Evidence for continuing neuropsychological impairments in depression

BACKGROUND: Neuropsychological deficits have been reported in patients with major depressive disorder (MDD) during an acute episode of MDD. Little is known whether these abnormalities persist when patients are remitted. The purpose of the present study was to describe the neuropsychological functioning of fully remitted, unmedicated patients with a history of MDD by focusing on tasks related to prefrontal cortex functioning. METHODS: Twenty-eight young to middle-aged, unmedicated, fully remitted patients with MDD were compared to 23 healthy control subjects on tasks from the Cambridge Automated Neuropsychological Test Battery (CANTAB) and the California Verbal Learning Test (CVLT). RESULTS: Patients with remitted MDD relative to controls were impaired on tasks of rapid visual information processing (RVIP), psychomotor performance and spatial working memory (SWM). After correction for residual depressive symptoms, deficits in sustained attention remained significant. LIMITATIONS: CANTAB tasks are not equated for difficulty, and difficulty differences between the CANTAB tasks and the CVLT are not known. CONCLUSIONS: These findings suggest deficits in sustained attention as vulnerability marker for MDD. The functional importance of this finding and the neuronal networks involved remain to be elucidated.     

Time course for memory dysfunction in early-life and late-life major depression: A longitudinal study from the Juntendo university mood disorder project

Background

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

Methods

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

Results

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

Limitations

All patients in the present study were on antidepressant medications.

Conclusions

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

Effect of symptoms on executive function in bipolar illness

BACKGROUND: The relationship between cognitive function and symptomatology in bipolar disorder is unclear. This study assessed executive function during the manic, depressed and remitted stages of bipolar I disorder. METHOD: Tasks assessing phonological and semantic verbal fluency, the Hayling Sentence Completion Test, the Stroop Neuropsychological Screening Test and the Cognitive Estimates Test were administered to manic (n = 15), depressed (n = 15), and remitted (n = 15) bipolar I patients, and to healthy controls (n = 30). Multiple regression analyses and analyses of covariance were used to identify potential determinants of executive dysfunction in the three bipolar groups. RESULTS: Executive function deficits were particularly associated with the manic state. In general, manic patients performed less accurately than the remitted and depressed groups, and their performance deficit was related to the severity of positive thought disorder. The depressed and remitted bipolar groups showed a less widespread pattern of impairment. Deficits in response initiation, strategic thinking and inhibitory control were evident in all the bipolar groups. CONCLUSIONS: Executive function deficits in bipolar I disorder are most evident during mania, and are particularly associated with formal thought disorder. However, deficits in response initiation, strategic thinking and inhibitory control may be more related to the underlying disorder than a particular symptom profile.     

Attention and executive functions in remitted major depression patients

BACKGROUND: Although deficits in attention and executive functions in patients with Major Depressive Disorder (MDD) are well confirmed [Veiel, H.O.F., 1997. A preliminary profile of neuropsychological deficits associated with major depression. Journal of Clinical and Experimental Neuropsychology 19, 587-603.]. The database regarding the relationship between impairments and the duration of disease or the number of episodes is inconsistent. Furthermore, the role of long-term cognitive impairments in MDD during remitted state is not well understood [Elliott, R., 2002. The neuropsychological profile in primary depression. Taylor and Francis, London, pp. 273-293.]. There is consequently a lack of studies accounting for different courses of illness in the euthymic state and considering the influence of possible attentional deficits on executive performance. METHODS: 40 euthymic patients with MDD diagnosis according to DSM-IV (20 patients with 1-2 episodes and 20 severe depressives with at least three episodes) as well as 20 healthy controls matched for education and age were administered three tests for attention (attentional shift, Stroop task, sustained attention) and three for executive functions (BADS, word fluency, memory span). The methods selected were theory based with regard to an involvement of frontal-subcortical networks in MDD, attention, and executive functions, respectively. RESULTS: Euthymic patients with MDD showed deficits in all tests related to attentional and executive functions compared to healthy controls. The patient groups did not differ with regard to attentional performance. Executive functions in severe depressives were more impaired than in mild depressives. LIMITATIONS: Differing performances of the patient groups in the subtests of the executive test battery (BADS) can only be interpreted to a limited extent. CONCLUSIONS: The results support the assumption that deficits in attention and executive functions in MDD show an increase in trait character and executive function during chronic course. Implications for differential diagnosis and cognitive psychotherapy are discussed.     

抑郁症患者威斯康星卡片分类测验和连续操作测验的初步研究

目的 :通过与精神分裂症患者和正常对照的比较 ,探讨抑郁症患者的执行功能和注意功能。方法 :采用威斯康星卡片分类测验 (WCST)、连续操作测验 (CPT) ,对 66例精神分裂症患者、 42例抑郁症患者和 5 0名对照者的执行功能和注意功能进行评估。结果 :两组患者WCST中的总测验次数、持续错误数和随机错误数均明显多于对照组 (P <0 0 1) ;其中精神分裂症组WCST的三项成绩明显差于抑郁症组 (P <0 0 1) ;无干扰刺激时 ,精神分裂症组的认对数明显差于抑郁症组和对照组 (P <0 0 1) ,而抑郁症组与对照组之间的差异无显著性 (P >0 0 5 ) ;有干扰刺激时 ,精神分裂症组与对照组的差异有显著性 (P <0 0 1) ,抑郁症组与其它两组的差异均无显著性 (P >0 0 5 )。结论 :抑郁症组有执行功能障碍 ,介于精神分裂症组和对照组之间 ;在抑郁症组中没有发现有明显的注意障碍。     

Treatment response in late-onset depression: relationship to neuropsychological, neuroradiological and vascular risk factors

BACKGROUND: Late-onset depressive disorder is associated with white matter lesions and neuropsychological deficits that in some studies are linked to a poorer outcome for depression. Some white matter lesions may be vascular in origin. This study investigated the relationship between response or non-response to antidepressant monotherapy and neuropsychological function, structural brain measures and vascular factors. METHOD: This was a case control study. Fifty patients with late-onset major depressive disorder (29 who were responders to antidepressant monotherapy and 21 who were not) were compared with 35 non-depressed control subjects. Measures included assessment of vascular risk factors, neuropsychological testing and a magnetic resonance imaging (MRI) scan. RESULTS: After adjustment for depressed mood and medication at evaluation, both patient groups had significantly more impairment compared to control subjects on verbal learning tasks involving immediate or delayed recall. Patients who did not respond to antidepressant monotherapy had significantly poorer performance than controls on tests involving visuospatial ability, language, word recognition and tests of executive function, whereas there were no differences between control subjects and responders. On two tests of executive function (verbal fluency and the Stroop test) non-responders scored significantly worse than responders. There were no significant group differences on MRI measures of atrophy or of white matter lesions apart from a higher periventricular hyperintensity score in non-responders compared to controls. There were no group differences on measures of vascular disease. CONCLUSION: The results lend support to the emerging evidence that resistance to treatment in late-onset depression may be associated with impaired executive function. Subtle cerebrovascular mechanisms may be involved.     

Sex differences in physiological and affective responses to stress in remitted depression

Major depressive disorder (MDD) is associated with alterations in stress physiology. Severe melancholic depression is characterized by hypercortisolism, but community dwelling mildly depressed individuals and those with remitted MDD have shown reduced or normal reactivity to stress. There are also pronounced sex differences both in the incidence of MDD and in stress reactivity. To explore the relationships among depression history, sex differences, and stress, we examined stress reactivity in people with and without a history of MDD. Twenty-two participants with remitted MDD (12 men and 10 women) and 36 never depressed comparison participants (22 men and 14 women) participated in the study. Cortisol and alpha-amylase (sAA) were sampled from saliva before, 10 min after, and 30 min after the Trier Social Stress Test (TSST). Participants filled out the Positive Affect Negative Affect Schedule (PANAS) before and after they underwent the TSST. Women with remitted MDD showed reduced cortisol response to the TSST compared with the never MDD women, while men with remitted MDD showed comparable cortisol reactivity to the never depressed men. The groups did not differ on sAA reactivity to stress. The remitted MDD group (overall and men and women separately) reported greater negative affect both before and after stress compared to the never depressed group. Women from both groups reported greater post-stress negative affect than men. In contrast, men from both groups reported higher positive affect before and after stress than women. Given that the sex difference findings were not dependent on depression history, self-reported affective differences in response to stress may predate depressive symptoms and contribute to sex differences in depression incidence.     

Combined dexamethasone/CRF test in remitted outpatients with recurrent major depressive disorder

BACKGROUND: Hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis is a prominent neurobiological finding during a major depressive episode, reflecting a state dependent factor. An issue under investigation is whether the dysfunction of the HPA axis has also a role to play as a state-independent or trait factor for major depressive disorder (MDD). In relation to this, it is important to examine HPA axis function in patients who are clinically remitted from depression. METHODS: Twenty-three remitted outpatients with recurrent MDD and 23 age- and gender-matched control individuals without a history of MDD participated in the sensitive combined dexamethasone/corticotropin-releasing factor (DEX/CRF) test. RESULTS: Free salivary cortisol responses were not significantly different between the two groups, although three patients (13%) displayed extremely elevated cortisol responses after CRF. LIMITATIONS: Limited sample size. All but one patient were under treatment with an antidepressant. CONCLUSIONS: This study shows no evidence for a disturbed DEX/CRF test as a state-independent factor in recurrent MDD on a group level. However, MDD is a complex and heterogenic disorder. Probably, there is a subgroup of patients who show a disturbed DEX/CRF test due to an inherited and/or acquired predisposition or as a biological scar after previous depressive episodes.     

Neural basis of the emotional Stroop interference effect in major depression

BACKGROUND: A mood-congruent sensitivity towards negative stimuli has been associated with development and maintenance of major depressive disorder (MDD). The emotional Stroop task assesses interference effects arising from the conflict of emotional expressions consistent with disorder-specific self-schemata and cognitive colour-naming instructions. Functional neuroimaging studies of the emotional Stroop effect advocate a critical involvement of the anterior cingulate cortex (ACC) during these processes. METHOD: Subjects were 17 medication-free individuals with unipolar MDD in an acute depressive episode (mean age 39 years), and 17 age-, gender- and IQ-matched healthy volunteers. In an emotional Stroop task, sad and neutral words were presented in various colours, and subjects were required to name the colour of words whilst undergoing functional magnetic resonance imaging (fMRI). Overt verbal responses were acquired with a clustered fMRI acquisition sequence. RESULTS: Individuals with depression showed greater increases in response time from neutral to sad words relative to controls. fMRI data showed a significant engagement of left rostral ACC (BA 32) and right precuneus during sad words in patients relative to controls. Additionally, rostral ACC activation was positively correlated with latencies of negative words in MDD patients. Healthy controls did not have any regions of increased activation compared to MDD patients. CONCLUSIONS: These findings provide evidence for a behavioural and neural emotional Stroop effect in MDD and highlight the importance of the ACC during monitoring of conflicting cognitive processes and mood-congruent processing in depression.     

Categoric overgeneral autobiographical memory in adolescents with major depressive disorder

BACKGROUND: Categoric, overgeneral autobiographical memory is more common in depressed adults than controls and predicts persistence of depression. This cross-sectional study investigated whether, compared with non-depressed psychiatric cases and community controls, first episode major depressive disorder (MDD) in adolescents is associated with categoric overgeneral memory retrieval. METHODS: Ninety-six clinically referred adolescents (aged 12-17 years) with MDD, 26 non-depressed psychiatric cases and a sample of 33 community controls were recruited. All subjects were assessed using the Kiddie-Schedule for Schizophrenia and Affective Disorders, and completed Williams' cued Autobiographical Memory Test and the Mood and Feelings Questionnaire. Hamilton Depression Rating Scales were completed with MDD subjects, as an index of depression severity. RESULTS: Adolescents with current first episode MDD retrieved more categoric overgeneral memories than controls, but not than non-depressed psychiatric cases. Adolescents in full remission from a recent episode of MDD retrieved more categoric memories to positive cues than controls. Categoric memory in MDD was related to observer-rated and self-reported severity, but not to the pattern of co-morbid diagnoses. There were negative correlations between IQ and categoric memories in both clinical cases and controls. A positive correlation between categoric memory to negative cues and self-reported depressive symptoms was found in clinical cases (but not controls). CONCLUSIONS: In adolescents, increased categoric overgeneral memory is associated with, but not specific to first episode MDD. Positive categoric memories are also increased in fully remitted MDD as compared to controls.     

Electrophysiological evidence for abnormal error monitoring in recurrent major depressive disorder

Previous neuroimaging work has identified anterior cingulate cortex (ACC) abnormalities in recurrent major depressive disorder (MDD), implicating a persistent underlying predisposition to depression. Error-monitoring studies in MDD, as indexed by error-related negativity (ERN), have yielded conflicting results, probably because of task differences or confounds in patient samples. ERN patterns were examined in remitted (n=19) and acutely depressed (n=17) patients, classified as a function of illness stage, and their matched controls in a go/no-go task using high-density ERPs. Results showed an abnormally larger ERN (p<.05) in remitted patients, especially in younger cases. Overall, ERN was found to decrease with age across all groups. The findings of increased ERN in remitted depression may implicate an overactive ACC associated with a hypervigilant error-monitoring system. The observed tendency of ERN reduction in a severe depressive state failed to reach statistical significance.     

No strong evidence for abnormal levels of dysfunctional attitudes,automatic thoughts,and emotional information‐processing biases in remitted bipolar I affective disorder

Introduction . Beck extended his original cognitive theory of depression by suggesting that mania was a mirror image of depression characterized by extreme positive cognition about the self, the world, and the future. However, there were no suggestions what might be special regarding cognitive features in bipolar patients ( Mansell & Scott, 2006 ). We therefore used different indicators to evaluate cognitive processes in bipolar patients and healthy controls. Methods . We compared 19 remitted bipolar I patients (BPs) without any Axis I comorbidity with 19 healthy individuals (CG). All participants completed the Beck Depression Inventory, the Dysfunctional Attitude Scale, the Automatic Thoughts Questionnaire, the Emotional Stroop Test, and an incidental recall task. Results . No significant group differences were found in automatic thinking and the information‐processing styles (Emotional Stroop Test, incidental recall task). Regarding dysfunctional attitudes, we obtained ambiguous results. Conclusions . It appears that individuals with remitted bipolar affective disorder do not show cognitive vulnerability as proposed in Beck's theory of depression if they only report subthreshold levels of depressive symptoms. Perhaps, the cognitive vulnerability might only be observable if mood induction procedures are used.     

缓解期重性抑郁与心境恶劣患者人格特征及人格障碍研究

目的：研究重性抑郁症(MDD)和心境恶劣障碍(DD)患者在人格维度、人格特质水平及人格模型及人格障碍倾向性方面的特征。方法：采用NEO-PI-R个性调查表及人格诊断问卷(PDQ^ 4)对58例MDD和57例DD患者及115例正常人进行测试。结果：MDD和DD在NEO-PI-R的五因素人格模型的外向性、严谨性得分均低于正常组，DD患者的神经质分高于MDD患者，MDD患者的顺同性分高于正常组；在30个特质层面上，MDD和DD与正常组之间有显著性差异，DD患者的N1(焦虑)、N4(自我意识)分明显高于MDD患者，E4(热情性)、A1(信任感)分明显低于MDD患者；MDD和DD在PDQ^ 4的边缘型(BDL)、回避型(AVD)、抑郁型(DEP)、分裂性(SZD)、偏执型(PND)、强迫型(OBC)人格障碍得分明显高于正常组，DD患者在分裂型得分明显高于MDD患者，在表演型(HST)分明显高于正常组。结论：MDD和DD的人格特征既有共同的之处，也存在差异。两者均伴有人格障碍，但DD患者比MDD患者人格障碍更明显。     

Cognitive inefficiency in depressive undergraduates: stroop processing and ERPs

Evidence from neuroimaging studies indicates that depressive symptomatology is associated with inefficient recruitment of prefrontal brain regions while performing tasks that tax executive function. In the current study, we investigated the time-course and ERP signature of inefficient executive functioning using a verbal Stroop color-naming task. Twenty (20) undergraduates with moderate to severe BDI-II depression scores and 20 low-scoring controls completed the task. Performance measures did not differ between the two groups. Overt reaction and P300 latencies indicated that all participants showed prominent Stroop effects, such that incongruent responses were delayed compared to congruent. Effects of task condition on the frontal N450 indicated that depressive participants differentiated congruent and incongruent trials earlier than did controls, and that the size of the congruency effect on the N450 was related to self-reported trait rumination among depressive participants. Following this effect, depressive participants showed larger P300s, suggesting an over-commitment of cognitive control resources in the depressive participants. These data lend further evidence to the cortical inefficiency hypothesis and extend the literature by indicating possible improper timing of neural activations during an executive task in depressive undergraduates.     

Is interpersonal sensitivity specific to non-melancholic depressions?

Background: We investigated whether melancholic and non-melancholic Japanese depressive patients differed in regard to a personality feature, interpersonal sensitivity, as measured by the Interpersonal Sensitivity Measure (IPSM). Methods: In addition to 154 normal controls, 66 remitted melancholic patients and 55 remitted non-melancholic patients filled out the IPSM and two widely-used comprehensive personality inventories, the Temperament and Character Inventory (TCI) and the Munich Personality Test (MPT). The subdivision of patients was made according to three major symptom-based criteria for melancholia (those of RDC, DSM-III, DSM-IV). Results: Multivariate and post-hoc univariate analyses of variance revealed significant differences among the three groups in several personality dimensions after Bonferroni's adjustments of P values. While reported scores of both melancholic and non-melancholic patients deviated from normative scores on several personality dimensions, non-melancholic patients reported significantly higher scores on the total IPSM and the 'fragile inner-self' (a subscore of the IPSM) than did normal controls or melancholic depressives. The principal component analysis isolated two factors related to depressive disorders: one factor corresponding to the five IPSM scores; and the other corresponding to harm avoidance, neuroticism and frustration tolerance. The scores on the former factor differentiated non-melancholic depressives from melancholic depressives and normal controls. The scores on the latter factor differentiated both melancholic and non-melancholic depressives from normal controls. Limitations: Prospective studies in which depressive subjects are subdivided into melancholic and non-melancholic subjects will be required to see whether the personality deviations here related to depressive disorders strongly reflect the premorbid personality function. Conclusions: These results indicate that the IPSM scales (particularly, the fragile inner-self scale and the total IPSM scale) are relatively independent of all dimensions included in the two comprehensive personality inventories, and have a capability to describe personality differences between non-melancholic depression and melancholia.     

Cognitive functioning in a population-based sample of young adults with a history of non-psychotic unipolar depressive disorders without psychiatric comorbidity

BACKGROUND: There is evidence for cognitive dysfunction in unipolar depression among middle-aged and elderly patients, but cognitive functioning among depressed young adults has scarcely been systematically investigated. The aims of the present study were to examine cognitive functioning among depressed young adults identified from the general population and to determine whether cognitive deficits vary as a function of different disorder characteristics, such as severity and age at onset. METHODS: Performance in verbal and visual short-term memory, verbal long-term memory and learning, attention, processing speed, and executive functioning was compared between a population-based sample of 21-35-year-olds with a lifetime history of non-psychotic unipolar depressive disorders without psychiatric comorbidity (n=68) and healthy controls derived from the same population (n=70). RESULTS: Depressed young adults were not found to be impaired in any of the assessed cognitive functions, except for some suggestion of mildly compromised verbal learning. Nevertheless, younger age at depression onset was associated with more impaired executive functioning. LIMITATIONS: The results may slightly underestimate of the true association between depression and cognitive impairments in the young adult population due to possible dropout of participants. Additionally, the problem of multiple testing was not entirely corrected. CONCLUSION: The findings from this study indicate that a lifetime history of non-psychotic unipolar depressive disorders among young adults without psychiatric comorbidity may be associated only with minimal cognitive deficits, even when some residual depressive symptoms are prevalent. However, early-onset depression may represent a more severe form of the disorder, associated with more cognitive dysfunction.     

Is Insomnia a Perpetuating Factor for Late-Life Depression in the IMPACT Cohort?

STUDY OBJECTIVES: Insomnia and depressive disorders are significant health problems in the elderly. Persistent insomnia is a risk factor for the development of new-onset and recurrent major depressive disorder (MDD). Less clear is whether persistent insomnia may perpetuate MDD andlor dysthymia. The present longitudinal study examines the relationship of insomnia to the continuation of depression in the context of an intervention study in elderly subjects. DESIGN: Data were drawn from Project IMPACT, a multisite intervention study, which enrolled 1801 elderly patients with MDD and/or dysthymia. In the current study, subjects were assigned to an insomnia-status group (Persistent, Intermediate, and No Insomnia) based on insomnia scores at both baseline and 3-month time points. Logistic regressions were conducted to determine whether Persistent Insomnia was prospectively associated with increased risk of remaining depressed and/or achieving a less than 50% clinical improvement at 6 and at 12 months compared with the No Insomnia reference group. The Intermediate Insomnia group was compared with the other 2 groups to determine whether a dose-response relationship existed between insomnia type and subsequent depression. SETTING: Eighteen primary clinics in 5 states. PARTICIPANTS: Older adults (60+) with depression. MEASUREMENTS AND RESULTS: Overall, patients with persistent insomnia were 1.8 to 3.5 times more likely to remain depressed, compared with patients with no insomnia. The findings were more robust in patients receiving usual care for depression than in patients receiving enhanced care. Findings were also more robust in subjects who had MDD as opposed to those with dysthymia alone. CONCLUSIONS: These findings suggest that, in addition to being a risk factor for a depressive episode, persistent insomnia may serve to perpetuate the illness in some elderly patients and especially in those receiving standard care for depression in primary care settings. Enhanced depression care may partially mitigate the perpetuating effects of insomnia on depression.     

首发与复发性抑郁症患者执行功能的比较

目的比较首发与复发性抑郁症患者的认知执行功能。方法对43例首发抑郁症患者以及48例复发抑郁症患者,采用17项汉密尔顿抑郁量表测定抑郁严重程度,采用威斯康星卡片分类测验测定执行功能,并进行治疗前后的执行功能比较。结果治疗前首发组与复发组各项执行功能指标均较对照组差（P〈0.05）;分类数首发组高于复发组（P〈0.05）。治疗后首发组除分类数外,其它指标均与对照组有统计学差异（P〈0.05）;复发组各项指标仍较对照组为差（P〈0.05）;首发组与复发组治疗后比较,各项指标首发组均优于复发组（P〈0.05）;治疗后,无论是首发组还是复发组,其HAMD17评分及执行功能的各项指标均有显著性改善（P〈0.05）。结论首发与复发性抑郁症患者均存在执行功能的损害;复发性抑郁症患者的执行功能损害更为严重。药物治疗后,首发、复发性抑郁症患者执行功能均有一定程度的恢复。     

Executive dysfunction and visuospatial ability among depressed elders in a community setting.

Visuospatial ability is frequently compromised among elderly depressed patients, but it is unclear whether the impairment is a consequence of a visuospatial memory deficit or of an executive dysfunction that impacts visuospatial ability. The Boston Qualitative Scoring System is a method of scoring the Rey-Osterrieth Complex Figure (ROCF) that assesses the process used to draw the figure, the executive aspect of the task, as well as the accuracy and location of the completed elements. The hypotheses that executive scores as measured by the BQSS would separate diagnostic groups and that executive function would mediate the relationship between depression and nonverbal recall were tested using a between groups design with elderly depressed volunteers (N = 31) and healthy controls (N = 31). Participants were screened for other Axis I disorders with the Structured Clinical Interview for DSM-IV Diagnosis, diagnosed for major depression per DSM-IV criteria, and administered the ROCF. The copy and recall drawings were scored using BQSS criteria, and scores were grouped into executive and drawing scores from both copy and recall phases. Executive scores during the copy phase and drawing scores from the recall phase separated the diagnostic groups [F(1,59), = 4.14, P = .05] and [F(1,59) = 6.88, P = .01], respectively. Follow-up ANCOVAS showed that copy Planning, the score that quantified the process by which the figure was drawn, separated the diagnostic groups. Planning also mediated the association between depression and the percent of the figure recalled after the short delay (Z = 1.84, P < .05). The significance of the depression-to-recall pathway was eliminated when Planning was controlled for, but Planning remained related to percent recalled [B = -6.90, P < .007]. A dimension of executive dysfunction, represented here by Planning, may be one underlying source of the observed decline in nonverbal recall among elderly depressed patients. This result is consistent with the theory that dysfunction of the prefrontal cortex is a critical feature of late-life depression.     

Cognitive deficits in the remitted state of unipolar depressive disorder

Background: Patients with unipolar depressive disorder may present with cognitive deficits in the remitted state, and the aim of the present study was to investigate whether cognitive deficits within specific cognitive domains are present. Method: Via the Danish registers (Civil Person Register, Danish Psychiatric Register) we identified individuals between 40 and 80 years of age with a diagnosis of unipolar disorder at their first discharge from a psychiatric hospital, and a gender- and age-matched control group. Particular emphasis was placed on assuring that patients were in a remitted state. Cognitive function was assessed with a broad range of neuropsychological tests. Results: A total of 88 patients and 50 controls were included in the study. In multiple linear regression analyses with simultaneous adjustment for age, gender, education level, premorbid IQ, and residual depressive symptoms, a diagnosis of unipolar disorder predicted lower performance on the Trail Making Test, the Symbol Digit Modalities Test, and on the Stroop test. Conclusion: Cognitive deficits are present in patients with unipolar disorder in the remitted state. The deficits seem to reside more within the cognitive domain of attention than within other domains, and may be characterized by impairment of processing speed and cognitive flexibility. (PsycINFO Database Record (c) 2012 APA, all rights reserved).