Episodic memory functioning in a community-based sample of old adults with major depression: utilization of cognitive support

Associations between cognitive test scores and pain tolerance: The Tromsø study

OBJECTIVES

Previous studies have suggested that experimental pain sensitivity is associated with cognitive function. The aim of this study is to assess this relationship in a large population-based sample.

METHODS

We included 5,753 participants (aged 40-84 years) from the seventh wave of the population-based Tromsø Study who had been examined with cognitive tests and experimental pain assessments, and for whom information on covariates were available. Cox regression models were fitted using standardized scores on cognitive tests (12-word immediate recall test, digit symbol coding test, and Mini-Mental State Examination [MMS-E]) as the independent variable and cold pressor or cuff pressure pain tolerance as the dependent variables. Statistical adjustment was made for putative confounders, namely, age, sex, education, smoking, exercise, systolic blood pressure, body mass index, symptoms indicating anxiety or depression, analgesic use, and chronic pain.

RESULTS

In multivariate analysis, cold pressor tolerance time was significantly associated with test scores on the 12-word immediate recall test (hazard ratio [HR] 0.93, 95% confidence interval [CI] 0.90-0.97, p < 0.001), the digit symbol coding test (HR 0.94, 95% CI 0.89-0.98, p = 0.004), and the MMS-E (HR 0.93, 95% CI 0.90-0.96 p < 0.001). Tolerance to cuff pressure algometry was significantly associated with 12-word immediate recall (HR 0.94-0.97, p < 0.001) and Digit Symbol Coding test scores (HR 0.93, 95% CI 0.89-0.96, p < 0.001) while there was no significant association with Mini Mental State Examination test score (HR 0.98, 95% CI 0.95-1.00, p = 0.082).

CONCLUSION

Lower pain tolerance was associated with poorer performance on cognitive tests.

Conceptual relatedness promotes memory generalization at the cost of detailed recollection

An adaptive memory system is one that allows us to both retrieve detailed memories as well as generalize knowledge about our past, the latter termed memory generalization and is useful for making inferences about new situations. Research has indicated that memory generalization relies on forming knowledge structures by integrating experiences with shared encountered elements. Whether memory generalization occurs more readily when  experiences also have elements that share established (conceptual) information is less clear. It is also unclear if engaging in memory generalization during learning comes at the cost of retrieving detailed memories, the other function of episodic memory. To address these two knowledge gaps, we paired a modified version of the acquired equivalence task with a recognition memory test. Across three experiments, participants first learned a series of overlapping object-scene pairs (A-X, B-X and A-Y) in which half of the overlapping pairs contained conceptually-related objects (e.g., A-pencil; B-scissors; conceptual condition) and the other half contained unrelated objects (neutral condition). Participants ability to generalize to new overlapping object-scene pairs (B-Y) as well as not-learned but semantically-related objects was measured. Finally, participants completed a recognition memory test that included the encoded objects, perceptually similar lures or new foil objects. Across all experiments, we found higher rates of generalization but reduced detailed memory (indexed by increased false alarms to lure objects) for information learned in the conceptual than neutral condition. These results suggest the presence of conceptual knowledge biases an individual towards a generalization function of memory, which comes at the expense of detailed recollection.

The Entorhinal Cortex and Adult Neurogenesis in Major Depression

Depression is characterized by impairments in adult neurogenesis. Reduced hippocampal function, which is suggestive of neurogenesis impairments, is associated with depression-related phenotypes. As adult neurogenesis operates in an activity-dependent manner, disruption of hippocampal neurogenesis in depression may be a consequence of neural circuitry impairments. In particular, the entorhinal cortex is known to have a regulatory effect on the neural circuitry related to hippocampal function and adult neurogenesis. However, a comprehensive understanding of how disruption of the neural circuitry can lead to neurogenesis impairments in depression remains unclear with respect to the regulatory role of the entorhinal cortex. This review highlights recent findings suggesting neural circuitry-regulated neurogenesis, with a focus on the potential role of the entorhinal cortex in hippocampal neurogenesis in depression-related cognitive and emotional phenotypes. Taken together, these findings may provide a better understanding of the entorhinal cortex-regulated hippocampal neurogenesis model of depression.

Neural Circuitry-Neurogenesis Coupling Model of Depression

Depression is characterized by the disruption of both neural circuitry and neurogenesis. Defects in hippocampal activity and volume, indicative of reduced neurogenesis, are associated with depression-related behaviors in both humans and animals. Neurogenesis in adulthood is considered an activity-dependent process; therefore, hippocampal neurogenesis defects in depression can be a result of defective neural circuitry activity. However, the mechanistic understanding of how defective neural circuitry can induce neurogenesis defects in depression remains unclear. This review highlights the current findings supporting the neural circuitry-regulated neurogenesis, especially focusing on hippocampal neurogenesis regulated by the entorhinal cortex, with regard to memory, pattern separation, and mood. Taken together, these findings may pave the way for future progress in neural circuitry-neurogenesis coupling studies of depression.

Establishing the dose of memory support to improve patient memory for treatment and treatment outcome

BACKGROUND AND OBJECTIVES

Patient memory for the contents of treatment sessions is poor and this is associated with worse treatment outcome. Preliminary findings indicate that treatment provider use of memory support can be helpful in enhancing patient memory for treatment and improving outcome. The development of a novel Memory Support Intervention is currently underway. A key step in this process is to establish the dose of memory support that treatment providers deliver in treatment-as-usual, as well as the optimal dose of memory support needed to maximize patient memory for treatment points and outcomes.

METHODS

Forty-two adults with major depressive disorder (MDD) were randomized to receive either cognitive therapy plus memory support (CS + Memory Support; n = 22) or cognitive therapy as-usual (CT-as-usual; n = 20). Patients completed a free recall of treatment points task at post-treatment. Outcome measures were administered at baseline and post-treatment.

RESULTS

Treatment providers delivering CT-as-usual used, on average, 8.39 instances of memory support and 3.40 different types of memory support per session. Receiver Operating Characteristics (ROC) analyses using the combined sample indicate that 12.45 instances of memory support and 3.88 to 4.13 different types of memory support are needed to maximize patient recall and functional outcome.

LIMITATIONS

Dosing recommendations were established using a limited sample of participants receiving cognitive therapy for MDD.

CONCLUSIONS

Treatment providers appear to deliver a suboptimal amount of memory support. Delivering the optimal dose of memory support could improve treatment outcome.

Everyday discrimination and subsequent cognitive abilities across five domains

OBJECTIVE

Previous research suggests that everyday discrimination is associated with worse concomitant performance in several cognitive domains, as well as faster subsequent declines in episodic memory. This study aimed to extend knowledge on the specificity, durability, and mechanisms of associations between everyday discrimination and cognition by using a comprehensive neuropsychological battery and a longitudinal mediation design.

METHOD

Participants included 3,304 older adults in the Health and Retirement Study Harmonized Cognitive Assessment Protocol. Discrimination was assessed using the Everyday Discrimination Scale. Depressive symptoms were assessed with the 8-item Center for Epidemiological Studies Depression Scale. Vascular diseases were quantified as the self-reported presence of hypertension, diabetes, and heart disease. Confirmatory factor analysis was used to estimate episodic memory, executive functioning, processing speed, language, and visuoconstruction across a battery of 13 neuropsychological tests. Structural equation models controlled for sociodemographics and baseline cognition ascertained 2 to 4 years prior.

RESULTS

Discrimination was associated with more depressive symptoms and vascular diseases. Depressive symptoms mediated negative effects of discrimination on subsequent functioning across all 5 cognitive domains. Vascular diseases additionally mediated negative effects of discrimination on processing speed. After accounting for mediators, direct negative effects of discrimination remained for executive functioning and visuoconstruction.

CONCLUSIONS

This national longitudinal study in the United States provides evidence for broad and enduring effects of everyday discrimination on cognitive aging, which appear to be partially mediated by mental and physical health. Future research should examine additional mechanisms as well as moderators of these associations to better understand points of intervention. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Depressive Symptom Dimensions and Their Association with Hippocampal and Entorhinal Cortex Volumes in Community Dwelling Older Adults

Objective: Research has shown that depression is a risk factor for Alzheimer’s disease (AD) and subsequent cognitive decline. This is compounded by evidence showing an association between depression and reduced hippocampal volumes; a primary structure implicated in the pathogenesis of the disease. Less is known about the relationship between depression and other AD vulnerable regions such as the entorhinal cortex. Given the heterogeneity of depressive symptom presentation, we examined whether symptom dimensions were associated with hippocampal and entorhinal cortex volumes in community dwelling older adults.

Methods: Eighty-one community dwelling adults completed the Beck Depression Inventory – second edition and underwent structural neuroimaging. Measures of hippocampal and entorhinal cortex volumes were obtained using FreeSurfer software. Linear regression models included regions of interest as dependent variables, with depressive symptom dimensions, as independent variables, controlling for total intracranial volumes, age, education, and gender.

Results: Somatic symptoms were negatively associated with total, right, and left hippocampal volumes. Affective symptoms were negatively associated with total entorhinal cortex volumes, with a marginal main effect on left entorhinal cortex volumes.

Conclusion: Our findings provide support for examining depressive symptoms and their association with AD vulnerable regions along subdimensions of affective, cognitive, and somatic symptoms to better understand profiles of symptoms most associated with these regions. Conceptualizing depressive symptoms in this way may also better inform treatment approaches in terms of targeting types of symptoms that may be more closely linked to poorer brain and cognitive health outcomes.

Is episodic memory performance more vulnerable to depressive affect in older adulthood?

This study examined how age, depressive symptoms, demographic variables, frailty, and health factors jointly influence episodic memory across the lifespan in two large, diverse samples. Hierarchical regression analyses from both samples showed that depressive symptoms negatively impacted episodic memory performance with the effect being more pronounced for older adults. Health and frailty tended not to be associated with episodic memory. However, the main effect of depressive symptoms tended to remain significant over and above other predictors, while the interaction with age was weakened with the addition of demographic variables. The unique contribution of this study is demonstrating that the relationship between depressive symptoms and episodic memory is moderated by age across relatively large non-clinical lifespan samples of adults. The findings indicate the importance of measuring and studying depressive symptoms during the course of aging in order to better understand the complex relationship between age, affect, physical functioning, and memory.

Rapid cognitive screening in multiple sclerosis accomplished by the Free Recall and Recognition Test

This study sought to investigate the feasibility of the Free Recall and Recognition Test (FRRT) as a practical screening tool for cognitive impairment in multiple sclerosis (MS). Persons with MS (n =227) were consecutively recruited and assessed with four cognitive tests; FRRT, Symbol Digit Modalities Test (SDMT), Paced Auditory Serial Addition Test (PASAT), and the Mini-Mental State Examination (MMSE). Disease severity was assessed by the Expanded Disability Status Scale (EDSS). The FRRT, which was completed by 99% of the cohort in approximately 5 minutes per assessment, correlated significantly with the other cognitive tests, as well as with the disease severity rating. A cut-off of 4 for the FRRT recall rendered 90% sensitivity and 25% specificity, and a cut-off of 4.2 for the FRRT recognition resulted in 70% sensitivity and 51% specificity. We conclude that the FRRT proved feasible as a practical screening tool for cognitive impairment in MS within a clinical setting. Multiple Sclerosis 2007; 13: 272–274. http://msj.sagepub.com

Depressive Symptomatology and Priming Effects Among Younger and Older Adults

Background/Study Context: This study examined the potential impact of self-reported depressive symptoms on the age-related capacity for inhibition and suppression, utilizing a negative priming paradigm.

METHODS

One hundred eighty-five community-residing adults varying in age (98 younger adults, M_age = 22; 87 older adults, M_age = 69) completed a nonconscious priming task, the Geriatric Depression Scale (GDS), the White Bear Suppression Inventory (WBSI), the Depression Sensitivity Scale (DSS), a free thought suppression task, as well as several measures indexing overall cognitive ability and psychomotor speed. Hierarchical regressions investigated the interaction of depressive symptoms with age and its effect on both positive and negative priming performance, indexing both facilitation and inhibition effects, respectively.

RESULTS

Results support the hypothesis that noncognitive factors affect effortful performance among older adults, although this influence varied with the specific component of the GDS, i.e., Dysphoria, Social Withdrawal, and Cognitive Control, and with the measure of depressive symptoms, i.e., GDS versus DSS.

CONCLUSION

These data suggest that aging's impact on both facilitation and inhibition, e.g., positive and negative priming, are to an extent, a function of individual differences in depressive symptoms that interact with age in influencing the necessity to reallocate one's cognitive resources to deal with depressive thoughts and feelings.

Magnetic Resonance Volumetry: Prediction of Subjective Memory Complaints and Mild Cognitive Impairment, and Associations with Genetic and Cardiovascular Risk Factors

Background/Aims

Subjective memory complaints (SMC) are strong predictors of mild cognitive impairment (MCI) and subsequent Alzheimer's disease. Our aims were to see if fully automated cerebral MR volume measurements could distinguish subjects with SMC and MCI from controls, and if probable parental late-onset Alzheimer's disease (LOAD), apolipoprotein E ε4 genotype, total plasma homocysteine, and cardiovascular risk factors were associated with MR volumetric findings.

Methods

198 stroke-free subjects comprised the control (n = 58), the SMC (n = 25) and the MCI (n = 115) groups. Analysis of covariance and receiver operating characteristic curve was used to see if MR volumetry distinguished subjects with SMC and MCI from controls.

Results

Subjects with SMC and MCI had significantly larger lateral ventricles and smaller hippocampal volumes than controls. The area under the curve in subjects with SMC and MCI compared to that of controls was less than 0.68 for all volumes of intracranial structures. There was an interaction between sex and probable parental LOAD for hippocampal volume, with a significant association between probable parental LOAD and hippocampal volume in women.

Conclusions

Fully automated MR volumetry can distinguish subjects with SMC and MCI from controls in a general population, but insufficiently to assume a clear clinical role. Research on sporadic LOAD might benefit from a sex-specific search for genetic risk factors.

Influence of anxiety symptoms on improvement of neurocognitive functions in patients with major depressive disorder: A 12-week, multicenter, randomized trial of tianeptine versus escitalopram, the CAMPION study

BACKGROUND

Previous research has reported evidence that patients with major depressive disorder (MDD) show anxiety symptoms and neurocognitive impairments. However, the influence of anxiety on neurocognitive function in MDD patients during antidepressant treatment is unclear.

METHOD

MDD patients (n=164) completed a 12-week, multicenter, randomized trial assigned in a 1:1 ratio to either tianeptine or escitalopram. Changes of anxiety symptoms were assessed by the Hamilton Anxiety Rating Scale (HAM-A), and the Hamilton Depression Rating Scale (HAM-D), self-rated subjective cognitive impairment on memory and concentration, the Mini-Mental Status Examination (MMSE), Continuous Performance Test (CPT), Verbal Learning Test (VLT), and Raven's Progressive Matrices (RPM) were assessed every 4 weeks.

RESULTS

During 12 weeks of treatment, decrease in the HAM-A score was significantly associated with improvement of subjective cognitive impairments on memory (p<0.001) and concentration (p<0.001), and objective measures on delayed memory (p=0.006) and reasoning ability (p=0.002), after adjusting for covariates such as baseline HAM-A scores, time, sex, age, education years and assigned medication using the Mixed effects and Generalized Estimated Equation model analysis. However, the other cognitive outcome variables, immediate memory, commission error, and MMSE, which showed significant improvement through 12-week study period, showed no significant association with improvement of anxiety.

CONCLUSION

Improvement of anxiety symptoms was significantly associated with improvement in subjective and objective neurocognitive functions such as delayed memory and reasoning ability in elderly MDD patients during antidepressant treatment, but not significantly associated with improvement of immediate memory and commission error.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT01309776.

Cognitive Rehabilitation with Older Adults

The proportion of older adults seeking rehabilitation services are certain to rise as the population ages. Cognitive rehabilitation techniques can be successfully adapted and used with older adults with a range of clinical diagnoses. An understanding of cognitive changes which could be expected as a result of “normal” (non-disease-related) aging is essential for both assessment and treatment planning for this group. Age-related changes in attention, memory and executive functioning are briefly noted. Common cognitive sequelae of head-injury, depression and dementia are discussed, and useful assessment and rehabilitation strategies described. Case illustrations are used to illustrate major points.

Memory factors in Rey AVLT: Implications for early staging of cognitive decline

Supraspan verbal list learning is widely used to assess dementia and related cognitive disorders where declarative memory deficits are a major clinical sign. While the overall learning rate is important for diagnosis, serial position patterns may give insight into more specific memory processes in patients with cognitive impairment. This study explored these patterns in a memory clinic clientele. One hundred eighty three participants took the Rey Auditory-Verbal Learning Test (RAVLT). The major groups were patients with Alzheimer's disease (AD), Vascular Dementia (VD), Mild Cognitive Impairment (MCI), and Subjective Cognitive Impairment (SCI) as well as healthy controls (HC). Raw scores for the five trials and five serial partitions were factor analysed. Three memory factors were found and interpreted as Primacy, Recency, and Resistance to Interference. AD and MCI patients had impaired scores in all factors. SCI patients were significantly impaired in the Resistance to Interference factor, and in the Recency factor at the first trial. The main conclusion is that serial position data from word list testing reflect specific memory capacities which vary with levels of cognitive impairment.

Interactive effects of KIBRA and CLSTN2 polymorphisms on episodic memory in old-age unipolar depression

The KIBRA (rs17070145) C-allele and the CLSTN2 (rs6439886) T-allele have both been associated with poorer episodic memory performance. Given that episodic memory is affected in depression, we hypothesized that the combination of these risk alleles would be particularly detrimental to episodic memory performance in depressed persons. In the population-based SNAC-K study, 2170 participants (≥ 60 years) without dementia (DSM-IV criteria) and antidepressant pharmacotherapy were clinically examined and diagnosed following ICD-10 criteria for unipolar depression, and genotyped for KIBRA and CLSTN2. Participants were categorized according to unipolar depression status (yes, no) and genotype combinations (KIBRA: CC, any T; CLSTN2: TT, any C). Critically, a three-way interaction effect showed that the CC/TT genotype combination was associated with poorer episodic recall and recognition performance only in depressed elderly persons, with depressed CC/TT carriers consistently performing at the lowest level. This finding supports the view that effects of genetic polymorphisms on cognitive functioning may be most easily disclosed at suboptimal levels of cognitive ability, such as in old-age depression.

Cognitive deficits in unipolar old-age depression: a population-based study

BACKGROUND

There is substantial variability in the degree of cognitive impairment among older depressed persons. Inconsistencies in previous findings may be due to differences in clinical and demographic characteristics across study samples. We assessed the influence of unipolar depression and severity of depression on cognitive performance in a population-based sample of elderly persons aged ⩾60 years.

METHOD

Eighty-nine persons fulfilled ICD-10 criteria for unipolar depression (mild, n = 48; moderate, n = 38; severe, n = 3) after thorough screening for dementia (DSM-IV criteria), psychiatric co-morbidities and antidepressant pharmacotherapy. Participants (n = 2486) were administered an extensive cognitive test battery.

RESULTS

Moderate/severe unipolar depression was associated with poorer performance on tasks assessing processing speed, attention, executive function, verbal fluency, episodic memory and vocabulary. Mild depression was associated with poorer performance in processing speed, and few differences between mild and moderate/severe depression were observed. No association between depression and short-term memory, general knowledge or spatial ability was observed. Increasing age did not exacerbate the depression-related cognitive deficits, and the deficits remained largely unchanged after excluding persons in a preclinical phase of dementia. Furthermore, depression-related cognitive deficits were not associated with other pharmacological treatments that may affect cognitive performance.

CONCLUSIONS

Cognitive deficits in unipolar old-age depression involve a range of domains and the cognitive deficits seem to follow the spectrum of depression severity. The finding that mild depression was also associated with poorer cognitive functioning underscores the importance of detecting mild depression in elderly persons.

Mild cognitive impairment, risk factors and magnetic resonance volumetry: role of probable Alzheimer's disease in the family

BACKGROUND/AIMS

Late-onset Alzheimer's disease (LOAD) comprises sporadic LOAD and familial LOAD. We wanted to determine whether total plasma homocysteine (Hcy), cardiovascular risk factors and volumetric analyses of cerebral magnetic resonance imaging (MRI) were differently associated with mild cognitive impairment (MCI) in subjects from families with aggregation of LOAD (probable familial LOAD) and MCI in subjects from families without LOAD (probable sporadic LOAD).

METHODS

A total of 103 subjects with MCI without known stroke or other apparent causative diseases were included as cases together with 58 controls. The cases were stratified into 3 groups according to the number of biological relatives with probable LOAD on one side of the family. Cerebral MRI was obtained from all. The case groups were compared to the control group in sex-specific analyses of covariance.

RESULTS

Hcy was significantly elevated in all cases compared to controls, except for women with probable familial LOAD. These women also had significantly smaller hippocampal volume and significantly larger lateral ventricles, unlike the women in the other case groups.

CONCLUSIONS

Our findings suggest that research on Hcy, cardiovascular risk factors and other potential risk factors for LOAD might benefit from distinguishing between sporadic and familial LOAD.

Improving Outcome of Psychosocial Treatments by Enhancing Memory and Learning

Mental disorders are prevalent and can lead to significant impairment. Some progress has been made toward establishing treatments; however, effect sizes are small to moderate, gains may not persist, and many patients derive no benefit. Our goal is to highlight the potential for empirically supported psychosocial treatments to be improved by incorporating insights from cognitive psychology and research on education. Our central question is: If it were possible to improve memory for the content of sessions of psychosocial treatments, would outcome substantially improve? We leverage insights from scientific knowledge on learning and memory to derive strategies for transdiagnostic and transtreatment cognitive support interventions. These strategies can be applied within and between sessions and to interventions delivered via computer, the Internet, and text message. Additional novel pathways to improving memory include improving sleep, engaging in exercise, and using imagery. Given that memory processes change across the lifespan, services to children and older adults may benefit from different types and amounts of cognitive support.

Abnormalities of autobiographical memory of patients with depressive disorders: a meta-analysis

BACKGROUND

Previous studies on the autobiographical memory (AM) of depressed patients had inconsistent findings. Various severities of depression in patients in these studies may lead to conflicting results. However, the differences in the procedure of the autobiographical memory tests (AMTs) may also influence the AM results.

OBJECTIVE

In this study, we analyse the results published so far to research the AM characteristics of patients with depressive disorders and identify moderators that affect the assessment results while using AMT in this field.

METHOD

A systematic search was conducted using following databases: MEDLINE, PubMed, ScienceDirect, Cnki, and Google Scholar, yielding 22 studies of patients with depressive disorders and autobiographical memory published between 1986 and 2010.

RESULTS

The results of meta-analysis showed that, compared with the control group, the patients with depressive disorders reported less specific AMs (g = -1.051) and more overgeneralized AMs (g = 1.115). The patients with depressive disorders also recalled more slowly (g = 0.400). The effect sizes of overgeneral memory could be predicted by the self-reported depression score of the depressed patients (B = -.329, p < .01). The mean effect sizes of AMT indices were affected by the AMT characteristics (i.e., number of cue word, max response time, prompting, presentation of cue word, taping, and so on).

CONCLUSIONS

Our results suggest that overgeneralization and response lag are the AM deficits in patients with depressive disorders. The parameters of AMT are important factors, which are related to the inconsistency in the assessment of AM in patients with depressive disorders. Some recommendations on AMT and programme research design are given for future research.

Albuminuria and carotid atherosclerosis as predictors of cognitive function in a general population

BACKGROUND/AIMS

Albuminuria and carotid atherosclerosis are predictors of cardiovascular disease and potential predictors of cognitive decline. Our aim was to study whether albuminuria was an early predictor of cognitive function independent of carotid atherosclerosis in a general population.

METHODS

The study population comprised 1,577 adults without self-reported stroke. In 1994 and 2007 all were screened for cardiovascular risk factors, urinary albumin-creatinine ratio (ACR), carotid intima-media thickness and carotid total plaque area (TPA). Endpoints were neuropsychological test results in 2007 from the digit symbol test, the finger-tapping test, the Mini Mental Status Examination and the 12-word test parts 1 and 2. Multivariate linear regression was used to assess associations.

RESULTS

Higher ACR, ΔACR, intima-media thickness, TPA and ΔTPA independently predicted a lower score on the digit symbol test. Higher ΔACR and ΔTPA predicted a lower score on the finger-tapping test. Higher TPA predicted a lower score on the 12-word test part 1 (immediate recall). Smoking predicted lower scores on the digit symbol and finger-tapping tests independent of albuminuria and carotid atherosclerosis.

CONCLUSIONS

Our results suggest that albuminuria, carotid atherosclerosis and smoking are independent predictors of executive function and motor tempo.

The effect of age on fluid intelligence is fully mediated by physical health

The present study investigated the extent to which the effect of age on cognitive ability is predicted by individual differences in physical health. The sample consisted of 118 volunteer subjects who were healthy and ranging in age from 26 to 91. The examinations included a clinical investigation, magnetic resonance imaging (MRI) brain neuroimaging, and a comprehensive neuropsychological assessment. The effect of age on fluid IQ with and without visual spatial praxis and on crystallized IQ was tested whether being fully-, partially- or non-mediated by physical health. Structural equation analyses showed that the best and most parsimonious fit to the data was provided by models that were fully mediated for fluid IQ without praxis, non-mediated for crystallized IQ and partially mediated for fluid IQ with praxis. The diseases of the circulatory and nervous systems were the major mediators. It was concluded from the pattern of findings that the effect of age on fluid intelligence is fully mediated by physical health, while crystallized intelligence is non-mediated and visual spatial praxis is partially mediated, influenced mainly by direct effects of age. Our findings imply that improving health by acting against the common age-related circulatory- and nervous system diseases and risk factors will oppose the decline in fluid intelligence with age.

Neural changes underlying the development of episodic memory during middle childhood

Episodic memory is central to the human experience. In typically developing children, episodic memory improves rapidly during middle childhood. While the developmental cognitive neuroscience of episodic memory remains largely uncharted, recent research has begun to provide important insights. It has long been assumed that hippocampus-dependent binding mechanisms are in place by early childhood, and that improvements in episodic memory observed during middle childhood result from the protracted development of the prefrontal cortex. We revisit the notion that binding mechanisms are age-invariant, and propose that changes in the hippocampus and its projections to cortical regions also contribute to the development of episodic memory. We further review the role of developmental changes in lateral prefrontal and parietal cortices in this development. Finally, we discuss changes in white matter tracts connecting brain regions that are critical for episodic memory. Overall, we argue that changes in episodic memory emerge from the concerted effort of a network of relevant brain structures.

Carotid artery plaque progression and cognitive decline: the Tromsø Study 1994-2008

BACKGROUND

Carotid atherosclerosis is a risk factor for stroke and cognitive decline, but knowledge on how progression of carotid atherosclerosis affects cognitive function in stroke-free individuals is scarce.

METHODS

In the population-based Tromsø study, we calculated the change in ultrasound-assessed carotid plaque number and total plaque area from baseline (survey 4) to follow-up 7 years later (survey 5) in 4274 middle-aged stroke-free subjects. Cognitive function was assessed at follow-up by the verbal memory test, the digit-symbol coding test, and the tapping test and repeated after an additional 6 years in a subgroup of 2042 subjects (survey 6). Associations between the average of survey 4 and survey 5 plaque scores and the progression of plaque scores and cognitive test scores were assessed in regression analyses adjusted for baseline age, sex, education, depression, and cardiovascular risk factors.

RESULTS

Progression of total plaque area was associated with lower scores in the digit-symbol coding test (multivariable adjusted standardized β, -0.03; 95% CI, -0.05 to -0.00; P = 0.04) and the tapping test (β, -0.03; 95% CI, -0.06 to -0.00; P = 0.03). Similar results were seen for progression of plaque number. The average plaque scores were associated with lower scores in all cognitive tests (P-values ≤ 0.01). No association was found between plaque scores and cognitive decline.

CONCLUSIONS

The average plaque scores were associated with lower scores in all cognitive tests. Progression of plaque scores was associated with lower scores in the digit-symbol coding test and the tapping test, but not with the verbal memory test or with cognitive decline.

Preclinical cognitive trajectories differ for Alzheimer's disease and vascular dementia

We investigated differences between Alzheimer's disease (AD) and vascular dementia (VaD) from the appearance of the first cognitive symptoms, focusing on both time of onset and rate of accelerated decline for different cognitive functions before dementia diagnosis. Data from a longitudinal population-based study were used, including 914 participants (mean age = 82.0 years, SD = 5.0) tested with a cognitive battery (word recall and recognition, Block Design, category fluency, clock reading) on up to four occasions spanning 10 years. We fit a series of linear mixed effects models with a change point to the cognitive data, contrasting each dementia group to a control group. Significant age-related decline was observed for all five cognitive tasks. Relative to time of diagnosis, the preclinical AD persons deviated from the normal aging curve earlier (up to 9 years) compared to the preclinical VaD persons (up to 6 years). However, once the preclinical VaD persons started to decline, they deteriorated at a faster rate than the preclinical AD persons. The results have important implications for identifying the two dementia disorders at an early stage and for selecting cognitive tasks to evaluate treatment effects for persons at risk of developing AD and VaD.

Carotid atherosclerosis predicts lower cognitive test results: a 7-year follow-up study of 4,371 stroke-free subjects - the Tromsø study

BACKGROUND

Carotid artery atherosclerosis is a major risk factor for stroke and subsequent cognitive impairment. Prospective population studies have shown associations between carotid intima-media thickness (IMT) and stenosis and cognitive decline and dementia in elderly stroke-free persons, whereas results in the middle-aged are conflicting.

METHODS

In this prospective population-based study, 4,371 stroke-free middle-aged participants underwent carotid ultrasound examination and assessment of vascular risk factors at baseline and were tested for cognitive function 7 years later. Associations between IMT, number of plaques and total plaque area and cognitive test scores on verbal memory test, digit symbol-coding test and tapping test were assessed in linear regression models.

RESULTS

In the multivariable analyses adjusted for sex, age, education, depression and vascular risk factors, the presence of plaques was significantly associated with lower test scores on the verbal memory test (p = 0.01) and on the digit symbol-coding test (p = 0.03). The number of plaques (p = 0.01) and the total plaque area (p = 0.02) were associated with lower scores on the verbal memory test. No significant association was seen between common carotid artery IMT and cognitive test scores. The tapping test was not associated with the carotid ultrasound variables.

CONCLUSIONS

In this middle-aged general population, subclinical carotid atherosclerosis measured as the presence of plaques, number of plaques and total plaque area were independent long-term predictors of lower cognitive test scores.

Clinical features and multidisciplinary approaches to dementia care

Dementia is a clinical syndrome of widespread progressive deterioration of cognitive abilities and normal daily functioning. These cognitive and behavioral impairments pose considerable challenges to individuals with dementia, along with their family members and caregivers. Four primary dementia classifications have been defined according to clinical and research criteria: 1) Alzheimer's disease; 2) vascular dementias; 3) frontotemporal dementias; and 4) dementia with Lewy bodies/Parkinson's disease dementia. The cumulative efforts of multidisciplinary healthcare teams have advanced our understanding of dementia beyond basic descriptions, towards a more complete elucidation of risk factors, clinical symptoms, and neuropathological correlates. The characterization of disease subtypes has facilitated targeted management strategies, advanced treatments, and symptomatic care for individuals affected by dementia. This review briefly summarizes the current state of knowledge and directions of dementia research and clinical practice. We provide a description of the risk factors, clinical presentation, and differential diagnosis of dementia. A summary of multidisciplinary team approaches to dementia care is outlined, including management strategies for the treatment of cognitive impairments, functional deficits, and behavioral and psychological symptoms of dementia. The needs of individuals with dementia are extensive, often requiring care beyond traditional bounds of medical practice, including pharmacologic and non-pharmacologic management interventions. Finally, advanced research on the early prodromal phase of dementia is reviewed, with a focus on change-point models, trajectories of cognitive change, and threshold models of pathological burden. Future research goals are outlined, with a call to action for social policy initiatives that promote preventive lifestyle behaviors, and healthcare programs that will support the growing number of individuals affected by dementia.

Effects of intensified metabolic control on CNS function in type 2 diabetes

The mild cognitive decline associated with type 2 diabetes (T2DM) has been suggested to be reversible with improved glycemic control. In order to characterise this cognitive decline and study the effects of improved glycemic control we have studied patients with T2DM (N=28) and healthy control subjects (N=21). One group of patients with diabetes (N=15) were given a 2-month treatment of intensified glycemic control, whereas the other group (N=13) maintained their regular treatment. Cognitive function in four different domains, auditory event-related potentials (ERPs) and resting EEG power spectrum were studied in the two groups of patients and in healthy control subjects before and after the 2-month trial period. There were significant differences at baseline (p<0.02) between patients with T2DM and controls. Patients had lower scores in two cognitive domains: verbal fluency (p<0.01) and visuospatial ability (p<0.03). T2DM also affected ERP with a decrease in N100 amplitude (p<0.04) and an increase in P300 latency (p<0.03). Furthermore, resting EEG activity in the beta band (13-30Hz) was reduced (p<0.04). The change between 1st and 2nd investigation was significantly different in the three groups of patients/subjects (p<0.03). Patients receiving intensified treatment for glycemic control had an improvement of cognitive ability in visuospatial ability (p<0.02) and semantic memory performance (p<0.04) together with increased resting EEG activity in the alpha band (8-13Hz, p<0.02) and connectivity in the theta (4-8Hz, p<0.03) and alpha bands (p<0.03) over central and lateral regions. Furthermore, there was an increase in the connectivity in the beta band (p<0.04) over the central regions of the scalp. In conclusion, subjects with T2DM had a similar type of cognitive function impairment and EEG/ERP abnormality as previously demonstrated for subjects with type 1 diabetes (T1DM). Intensified therapy showed cognitive improvement not shown for regular treatment, suggesting that the negative effect of T2DM on cognition is reversible by means of improved glycemic control. Furthermore, there was an improvement in electro-physiological measures, suggesting increased availability of compensatory mechanisms in subjects with intensified treatment.

Onset and rate of cognitive change before dementia diagnosis: findings from two Swedish population-based longitudinal studies

We used data from two population-based longitudinal studies to estimate time of onset and rate of accelerated decline across cognitive domains before dementia diagnosis. The H70 includes an age-homogeneous sample (127 cases and 255 non-cases) initially assessed at age 70 with 12 follow-ups over 30 years. The Kungsholmen Project (KP) includes an age-heterogeneous sample (279 cases and 562 non-cases), with an average age of 82 years at initial assessment, and 4 follow-ups spanning 13 years. We fit mixed linear models to the data and determined placement of change points by a profile likelihood method. Results demonstrated onset of accelerated decline for fluid (speed, memory) versus crystallized (verbal, clock reading) abilities occurring approximately 10 and 5 years before diagnosis, respectively. Although decline before change points was greater for fluid abilities, acceleration was more pronounced for crystallized abilities after the change points. This suggests that onset and rate of acceleration vary systematically along the fluid-crystallized ability continuum. There is early onset in fluid abilities, but these changes are difficult to detect due to substantial age-related decline. Onset occurred later and acceleration was greater in crystallized abilities, suggesting that those markers may provide more valid identification of cases in later stages of the prodromal phase.

Impact of cardiovascular risk factors on cognitive function: the Tromsø study

BACKGROUND AND PURPOSE

The role of cardiovascular risk factors in the pathogenesis of cognitive impairment and dementia remains still unclear. We examined the impact of cardiovascular risk factors on cognitive function in a large longitudinal population study.

METHODS

Subjects were 5033 stroke-free men and women who participated in a longitudinal population-based study. Cardiovascular risk factors were measured at baseline, and cognitive function was assessed after 7 years of follow-up with verbal memory test, digit-symbol coding test, and tapping test.

RESULTS

Diabetes, systolic blood pressure, and current smoking were independently associated with lower cognitive test results in men and women. Low physical activity was independently associated with lower scores in women. We found no consistent association between total-cholesterol, HDL-cholesterol, coronary heart disease or BMI, and cognitive test results.

CONCLUSIONS

Diabetes, smoking, hypertension, and low physical activity were associated with lower cognitive test results. The study suggests that these modifiable risk factors should be emphasized in the prevention of cognitive decline.

Differential levels of apolipoprotein E and butyrylcholinesterase show strong association with pathological signs of Alzheimer's disease in the brain in vivo

Recently, we reported that 3 of the known risk factors of Alzheimer's disease (AD), i.e., advanced age, apolipoprotein E (ApoE) ε4, and female gender, are associated with differential levels of ApoE proteins and butyrylcholinesterase (BuChE) in the cerebrospinal fluid (CSF) of AD patients. The ApoE ε4 allele and certain BuChE polymorphisms synergistically affect the conversion rate of mild cognitive impairment (MCI) to AD. Here, we investigated interrelationships between ApoE and BuChE levels, and pathological markers of AD in vivo. CSF from patients with probable AD, assessed for cerebral glucose metabolism (CMRglc; n = 50) and Pittsburgh compound B (PIB) retention (β-amyloid [Aβ] load, n = 29) by positron emission tomography (PET), was used for measurement of BuChE, ApoE, Aβ, tau, phosphorylated tau (P-tau) and interleukin-1β (IL-1β) levels. Levels of ApoE and BuChE strongly correlated with CMRglc (fluorodeoxyglucose [FDG]-PET, r = 0.54, p < 0.0001, n = 50), cerebral Aβ load (PIB retention, r = 0.73, p < 0.0001, n = 29), and CSF P-tau (r = 0.73, p < 0.0001, n = 33). High ApoE protein was tied to low CMRglc and high PIB retention and P-tau. BuChE levels had opposite relationships. Other CSF covariates were levels of interleukin-1β and Aβ(42) peptide. The pattern of the patients' cognitive Z-scores strongly supported these observations. High ApoE protein was also linked to changes in 3 of the biodynamic properties of BuChE. In vitro analysis indicated that high ApoE protein levels were related to an increased pool of dormant BuChE molecules with an abnormally high intrinsic catalytic rate in CSF, which was "turned on" by excess Aβ peptides. The findings suggest that abnormally high levels of ApoE may play a causative role in the pathological events of AD, particularly those involving the early cholinergic deficit in the AD brain, through modulation of cholinesterases activities, hence disturbing the acetylcholine-dependent activity of neurons and nonexcitable cells such as glial cells.

Episodic memory and organizational strategy in free recall in unipolar depression: the role of cognitive support and executive functions

Executive functioning and memory impairment have been demonstrated in adults with depression. Executive functions and memory are related, mainly when the memory tasks require controlled processes (attentional resource demanding processes)--that is, when a low cognitive support (external aid) is provided. A cross-sectional study was carried out on 45 participants: 21 with depression, and 24 healthy controls matched for age, verbal ability, education level, and anxiety score. Cognitive support was manipulated by providing a categorized word list at encoding, presented either clustered (high cognitive support) or randomized (low cognitive support) to both depressed and healthy adults. The number of words recalled was calculated, and an index of clustering was computed to assess organizational strategies. Participants were also administered cognitive tests (executive functions, cognitive speed, and categorical fluency) to explore the mediators of organizational strategies. Depressed participants had greater difficulty recalling and organizing the words, but the differences between the two groups were reduced for both measures when high cognitive support was provided at encoding. Healthy adults performed better on all cognitive tests. Statistical analyses revealed that in the depressed group, executive functions were the only variable associated with clustering and only when low cognitive support was provided. These findings support the view that the decrement in executive function due to depression may lead to impairment in organization when this mnemonic strategy has to be self-initiated.

Increasing CSF phospho-tau levels during cognitive decline and progression to dementia

BACKGROUND

Little is known about longitudinal changes of cerebrospinal fluid (CSF) biomarkers during cognitive decline in neurodegenerative disease progression.

OBJECTIVE

To investigate longitudinal changes in CSF biomarkers--total-tau (T-tau), phospho-tau (P-tau) and beta-amyloid (Abeta42)--during cognitive decline.

METHODS

Forty memory clinic patients (47.5% females), aged 61.3+/-7.6 (S.D.) years, non-demented at baseline, underwent lumbar puncture and neuropsychological testing at two occasions. Baseline mean MMSE-score was 28.3+/-1.8. Patients were divided into three groups based on baseline memory functioning; severely impaired (SIM), moderately impaired (MIM) and no impairment (NIM).

RESULTS

There was a significant increase in P-tau in the SIM-group during follow-up, while P-tau in MIM and NIM did not change. Eighty-three percent of the SIM-patients converted to dementia (80% AD), while most MIM- and NIM-patients remained non-demented. T-tau- and Abeta42-levels did not change in any of the memory groups during follow-up.

CONCLUSION

Increasing P-tau levels during cognitive decline and conversion to dementia suggest that P-tau may be useful as a longitudinal marker of the neurodegenerative process.

PET imaging of the in vivo brain acetylcholinesterase activity and nicotine binding in galantamine-treated patients with AD

The effect of galantamine treatment on cortical acetylcholinesterase (AChE) activity and nicotinic receptor binding was investigated by positron emission tomography (PET) in 18 patients with mild Alzheimer's disease (AD) in relation to galantamine concentration and the patients' cognitive performances. The first 3 months of the study was of a randomized double-blind placebo-controlled design, during which 12 patients received galantamine (16-24mg/day) and 6 patients the placebo, and this was followed by 9 months' galantamine treatment in all patients. The patients underwent PET examinations to measure cortical AChE activity ((11)C-PMP) and (11)C-nicotine binding. Neuropsychological tests were performed throughout the study. Inhibition (30-40%) of cortical AChE activity was observed after 3 weeks to 12 months of galantamine treatment. No significant change in mean cortical (11)C-nicotine binding was observed during the study. (11)C-Nicotine binding, however, positively correlated with plasma galantamine concentration. Both the changes of AChE activity and (11)C-nicotine binding correlated positively with the results of a cognitive test of attention. In conclusion, galantamine caused sustained AChE inhibition for up to 12 months. At the individual level, the in vivo cortical AChE inhibition and (11)C-nicotine binding were associated with changes in the attention domain of cognition rather than episodic memory.

Early symptoms and signs of cognitive deficits might not always be detectable in persons who develop Alzheimer's disease

OBJECTIVE

Clinical syndromes such as amnestic mild cognitive impairment (MCI) are highly predictive of future development of Alzheimer's disease (AD), but it is not known how many of the individuals that develop the disease can be identified with these syndromes. This study aims to determine how many individuals with AD show detectable symptoms or clinical signs of cognitive deficits three years before diagnosis.

METHODS

152 incident AD cases were identified in a dementia-free cohort of 1417 persons aged 75-95, after three-year follow-up from a prospective population-based study, the Kungsholmen Project. Symptoms of cognitive impairment including the subjective report of memory problems, and cognitive deficits were objectively measured with an extensive neuropsychological test battery at baseline. Incident AD was clinically diagnosed according to DSM-IIIR criteria at three-year follow-up.

RESULTS

Only half of future AD cases reported subjective memory problems three years before diagnosis. More than one-third of incident AD cases did not exhibit detectable deficits in any of the investigated specific cognitive domains. Only 38.3% had both subjective complaints and domain-specific cognitive deficits.

CONCLUSIONS

Symptoms and signs currently used to define MCI are not always present in persons who develop AD. Increasing the number of potentially identifiable and treatable preclinical AD cases is unfeasible unless more sensitive subjective and objective markers are identified. Furthermore, as only half of future AD cases report subjective memory problems three years before diagnosis, the number of persons coming to the attention of medical care is limited.

Differential effects of depressive symptoms on prospective and retrospective memory in old age

The effects of depressive symptoms on prospective and retrospective memory were examined in a population-based sample of elderly persons (n = 404). Depression was assessed using the Comprehensive Psychopathological Rating Scale and treated as a continuous variable. The variation in depressive symptoms ranged from no symptoms to presence of a clinical depression. Depressive symptoms had a negative effect on consolidation and retrieval in retrospective memory. However, the retrospective, but not the prospective, component of prospective memory was affected by depression. The findings are discussed in light of medial-temporal lobe alterations in depression.

Longitudinal trajectories of cognitive change in preclinical Alzheimer's disease: a growth mixture modeling analysis

Preclinical Alzheimer's disease (AD) refers to a period of time prior to diagnosis during which cognitive deficits among individuals who will go on to receive a diagnosis of AD are present. There is great interest in describing the nature of cognitive change during the preclinical period, in terms of whether persons decline in a linear fashion to diagnosis, or exhibit some stability of functioning, followed by rapid losses in performance. In the current study we apply Growth Mixture Modeling to data from The Kungsholmen Project to evaluate whether decline in Mini Mental State Examination (MMSE) scores during the preclinical period of AD follows a linear or quadratic function. At the end of a 7-year follow-up period, some individuals would be diagnosed with AD (n=71), whereas others would remain free of dementia (n=457). The results indicated that a two-group quadratic model of decline provided the best statistical fit measures, as well as the greatest estimates of sensitivity (67%) and specificity (86%). Differences in MMSE scores were apparent at baseline, but the preclinical AD group began to experience precipitous declines three years prior to diagnosis. Finally, persons who were misclassified as preclinical AD had fewer years of education and poorer MMSE scores at baseline.

Imaging markers of mild cognitive impairment: Multivariate analysis of CBF SPECT

This study aimed to investigate cross-sectional and longitudinal changes of regional cerebral blood flow (rCBF) in preclinical dementia using single photon emission computed tomography (SPECT). SPECT and cognitive function were investigated in 39 mild cognitive impairment (MCI) subjects and 20 age-matched controls. All subjects were followed longitudinally 19 months on average, 16 MCI subjects progressed to Alzheimer's disease (AD), who were retrospectively defined as progressive mild cognitive impairment (PMCI) at baseline and 23 MCI subjects remained stable and were defined as stable mild cognitive impairment (SMCI) at baseline. SPECT was performed both at the initial investigation and at follow-up. Image data were analyzed using multivariate analysis, SPM and volume of interest (VOI)-based analysis. Significant covariate patterns were derived, which differentiate among PMCI, SMCI and controls at baseline as well as describe the longitudinal progression of PMCI. The combined SPECT and neuropsychology increased the diagnostic accuracy of PMCI at baseline. SPECT and neuropsychological testing can be used objectively for both baseline diagnosis and to monitor changes in brain function during very early AD.

Changes in brain 11C-nicotine binding sites in patients with mild Alzheimer's disease following rivastigmine treatment as assessed by PET

RATIONALE

Marked reduction in the cortical nicotinic acetylcholine receptors is observed in the brain of patients suffering from Alzheimer's disease (AD). Although cholinesterase inhibitors are used for symptomatic treatment of mild to moderate AD patients, numerous long-term treatment studies indicate that they might stabilize or halt the progression of the disease by restoring the central cholinergic neurotransmission. Thus, we used positron emission tomography (PET) technique as a sensitive approach to assess longitudinal changes in the nicotine binding sites in the brains of patients with AD.

OBJECTIVE

To evaluate changes in brain nicotinic binding sites in relation to inhibition level of cholinesterases in cerebrospinal fluid (CSF) and plasma and changes in cognitive performance of the patients in different neuropsychological tests after rivastigmine treatment.

MATERIALS AND METHODS

Ten mild AD patients received rivastigmine for 12 months. A dual-tracer PET model with administration of (15)O-water and (S)(-)(11)C-nicotine was used to assess (11)C-nicotine binding sites in the brain at baseline and after 3 and 12 months of the treatment. Cholinesterase activities in CSF and plasma were assessed colorimetrically.

RESULTS

The (11)C-nicotine binding sites were significantly increased 12-19% in several cortical brain regions after 3 months compared with baseline, while the increase was not significant after 12 months of the treatment. After 3 months treatment, low enzyme inhibition in CSF and plasma was correlated with higher cortical (11)C-nicotine binding. The (11)C-nicotine binding positively correlated with attentional task at the 12-month follow-up.

CONCLUSION

Changes in the (11)C-nicotine binding during rivastigmine treatment might represent remodeling of the cholinergic and related neuronal network.

The importance of impaired physical health and age in normal cognitive aging

The objective of this study was to investigate the importance of impaired physical health and age in normal cognitive aging. In our cross-sectional, clinical and explorative study, medical and neuropsychological data from 118 voluntary healthy controls aged 26-91 years were collected from five recruitment occasions. Health was assessed according to a criterion reflecting clinical and subclinical severity. The examinations included a clinical investigation, brain neuroimaging, and a comprehensive neuropsychological assessment. Regression analyses showed a significant incidence of clinical and subclinical medical disorders that explained 10.8% of the variation in cognitive performance, while age-related impairment explained 5.6%. Findings of the central nervous system were important but various other medical findings explained about half of the health-related variation. Cognitively demanding tasks were more susceptible to impaired physical health while tasks comprising salient motor- and visual spatial elements were more prone to be impaired by age. Our findings suggest (1) that impaired physical health is more important than chronological age in accounting for cognitive impairment across the adult lifespan, (2) that age and health dissociate with regard to cognitive functions affected, and (3) that selection for so-called "super healthy" elderly people might be justified in cognitive research. Because the prevalent diseases in normal aging are potentially preventable, the present findings promise good prospect for prevention of future cognitive disability among elderly people.

A population-based study of depressive symptoms in multiple sclerosis in Stockholm county: association with functioning and sense of coherence

OBJECTIVES

To explore and analyse the prevalence of depressive symptoms in people with multiple sclerosis (PwMS), taking into account disease-related and sociodemographic factors, and also to analyse the association between depressive symptoms and functioning (tested and self-reported) and sense of coherence (SOC), respectively.

METHODS

Home visits were made to a population-based sample of 166 PwMS. Data were obtained from structured, face-to-face interviews using the Beck Depression Inventory (BDI), the Sickness Impact Profile (SIP) and the SOC scale. A range of tests were also carried out for analyses of different aspects of functioning such as cognitive function, walking capacity and manual dexterity, and structured interviews examined activities of daily living and frequency of social/lifestyle activities.

RESULTS

19% (28/149) of the people were depressed (BDI > or = 13). Depressive symptoms were associated with worse self-reported functioning on the SIP and with poor memory function, but not with any of the other tests of functioning. Depressive symptoms were associated with weak SOC, but not with any of the disease-related or sociodemographic factors studied.

CONCLUSION

The prevalence of depressive symptoms in a population-based sample of PwMS is high. Given the serious nature of depression and its association with worse self-reported functioning and weak SOC, attention to, and treatment of, mental-health problems and depression are strongly indicated in the clinical management of multiple sclerosis.

Inhibition of acetylcholinesterase in CSF versus brain assessed by 11C-PMP PET in AD patients treated with galantamine

The relationship between acetylcholinesterase (AChE) activity in the CSF and brain of patients with Alzheimer's disease (AD) was investigated in 18 mild AD patients following galantamine treatment. The first 3 months of the study had a randomized double-blind placebo-controlled design, during which 12 patients received galantamine (16-24 mg/day) and six patients placebo. This was followed by 9 months galantamine treatment in all patients. Activities and protein levels of both the "read-through" AChE (AChE-R) and the synaptic (AChE-S) variants in CSF were assessed in parallel together with the regional brain AChE activity by (11)C-PMP and PET. The AChE-S inhibition was 30-36% in CSF, which correlated well with the in vivo AChE inhibition in the brain. No significant AChE inhibition was observed in the placebo group. The increased level of the AChE-R protein was 16% higher than that of AChE-S. Both the AChE inhibition and the increased level of AChE-R protein positively correlated with the patient's performance in cognitive tests associated with visuospatial ability and attention. In conclusion, AChE levels in CSF closely mirror in vivo brain AChE levels prior to and after treatment with the cholinesterase inhibitors. A positive cognitive response seems to dependent on the AChE inhibition level, which is balanced by an increased protein level of the AChE-R variant in the patients.

PET imaging of cortical 11C-nicotine binding correlates with the cognitive function of attention in Alzheimer's disease

RATIONALE

Patients suffering from Alzheimer's disease (AD) experience a marked reduction in cortical nicotinic acetylcholine receptors (nAChRs). In particular, selective loss of the alpha4beta2 nAChR subtype was observed in postmortem AD brain tissue. The alpha4 and alpha7 nAChR subunits were suggested to play an important role in cognitive function. Positron emission tomography (PET) has so far been used to visualize neuronal nAChRs in vivo by 11C-nicotine binding.

OBJECTIVES

To investigate the relationship between measures of cognitive function and in vivo 11C-nicotine binding in mild AD brain as assessed by PET.

MATERIALS AND METHODS

Twenty-seven patients with mild AD were recruited in this study. A dual tracer model with administration of 15O-water for regional cerebral blood flow and (S)(-)11C-nicotine was used to assess nicotine binding sites in the brain by PET. Cognitive function was assessed using neuropsychological tests of global cognition, episodic memory, attention, and visuospatial ability.

RESULTS

Mean cortical 11C-nicotine binding significantly correlated with the results of attention tests [Digit Symbol test (r = -0.44 and p = 0.02) and Trail Making Test A (TMT-A) (r = 0.42 and p = 0.03)]. No significant correlation was observed between 11C-nicotine binding and the results of tests of episodic memory or visuospatial ability. Regional analysis showed that 11C-nicotine binding in the frontal and parietal cortex, which are the main areas for attention, correlated significantly with the Digit Symbol test and TMT-A results.

CONCLUSION

Cortical nicotinic receptors in vivo in mild AD patients are robustly associated with the cognitive function of attention.

Identifying patients at high and low risk of cognitive decline using Rey Auditory Verbal Learning Test among middle-aged memory clinic outpatients

OBJECTIVES

To investigate whether application of cutoff levels in an episodic memory test (Rey Auditory Verbal Learning Test, RAVLT) is a useful method for identifying patients at high and low risk of cognitive decline and subsequent dementia.

METHODS

224 patients with memory complaints (mean age = 60.7 years, mean MMSE = 28.2) followed-up at a memory clinic over approximately 3 years were assigned retrospectively to one of three memory groups from their baseline results in RAVLT [severe (SIM), moderate (MIM) or no impairment (NIM)]. These groups were investigated regarding cognitive decline.

RESULTS

Patients assigned to SIM showed significant cognitive decline and progressed to dementia at a high rate, while a normal performance in RAVLT at baseline (NIM) predicted normal cognition after 3 years. Patients with MIM constituted a heterogeneous group; some patients deteriorated cognitively, while the majority remained stable or improved.

CONCLUSIONS

The application of cutoff levels in RAVLT at baseline showed that patients with severely impaired RAVLT performance were at a high risk of cognitive decline and progression to dementia, while patients with normal RAVLT results did not show cognitive decline during 3 years. Furthermore, the initial degree of memory impairment was decisive in the cognitive prognosis 3 years later.