Identifying neurocognitive impairment in depression using computerized testing

There is considerable interest in the identification of neurocognitive impairment in patients with depression. The purpose of this study is to illustrate a methodology for identifying frank neurocognitive impairment in clinical practice and research using a computerized battery of neuropsychological tests. Participants were 100 adult patients with depression who were not on antidepressants. They were carefully matched on age, education, gender, and ethnicity to 100 healthy adult control subjects. All participants completed the Central Nervous System Vital Signs (CNS-VS) computerized assessment battery, which takes approximately 30-40 minutes to administer. Patients with depression performed more poorly than controls on all five domain scores (Cohen's d ranged from d = .37 to .72). When using two or more scores below the 5th percentile as the cutoff for frank neurocognitive impairment, 31.0% of the depressed sample and only 5.0% of the control sample scored in this range. In this study, patients with depression were 8.5 times more likely to have two or more index scores that were below the 5th percentile. Computerized testing, using the interpretive methodology presented, represents an efficient methodology for identifying cognitive problems in patients who present with untreated depression.

Stroop performance in major depression: selective attention impairment or psychomotor slowness?

BACKGROUND

Numerous neuropsychological studies reported impaired Stroop performance in major depressive disorder (MDD) patients.

METHODS

The present study attempted to identify possible neuropsychological mechanisms involved in this impairment in untreated MDD outpatients (n=75) as compared to healthy subjects (n=83). Inspection Time, Finger Tapping, Simple and Choice Reaction Time were considered as measures of perceptual, motor, psychomotor speed, and response selection, respectively.

RESULTS

MDD patients performed significantly slower than healthy controls in the neutral and the congruent conditions, but not in the incongruent ones. In order to identify predictors of Stroop performance, linear hierarchical regressions analyses were performed. Age, motor and psychomotor speed were predictors of response time and accuracy on Stroop performance. Significant correlations between response time and the number of errors in all three Stroop conditions were found in MDD patients, while such a correlation was obtained in the healthy controls only in the incongruent condition.

LIMITATIONS

Although education was included as a covariate in our analyses, suggesting that the observed effects could not be ascribed to education differences, further testing with education-matched samples is warranted.

CONCLUSIONS

Our study shows that the Stroop task performance is affected by both aging and MDD. Impairment in the Stroop performance can be predicted by psychomotor slowness and by vigilance level in MDD outpatients, but not by impairment of selective attention per se.

The added burden of comorbidity in patients with asthma

OBJECTIVE

Compare the prevalence of comorbidities in adults with and without asthma in Canada and investigate the association between comorbidities in patients with asthma and the occurrence of asthma symptoms or attacks.

METHODS

Survey data from the 2005 Canadian Community Health Survey (CCHS) were analyzed. A total of 132,221 Canadians participated in the national survey; 10,089 adult respondents from 10 Canadian provinces and 3 territories reported having asthma. Analyses focused on 11 major chronic comorbidities.

RESULTS

Respondents with asthma were more likely to have comorbidities except cancer; 31% of respondents with asthma and comorbidities reported their health status to be fair or poor. For respondents with asthma, non-asthma chronic respiratory disease, mental illness, and allergy were significantly associated with having asthma symptoms or attacks.

CONCLUSIONS

Many Canadians with asthma report a high comorbidity burden. These patients will likely require more health services and more complex health management strategies. Comorbid conditions should be clearly identified with particular emphasis on management of mood disorders and anxiety because these conditions are likely to increase asthma symptomatology and may be unrecognized by clinicians.

Residual Cognitive Deficit in Adults with Depression who Recovered after 6-month Treatment: Stable versus State-Dependent Markers

BACKGROUND

Knowledge of depression-related disturbances in cognitive functioning is advancing, but little is known about the cognitive response to treatment for major depression, especially in younger adults. This study investigated the deficits in multiple cognitive domains in middle-aged patients with major depressive disorder (MDD), using a prospective follow-up study design.

METHODS

The sample consisted of 13 medication-free MDD patients and 13 education- and age-matched healthy controls. All subjects were administered clinical measures as well as a comprehensive neurocognitive test battery aimed at assessing multiple cognitive domains at the time of recruitment. Patients remitted after 6 months following treatment repeated the neurocognitive assessment.

RESULTS

There were significant differences between the depressed subjects and controls at baseline. MDD patients with remitted symptoms still showed significant deficits in executive function and motor function, but not in memory or attention domains. Patients had significant improvement in memory and attention domains only, once their depressive symptoms had subsided; while executive functioning as well as motor functioning remained unchanged.

CONCLUSIONS

Executive functioning and motor functioning deficits might be stable vulnerability indicators for MDD, and memory and attention impairment might serve as state-dependent indicators for MDD.

KEYWORDS

Major depressive disorder; Remission; Residual; Cognitive deficits; Follow-up.

A comparison of neurocognitive impairment in younger and older adults with major depression

BACKGROUND

Neurocognitive impairment is a well-recognized feature of depression that has been reported in younger and older adults. Similar deficits occur with ageing and it is unclear whether the greater deficits in late-life depression are an ageing-related phenomenon or due to a difference in the nature of late-life depression itself. We hypothesized that ageing alone would not fully explain the increased neurocognitive impairment in late-life depression but that differences in the illness explain the greater decrements in memory and executive function.

METHOD

Comparison of the neuropsychological performance of younger (<60 years) and older (60 years) adults with major depressive disorder (MDD) and healthy comparison subjects. Scores for each depression group were normalized against their respective age-matched control group and the primary comparisons were on four neurocognitive domains: (i) attention and executive function; (ii) verbal learning and memory; (iii) visuospatial learning and memory; and (iv) motor speed.

RESULTS

We recruited 75 subjects with MDD [<60 years (n=44), 60 years (n=31)] and 82 psychiatrically healthy comparison subjects [<60 years (n=42), 60 years (n=40)]. The late-life depression group had greater impairment in verbal learning and memory and motor speed but not in executive function. The two depressed groups did not differ in depression severity, global cognitive function, intelligence or education.

CONCLUSIONS

Late-life depression is associated with more severe impairment in verbal learning and memory and motor speed than depression in earlier adult life and this is not due to ageing alone.

Changes in everyday and semantic memory function after electroconvulsive therapy for unipolar depression

OBJECTIVES

This long-term prospective study focuses on the effects of electroconvulsive therapy (ECT) on everyday memory function and on semantic memory function.

METHODS

Results of memory test from 96 consecutive inpatients treated for unipolar depression were analyzed prospectively before ECT, after ECT treatment, and at 3- and 12-month follow-up. Everyday memory function was assessed by means of the Rivermead Behavioural Memory Test (RBMT) and semantic memory by 2 forms of the word fluency test.

RESULTS

In our study, age had a constant and significant negative effect on everyday memory (RBMT score) over time. Bilateral electrode placement mainly influenced everyday memory, which was significantly improved at 3-month follow-up. One year after discharge, the RBMT scores were not significantly different from pretreatment levels, indicating that ECT does not affect everyday memory on the longer term. Scores on both word fluency tests for semantic memory were significantly influenced by age over time. The effect of age changed from a negative influence directly after ECT to a positive effect at follow-up. This advantage of higher age indicates that the semantic memory of older patients receiving ECT for severe mood disorder shows greater improvement at follow-up compared with younger patients. Over time, the scores on only 1 of the word fluency tests were significantly influenced by mainly bilateral electrode placement.

CONCLUSIONS

A small but reversible decrease in everyday memory occurs after ECT in depressed patients, which is influenced by age and electrode placement. Semantic memory shows a fluctuating but recovering course, which is also influenced by age and electrode placement. During follow-up, the improvement in semantic memory was greater in the older patients.

A study of the neural correlates of episodic memory and HPA axis status in drug-free depressed patients and healthy controls

Altered laterality of cortical activity, neuropsychological impairment and hypercortisolaemia have been shown in depression. The neural correlates of episodic memory in healthy subjects demonstrate hemispheric laterality but it is not known whether this is affected by depression and/or hypercortisolaemia. Twenty-seven drug-free depressed patients and 29 matched healthy controls were studied. Event-related potentials (ERPs) were recorded during an episodic memory test. During the study phase, subjects heard words spoken in either a male or female voice. Old and new words were presented visually during a test phase, when subjects were requested to identify words as old or new and recollect the gender of the voice for old words. Cortisol levels were measured in saliva and plasma samples. The results showed a trend for elevated salivary cortisol concentration in depressed patients. Reaction times were significantly longer in patients; however, there was no difference in memory accuracy performance between the two groups. Recollection performance was found to be negatively correlated with age, with a similar trend for cortisol concentrations. ERP activity not specifically related to episodic memory retrieval recorded 200-500ms post-stimulus from controls showed a marked laterality, with higher voltages over the right hemisphere; however, was not seen in patients. There was significant correlation between cortisol and the laterality of the neural activity specifically related to episodic memory retrieval recorded 500-1400ms post-stimulus in both depressed and healthy groups. These unique findings demonstrate that while the laterality of the neural correlates of episodic memory is sensitive to cortisol, it is not altered by the non-specific laterality effects seen in depression.

A longitudinal analysis of neurocognitive function in unipolar depression

Neurocognitive function is reduced in major depression, but uncertainties remain about if and to what extent improvement in neurocognitive function follows remission of depressive symptoms. A total of 30 patients with Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition (DSM-IV) diagnosis of unipolar major depressive disorder (MDD) at baseline were tested neuropsychologically again, after a mean test-retest interval of 2 years. At retest, patients were partly or completely recovered from depression. Remission of depression was followed by improvement in verbal memory function up to the level of healthy controls, but no associations between improvement in depression and improvement in other dimensions of neurocognitive function were found. Neurocognitive function at baseline was not predictive of improvement in depressive symptoms over time. The present study provided some support for the state hypothesis as to the association between neurocognitive impairment and depression.

Neuropsychological impairment in major depression: its nature, origin and clinical significance

Neuropsychological impairment is well established as a feature of major depressive disorder (MDD) but studies have shown a variable pattern of impairment. This paper seeks first to clarify this by examining methodological and clinical factors that give rise to variability in study findings. Second, it examines theories of the origin of these neuropsychological abnormalities. Third, it reviews evidence regarding the clinical significance of different patterns of deficit. A selective review was undertaken of the literature with a particular emphasis on methodological factors, the influence of clinical subtypes and prevalent theories of neuropsychological abnormality. Methodological issues and the heterogeneity of MDD account for considerable variability in results. Specific investigation of the subtypes of psychotic MDD, melancholic MDD and bipolar depression reduces this heterogeneity and results are more consistent in the elderly. Hypothalamic-pituitary-adrenal axis dysfunction is associated with neuropsychological dysfunction in MDD although evidence of direct causation is not definitive at present. Impairment of executive and psychomotor function is a consistent finding, particularly in the elderly, and may reflect frontostriatal-limbic dysfunction. There is growing evidence that this may have clinical significance. It is suggested that future research take very careful account of the exact phenotype of MDD. Classification based on neuropsychological profile may, in fact, be useful. Further research should examine further the clinical importance of patterns of neuropsychological impairment.

Incident major depression does not affect neuropsychological functioning in HIV-infected men

The diagnosis of lifetime major depressive disorders (MDDs) and of current major depressive episodes (MDEs) are relatively common in HIV-infected individuals, and often are assumed to influence neuropsychological (NP) performance. Although cross-sectional studies of HIV-infected individuals generally have found no systematic link between current MDE or depressive symptoms and NP performance, longitudinal studies are needed to clarify whether incident MDE may impact NP functioning in at least some cases. Two hundred twenty-seven human immunodeficiency virus (HIV)-infected adult men, who did not meet criteria for a current MDE at baseline, participated in a longitudinal NP study for an average of two years. Participants received repeated NP assessments, as well as structured psychiatric interviews to ascertain presence or absence of both lifetime MDD and current MDE. Ninety-eight participants had a lifetime history of MDD, and 23 participants met criteria for incident MDE at one of their follow-up evaluations. Groups with and without lifetime MDD and/or incident MDE had comparable demographics, HIV disease status and treatment histories at baseline, and numbers of intervening assessments between baseline and the final follow-up. Lifetime MDD was associated with greater complaints of cognitive difficulties in everyday life, and such complaints were increased at the times of incident MDE. However, detailed group comparisons revealed no NP performance differences in association with either lifetime or incident major depression. Finally, NP data from consistently nondepressed participants were used to develop "norms for change" and these findings failed to show any increased rates of NP worsening among individuals with incident MDE. Our results suggest that neurocognitive impairment and major depression should be considered as two independent processes.

The association between depressive mood and cognitive performance in an elderly general population - the MEMO Study

The aim of this study was to analyse the influence of the severity of depressive symptoms on different domains of cognitive function in the elderly. In a population-based cross-sectional study, 385 participants aged 65-83 years were interviewed with the Center for Epidemiologic Studies Depression Scale (CES-D) and performed a standardized neuropsychological test assessing attention, memory, cognitive speed and motor function. Multivariate linear regression analyses revealed a significant effect of depressive symptoms on a single test (Stroop test 1) and two summary scores (memory and motor function). After full adjustment for education and Mini Mental State Examination, the memory score was partly attenuated. Stratified analysis showed that an increase in CES-D scores led to a larger decline of cognitive test results in participants with mild to moderate depressive symptoms, compared to those with a high degree of depressive symptoms. Our results suggest that depressive mood in older adults is primarily associated with decreased processing speed and motor functioning, but not executive control functions. According to our results depressive mood is not necessarily associated with memory deficits in older adults. Changes in depressive symptoms in milder forms of depressive mood are associated with a larger decline in cognitive function than in severer forms of depressive mood.

Psychological factors and quality of life in arthritis: a population-based study

Previous studies using clinic or convenience samples have indicated that not only patients with arthritis are at increased risk of depression, but there may also be a link between depression and disability in people with arthritis. We examined the prevalence of psychological distress in a population sample with and without arthritis and the association with health-related quality of life. The WANTS Health and Well-being Survey was a population household telephone interview survey of adults (age > or =18 years) in three states of Australia. Data obtained were weighted to provide population-representative estimates. The survey included questions regarding arthritis, SF-12, the Kessler 10 index of psychological distress and presence of mental health conditions. A total of 7,473 interviews providing information on arthritis were completed, with 1,364 (18.3%) reporting arthritis. Self-reported mental health conditions were more frequent in those with arthritis (14.9 vs 12.0%, p = 0.004), and a higher proportion were at a medium or high risk for anxiety or depression (39.0 vs 31.0%, p < 0.001). People with arthritis had significantly lower scores on the SF-12 physical component summaries compared to those without arthritis. Among those with arthritis, those with coexisting psychological distress had significantly lower scores on the SF-12 physical component summary than those without psychological distress. Psychological distress is common among people with arthritis in the community. In arthritis, psychological distress makes a significant additional negative impact on the physical well-being. Physicians need to recognize and address this additional impact on physical functioning in patients with arthritis.

Chemotherapy and Cognition: Effects, Potential Mechanisms, and Management

The development of novel chemotherapeutic agents and advances in treatment technique have improved survival for patients diagnosed with some forms of cancer, but treatments are not always site specific and may place normal tissues at risk. The central nervous system (CNS) is susceptible to treatment effects and complaints of memory loss and generalized cognitive decline are common among cancer patients. Despite the frequency of subjective patient complaints, studies evaluating the cognitive abilities of patients have inconsistently reported chemotherapy-related declines. On careful review of the literature, discrepant findings across studies (some documenting chemotherapy-related cognitive declines and others failing to detect such changes) may be attributed to differences in methodology. Most studies have been retrospective in design, omit pretreatment assessment of function, use small or heterogeneous samples, use inappropriate measures to assess cognition, and fail to incorporate control subjects. Though rare to date, prospective, randomized, longitudinal studies that incorporate pretreatment comprehensive neuropsychological assessment are necessary to define the severity and pattern of treatment-related change. Building on a foundation of solid science, future studies may identify subgroups of patients susceptible to significant chemotherapy-related cognitive decline. Once these groups are identified and the mechanisms underlying the decline are elucidated, attention may be turned to the development of treatments that may optimize cognitive function and improve patient quality of life.

Age effects in time estimation: relationship to frontal brain morphometry

Compared with many other cognitive functions, relatively little is known about time representation in the brain. Recent work shows disrupted timing and time estimation in older adults, although it is unclear whether these effects are the result of normal aging or disease-related processes. The present study examined time estimation in persons across the adult lifespan who were free from significant medical or psychiatric history. Results showed older adults exhibited greater variability in time estimation, but no evidence for systematic acceleration or slowing emerged. This variability was correlated with performance on a variety of cognitive tests including attention, working memory and executive function. Although no relationship emerged between time estimation and EEG indices from central regions, multiple MRI indices were significantly correlated with time estimation. Stepwise regression showed volume of the supplementary motor area predicted variability in time estimation. These results indicate that healthy aging is associated with altered time estimation and suggest that changes in frontal brain regions mediate these effects.

Patterns of cognitive performance in middle-aged and older adults: A cluster analytic examination

Cognitive decline in speeded abilities, executive function, and memory is believed to typify normal aging. However, there is significant variability in cognitive function with advanced age and some reports of relatively intact cognitive function among a subset of older individuals. The present study consists of a cluster analysis to examine the patterns of cognitive function in middle-aged and older individuals. Analyses revealed 3 clusters of middle-aged adults, including an intact group, persons with poor motor speed, and a group with reduced executive function. Three clusters were also identified for older adults, including a group with poor executive function, persons with reduced speed performance (attention, executive function, motor), and a group with global cognitive decline. No evidence emerged for a cluster of older adults with intact performance in all domains or with isolated memory deficits. Findings generally support the frontal aging hypothesis and may provide important information about healthy cognitive aging.

Pharmacological approaches to the treatment of residual symptoms

Despite the efficacy of currently available antidepressant treatment, residual symptoms are common among individuals treated for major depressive disorder and are associated with an increased risk of relapse and poor psychosocial functioning. However, distinguishing treatment-emergent side effects from residual symptoms can be challenging for clinicians. Anxiety, sleep disturbance, somnolence/fatigue, apathy and cognitive dysfunction are among the more frequent residual symptoms. Approaches to the management of residual symptoms include addressing treatment-emergent side effects and co-morbid conditions, optimizing antidepressant dosing and using augmentation therapy. Clinicians are often guided in their decisions by anecdotal impressions. Studies assessing the evaluation and treatment of residual symptoms and side effects will contribute importantly to the optimal acute and long-term management of depression.

Side-effects of chemotherapy and quality of life in ovarian and breast cancer patients

PURPOSE OF REVIEW

Women diagnosed with ovarian cancer or breast cancer often face aggressive chemotherapy involving multiple treatment regimens. These treatments may be associated with significant side-effects that adversely impact patient quality of life. In this review, we will highlight recent research on side-effects of chemotherapy and the quality-of-life concerns of women with ovarian and breast cancer.

RECENT FINDINGS

Adjuvant chemotherapy has demonstrated efficacy in the management of ovarian and breast cancers. In addition to physical side-effects, a subset of women receiving chemotherapy will experience significant cognitive dysfunction that adversely affects their perceived quality of life. Variables including disease response, treatment indication and extent of the patient's social support also influence quality-of-life ratings.

SUMMARY

Although prolongation of survival remains the primary goal of chemotherapy, the palliation of symptoms and preservation of quality of life are also important treatment considerations. Chemotherapy may be associated with nausea, vomiting, hair loss, cognitive dysfunction, fatigue, changes in sexual functioning and reductions in quality-of-life ratings. Although rare to date, prospective, randomized, longitudinal studies that incorporate a pre-treatment assessment of symptom burden and perceived quality of life are necessary to define the severity and pattern of treatment-related change and subsequently guide intervention strategies. In some cases, quality-of-life issues may help to guide patient-care decisions.

Cognitive and Demographic Determinants of Dementia in Depressed Patients with Subjective Memory Complaints

BACKGROUND

Previous studies showed that late-life depression with subjective memory complaints (SMC) may be associated with an increased risk of developing dementia. However, not all such patients have cognitive decline. The aim of this longitudinal study was to identify possible clinical determinants of progressive deterioration in depressed elderly patients with SMC.

METHOD

Forty-one consecutive patients referred to a memory clinic because of persistent SMC were investigated and received an ICD-10 diagnosis of mild to moderate depression. Over a mean follow-up period of 15 months, 9 of them (22%) developed dementia. Statistical analysis included Mann-Whitney U and Fisher's exact tests as well as univariate and multivariate logistic regression analyses to assess the relationship between cognitive decline and clinical, demographical and neuropsychological characteristics at baseline.

RESULTS

Age at baseline was associated with subsequent dementia, and performance on immediate verbal prose recall and a visual organization test at the initial assessment were worse in those who showed cognitive decline. In a multivariate model, age and immediate recall predicted 32.7% of the cognitive variability, with an additional 2.4% when a visual organization test was added. There was no correlation between cognitive performance and severity of depression at baseline. The study was limited by a small sample size, the nondistinction of depressive subtypes and the absence of a formal neuropsychological assessment on follow-up.

CONCLUSION

Impairment of the executive component of working memory as well as limited access to visual knowledge may predict cognitive deterioration in depressed patients with subjective memory complaints.

The association between depression, anxiety, and cognitive function in the elderly general population--the Hordaland Health Study

OBJECTIVES

To examine the association between depression and/or anxiety and cognitive function in the elderly general population.

SUBJECTS

Non-demented participants from the general population (n = 1,930) aged 72-74 years.

METHODS

Symptoms and caseness of depression and anxiety disorder were assessed using the Hospital Anxiety and Depression Scale (HADS). Cognitive function was assessed by the Digit Symbol Test (modified version), the Kendrick Object Learning Test, and the 'S'-task from the Controlled Oral Word Association Test.

RESULTS

There was a significant association between depression and reduced cognitive function. The inverse association between anxiety and reduced cognitive performance was explained by adjustment for co-morbid depression. The inverse association between depressive symptoms and cognitive function was found to be close to linear, and was also present in the sub-clinical symptom range. Males were more affected cognitively by depressive symptoms than females.

CONCLUSION

The inverse association between depression and cognitive function is not only a finding restricted to severely ill patient samples, but it can also be found in the elderly general population.

Asthma and depression: a pragmatic review of the literature and recommendations for future research

BACKGROUND

Although the association between asthma and psychosocial factors has long been recognised, it is only in the last decade that the impact of coexisting asthma and depression has become the focus of considerable research interest. However, the findings so far have been confusing and often contradictory. This paper sets out a methodical review and appraisal of the literature to date, including suggestions for future research.

METHOD

PubMed and PsycINFO databases were used to search for English-language articles relating to asthma and depression research. The resulting articles were then reviewed and summarised, creating a report that was used to develop research recommendations.

RESULTS

The main findings from this review included: (a) results are mixed as to whether persons with asthma are more likely to be depressed than those without asthma; (b) asthma and depression may have an 'additive' adverse effect on the normal asthma-related quality of life reductions; (c) subjective measures of asthma severity may be more strongly related to depression than objective measures; (d) specific asthma symptoms appear to be linked to depression; (e) sadness and depression can produce respiratory effects consistent with asthma exacerbations; (f) depression appears to be negatively related to asthma treatment compliance; (g) corticosteroid use in asthma treatment has been associated with depression, though it is unclear how common this problem is in real life; (h) interventions that address the physical, psychological, and social consequences of asthma are likely to lead to the most successful treatment outcomes; (i) treating the depression of individuals with asthma is likely to minimise the negative effects of the coexistence; and (j) a number of common methodological problems were observed in the literature.

RECOMMENDATIONS

There is a large amount of research yet to be undertaken to clarify issues around asthma and depression, with the overdue next step being to design integrated treatment approaches, and carry out large-scale prospective studies to determine the impact of using such approaches to treat individuals with depression and asthma. Such studies will be the only way in which some fundamental questions about the development and coexistence of these two conditions will be answered.

Impulsivity in depressed children and adolescents: a comparison between behavioral and neuropsychological data

Impulsivity at the neuropsychological and behavioral levels was investigated in a sample of drug-naive depressed children and adolescents. The performance of 21 patients with a current diagnosis of mood disorder was compared with that of 21 normal controls on tests of executive functions related to impulsivity (Matching Familiar Figures Test, Continuous Performance Test, Verbal Fluency, Stroop Test, and Walk-Don't Walk) and on impulsive/restless behavior on the Conners' Parent Rating Scale. Depressed children and adolescents showed a pattern of conservative response style, with slow reaction times and attentional problems, similar to that observed in adults, and a general delay/difficulty in response initiation on the Fluency Test. Depressed participants were rated by their parents as being significantly more impulsive/restless than controls. However, there was no evidence of an impulsive cognitive response style in more impulsive/restless patients. Symptom severity (Hamilton Rating Scale for Depression) and subjective mood state (Children's Depression Inventory) were also taken into account.

Hepatic encephalopathy: a dynamic or static condition

Hepatic encephalopathy (HE) is a neuropsychiatric disorder associated with portal hypertension. The mechanism of this disorder is still being characterized and the management has relied primarily on lowering the amount of ammonia present in the gastrointestinal tract or reversing liver disease by replacing the diseased liver. It is, however, not established that all the effects of hepatic encephalopathy are reversed by liver transplantation. In this review, we have outlined the mechanisms underlying HE and the pros and cons of reversibility of HE.

Screening for Early Alzheimer's Disease: Is There Still a Role for the Mini-Mental State Examination?

Background: The objective of this study was to compare the performance of the Mini-Mental State Examination (MMSE) total score as well as item scores in separating 4 groups of elderly (55-85 years of age) subjects-normal controls, subjects with mild cognitive impairment (MCI), subjects with mild Alzheimer's disease, and subjects with depression.Method: The MMSE scores of 86 subjects (25 normal elderly controls, 26 subjects with MCI, 10 subjects with mild Alzheimer's disease, and 25 subjects with depression) were analyzed. Statistically significant differences between groups in both overall MMSE score and individual item scores were documented. Receiver operating characteristic curves were constructed to yield further data.Results: The overall MMSE scores of the mild Alzheimer's disease group were significantly below those of subjects in the control, MCI, and depression groups (p < .001). The overall MMSE scores of MCI subjects were significantly lower than those of control subjects (p = .005) but not different from those of subjects with depression. Furthermore, individual item responses were not significantly different between MCI subjects and controls. The delayed recall item scores were statistically lower in the mild Alzheimer's disease group versus the other 3 groups but did not separate the control, MCI, and depression groups from each other.Conclusion: The MMSE effectively separates those with mild Alzheimer's disease from the other 3 groups and MCI from normal aging, but it is relatively ineffective in separating normal elderly individuals from those with depression and individuals with MCI from those with depression. Measures other than the MMSE may need to be implemented to evaluate mental status to more effectively separate MCI from depression and depression from normal aging.

Psychological factors and asthma quality of life: a population based study

BACKGROUND

Reports of psychological conditions in asthmatic subjects have been limited to certain population groups or convenience samples. A study was undertaken of the prevalence of psychological distress in asthma in the general population and its associations with quality of life.

METHODS

The WANTS Health and Well-being Survey is a population household interview survey of adults (age > or =18) in Western Australia, the Northern Territory, and South Australia. Data obtained were weighted to the closest census data to provide population representative estimates. Positive answers to two questions: "Have you ever been told by a doctor that you have asthma?" and "Do you still have asthma?" determined current doctor-diagnosed asthma. Other items included the SF-12, the Kessler-10 index of psychological distress, questions on feelings of lack of control in different areas of life, and on mental health conditions.

RESULTS

From the available sample of 10 080, 7619 interviews were completed (participation rate 74.8%), with 834 people reporting current doctor-diagnosed asthma (11.2%). Psychological distress was more frequent in those with asthma (17.9% v 12.2%, p<0.01) and a higher proportion with asthma were at higher risk for anxiety or depression (40.5% v 31.2%, p<0.01). Mental health conditions were also more common (16.2% v 10.8%, p<0.01), as was the frequency of those who sometimes or always felt a lack of control over their health (33.5% v 24.3%, p<0.01). People with both asthma and psychological distress had significantly lower scores on the SF-12 physical component summary (PCS) than those with either asthma or distress alone. Among those with psychological distress, mental component summary (MCS) scores did not differ between asthmatic and non-asthmatic respondents. In a multiple regression model the frequency of a feeling of lack of control over health-together with age, family's financial situation, education level, and number of days partially unable to work or perform usual duties-was significantly associated with scores on the PCS (r = 0.73, adjusted r2 = 0.54).

CONCLUSION

These results, from a representative population sample, show that psychological distress and decreased feelings of control are common in asthma and are significantly associated with physical health status.

Psychomotor retardation in elderly depressed patients

BACKGROUND

The results of previous studies on psychomotor retardation (PR) in elderly depressed patients are inconsistent. The purpose of this study was (1) to try and establish whether elderly depressed patients show PR, and (2) if so, which process (cognitive/motor or both) is mainly slowed?

METHODS

Twelve elderly depressed patients and healthy controls (age: 70) were compared on figure copying tasks in which the cognitive task difficulty was manipulated.

RESULTS

Both initiation time (IT) and movement time (MT) were prolonged in the patient group. The effects of the cognitive manipulations were not larger in the patient group.

LIMITATIONS

The sample size was small. Furthermore, patients were not medication free.

CONCLUSIONS

A cognitive and a more pronounced motor retardation was found. Clinicians should be aware of this at least additive effect of aging and depression on PR in elderly patients.

Verbal memory performance of patients with a first depressive episode and patients with unipolar and bipolar recurrent depression

Depression is usually associated with episodic memory impairment. The main clinical features of depression associated with that memory impairment are not clearly defined. The main goal of that study was to assess the role of the diagnostic subtypes and the number of depressive episodes on the memory performance of acute unipolar (UP) and bipolar (BP) depressed patients.Twenty-three patients with a first major depressive episode (FE), 28 patients meeting DSM-IV criteria for UP recurrent depression (UR) and 18 BP patients with recurrent depression were compared with 88 healthy subjects on a verbal episodic memory task. Patients suffering from a first depressive episode did not show verbal memory impairment as compared to normal controls. Unlike FE patients, UR and BP patients exhibited verbal memory deficits with impaired free recall and normal cued recall and recognition. The memory deficits of the UR and BP patients was present in the first free recall trial. Depressed patients improved their memory performance across the three trials of the task at the same rate than normal controls. Our results suggest that the number of depressive episodes has a negative influence on verbal memory performance of acute depressed patients. The effects of the repetition of the depressive episodes are not modulated by the subtypes of depression and may reflect sensitization to the cognitive impact of depression associated with increasing prefrontal dysfunction.

Cognitive dysfunction following adjuvant chemotherapy for breast cancer: two case studies

PURPOSE/OBJECTIVES

To describe the cognitive dysfunction experienced by two women after they received adjuvant chemotherapy for breast cancer and to discuss the potential role of changes in reproductive status and depression in the development of cognitive dysfunction.

DATA SOURCES

Journal articles, research data, and clinical experience.

DATA SYNTHESIS

Following chemotherapy, 17%-50% of women with breast cancer experience cognitive dysfunction that may include decrements in memory, attention, and psychomotor efficiency. One mechanism that may contribute to cognitive dysfunction involves changes in reproductive status resulting from chemotherapy. Additionally, the presence of depression may confound the experience of cognitive dysfunction.

CONCLUSIONS

A comprehensive description of cognitive dysfunction and improved understanding of the interrelationships among cognitive dysfunction, reproductive hormone levels, and depression in women with breast cancer receiving adjuvant chemotherapy may hasten the development of interventions for the management of cognitive dysfunction.

IMPLICATIONS FOR NURSING

Nurses should teach women with breast cancer and their families about the potential for cognitive dysfunction after chemotherapy so the problem can be recognized and interventions can be implemented to help women compensate for the dysfunction.

Persistence of cognitive impairment in geriatric patients following antidepressant treatment: a randomized, double-blind clinical trial with nortriptyline and paroxetine

Cognitive dysfunction is common in older persons suffering from a major depression. However, the degree to which this dysfunction is reversible with successful treatment of the depression remains uncertain. The present study examined the effects that treatment (randomized double-blind design) with either an SSRI (paroxetine) or a tricyclic antidepressant (nortriptyline) had on cognition in older depressed patients. The patients' performance was compared to that of a group of normal controls of similar age and education. Patients and controls were administered measures of working memory, information-processing speed, episodic memory and attention five times over the course of a 12 week trial. At baseline, the patients performed more poorly than the elderly controls on all cognitive measures. While the patients' performance did improve over the course of their treatment, the magnitude of this improvement did not exceed that produced in the elderly controls by practice alone. The same pattern of results was evident in both intent-to-treat and responder analyses. Thus, there was no evidence that the depressed patients' cognitive performance normalized after response to antidepressant therapy. Neither the patients' age at onset nor their baseline level of cognitive functioning influenced the amount by which their performance improved over the 12 week trial. There was no difference between paroxetine and nortriptyline in the amount of cognitive change associated with treatment. The present results suggest that cognitive dysfunction persists in older depressed patients even after their mood disorder has responded to antidepressant medications.

5-HT1A receptor knockout mouse as a genetic model of anxiety

Low levels of the serotonin(1A) (5-HT(1A)) receptor have been repeatedly found in mood and anxiety disorders. Stress often exacerbates psychiatric disease and can also reduce 5-HT(1A) receptor levels. When receptor deficiency was produced in mice by genetic knockout, an anxiety-like phenotype was observed. Anxiety in mice is defined as a high level of avoidance of novel and unfamiliar environment and increased fear reaction. Other aspects of anxiety such as autonomic activation, increased stress responsiveness, and neuroendocrine abnormalities have also been described in receptor knockout mice. These data indicate that 5-HT(1A) receptor knockout mice represent a genetic animal model of anxiety with both construct and face validities. Although the core phenotype of anxiety can be reproduced in knockout mice in various inbred and outbred backgrounds, abnormalities in 5-HT dynamics and resistance to the anxiolitic drug diazepam have been seen in one but not on other genetic backgrounds. This indicates that while the development of anxiety is an invariable consequence of receptor deficit, other features induced by receptor loss are strongly modulated by other gene(s). Strain-dependent variability within the core phenotype does not diminish the value of 5-HT(1A) receptor knockout mice as a model of anxiety. Indeed, it is consistent with the manifestation of anxiety in genetically heterogeneous human population.

Qualitative analysis of verbal fluency in depression

The aim of this study was to analyze qualitative aspects of verbal fluency in depression. Phonemic and semantic output was scored for word clustering and switching between clusters in depressed patients and normal control subjects. Depressed patients (n=25) and normal control subjects (n=19) were administered both phonemic and semantic fluency tasks. All patients were also evaluated with executive card sorting tests. Patients with depression produced fewer words on the semantic fluency task than controls and showed normal performance on the phonemic fluency tasks. The deficit on semantic fluency of depressed patients was related to a reduced number of switches with normal cluster sizes. The number of switches in depression was associated with a reduced ability to shift mental set on card sorting tests, suggesting that verbal fluency impairment reflects general executive problems in depression.