Some aspects of memory disorders clearly distinguish dementia of the Alzheimer's type from depressive pseudo-dementia

Exploring depression in Alzheimer's disease: an Italian Delphi Consensus on phenomenology, diagnosis, and management

BACKGROUND

In Alzheimer's disease (AD), the progressive cognitive impairment is often combined with a variety of neuropsychiatric symptoms, firstly depression. Nevertheless, its diagnosis and management is difficult, since specific diagnostic criteria and guidelines for treatment are still lacking. The aim of this Delphi study is to reach a shared point of view among different Italian specialists on depression in AD.

METHODS

An online Delphi survey with 30 questions regarding epidemiology, diagnosis, clinical features, and treatment of depression in AD was administered anonymously to a panel of 53 expert clinicians.

RESULTS

Consensus was achieved in most cases (86%). In the 80% of statements, a positive consensus was reached, while in 6% a negative consensus was achieved. No consensus was obtained in 14%. Among the most relevant findings, the link between depression and AD is believed to be strong and concerns etiopathogenesis and phenomenology. Further, depression in AD seems to have specific features compared to major depressive disorder (MDD). Regarding diagnosis, the DSM 5 diagnostic criteria for MDD seems to be not able to detect the specific aspects of depression in AD. Concerning treatment, antidepressant drugs are generally considered the main option for depression in dementia, according to previous guidelines. In order to limit side effects, multimodal and SSRI antidepressant are preferred by clinicians. In particular, the procognitive effect of vortioxetine seems to be appealing for the treatment of depression in AD.

CONCLUSIONS

This study highlights some crucial aspects of depression in AD, but more investigations and specific recommendations are needed.

[Old and depressed and/or demented? - Pseudodepression vs. pseudodementia]

Many elderly patients suffer from both, depressive symptoms and cognitive deficits. Clinically, it oftentimes appears unclear whether the affective or the cognitive problems are primary or secondary. Modern molecular and imaging markers contribute to a more efficient distinction between depression and incipient dementia due to neurodegenerative, vascular, and other diseases. A careful history and clinical investigations are necessary to identify the underlying diseases, but they do not always offer sufficient therapeutic guidance. If in doubt, the condition should always be considered as potentially reversible and treated emphatically (but with age-appropriate caution).

Pseudodementia, pseudo-pseudodementia, and pseudodepression

Dementia has a wide range of reversible causes. Well known among these is depression, though other psychiatric disorders can also impair cognition and give the appearance of neurodegenerative disease. This phenomenon has been known historically as "pseudodementia." Although this topic attracted significant interest in the 1980s and 1990s, research on the topic has waned. In this paper, we consider reasons for this decline, including objections to the term itself and controversy about its distinctness from organic dementia. We discuss limitations in the arguments put forward and existing research, which, crucially, does not support inevitable progression. We also discuss other neglected masquerades, such as of pseudodementia itself ("pseudo-pseudodementia") and depression ("pseudodepression"). Based on this reappraisal, we argue that these terms, while not replacing modern diagnostic criteria, remain relevant as they highlight unique groups of patients, potential misdiagnosis, and important, but neglected, areas of research.

Functional cognitive disorders: a systematic review

Cognitive symptoms are common, and yet many who seek help for cognitive symptoms neither have, nor go on to develop, dementia. A proportion of these people are likely to have functional cognitive disorders, a subtype of functional neurological disorders, in which cognitive symptoms are present, associated with distress or disability, but caused by functional alterations rather than degenerative brain disease or another structural lesion. In this Review, we have systematically examined the prevalence and clinical associations of functional cognitive disorders, and related phenotypes, within the wider cognitive disorder literature. Around a quarter of patients presenting to memory clinics received diagnoses that might indicate the presence of functional cognitive disorders, which were associated with affective symptoms, negative self-evaluation, negative illness perceptions, non-progressive symptom trajectories, and linguistic and behavioural differences during clinical interactions. Those with functional cognitive disorder phenotypes are at risk of iatrogenic harm because of misdiagnosis or inaccurate prediction of future decline. Further research is imperative to improve diagnosis and identify effective treatments for functional cognitive disorders, and better understanding these phenotypes will also improve the specificity of diagnoses of prodromal degenerative brain disease.

Predicting progression to Alzheimer's disease in subjects with amnestic mild cognitive impairment using performance on recall and recognition tests

The research of reliable procedures for predicting cognitive decline or stability in persons with amnestic mild cognitive impairment (a-MCI) is a major goal for the early identification of subjects in the prodromal stages of dementia. The aim of this study was to evaluate whether different memory performances on two procedures commonly used for the neuropsychological assessment of episodic memory (i.e., free recall and recognition) might be a key in predicting a-MCI patients' subsequent progression to Alzheimer's disease (AD). For this purpose, 80 patients diagnosed with a-MCI at the first assessment and followed-up for at least 3 years were included. During this time, 41 subjects remained in a stable condition of cognitive impairment or improved (stable-MCI) and 39 patients converted to AD dementia (converter-MCI). Sixty-two age- and education-matched healthy individuals were also recruited as healthy controls (HC). Baseline memory performance on the free recall (5th immediate and 15-min delayed) and yes/no recognition (the sensitivity measure d') of a 15-word list were analyzed. Results showed that stable-MCIs forgot significantly more information from immediate to delayed recall of the word list than HC, but exhibited a pronounced improvement of memory performance in the recognition test format. On the contrary, converter-MCIs showed diminished sensitivity in benefiting from cues for recognizing studied words. Word list recognition correctly classified group membership with good overall accuracy, which was higher compared to the classification of converter and stable a-MCIs provided by free recall; therefore, it could be a useful diagnostic tool for predicting progression to AD dementia from the prodromal stage.

The Hopkins Verbal Learning Test: an in-depth analysis of recall patterns

One of the earliest signs of dementia is memory issues and verbal word lists, such as the Hopkins Verbal Learning Test (HVLT), are successfully used for screening. To gain insight in how memory is affected in dementia, and to further improve the efficacy of the HVLT, in-depth analysis of the recall patterns of dementia cases and controls was conducted. Dementia cases and controls were matched for factors that can affect performance, such as age, gender and education level. Word frequency, syllable length, and orthographic neighbourhood size did not differ in the Indonesian version of the HVLT, nor did these characteristics affect recall. However dementia cases showed consistent and poor recall across the three trials; with the worst recall for the "human shelter" category and best recall for the "animals" category. Dementia cases also showed impaired accessibility of all categories with reduced subsequent recall from accessed categories and reduced primacy and recency levels. Finally, dementia cases exhibited lower levels of re-remembering and recalling new words, and higher levels of immediate forgetting and never recalling words. It was concluded that utilising the extra information provided by the in-depth analyses of the recall patterns could be beneficial to improve dementia screening.

Verbal list learning and memory profiles in HIV-infected adults, Alzheimer's disease, and Parkinson's disease: An evaluation of the "cortical hypothesis" of NeuroAIDS

HIV+ population is getting older because of progress in treatments. Yet, there are concerns that Older HIV+ individuals (OHIV+) may be more vulnerable for developing a "cortical" dementia such as Alzheimer Disease (AD). Our aim was to explore the hypothesis that the cognitive deficit extends to ''cortical'' functions in OHIV+ by comparing serial position effects (SPE) in different groups of participants affected by "cortical" or "subcortical" damage. We enrolled a total of 122 subjects: 22 OHIV+ (≥60 years of age), 31 Younger HIV+ (YHIV+) (<60 years of age), 18 participants with AD, 23 subjects with Parkinson Disease (PD), and 28 healthy subjects. All subjects performed verbal learning tasks (VLT) to explore SPE. Factorial analysis of covariance showed a significant effect of "group" (p < 0.001) and "task" (Primacy vs Recency) (p < 0.001), but no significant group*task (p = 0.257) interaction. Compared with healthy subjects (p = 0.003), AD had the most severe reduction of Primacy, confirming a primary "encoding deficit," while PD confirmed a "frontal pattern." OHIV+ showed a memory profile similar to that of PD with a worsening of the cognitive performance in comparison with YHIV+. In conclusion, we did not confirm the "cortical" hypothesis in OHIV+, at least in terms of learning and memory functions.

Depressive Mood and Testosterone Related to Declarative Verbal Memory Decline in Middle-Aged Caregivers of Children with Eating Disorders

Caring for children diagnosed with a chronic psychological disorder such as an eating disorder (ED) can be used as a model of chronic stress. This kind of stress has been reported to have deleterious effects on caregivers’ cognition, particularly in verbal declarative memory of women caregivers. Moreover, high depressive mood and variations in testosterone (T) levels moderate this cognitive decline. The purpose of this study was to characterize whether caregivers of individuals with EDs (n = 27) show declarative memory impairments compared to non-caregivers caregivers (n = 27), using for this purpose a standardized memory test (Rey’s Auditory Verbal Learning Test). Its purpose was also to examine the role of depressive mood and T in memory decline. Results showed that ED caregivers presented high depressive mood, which was associated to worse verbal memory performance, especially in the case of women. In addition, all caregivers showed high T levels. Nonetheless, only in the case of women caregivers did T show a curvilinear relationship with verbal memory performance, meaning that the increases of T were associated to the improvement in verbal memory performance, but only up to a certain point, as after such point T continued to increase and memory performance decreased. Thus, chronic stress due to caregiving was associated to disturbances in mood and T levels, which in turn was associated to verbal memory decline. These findings should be taken into account in the implementation of intervention programs for helping ED caregivers cope with caregiving situations and to prevent the risk of a pronounced verbal memory decline.

Linking CSF and cognition in Alzheimer's disease: Reanalysis of clinical data

OBJECTIVES

Memory and executive deficits are important cognitive markers of Alzheimer's disease (AD). Moreover, in the past decade, cerebrospinal fluid (CSF) biomarkers have been increasingly utilized in clinical practice. Both cognitive and CSF markers can be used to differentiate between AD patients and healthy seniors with high diagnostic accuracy. However, the extent to which performance on specific mnemonic or executive tasks enables reliable estimations of the concentrations of different CSF markers and their ratios remains unclear.

METHODS

To address the above issues, we examined the association between neuropsychological data and CSF biomarkers in 51 AD patients using hierarchical multiple regression analyses. In the first step of these analyses, age, education and sex were entered as predictors to control for possible confounding effects. In the second step, data from a neuropsychological test battery assessing episodic memory, semantic memory and executive functioning were included to determine whether these variables significantly increased (compared to step 1) the explained variance in Aβ42 concentration, p-tau concentration, t-tau concentration, Aβ42/t-tau ratio, and Aβ42/Aβ40 ratio.

RESULTS

The different models explained 52% of the variance in Aβ42/t-tau ratio, 27% of the variance in Aβ42 concentration, and 28% of the variance in t-tau concentration. In particular, Aβ42/t-tau ratio was associated with verbal recognition and code shifting, with Aβ42 being related to verbal recognition and t-tau being related to code shifting. By contrast, the inclusion of neuropsychological data did not allow reliable estimations of Aβ42/Aβ40 ratio or p-tau concentration.

CONCLUSION

Our results showed that strong associations exist between the cognitive key symptoms of AD and the concentrations and ratios of specific CSF markers. In addition, we revealed a specific combination of neuropsychological tests that may facilitate reliable estimations of CSF concentrations, thereby providing important diagnostic information for non-invasive early AD detection.

Poder preditivo do MoCa na avaliação neuropsicológica de pacientes com diagnóstico de demência

O estudo teve como objetivo correlacionar testes neuropsicométricos em idosos com mais de quatro anos de escolaridade e avaliar a acurácia do MoCA no diagnóstico da doença de Alzheimer (DA) e comprometimento cognitivo leve (CCL). Foram avaliados 136 idosos atendidos no Instituto de Geriatria e Gerontologia, no período de abril de 2010 a dezembro de 2012. Os instrumentos utilizados foram o Miniexame do Estado Mental (MEEM), Cambridge Cognitive Examination (CAMCOG), teste do Desenho do Relógio (TDR), teste de Fluência Verbal, Escala de Depressão Geriátrica e Questionário de Atividades Funcionais de Pfeffer (QAFP), além do teste Montreal Cognitive Assessment (MoCA). Foi utilizada a análise de curva ROC para se estabelecer pontos de corte, e o coeficiente de correlação de Pearson, a fim de comparar o MoCA com os outros testes. Os resultados mostraram que o teste MoCA foi o melhor para diferenciar doença de Alzheimer dos casos de CCL. A sensibilidade e a especificidade encontradas foram, respectivamente, 82,2% e 92,3%. A análise do teste de correlação evidenciou que o MoCA se correlacionou fortemente com outros testes já validados e de ampla aplicação no Brasil. Pode-se concluir que o MoCA mostrou ser o teste com maior valor preditivo para diferenciar DA de CCL e também diferenciar CCL dos controles normais. Além disso, o MoCA se correlacionou de maneira significativa com a variável idade e os testes MEEM, CAMCOG, TDR, de Fluência Verbal e QAFP, instrumentos já validados e amplamente utilizados no Brasil.

Serial position effects in patients with mild cognitive impairment and early and moderate Alzheimer's disease compared with healthy comparison subjects

BACKGROUND/AIMS

This study aimed to investigate whether the serial position effects in memory can differentiate patients with different subtypes of mild cognitive impairment (MCI) from healthy controls and patients with different stages of Alzheimer's disease (AD).

METHODS

The serial position effects was tested with the CERAD word list task in 184 persons (39 healthy control subjects, 15 amnestic MCI single domain subjects, 23 amnestic MCI multiple domain subjects, 31 nonamnestic MCI subjects, 45 early or mild AD patients, and 31 moderate AD patients).

RESULTS

With progression of dementia, memory deficits increased and the impairment in the primacy effect during the learning trials advanced, whereas the recall of recent items was less impaired. The serial position profile of nonamnestic MCI patients resembled that of healthy control subjects, whereas amnestic MCI patients showed poorer performance in all 3 positions but no significant difference as a function of serial word position.

CONCLUSION

Analyses of the serial position effect may be a useful complement to clinical neuropsychological measures for distinguishing amnestic MCI patients from normal aging and patients with different stages of dementia.

Establishing robust cognitive dimensions for characterization and differentiation of patients with Alzheimer's disease, mild cognitive impairment, frontotemporal dementia and depression

OBJECTIVE

The diagnosis of mild cognitive impairment (MCI) and dementia requires detailed neuropsychological examinations. These examinations typically yield a large number of outcome variables, which may complicate the interpretation and communication of results. The purposes of this study were the following: (i) to reduce a large data set of interrelated neuropsychological variables to a smaller number of cognitive dimensions; (ii) to create a common metric for these dimensions (z-scores); and (iii) to study the ability of the cognitive dimensions to distinguish between groups of patients with different types of cognitive impairment.

METHODS

We tested 1646 patients with different forms of dementia or with a major depression with a standard (n = 632) or, if cognitively less affected, a challenging neuropsychological battery (n = 1014). To identify the underlying cognitive dimensions of the two test batteries, maximum likelihood factor analyses with a promax rotation were conducted. To interpret the sum scores of the factors as standard scores, we divided them by the standard deviation of a cognitively healthy sample (n = 1145).

RESULTS

The factor analyses yielded seven factors for each test battery. The cognitive dimensions in both test batteries distinguished patients with different forms of dementia (MCI, Alzheimer's dementia or frontotemporal dementia) and patients with major depression. Furthermore, patients with stable MCI could be separated from patients with progressing MCI. Discriminant analyses with an independent new sample of patients (n = 306) revealed that the new dimension scores distinguished new samples of patients with MCI from patients with Alzheimer's dementia with high accuracy.

CONCLUSION

These findings suggest that these cognitive dimensions may benefit neuropsychological diagnostics.

Serial position effects in Alzheimer's disease, mild cognitive impairment, and normal aging: predictive value for conversion to dementia

Serial position effects in word list learning have been used to differentiate normal aging and dementia. Prominent recency and diminished primacy have consistently been observed in Alzheimer's disease (AD). We examined serial position effects in patients with mild cognitive impairment (MCI), in patients with AD, and in normal healthy controls. Additionally, we classified MCI patients into those who progressed to AD (MCI-p) and those who did not (MCI-np). We compared two serial position measures: regional and standard scores. Regional scores, mainly the primacy effect, improved discrimination between MCI and controls and between MCI-np and MCI-p, proving to be more sensitive and specific than the recency effect.

Immediate list recall as a measure of short-term episodic memory: insights from the serial position effect and item response theory

The serial position effect shows that two interrelated cognitive processes underlie immediate recall of a supraspan word list. The current study used item response theory (IRT) methods to determine whether the serial position effect poses a threat to the construct validity of immediate list recall as a measure of verbal episodic memory. Archival data were obtained from a national sample of 4,212 volunteers aged 28-84 in the Midlife Development in the United States study. Telephone assessment yielded item-level data for a single immediate recall trial of the Rey Auditory Verbal Learning Test (RAVLT). Two parameter logistic IRT procedures were used to estimate item parameters and the Q(1) statistic was used to evaluate item fit. A two-dimensional model better fit the data than a unidimensional model, supporting the notion that list recall is influenced by two underlying cognitive processes. IRT analyses revealed that 4 of the 15 RAVLT items (1, 12, 14, and 15) were misfit (p < .05). Item characteristic curves for items 14 and 15 decreased monotonically, implying an inverse relationship between the ability level and the probability of recall. Elimination of the four misfit items provided better fit to the data and met necessary IRT assumptions. Performance on a supraspan list learning test is influenced by multiple cognitive abilities; failure to account for the serial position of words decreases the construct validity of the test as a measure of episodic memory and may provide misleading results. IRT methods can ameliorate these problems and improve construct validity.

The effect of TOMM40 poly-T length on gray matter volume and cognition in middle-aged persons with APOE ε3/ε3 genotype

OBJECTIVE

Apolipoprotein E (APOE) genotypes are associated with variable risk of developing late-onset Alzheimer's disease (LOAD), with APOE epsilon 4 (APOE ε4) having higher risk. A variable poly-T length polymorphism at rs10524523, within intron 6 of the translocase of the outer mitochondrial membrane (TOMM40) gene, has been shown to influence age of onset in LOAD, with very long (VL) poly-T length associated with earlier disease onset, and short poly-T length associated with later onset. In this study, we tested the hypothesis that brain and cognitive changes suggestive of presymptomatic LOAD may be associated with this TOMM40 polymorphism.

METHODS

Among healthy APOE ε3 homozygous adults (N = 117; mean age, 55 years), we compared those who were homozygous for VL/VL (n = 35) TOMM40 poly-T lengths (who were presumably at higher risk) with those homozygous for short (S/S; n = 38) poly-T lengths, as well as those with heterozygous (S/VL; n = 44) poly-T length polymorphisms, on measures of learning and memory and on structural brain imaging.

RESULTS

The VL/VL group showed lower performance than the S/S TOMM40 group on primacy retrieval from a verbal list learning task, a finding which is also seen in early Alzheimer's disease. A dose-dependent increase in the VL TOMM40 polymorphism (from no VL alleles, to S/VL heterozygous, to VL/VL homozygous) was associated with decreasing gray matter volume in the ventral posterior cingulate and medial ventral precuneus, a region of the brain affected early in LOAD.

CONCLUSIONS

These findings among APOE ε3/ε3 late middle-aged adults suggest that a subgroup with VL TOMM40 poly-T lengths may be experiencing incipient LOAD-related cognitive and brain changes.

Cognitive profile of idiopathic normal pressure hydrocephalus

Background/Aims

Frontal lobe dysfunction is believed to be a primary cognitive symptom in idiopathic normal pressure hydrocephalus (iNPH); however, the neuropsychology of this disorder remains to be fully investigated. The objective of this study was to delineate a comprehensive profile of cognitive dysfunction in iNPH and evaluate the effects of cerebrospinal fluid (CSF) shunt surgery on cognitive dysfunction.

Methods

A total of 32 iNPH patients underwent neuropsychological testing of memory, attention, language, executive function, and visuoperceptual and visuospatial abilities. Of these 32 patients, 26 were reevaluated approximately 1 year following CSF shunt surgery. The same battery of tests was performed on 32 patients with Alzheimer's disease (AD) and 30 healthy elderly controls.

Results

The iNPH patients displayed baseline deficits in attention, executive function, memory, and visuoperceptual and visuospatial functions. Impairments of attention, executive function, and visuoperceptual and visuospatial abilities in iNPH patients were more severe than in those with AD, whereas the degree of memory impairment was comparable to that in AD patients. A significant improvement in executive function was observed following shunt surgery.

Conclusion

Patients with iNPH are impaired in various aspects of cognition involving both ‘frontal’ executive functions and ‘posterior cortical’ functions. Shunt treatment can ameliorate executive dysfunction.

Cognition after malignant media infarction and decompressive hemicraniectomy--a retrospective observational study

BACKGROUND

Decompressive hemicraniectomy is a life-saving procedure for patients with malignant middle cerebral artery infarctions. However, the neuropsychological sequelae in such patients have up to now received little attention. In this study we not only describe neuropsychological deficits but also the quality of life and the extent of depression and other psychiatric symptoms in patients after complete media infarction of the non-speech dominant hemisphere.

METHODS

20 patients from two different university hospitals (mean ± standard deviation: 52 ± 14 years of age) who had undergone hemicraniectomy with duraplasty above the non-speech dominant hemisphere at least one year previously were examined using a thorough neurological and neuropsychological work-up. The quality of life and the extent of psychiatric problems were determined on the basis of self-estimation questionnaires. The patients were asked whether they would again opt for the surgical treatment when considering their own outcome. 20 healthy persons matched for age, gender and education served as a control group.

RESULTS

All patients but one were neurologically handicapped, half of them severely. Age was significantly correlated with poorer values on the Rankin scale and Barthel index. All cognitive domain z values were significantly lower than in the control group. Upon re-examination, 18 of 20 patients were found to be cognitively impaired to a degree that fulfilled the formal DSM IV criteria for dementia.

CONCLUSIONS

Patients with non-speech dominant hemispheric infarctions and decompressive hemicraniectomy are at high risk of depression and severe cognitive impairment.

The 10-word learning task in the differential diagnosis of early Alzheimer's disease and elderly depression: A cross-sectional pilot study

OBJECTIVES

Identification of early Alzheimer's disease (AD) has become very important. Episodic memory tasks appear to have predictive power for indicating early AD. Deficits in encoding and storage processes that are characteristic of AD, however, must be distinguished from non-AD deficits that can also affect memory, including difficulties that may be present in depression. This pilot study was set up to ascertain whether a 10-word-list-learning task (delayed recognition and rate of forgetting) may be useful in making the differentiation between mild AD and depression.

METHOD

A Dutch version of Rey's auditory verbal learning test was administered to 36 mild AD patients, 41 depressed patients, and 47 healthy controls. Data were analyzed in a cross-sectional manner.

RESULTS

Receiver operating characteristic analyses showed that for differentiating mild AD and depression, both delayed recognition and percentage of forgetting have sufficient diagnostic accuracy.

CONCLUSION

Percentage of forgetting had the highest diagnostic accuracy for differentiating mild AD and depressed patients and may be useful in the early detection of AD.

Functional MRI study of memory-related brain regions in patients with depressive disorder

BACKGROUND

Structural imaging studies of patients suffering from depressive disorder have revealed reduced hippocampal volume in the majority of cases. The present study aimed specifically at investigating the hippocampal function in unipolar depression using functional magnetic resonance imaging (fMRI).

METHODS

Eleven unipolar depressed patients and eleven healthy control participants matched for age, gender and years of education underwent an associative learning paradigm during fMRI scanning. In the encoding condition of the paradigm, participants had to learn face-profession pairs. These pairs had to be remembered in the retrieval condition.

RESULTS

Hippocampal activity did not differ between depressive patients and control participants during encoding or retrieval. However, during encoding, depressive patients showed increased activity in the left parahippocampal gyrus and decreased activity in frontal and parietal regions. Retrieval of the associative pairs also yielded decreased activation patterns in depressive patients in frontal and parietal areas.

LIMITATIONS

The present findings may be limited by the small sample size of participants. Additionally the comparatively young age of the depressive sample could indicate a comparatively shorter duration of illness, and thereby less salient measurable hippocampal abnormalities.

CONCLUSION

The current study suggests that depression is associated with modified memory-related brain function. In particular the parahippocampal gyrus, the prefrontal cortex and parietal regions show functional alterations during associative learning. These structures as well as their interrelationships may play an important role in the pathogenesis of depressive disorder.

Alzheimer's disease, but not ageing or depression, affects dual-tasking

Two experiments are reported that assess dual task performance in Alzheimer's disease (AD), in chronic depression and in healthy old age. Results suggest that dual task impairments are present in AD but are not shown in depression. This is true even when episodic memory performance is equated between the groups. These results, together with those of previous studies, point to dual task performance as an aid to diagnosis of AD relative to depression. This is of particular relevance when episodic memory tests cannot distinguish between the two conditions. The dual task paradigm appears to have considerable promise in assisting the early detection of the specific cognitive deficits associated with AD, and in monitoring their progression, both in the laboratory setting and in everyday tasks. Results also are of theoretical interest in pointing to a specific dual task coordination function in the healthy human cognitive system that allows for the coordination of two tasks performed simultaneously and which is damaged in AD but not in depression.

Effect of parental family history of Alzheimer's disease on serial position profiles

BACKGROUND

An exaggerated recency effect (ie, disproportionate recall of last-presented items) has been consistently observed in the word list learning of patients with Alzheimer's disease (AD). Our study sought to determine whether there were similar alterations in serial position learning among asymptomatic persons at risk for AD as a result of parental family history.

METHODS

Subjects included 623 asymptomatic middle-aged children of patients with AD (median, 53 years) and 157 control participants whose parents survived to at least age 70 without AD or other memory disorders. All participants were administered the Rey Auditory Verbal Learning Test, which requires learning and recall of 15 unrelated nouns.

RESULTS

There was no significant difference in total words recalled between the AD children and control groups. However, compared with controls, AD children exhibited a significantly greater tendency to recall words from the end (recency) versus beginning (primacy) of the list. Serial position effects were unrelated to apolipoprotein allele epsilon 4 or depressive symptoms.

CONCLUSIONS

Asymptomatic persons at risk for AD by virtue of family history do not show a difference in total words recalled compared with controls, but they exhibit a distinctly different serial position curve, suggesting greater reliance on immediate as opposed to episodic memory. This is the same serial position pattern observed in mild AD, seen here in reduced severity. Longitudinal follow-up is planned to determine whether changes in serial position patterns are a meaningful marker for preclinical detection of AD.

How many items from a word list can Alzheimer's disease patients and normal controls recall? Do they recall in a similar way?

The serial position effect occurs when individuals are asked to recall a list of information that exceeds normal attention span. Alzheimer's disease (AD) patients show lower scores on word span recall tests when compared to healthy aging subjects, younger individuals or depressed patients.

The impact of the CERAD-NP on diagnosis of cognitive deficiencies in late onset depression and Alzheimer's disease

OBJECTIVES

To identify the most appropriate test combination for distinguishing between late onset depression (LOD) and Alzheimer's disease (AD). To achieve this objective, the Consortium to Establish a Register for Alzheimer's Disease-Neuropsychological Battery (CERAD-NP) data of patients diagnosed with these two conditions were analyzed using multiple regression analysis.

METHODS

In the first regression analysis, the following CERAD-NP subtests were included: verbal fluency, Boston naming test, word list learning, constructional praxis, word list recall, and constructional praxis recall. In a second regression analysis, only CERAD-NP memory parameters were included: word list learning, word list recall, word list intrusions, word list savings, word list recognition, word list false positive errors, constructional praxis recall, and constructional praxis savings.

RESULTS

The combination of word list recall and constructional praxis recall best distinguished between LOD and AD, with a ROC of 0.91. In the stepwise regression of memory measures, word list recall, word list savings, and constructional praxis recall was the best combination, resulting in a ROC of 0.92.

CONCLUSION

The most efficacious combination of the CERAD-NP battery for discriminating between LOD and AD consisted of word list recall and constructional praxis recall. Of the CERAD-NP memory measures, word list recall, word list savings, and constructional praxis recall represented the best diagnostic combination.

Étude de la mémoire épisodique dans la sclérose en plaques grâce au California Verbal Learning Test : données en faveur d’une altération de l’encodage

INTRODUCTION

Alteration of episodic memory is one of the main cognitive deficits observed in MS patients.

PATIENTS AND METHODS

We studied episodic memory in a group of 71 MS patients (37 RR, 34 SP) with the California Verbal Learning test (CVLT). Direct scores and calculated indices from CVLT performances were analyzed in comparison with controls.

RESULTS

We observed a deficit of episodic memory in 69 p.cent of patients. This deficit was related to an alteration of encoding and retrieval processes. Despite SP-MS patients performances were constantly lower than those of RR-MS patients no significant difference was observed between the two groups. Significant correlation between the disease duration and CVLT performances were observed for the whole group but not for RR- or SP-MS groups separately, indicating that duration is more important than the phase of the disease in the worsening of memory deficit.

Retention weighted recall improves discrimination of Alzheimer's disease

Impaired recall for early items (primacy) and late items (recency) on word list recall tests are seen in Alzheimer's disease (AD). We compared conventional scoring on the Telephone Instrument for Cognitive Status (TICS) recall list with scorings based on retention-weighted recall (RWR: each item weighted by its serial position) in older adults participating in a community-based aging study. Subjects with mild AD (N=18) did not differ from those without dementia (N=231) with respect to recency (46% vs. 59%, p = 0.2), but had impaired primacy (2% vs. 39%, p < .001) on word recall on the TICS. RWR scoring improved the effect size (1.52 SD) compared to conventional scoring (1.08 SD). With a fixed sensitivity of 85%, specificity was lower using conventional scoring (56%) than RWR (76%) scoring. Our findings suggest that optimized RWR scoring of word list free recall can improve detection of mild AD compared to conventional scoring.

Screening for cognitive impairment: a triage for outpatient care

The current increase in aged individuals in number and proportion of the general population warrants dependable strategies to improve early detection of cognitive impairment. It was the goal of the present study to develop a triage for bedside testing and outpatient services. In a prospective clinical cohort study at the outpatient Memory Clinic, University of Ulm, Germany, 232 subjects were diagnosed with Alzheimer's disease [AD; NINCDS-ADRDA criteria; n = 66; age 65.9 +/- 7.3 years (mean +/- SD); Mini Mental State Examination (MMSE) score 23.4 +/- 4.1], mild cognitive impairment (MCI; criteria of Petersen et al.; n = 48; age 66.4 +/- 7.1 years; MMSE score 28.3 +/- 1.5), and major depressive disorder (DSM-IV criteria; n = 61; age 63.4 +/- 8.0 years; MMSE score 28.6 +/- 1.6). Diagnosis was secured with extensive neuropsychological, clinical, radiological, and laboratory investigations. Six brief screening tests including the Memory Impairment Screen (MIS), Letter Sorting Test (LST), Verbal Fluency (VF), and Clock Drawing Test (CDT) were assessed independently from the diagnostic procedure. We compared single items and composite scores. LST yielded a diagnostic accuracy of 0.81 and 0.62 for AD and MCI patients versus controls, respectively. With the MIS, diagnostic accuracy was 0.89 and 0.71, respectively. With a combination of LST, MIS, VF, and CDT, a sensitivity for AD and MCI patients of 1.00 and 0.83 was achieved. Thus, single-item screening (e.g. LST, VF) taking little more than 1 min and suitable for bedside testing or brief screening in the general practitioner's office yields diagnostic accuracy comparable to standard laboratory tests for other diseases. A composite of screening tests suitable for application in general outpatient care in neurological and psychiatric services reliably detects patients with AD and MCI.

Rey verbal learning test is a useful tool for differential diagnosis in the preclinical phase of Alzheimer's disease: comparison with mild cognitive impairment and normal aging

OBJECTIVE

To confirm that performance in verbal learning and memory test (Rey's Auditory Verbal Learning Test-RAVLT) is a helpful early neuropsychological marker of dementia of Alzheimer's type (DAT).

METHODS

RAVLT was administered as part of a more extensive neuropsychological battery at baseline evaluation in 116 unselected patients referred by subjective memory complaints (SMC). Patients were followed longitudinally for 2 years (average interval of 27.7+/-4 months). Seventy patients were included in the study: 27 developed probable DAT; 17 were diagnosed as cognitively normal persons and 26 were diagnosed with Mild Cognitive Impairment (MCI). Remaining patients abandoned or they did not meet the criteria for DAT, MCI or control. Performance on RAVLT at the baseline evaluation was compared between groups.

RESULTS

Patients diagnosed two years later with probable DAT showed lower results, more frequently performed a score of zero at the delayed recall test (Trial 6) and had a percentage of forgetting (difference between Trials 5 and 6) higher than 75%. Score at delayed recall test and percentage of forgetting correlated with functional scales such as MMSE, Geriatric Depression Screening, Informant Questionnaire and Blessed's Dementia Rating.

CONCLUSIONS

RAVLT could help to identify those patients with SMC who would progress to DAT over a few years, and also to differentiate between the preclinical phase of Alzheimer's disease, mild cognitive impairment and normal aging. A score of zero at the delayed recall test or a percentage of forgetting > or =75% in patients with SMC is suggestive of probable DAT in the future.

Distinct serial position profiles and neuropsychological measures differentiate late life depression from normal aging and Alzheimer's disease

Geriatric depression is associated with cognitive deficits that share similar features with Alzheimer's disease (AD) and normal aging. This study examined cognitive profiles and serial position effects in patients with geriatric depression (N=20) or AD (N=32) and in elderly controls (N=18). Groups were compared on two measures of serial position of the California Verbal Learning Test (CVLT), scaled scores and regional scores. Newly devised regional scores measure the percentage of items recalled as a function of the possible number of items presented from three regions of the list. Regional scores significantly differentiated depressed from control groups, with reduction of recalled items from the middle region. Scaled scores distinguished the depression from the AD groups on primacy and recency regions, with the characteristic recency effect seen in the AD group. Deficits in regional scores of the middle region are discussed in the context of lower resources in depression.

Subjective memory complaints: objective neural markers in patients with Alzheimer's disease and major depressive disorder

Patients with probable Alzheimer's disease and depressive patients frequently present with subjective memory complaints. Objective distinction of underlying neuronal substrate malfunction and early cross-sectional differential diagnosis have been elusive thus far. We used repetitive learning and free recall of abstract geometric patterns during functional magnetic resonance imaging to assess episodic memory in older subjects (ages 56-64 years) who sought first-time medical attention with subjective memory complaints and were diagnosed with probable Alzheimer's disease (NINCDS-ADRDA criteria; ages 51-67 years) or major depressive disorder (DSM-IV; ages 50-65 years). Contrasting healthy seniors or depressive patients with Alzheimer's disease patients revealed superiority of hippocampal activation. Contrasting Alzheimer's disease patients with seniors showed bilateral prefrontal activity as a correlate of futile compensation of episodic memory failure. Contrasting patients who had major depressive disorder with seniors or patients who had Alzheimer's disease showed bilateral activation of the orbitofrontal cortex and the anterior cingulate. Subjective memory complaints may be classified objectively and very early with functional magnetic resonance imaging of episodic memory in groups of patients with Alzheimer's disease and depressive syndrome. This may facilitate drug trials with evaluation of specific treatments, but further studies will be needed to establish the differential diagnosis for the individual patient.

Pathophysiologische und neuropsychologische Aspekte depressiver Störungen

Zusammenfassung: Bei depressiven Störungen sind zahlreiche neurobiologische Auffälligkeiten dokumentiert. Aufschluß darüber geben Untersuchungen bei primärer Depression sowie Untersuchungen bei depressiven Störungen, die sich im Zusammenhang mit Hirnschädigungen, wie etwa Schlaganfällen, manifestieren. Ebenfalls lassen neuropsychologische Befunde Rückschlüsse auf pathophysiologische Mechanismen zu. Vieles deutet darauf hin, daß es bei depressiven Störungen zu einer Störung eines komplexen neuronalen Netzwerkes kommt, insbesondere unter Beteiligung präfrontaler cortikaler Strukturen, der Amygdala und der Basalganglien sowie ihrer monoaminergen Afferenzen aus Hirnstamm und pontinem Tegmentum. Der Befund eines reduzierten Hippokampusvolumens bei Subtypen der Depression geht möglicherweise auf einen Hypercortisolismus zurück. Neurobiologische Auffälligkeiten stellen einen wichtigen Anknüpfungspunkt für antidepressive Therapien dar. Insgesamt ist die Depression als eine psychobiologische Störung konzeptualisierbar, bei der biologische und psychologische Faktoren eng miteinander verzahnt sind.

Der Beitrag der Neuropsychologie zum Problem der Differentialdiagnose Depression versus Demenz

Zusammenfassung: Die Differentialdiagnose Depression versus Demenz ist für den Kliniker eine schwierige und für Betroffene und Angehörige folgenreiche Entscheidung. Viele ältere depressive Patientinnen und Patienten haben kognitive Defizite, die auf den ersten Blick den Symptomen einer beginnenden Demenz ähneln, beispielsweise Beeinträchtigungen mnestischer und exekutiver Funktionen. Diese Beeinträchtigungen sind keineswegs immer reversibel, wie der häufig verwendete, jedoch problematische Begriff “Pseudodemenz” suggeriert. Für die Differentialdiagnose ist ein multidisziplinärer Ansatz erforderlich, der psychopathologische, neurologische, neuroradiologische, labormedizinische und neuropsychologische Befunde integriert. In unserer Übersicht referieren wir Ergebnisse von Metaanalysen, ausgewählte neuere Untersuchungsbefunde und eigene klinischen Erfahrungen im Hinblick auf die Frage, welche kognitiven Funktionen in der neuropsychologischen Diagnostik berücksichtigt werden sollten, um die Validität differentialdiagnostischer Entscheidungen zu verbessern.

Episódio depressivo maior, prevalência e impacto sobre qualidade de vida, sono e cognição em octogenários

OBJETIVOS: Determinar a prevalência de depressão maior em uma população de sujeitos acima de 80 anos residentes na comunidade, comparar os padrões de sono e a função cognitiva entre controles normais e sujeitos com depressão maior e estimar a freqüência de outros transtornos psiquiátricos entre controles e sujeitos deprimidos. MÉTODOS: De uma população de 219 habitantes com mais de 80 anos, residentes em um município semi-rural no sul do Brasil (município de Veranópolis, RS), selecionou-se uma amostra randômica e representativa de 77 sujeitos (35%). Desse grupo, 5 sujeitos que apresentavam critérios de DSM-IV para depressão maior foram comparados com 50 controles sem diagnóstico de demência, delirium ou qualquer transtorno do humor. Os padrões de sono foram avaliados pelo Índice de Pittsburgh de Qualidade do Sono e por um diário do ciclo sono/vigília completado ao longo de duas semanas. Para a avaliação cognitiva, foram usados 5 testes neuropsicológicos: teste de lembranças seletivas de Buschke-Fuld; teste lista de palavras da bateria do CERAD; teste de fluência verbal; e 2 subtestes da bateria de memória de Wechsler. RESULTADOS: A prevalência de depressão maior foi de 7,5%. Sujeitos com esse diagnóstico, quando comparados a sujeitos do grupo-controle, apresentavam mais freqüentemente comorbidade com transtorno de ansiedade generalizada, usavam mais benzodiazepínicos e tinham uma pior qualidade de vida pela escala "Short-form 36". Os idosos deprimidos, quando comparados aos controles, tinham os mesmos padrões de sono e apresentavam o mesmo desempenho nos testes neuropsicológicos. CONCLUSÃO: Os resultados corroboram o conceito de que episódios depressivos são freqüentes entre idosos com mais de 80 anos, causando impacto sobre a qualidade de vida associada à saúde e cursando comorbidade freqüente com transtorno de ansiedade generalizada. Entre os idosos octogenários residentes na comunidade, a depressão maior não aparecia clinicamente sob a forma de "pseudodemência" depressiva e nem tinha impacto sobre os padrões de sono.

Memory and metamemory functioning among depressed patients

Memory and metamemory functioning were studied among 30 adult patients suffering from major depression. The results indicate that, besides showing signs of cognitive slowing, the patients were especially vulnerable to visual memory impairment, whereas verbal, short-term memory, and recall by recognition were more often unaffected. The patients whose depression was characterized by physiological symptoms, such as loss of appetite and sleep disturbances, showed impairment in traditional short-term memory measures, whereas there was no firm connection between cognitive or behavioral depressive symptoms and memory functioning. The depressive patients' generalized view of their memory capability was strongly underestimated, whereas online metamemory accuracy by which one perceives and makes inferences about one's performance was adequate.

Verbal and figural recognition memory: task development and age associations

The goal of the present study was to develop and validate parallel tests of verbal and figural delayed-recognition memory with similar task demands and difficulty levels. Such tasks would allow examination of age differences and longitudinal age changes in visual recognition memory for two types of stimuli, activate divergent neural systems, and allow us to use the same procedures within the confines of functional neuroimaging as those we use in standard neuropsychological administration. The tasks introduced here include a delay between target presentation and test phase, are matched in difficulty, and yield moderate levels of performance. Individual and group differences in task performance were examined in 80 cognitively normal men and women in two older age groups: 60 to 69 and 70 to 85. Accuracy averaged 74% in both tasks, with lower performance in the oldest age group. Although accuracy was equivalent between tasks, subjects had a more liberal response bias in the figural than verbal task. Performance on the new recognition-memory tests was significantly related to Benton Visual Retention Test (BVRT; Benton [1963]. New York: The Psychological Corporation) and California Verbal Learning Test (CVLT; Delis, Kramer, Kaplan, & Ober [1987]. New York: The Psychological Corporation) performance measures. The absence of floor or ceiling effects, wide range of individual variability, and demonstrated concurrent validity of the present tasks suggest their potential utility in functional neuroimaging studies and in the early detection of cognitive decline.

Memory awareness in nursing home residents

BACKGROUND

Health care providers often believe that individuals with cognitive disturbance are unaware of their deficits. The term unawareness was first used to describe hemiplegia following right hemisphere stroke but has since been applied to unawareness of any neurological or neuropsychological deficit. Clinicians usually rely on their subjective observations to evaluate the patient's awareness of deficits, and few investigators have systematically evaluated this important clinical phenomenon.

OBJECTIVE

The aim of this study was to compare cognition, depression, health, and metamemory (capacity, change, locus, and strategy) in four groups of nursing home residents: the cognitively impaired (29%), depressed (18%), mixed with both cognitive impairment and depression (32%), and controls (21%).

METHODS

Subjects were 106 residents of six nursing homes between the ages of 79 and 87 with a mean age of 84.18 (SD = 10.01) years, and an average of six comorbid medical conditions. Cognitive function was measured with the Mini Mental State (MMSE); depression with the Geriatric Depression, and metamemory with the Metamemory in Adulthood scales. Anyone scoring <15 on the MMSE was excluded. Subjects included 31 with cognitive impairment, 19 depressed, 34 mixed, and 22 controls.

RESULTS

In this sample, 61% were cognitively impaired; however, only 12 had a diagnosis in their records indicating cognitive disturbance. Forty-three percent were depressed. The correlations between depression and capacity (r = -0. 38), change (r = -0.50), and locus (r = -0.25) were significant. The controls were significantly younger than the cognitively impaired group. The controls also had higher perceived health status scores than either the cognitively impaired or the depressed group. However, the mixed group's perceived health status scores were significantly higher than the depressed group's scores.

CONCLUSION

The metamemory components of capacity and change were able to differentiate the cognitively impaired from the mixed group. Information on the etiology of cognitive impairment was not available since residents' charts in the six nursing homes provided inadequate documentation and incomplete diagnostic histories. Therefore, quantitative methods for examining memory awareness and the affective state of elderly patients is important for clinicians in order to make informed treatment decisions.

Verbal memory impairment in COPD: its mechanisms and clinical relevance

STUDY OBJECTIVES

Identification of mechanisms accounting for verbal memory impairment in patients with severe COPD; assessing the relationship between verbal memory and the overall cognitive performance; verifying if verbal memory impairment affects medication adherence.

DESIGN

Case-comparison study.

SETTING

Outpatient Departments of Pneumology and Neurology, Day Hospital of General Surgery.

PATIENTS

Forty-two COPD ambulatory patients, age 70+/-9.7 years, with hypoxemia and hypercarbia (group A); 27 normal subjects of comparable age and educational level (group B); 31 patients with Alzheimer's disease (group C); and 26 older normal subjects (group D).

MEASUREMENTS AND RESULTS

The overall cognitive function and verbal memory were evaluated by the Mental Deterioration Battery and 14 indexes of verbal memory. Defective retrieval and recognition mechanisms distinguished group A from group B. According to discriminant analysis, verbal memory profile of COPD patients was group specific in 38.1% of cases and conformed to that of group B, C, and D in 19%, 16.7%, and 26.2% of cases, respectively. In COPD patients, both immediate and delayed recall, the strongest determinants of the discriminant function, were significantly correlated with the overall cognitive performance (rho=0.64, p=0.001; rho=0.61, p=0.001, respectively). Poor adherence to medication regimen was significantly associated with abnormal delayed recall score (82.3% vs 36% in subjects with normal delayed recall, p<0.008).

CONCLUSIONS

Decline of verbal memory parallels that of the overall cognitive function in COPD patients and is due to the impairment of both active recall and passive recognition of learned material. It could be an important determinant of the level of medication adherence.

Depression and memory in the elderly: a meta-analysis

A meta-analysis (N = 40) of the effects of depression on memory in the elderly (sample mean age > or = 55 years) examined variables potentially accounting for divergent findings in the literature. The distribution of effects was bimodal and the effect sizes were heterogeneous. Compared to controls, groups containing unipolar subjects only were significantly less impaired than were mixed unipolar-bipolar; five of six studies mixing depression subtype were associated with the more negative mode. Samples containing younger depressed subjects (< 45 years) were significantly more impaired and were associated with the more negative mode. Significant group differences were found between studies matching their comparison groups reasonably well on years of education and those that did not. Thoroughness of dementia screening yielded no group differences. Although correlated observations precluded significance tests, larger effects were found for (1) figural (vs. verbal) memory; (2) delayed (vs. immediate) memory; and (3) recognition (vs. free recall and incidental or cued recall; incidental and cued recall effects were nearly identical). Similar effects were found for composite memory scores versus constituent and for various presentation paradigms (e.g., single presentation, selective reminding). Effect sizes for these categories were in the moderate range. Difficulties synthesizing this literature are discussed as are suggested remedies and directions for future research.

Differential diagnosis of dementia. The clinical process

Dementia as a syndrome must be differentiated from nondementing conditions. Dementia itself must also be differentiated as to cause, as in certain cases reversible conditions may be responsible. This article examines the clinical process of such differentiation, providing a decision free for diagnosis and a summarizing algorithm for thinking through individual cases, with a focus on the most frequent cause of dementia, Alzheimer's disease. Also outlined are the stages of Alzheimer's disease, with the admonition that variations from the expected progression may represent a dementia diagnosis other than Alzheimer's disease or the co-occurrence of some other contributing factors.