The clinical significance of subjective memory complaints in the diagnosis of mild cognitive impairment and dementia: a meta-analysis

Comparing the relationship between subjective memory complaints, objective memory performance, and medial temporal lobe volumes in patients with mild cognitive impairment

INTRODUCTION

The current study examined the relationship between subjective memory complaints (both self- and informant-report), objective memory performance, and medial temporal lobe (MTL) volume.

METHODS

MCI patients (n=58) and their informants (n=51) completed the Memory Assessment Clinics Self (MAC-S) and Family (MAC-F) rating scales as a measure of subjective memory. RBANS Immediate and Delayed Memory indices were used as objective measures of memory and a subset of MCI participants also underwent MRI, which was used to measure MTL volume.

RESULTS

Patients reported greater difficulty with semantically based information (e.g., word and name recall) relative to informant report. However, the severity of these self-reports was unrelated to objective memory performance and only a single MAC-S scale was related to amygdalar volume. Conversely, several MAC-F indices were related to the RBANS Delayed Memory index as well as to amygdalar and hippocampal volumes. Measures of executive functioning were associated with MAC-S Frequency scales but not any MAC-F scale.

DISCUSSION

The results of the current study suggest that, in those who are cognitively symptomatic, the frequency of self-reported subjective memory difficulty may reflect executive dysfunction but holds little value for verifying memory impairment. Conversely, informant report provides meaningful information about actual memory deficits in those with MCI.

Diagnostic Value of Subjective Memory Complaints Assessed with a Single Item in Dominantly Inherited Alzheimer's Disease: Results of the DIAN Study

Objective. We examined the diagnostic value of subjective memory complaints (SMCs) assessed with a single item in a large cross-sectional cohort consisting of families with autosomal dominant Alzheimer's disease (ADAD) participating in the Dominantly Inherited Alzheimer Network (DIAN). Methods. The baseline sample of 183 mutation carriers (MCs) and 117 noncarriers (NCs) was divided according to Clinical Dementia Rating (CDR) scale into preclinical (CDR 0; MCs: n = 107; NCs: n = 109), early symptomatic (CDR 0.5; MCs: n = 48; NCs: n = 8), and dementia stage (CDR ≥ 1; MCs: n = 28; NCs: n = 0). These groups were subdivided by the presence or absence of SMCs. Results. At CDR 0, SMCs were present in 12.1% of MCs and 9.2% of NCs (P = 0.6). At CDR 0.5, SMCs were present in 66.7% of MCs and 62.5% of NCs (P = 1.0). At CDR ≥ 1, SMCs were present in 96.4% of MCs. SMCs in MCs were significantly associated with CDR, logical memory scores, Geriatric Depression Scale, education, and estimated years to onset. Conclusions. The present study shows that SMCs assessed by a single-item scale have no diagnostic value to identify preclinical ADAD in asymptomatic individuals. These results demonstrate the need of further improvement of SMC measures that should be examined in large clinical trials.

Automated Video Analysis of Handwashing Behavior as a Potential Marker of Cognitive Health in Older Adults

The identification of different stages of cognitive impairment can allow older adults to receive timely care and plan for the level of caregiving. People with existing diagnosis of cognitive impairment go through episodic phases of dementia requiring different levels of care at different times. Monitoring the cognitive status of existing patients is, thus, critical to deciding the level of care required by older adults. In this paper, we present a system to assess the cognitive status of older adults by monitoring a common activity of daily living, namely handwashing. Specifically, we extract features from handwashing trials of participants diagnosed with different levels of dementia ranging from cognitively intact to severe cognitive impairment, as assessed by the mini-mental state exam (MMSE). Based on videos of handwashing trials, we extract two classes of features: one characterizing the occupancy of different sink regions by the participant, and the other capturing the path tortuosity of the motion trajectory of participant's hands. We perform correlation analysis to assess univariate capacity of individual features to predict MMSE scores. To assess multivariate performance, we use machine learning methods to train models that predict the cognitive status (aware, mild, moderate, severe), as well as the MMSE scores. We present results demonstrating that features derived from hand washing behavior can be potential surrogate markers of a person's dementia, which can be instrumental in developing automated tools for continuously monitoring the cognitive status of older adults.

Memory Complaints in Older Adults: Prognostic Value and Stability in Reporting over Time

Objective:

The purpose of this longitudinal study was to examine the prognostic value of subjective memory complaints in 156 cognitively intact community-dwelling older adults with a mean age of 83 years.

Methods:

Participants were assessed for subjective memory complaints, cognitive performance, functional status, and mood at annual evaluations with a mean follow-up of 4.5 years.

Results:

Subjective memory complaint at entry (n = 24) was not associated with impaired memory performance and did not predict memory decline or progression to incipient dementia. Memory complaints were inconsistent across examinations for 62% of participants who reported memory problems.

Conclusion:

Memory complaints by older adults are inconsistent over time. Memory complaints’ value as a research criterion for selecting people at risk of dementia is weak among community-dwelling older adults. Age, length of follow-up, and other population characteristics may affect the implication of self-reported memory problems.

Awareness of Memory Ability and Change: (In)Accuracy of Memory Self-Assessments in Relation to Performance

Little is known about subjective assessments of memory abilities and decline among middle-aged adults or their association with objective memory performance in the general population. In this study we examined self-ratings of memory ability and change in relation to episodic memory performance in two national samples of middle-aged and older adults from the Midlife in the United States study (MIDUS II in 2005-06) and the Health and Retirement Study (HRS; every two years from 2002 to 2012). MIDUS (Study 1) participants (N=3,581) rated their memory compared to others their age and to themselves five years ago; HRS (Study 2) participants (N=14,821) rated their current memory and their memory compared to two years ago, with up to six occasions of longitudinal data over ten years. In both studies, episodic memory performance was the total number of words recalled in immediate and delayed conditions. When controlling for demographic and health correlates, self-ratings of memory abilities, but not subjective change, were related to performance. We examined accuracy by comparing subjective and objective memory ability and change. More than one third of the participants across the studies had self-assessments that were inaccurate relative to their actual level of performance and change, and accuracy differed as a function of demographic and health factors. Further understanding of self-awareness of memory abilities and change beginning in midlife may be useful for identifying early warning signs of decline, with implications regarding policies and practice for early detection and treatment of cognitive impairment.

A Simple Tool to Reach Populations at Risk for Developing Dementia and Alzheimer's Disease

Identification of individuals at high risk for developing dementia and Alzheimer's disease is a major challenge. A "memory fair" is an enjoyable and affordable tool designed to reach local population at risk, mainly those with subjective cognitive impairment (SCI) or mild cognitive impairment. The fair included a free cognitive assessment and presentation on the importance of sleep, physical activity, cognitive training, and risk-factors and provided personalized recommendations. 160 individuals completed the evaluation (69.97 ± 9.01 y, 83% women). Average Montreal Cognitive Assessment Score (MoCA) was 24.73 ± 3.71. Six percent reported SCI and an upper estimate of mild cognitive impairment prevalence was 30.7% . SCI was found to be a sensitive predictor for MoCA <26.

Risk of dementia and mild cognitive impairment in older people with subjective memory complaints: meta-analysis

OBJECTIVE

To investigate whether people with subjective memory complaints (SMC) but no objective deficits are at increased risk of developing mild cognitive impairment (MCI) and dementia.

METHOD

Major electronic databases were searched till 03/2014, and a meta-analysis was conducted using inception cohort studies.

RESULTS

Across 28 studies, there were 29,723 unique individuals (14,714 with SMC and 15,009 without SMC) (mean 71.6 years) followed on average for 4.8 years through to dementia. The annual conversion rate (ACR) of SMC to dementia was 2.33% (95% CI = 1.93%-2.78%) a relative risk (RR) of 2.07 (95% CI = 1.76-2.44) compared with those without SMC (n = 15,009). From 11 studies the ACR of developing MCI was 6.67% (95% CI = 4.70-8.95%). In long-term studies over 4 years, 14.1% (9.67-19.1%) of people with SMC developed dementia and 26.6% (95% CI = 5.3-39.7) went on to develop MCI. The ACR from SMC to dementia and MCI were comparable in community and non-community settings.

CONCLUSION

Older people with SMC but no objective complaints are twice as likely to develop dementia as individuals without SMC. Approximately 2.3% and 6.6% of older people with SMC will progress to dementia and MCI per year.

Utility of the cognitive difficulties scale and association with objective test performance

Subjective memory complaints (SMCs) are commonly noted in memory disorder clinic patients. The present study sought to examine the presence of SMCs on the Cognitive Difficulties Scale (CDS) in older adults and to examine the relationship between CDS scores and current cognitive ability. Participants were 50 adults diagnosed with possible/probable Alzheimer's disease (AD), 100 with amnestic mild cognitive impairment (MCI) and 84 cognitively healthy controls (HCs). Participants completed a neuropsychological evaluation and the self- and informant-reported CDS. Results indicated that greater self-reported SMCs were noted in the group with MCI ; however, self-reported CDS scores were associated with cognition in HCs only. Informant-reported CDS scores were predictive of cognitive ability in the diagnosis of MCI but not AD, indicating the importance of obtaining caregiver report in the evaluation of memory disorders. As AD is a neurodegenerative disorder, SMCs lose value in determining degree of cognitive impairment as disease stage increases.

The Mini-Mental State Examination as a diagnostic and screening test for delirium: systematic review and meta-analysis

OBJECTIVE

To analyse the evidence concerning the accuracy of the Mini-Mental State Examination (MMSE) as a diagnostic and screening test for the presence of delirium in adults.

METHOD

Two authors searched MEDLINE, PsychINFO and EMBASE from inception till March 2014. Articles were included that investigated the diagnostic validity of the MMSE to detect delirium against standardised criteria. A diagnostic validity meta-analysis was conducted.

RESULTS

Thirteen studies were included representing 2017 patients in medical settings of whom 29.4% had delirium. The meta-analysis revealed the MMSE had an overall sensitivity and specificity estimate of 84.1% and 73.0%, but this was 81.1% and 82.8% in a subgroup analysis involving robust high quality studies. Sensitivity was unchanged but specificity was 68.4% (95% CI = 50.9-83.5%) in studies using a predefined cutoff of <24 to signify a case. In high-risk samples where delirium was present in 25% of patients, then the Positive predictive value and Negative predictive value would be 50.9% (48.3-66.2%) and 93.2% (90.0-96.5%).

CONCLUSION

The MMSE cannot be recommended as a case-finding confirmatory test of delirium, but may be used as an initial screen to rule out high scorers who are unlikely to have delirium with approximately 93% accuracy.

Demographic, clinical, and lifestyle correlates of subjective memory complaints in the Australian population

OBJECTIVES

To provide estimates of the prevalence and correlates of subjective memory complaints in older individuals by using population-based Australian data.

DESIGN

2007 National Survey of Mental Health and Well-Being.

SETTING

Australia.

PARTICIPANTS

1,905 community-dwelling participants aged 65-85 years.

MEASUREMENTS

Subjective memory complaints were assessed by using two questions reflecting: (1) poorer memory compared with others of the same age ("worse memory"); and (2) a decline in memory performance over the previous 5 years ("declining memory"). Twelve-month and lifetime diagnoses were derived from structured diagnostic interviews. Other correlates investigated included chronic physical conditions, lifestyle factors, and service use. Analyses adjusted for scores on the Mini-Mental State Examination.

RESULTS

Subjective memory complaints were reported by one-third (33.5%) of respondents. Those who reported either complaint were more likely to report psychological distress, poor functioning, service use, and negative self-assessed mental and physical health. "Declining memory" over the past 5 years was also related to an increase in the rates of psychiatric disorders. After adjusting for other variables of interest, associations were established between subjective memory complaints and psychological distress, poor functioning, negative self-assessed mental health, and alcohol use disorders. Except for the association between "declining memory" and anxiety and depression, these associations remained significant after excluding those with scores <27 on the Mini-Mental State Examination.

CONCLUSIONS

Subjective memory complaints were associated with several negative clinical characteristics that should be considered when interpreting these complaints. Subjective memory complaints may be valid indicators of psychopathology and the need for clinical assessment.

Memory concerns, memory performance and risk of dementia in patients with mild cognitive impairment

Background

Concerns about worsening memory (“memory concerns”; MC) and impairment in memory performance are both predictors of Alzheimer's dementia (AD). The relationship of both in dementia prediction at the pre-dementia disease stage, however, is not well explored. Refined understanding of the contribution of both MC and memory performance in dementia prediction is crucial for defining at-risk populations. We examined the risk of incident AD by MC and memory performance in patients with mild cognitive impairment (MCI).

Methods

We analyzed data of 417 MCI patients from a longitudinal multicenter observational study. Patients were classified based on presence (n = 305) vs. absence (n = 112) of MC. Risk of incident AD was estimated with Cox Proportional-Hazards regression models.

Results

Risk of incident AD was increased by MC (HR = 2.55, 95%CI: 1.33–4.89), lower memory performance (HR = 0.63, 95%CI: 0.56–0.71) and ApoE4-genotype (HR = 1.89, 95%CI: 1.18–3.02). An interaction effect between MC and memory performance was observed. The predictive power of MC was greatest for patients with very mild memory impairment and decreased with increasing memory impairment.

Conclusions

Our data suggest that the power of MC as a predictor of future dementia at the MCI stage varies with the patients' level of cognitive impairment. While MC are predictive at early stage MCI, their predictive value at more advanced stages of MCI is reduced. This suggests that loss of insight related to AD may occur at the late stage of MCI.

Mild cognitive impairment

Mild cognitive impairment is the term applied to the cognitive state that lies between normal aging and dementia. There has been significant controversy around describing, defining and characterizing mild cognitive impairment. This review will cover current understanding of the condition and discuss clinical features, research strategies and future directions.

Psychological well-being in individuals with mild cognitive impairment

OBJECTIVES

Cognitive impairments associated with aging and dementia are major sources of burden, deterioration in life quality, and reduced psychological well-being (PWB). Preventative measures to both reduce incident disease and improve PWB in those afflicted are increasingly targeting individuals with mild cognitive impairment (MCI) at early disease stage. However, there is very limited information regarding the relationships between early cognitive changes and memory concern, and life quality and PWB in adults with MCI; furthermore, PWB outcomes are too commonly overlooked in intervention trials. The purpose of this study was therefore to empirically test a theoretical model of PWB in MCI in order to inform clinical intervention.

METHODS

Baseline data from a convenience sample of 100 community-dwelling adults diagnosed with MCI enrolled in the Study of Mental Activity and Regular Training (SMART) trial were collected. A series of regression analyses were performed to develop a reduced model, then hierarchical regression with the Baron Kenny test of mediation derived the final three-tiered model of PWB.

RESULTS

Significant predictors of PWB were subjective memory concern, cognitive function, evaluations of quality of life, and negative affect, with a final model explaining 61% of the variance of PWB in MCI.

DISCUSSION

Our empirical findings support a theoretical tiered model of PWB in MCI and contribute to an understanding of the way in which early subtle cognitive deficits impact upon PWB. Multiple targets and entry points for clinical intervention were identified. These include improving the cognitive difficulties associated with MCI. Additionally, these highlight the importance of reducing memory concern, addressing low mood, and suggest that improving a person's quality of life may attenuate the negative effects of depression and anxiety on PWB in this cohort.

Subjective cognitive failures after stroke in young adults: prevalent but not related to cognitive impairment

Few studies exist on subjective cognitive failures after a stroke in young adults (≤50 years) and their relation to objective cognitive performance is unknown. Therefore, we investigated the prevalence of subjective cognitive failures in patients with a stroke in young adulthood and their relation with objective cognitive impairment. This study is part of the "Follow-Up of Transient ischemic attack and stroke patients and Unelucidated Risk factor Evaluation"-study (FUTURE study), including patients, aged 18-50 years, admitted to our hospital between 1980 and 2010 with a first-ever TIA or ischemic stroke. The prevalence of subjective cognitive failures in patients was determined and compared with 146 age- and sex-matched stroke-free controls. The relation of subjective failures with objective cognitive performance was investigated with linear and logistic regression analysis. 160 patients with a TIA and 277 with an ischemic stroke were included. After a mean follow-up of 10.1 (SD 8.3) years, the prevalence of subjective memory failures was 86.4% and that of subjective executive failures was 67.4% in patients, versus 69.7% (p = 0.008) and 41.4% (p = 0.002) in controls. A weak association between subjective memory failures and objective immediate (beta -0.12, p = 0.011) and delayed memory performance (beta -0.13, p = 0.010) was observed in patients. Subjective cognitive failures are prevalent after stroke in young adults, but not strongly related to objective cognitive impairment. Therefore, extensive neuropsychological assessment is essential for determination of objective cognitive impairment. However, it is important that subjective cognitive failures are recognized as they may indicate underlying psychosocial problems.

The sensitivity and specificity of subjective memory complaints and the subjective memory rating scale, deterioration cognitive observee, mini-mental state examination, six-item screener and clock drawing test in dementia screening

BACKGROUND

The effectiveness of dementia screening depends on the availability of suitable screening tools with good sensitivity and specificity to confidently distinguish normal age-related cognitive decline from dementia. The aim of this study was to evaluate the discriminant validity of 7 screening measures for dementia.

METHODS

A sample of 140 participants aged ≥60 years living in a residential facility for the aged were assessed clinically and assigned caseness for dementia using the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, text revised diagnostic criteria. Sensitivity and specificity of a selection of the following screening measures were tested using receiver operating characteristic (ROC) analysis for individual and combined tests: the Mini-Mental State Examination (MMSE), Six-Item Screener (SIS), Subjective Memory Complaint, Subjective Memory Complaint Clinical (SMCC), Subjective Memory Rating Scale (SMRS), Deterioration Cognitive Observee (DECO) and the Clock Drawing Test (CDT).

RESULTS

Using ROC analyses, the SMCC, MMSE and CDT were found to be 'moderately accurate' in screening for dementia with an area under the curve (AUC) >0.70. The AUCs for the SIS (0.526), SMRS (0.661) and DECO (0.687) classified these measures as being 'less accurate'. At recommended cutoff scores, the SMCC had a sensitivity of 90.9% and specificity of 45.7%; the MMSE had a sensitivity of 63.6% and a specificity of 76.0%, and the CDT had a sensitivity of 44.4% and a specificity of 88.9%. Combining the SMCC and MMSE did not improve their predictive power except for a modest increase when using the sequential rule.

CONCLUSION

The SMCC is composed of valid screening questions that have high sensitivity, are simple to administer and ideal for administration at the community or primary health care level as a first level of 'rule-out' screening. The MMSE can be included at a second stage of screening at the general hospital level and the CDT in specialist clinical settings. Sequential use of the SMCC and MMSE will improve the specificity of the former and the sensitivity of the latter.

The development and validation of a patient-reported quality of life measure for people with mild cognitive impairment

BACKGROUND

No validated patient-reported outcome measure (PROM) exists specifically to assess quality of life in mild cognitive impairment (MCI); we report a study conducted to develop such a measure.

METHODS

Semi-structured in-depth interviews were carried out with 23 people with MCI in order to determine items for a draft questionnaire. These interviews were audio-recorded, transcribed, and content analyzed. The draft questionnaire was refined following feedback from a focus group. 280 questionnaires were posted to subjects recruited from memory clinics and research databases, the response rate was 56% i.e. 146 questionnaires were included in the final analysis. The completed questionnaires were analyzed using factor analytic techniques to produce the final measure; construct validity was assessed by correlation with a generic patient-reported outcome measure, the SF-12v2.

RESULTS

Factor analysis produced a 13-item measure tapping two domains of patient-reported quality of life ("Emotional Effects" and "Practical Concerns"). Internal consistency reliability was high for both domains (α was 0.91 and 0.85 respectively). Both dimensions were highly and significantly correlated with the Mental Component Summary score of the SF-12v2 ("emotional effects" ρ = -0.43, p < 0.001 and "practical concerns" ρ = -0.56, p < 0.001).

CONCLUSIONS

The Mild Cognitive Impairment Questionnaire (MCQ) is a 13-item measure developed specifically to measure patient-reported outcomes in people with MCI. It was created on the basis of patient report and has been shown to have good psychometric properties. It is likely to prove valuable in the evaluation of treatment regimes in this patient group.

Cause of death in mild cognitive impairment: a prospective study (NEDICES)

BACKGROUND AND PURPOSE

Previous studies have reported the occurrence of increased mortality rates among individuals with mild cognitive impairment (MCI), but possible links between MCI subtypes and cause-specific mortality need to be explored. To examine short-term mortality (5 years), long-term mortality (13 years) and cause-specific mortality of individuals over 65 years of age suffering from MCI compared with cognitively unimpaired individuals in the Neurological Disorders in Central Spain (NEDICES) cohort.

METHODS

Mild cognitive impairment was classified using standardized psychometric and functional assessment in accordance with diagnostic convention. Cox's proportional hazards models, adjusted by sociodemographics and comorbidity factors, were used to assess the risk of death at 5 and 13 years of MCI subtypes compared with a reference group of older people without cognitive impairment (N = 2329). Causes of death were obtained from the National Population Register of Spain.

RESULTS

There were 1484 deceased individuals at 13 years. MCI subtypes were defined as amnestic single domain (N = 259), amnestic multiple domain (N = 197) and non-amnestic (N = 641). After adjusting for covariates, only the amnestic multiple domain MCI subtype showed an increased hazard ratio (HR) for mortality at 5 years versus the reference group. However, the HR for mortality at 13 years was increased for all MCI subtypes. The HR by MCI subtype was 1.19 in the non-amnestic subtype (95% CI 1.05-1.36), 1.31 in the amnestic single domain subtype (95% CI 1.10-1.56) and 1.67 in the amnestic multiple domain subtype (95% CI 1.38-2.02). In terms of cause-specific mortality, the chance of death from dementia was statistically higher in all MCI subtypes.

CONCLUSION

Amnestic multiple domain MCI showed the greatest risk of mortality in comparison with other MCI subtypes at different intervals. Dementia was the only cause-specific mortality that was increased in MCI individuals.

Predictors of agreement between general practitioner detection of dementia and the revised Cambridge Cognitive Assessment (CAMCOG-R)

BACKGROUND

Dementia is a complex and variable condition which makes recognition of it particularly difficult in a low prevalence primary care setting. This study examined the factors associated with agreement between an objective measure of cognitive function (the revised Cambridge Cognitive Assessment, CAMCOG-R) and general practitioner (GP) clinical judgment of dementia.

METHODS

This was a cross-sectional study involving 165 GPs and 2,024 community-dwelling patients aged 75 years or older. GPs provided their clinical judgment in relation to each of their patient's dementia status. Each patient's cognitive function and depression status was measured by a research nurse using the CAMCOG-R and the 15-item Geriatric Depression Scale (GDS), respectively.

RESULTS

GPs correctly identified 44.5% of patients with CAMCOG-R dementia and 90% of patients without CAMCOG-R dementia. In those patients with CAMCOG-R dementia, two patient-dependent factors were most important for predicting agreement between the CAMCOG-R and GP judgment: the CAMCOG-R score (p = 0.006) and patient's mention of subjective memory complaints (SMC) to the GP (p = 0.040). A higher CAMCOG-R (p < 0.001) score, female gender (p = 0.005), and larger practice size (p < 0.001) were positively associated with GP agreement that the patient did not have dementia. Subjective memory complaints (p < 0.001) were more likely to result in a false-positive diagnosis of dementia.

CONCLUSIONS

Timely recognition of dementia is advocated for optimal dementia management, but early recognition of a possible dementia syndrome needs to be balanced with awareness of the likelihood of false positives in detection. Although GPs correctly agree with dimensions measured by the CAMCOG-R, improvements in sensitivity are required for earlier detection of dementia.

Increased functional connectivity and brain atrophy in elderly with subjective memory complaints

Subjective memory complaints (SMC) are common among elderly. Although subtle changes in memory functioning can hardly be determined using neuropsychological evaluation, neuroimaging studies indicate regionally smaller brain structures in elderly with SMC. Imaging of resting-state functional connectivity is sensitive to detect changes in neurodegenerative diseases, but is currently underexplored in SMC. Here, we investigate resting-state functional connectivity and brain structure in SMC. We analyzed magnetic resonance imaging data of 25 elderly with SMC and 29 age-matched controls (mean age of 71 years). Voxel-based morphometry and volume measurements of subcortical structures were employed on the structural scans using FSL. The dual regression method was used to analyze voxel-wise functional connectivity in relation to eight well-characterized resting-state networks. Group differences were studied with two-sample t-tests (p<0.05, Family-Wise Error corrected). In addition to gray matter volume reductions (hippocampus, anterior cingulate cortex (ACC), medial prefrontal cortex, cuneus, precuneus, and precentral gyrus), elderly with SMC showed increased functional connectivity in the default mode network (hippocampus, thalamus, posterior cingulate cortex (PCC), cuneus, precuneus, and superior temporal gyrus) and the medial visual network (ACC, PCC, cuneus, and precuneus). This study is the first which demonstrates that, in addition to smaller regional brain volumes, increases in functional connectivity are present in elderly with SMC. This suggests that self-reported SMC is a reflection of objective alterations in brain function. Furthermore, our results indicate that functional imaging, in addition to structural imaging, can be a useful tool to objectively determine a difference in brain integrity in SMC.

Single-subject grey matter graphs in Alzheimer's disease

Coordinated patterns of cortical morphology have been described as structural graphs and previous research has demonstrated that properties of such graphs are altered in Alzheimer's disease (AD). However, it remains unknown how these alterations are related to cognitive deficits in individuals, as such graphs are restricted to group-level analysis. In the present study we investigated this question in single-subject grey matter networks. This new method extracts large-scale structural graphs where nodes represent small cortical regions that are connected by edges when they show statistical similarity. Using this method, unweighted and undirected networks were extracted from T1 weighted structural magnetic resonance imaging scans of 38 AD patients (19 female, average age 72±4 years) and 38 controls (19 females, average age 72±4 years). Group comparisons of standard graph properties were performed after correcting for grey matter volumetric measurements and were correlated to scores of general cognitive functioning. AD networks were characterised by a more random topology as indicated by a decreased small world coefficient (p = 3.53×10(-5)), decreased normalized clustering coefficient (p = 7.25×10(-6)) and decreased normalized path length (p = 1.91×10(-7)). Reduced normalized path length explained significantly (p = 0.004) more variance in measurements of general cognitive decline (32%) in comparison to volumetric measurements (9%). Altered path length of the parahippocampal gyrus, hippocampus, fusiform gyrus and precuneus showed the strongest relationship with cognitive decline. The present results suggest that single-subject grey matter graphs provide a concise quantification of cortical structure that has clinical value, which might be of particular importance for disease prognosis. These findings contribute to a better understanding of structural alterations and cognitive dysfunction in AD.

AD dementia risk in late MCI, in early MCI, and in subjective memory impairment

OBJECTIVE

To compare the risk of developing Alzheimer's disease (AD) dementia in late mild cognitive impairment (LMCI), early MCI (EMCI), and subjective memory impairment (SMI) with normal test performance.

METHODS

The baseline sample (n = 2892) of the prospective cohort study in nondemented individuals (German Study on Aging, Cognition and Dementia in Primary Care Patients) was divided into LMCI, EMCI, SMI, and control subjects by delayed recall performance. These groups were subdivided by the presence of self-reported concerns associated with experienced memory impairment. AD dementia risk was assessed over 6 years.

RESULTS

Across all groups, risk of AD dementia was greatest in LMCI. In those with self-reported concerns regarding their memory impairment, SMI and EMCI were associated with a similarly increased risk of AD dementia. In those subgroups without concerns, SMI was not associated with increased risk of AD dementia, but EMCI remained an at-risk condition.

CONCLUSIONS

SMI and EMCI with self-reported concerns were associated with the same risk of AD dementia, suggesting that pre-LMCI risk conditions should be extended to SMI with concerns.

Are subjective cognitive complaints relevant in preclinical Alzheimer's disease? A review and guidelines for healthcare professionals

Identifying what makes people vulnerable to developing Alzheimer's disease (AD) is at the forefront of many research programmes, while early diagnosis is the goal in clinical practice. What individuals themselves tell their general practitioners (GPs) is clearly important because these subjective complaints may be a clue that something is wrong. More specifically, subjective cognitive complaints (SCC) may be the first sign of AD in individuals whose cognitive performance on standard neuropsychological tasks is normal for their age. The challenge for researchers in this field is twofold: (a) determining when SCC do or do not predict current cognitive functioning and future dementia; and (b) estimating how relevant they are for patients and their proxies. The current article addresses these issues, while guidelines are also provided in an attempt to help clinicians interpret and make treatment decisions about their patients’ SCC.

Cross-sectional association between polyfluoroalkyl chemicals and cognitive limitation in the National Health and Nutrition Examination Survey

BACKGROUND/AIMS

Our limited understanding of how polyfluoroalkyl chemicals (PFCs) may impact on human health suggests the potential for a protective impact on brain health. This study was designed to explore the association between PFCs and cognitive ability in older adults.

METHODS

We assessed the association between four PFCs, perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorononanoic acid (PFNA) and perfluorohexane sulfonic acid (PFHxS), and self-reported limitation due to difficulty remembering or periods of confusion using data from participants aged 60-85 years from the 1999-2000 and 2003-2008 National Health and Nutrition Examination Surveys. We also considered whether diabetic status or diabetic medication use modifies this association in light of in vitro evidence that PFCs may act on the same receptors as some diabetic medications.

RESULTS

In multivariable adjusted models, point estimates suggest a protective association between PFCs and self-reported cognitive limitation (odds ratio, OR; 95% confidence interval, CI) for a doubling in PFC concentration: PFOS (OR, 0.90; 95% CI, 0.78, 1.03), PFOA (OR, 0.92; 95% CI, 0.78, 1.09), PFNA (OR, 0.91; 95% CI, 0.79, 1.04) and PFHxS (OR, 0.93; 95% CI, 0.82, 1.06). The protective association was concentrated in diabetics, with strong, significant protective associations in nonmedicated diabetics.

CONCLUSIONS

This cross-sectional study suggests that there may be a protective association between exposure to PFCs and cognition in older adults, particularly diabetics.

Intraindividual cognitive decline using a brief computerized cognitive screening test

BACKGROUND

Progressive intraindividual decline in memory and cognition is characteristic of dementia and may be useful in detecting very early Alzheimer's disease pathology.

METHODS

This study evaluated the slopes of cognitive performance over a 12-month period in 263 healthy, community-dwelling, adult volunteers aged ≥50 years. Participants completed a brief computerized battery of cognitive tests (CogState) at baseline and during 3-, 6-, 9-, and 12-month follow-up assessments. Linear mixed models were used to estimate age-adjusted mean slopes and 95% confidence intervals of change for each of the cognitive measures.

RESULTS

By defining age-adjusted mean slopes, and 95% confidence intervals for a measure of episodic memory, individuals with greater than expected decline (equal to or lower than the fifth percentile level of decline) were identified. From these, four individuals completed a full medical, neurologic, and neuropsychological evaluation, with none of them fulfilling criteria for mild cognitive impairment, but three (75%) having positive amyloid-positron emission tomographic scans.

CONCLUSIONS

Intraindividual decline in cognitive performance can be detected in otherwise healthy, community-dwelling, older persons, and this may deserve further study as a potential indicator of early Alzheimer's disease pathology.

Early dysfunction of functional connectivity in healthy elderly with subjective memory complaints

It is still an open question whether subjective memory complaints (SMC) can actually be considered to be clinically relevant predictors for the development of an objective memory impairment and even dementia. There is growing evidence that suggests that SMC are associated with an increased risk of dementia and with the presence of biological correlates of early Alzheimer's disease. In this paper, in order to shed some light on this issue, we try to discern whether subjects with SMC showed a different profile of functional connectivity compared with subjects with mild cognitive impairment (MCI) and healthy elderly subjects. In the present study, we compare the degree of synchronization of brain signals recorded with magnetoencephalography between three groups of subjects (56 in total): 19 with MCI, 12 with SMC and 25 healthy controls during a memory task. Synchronization likelihood, an index based on the theory of nonlinear dynamical systems, was used to measure functional connectivity. Briefly, results show that subjects with SMC have a very similar pattern of connectivity to control group, but on average, they present a lower synchronization value. These results could indicate that SMC are representing an initial stage with a hypo-synchronization (in comparison with the control group) where the brain system is still not compensating for the failing memory networks, but behaving as controls when compared with the MCI subjects.

Memory complaints associated with seeking clinical care

Diagnosis of mild cognitive impairment relies on the presence of memory complaints. However, memory complaints are very frequent in healthy people. The objective of this study was to determine the severity and type of memory difficulties presented by elderly patients who seek for clinical help, as compared to the memory difficulties reported by subjects in the community. Assessment of subjective memory complaints was done with the subjective memory complaints scale (SMC). The mini-mental state examination was used for general cognitive evaluation and the geriatric depression scale for the assessment of depressive symptoms. Eight-hundred and seventy-one nondemented subjects older than 50 years were included. Participants in the clinical setting had a higher total SMC score (10.3 ± 4.2) than those in the community (5.1 ± 3.0). Item 3 of the SMC, Do you ever forget names of family members or friends? contributed significantly more to the variance of the total SMC score in the clinical sample (18%) as compared to the community sample (11%). Forgetting names of family members or friends plays an important role in subjective memory complaints in the clinical setting. This symptom is possibly perceived as particularly worrisome and likely drives people to seek for clinical help.

Validation of simple visual-analogue thermometer screen for mood complications of cardiovascular disease: the Emotion Thermometers

OBJECTIVE

Conventional scales may help with the identification of depression but are generally too lengthy for clinical practice and perform poorly against anxiety and distress. We therefore examined the value of a single item NCCN Distress Thermometer and an enhanced visual-analogue method (Emotion Thermometers, ET) that incorporates four emotion thermometers.

METHODS

We examined 228 patients with mixed cardiovascular conditions of whom 200 completed questionnaires. 64.5% suffered from cardiomyopathy/congestive heart failure, 9.5% had coronary artery disease, 4.5% had multiple cardiac diagnoses, 3% suffered from hypertension, 2% had rhythm problem, 2% had valve problems and 1.5% were diagnosed with atrial fibrillation. We used DSM-IV criteria to define current depression, the GAD7 to define current anxiety and the HADS-T to define distress. 13% had DSM-IV MDD and 19.1% had major or minor depression using DSM-IV (any depression). There were also 59 people (29.6%) with clinically significant distress and 46 with clinically significant anxiety (23.1%).

RESULTS

The optimal accuracy for major depression was either the Depression thermometer (DepT) or the Help thermometer (HelpT), as both performed well. They had a sensitivity and specificity of 73.1%, 89.7% and 84.6%, 85.6%, respectively. The DepT was also best for detecting any DSM-IV depression (sensitivity 68.4% and specificity 93.2%) and HAD-T based distress (sensitivity 79.7% and specificity 82.9%). The Anxiety thermometer (AnxT) performed best against the GAD7 (sensitivity 84.8% and specificity 83.7%).

CONCLUSION

Innovative visual-analogue screening tools for mood appear to perform well in cardiovascular settings.

Self-reported depressive symptoms and memory complaints in survivors five years after ARDS

BACKGROUND

Survivors of ARDS report depressive symptoms and memory complaints, the prevalence of which after 5 years is unknown.

METHODS

We administered instruments assessing symptoms of depression (Beck Depression Inventory II [BDI-II]) and memory complaints (Memory Assessment Clinics Self-Rating Scale [MAC-S]) to 64 survivors of ARDS from four university-affiliated ICUs 5 years after ICU discharge. We compared BDI-II scores to quality of life (Medical Outcomes Study 36-Item Short Form [SF-36]) mental health domains (role emotional, mental health, mental component summary), compared BDI-II and MAC-S scores to earlier scores (median, 22 months postdischarge), and examined return to work.

RESULTS

Forty-three (67.2%), 46 (71.9%), and 38 (59.4%) patients fully completed the BDI-II, MAC-S ability subscale, and MAC-S frequency of occurrence subscale, respectively. Responders were young (median, 48 years; first-third quartile [Q1-Q3], 39-61 years) with high illness severity. The median BDI-II score was 10 (Q1-Q3, 3-18); eight of 43 (18.6%) had moderate to severe depressive symptoms compared with 14 of 43 (32.6%) earlier (P = .15, n = 38 with paired data). Median MAC-S ability and MAC-S frequency scores were 81 (Q1-Q3, 57-92) and 91.5 (Q1-Q3, 76-105), respectively, similar to earlier scores (P = .67 and P = .64, respectively); 0% to 4.3% scored > 2 SDs below population norms. Higher BDI-II score was predicted by higher earlier BDI-II score, slower recovery of organ function, and longer duration of mechanical ventilation and ICU stay. Higher MAC-S score was predicted by higher earlier MAC-S score. SF-36 mental health domain scores were very stable (P = .57-.83). BDI-II and SF-36 mental health domains were negatively correlated (Spearman coefficient, -0.50 to -0.82). Most patients returned to work regardless of depressive symptoms (minimal to mild, 31 of 35 [88.6%]; moderate to severe, five of eight [62.5%]; P = .12).

CONCLUSIONS

Compared with ∼ 2 years postdischarge from the ICU, depressive symptoms and memory complaints were similar at 5 years. Mental health domains of the SF-36 may not be sensitive to small changes in mood symptoms.

Clinical recognition of dementia and cognitive impairment in primary care: a meta-analysis of physician accuracy

OBJECTIVE

We aimed to examine the ability of the general practitioners (GPs) to recognize a spectrum of cognitive impairment from mild cognitive impairment (MCI) to severe dementia in routine practice using their own clinical judgment.

METHOD

Using PRISMA criteria, a meta-analysis of studies testing clinical judgment and clinical documentation was conducted against semi-structured interviews (for dementia) and cognitive tests (for cognitive impairment). We located 15 studies reporting on dementia, seven studies that examined recognition of broadly defined cognitive impairment, and eight regarding MCI.

RESULTS

By clinical judgment, clinicians were able to identify 73.4% of people with dementia and 75.5% of those without dementia but they made correct annotations in medical records in only 37.9% of cases (and 90.5% of non-cases). For cognitive impairment, detection sensitivity was 62.8% by clinician judgment but 33.1% according to medical records. Specificity was 92.6% for those without cognitive impairment by clinical judgment. Regarding MCI, GPs recognized 44.7% of people with MCI, although this was recorded in medical notes only 10.9% of the time. Their ability to identify healthy individuals without MCI was between 87.3% and 95.5% (detection specificity).

CONCLUSION

GPs have considerable difficulty identifying those with MCI and those with mild dementia and are generally poor at recording such diagnoses in medical records.

Test Your Memory test: diagnostic utility in a memory clinic population

BACKGROUND

Test Your Memory (TYM) test is a recently described cognitive test instrument designed to be self-administered under medical supervision. The pragmatic role of such self-administered tests in cognitive clinics has not previously been examined. We investigated the diagnostic utility of the TYM as an independent test to differentiate patients with and without dementia at initial clinical diagnostic interview in dedicated memory clinics.

METHODS

TYM was administered to consecutive new patient referrals to two memory clinics independent of other tests [Mini-Mental State Examination (MMSE) and the Addenbrooke's Cognitive Examination-Revised] which were used to establish diagnoses according to standard diagnostic criteria (DSM-IV), and results were compared.

RESULTS

In a cohort of 224 patients, 35% fulfilling clinical diagnostic criteria for dementia, TYM proved easy to use and acceptable to patients. Downward adjustment of the TYM test cutoff to ≤30/50, compared to ≤42/50 used in the index study, proved necessary to maximise test accuracy and specificity. Using this revised cutoff, TYM showed comparable diagnostic utility (sensitivity 0.73, specificity 0.88, positive predictive value 0.77, negative predictive value 0.86 and area under receiver operating characteristic curve 0.89) to the MMSE and the Addenbrooke's Cognitive Examination-Revised for the differentiation of cases of dementia from non-dementia.

CONCLUSIONS

TYM is a useful screening test in the cognitive function clinic setting, with patients who fall below the designated cutoff requiring further investigation to ascertain a cause for their cognitive impairment. Self-administered tests such as TYM may be of particular value in situations where clinician time is limited.

Impaired digit span can predict further cognitive decline in older people with subjective memory complaint: a preliminary result

Subjective memory complaint (SMC) is common among elderly people, and is thought to be part of mild cognitive impairment (MCI). We evaluated whether impaired digit span (IDS) in older people with SMC can predict wider impairment in future neuropsychological tests that correspond to MCI. After a mean of 6.6 years from the initial assessment, we reevaluated 16 subjects with SMC and normal digit span (NDS) scores (mean age 57.6 ± 8.1 years) and 28 subjects with SMC and IDS scores (mean age 59.7 ± 9.9 years). The IDS group showed wider cognitive decline in tests of short-term verbal memory and category verbal fluency compared to the NDS group. IDS scores indicate an earlier step for conversion of SMC to MCI.

Subjective report of word-finding and memory deficits in normal aging and dementia

OBJECTIVE

Compare subjective reports of both memory and word-finding deficits to clinical diagnosis and objective neuropsychological testing.

BACKGROUND

With the increasing number of aging individuals with cognitive impairments, effective screening measures would improve the likelihood of detection. Subjective reports of symptoms are typically obtained in clinical settings, yet the validity of these reports is relatively unknown.

METHODS

Clinical screening for dementia was carried out at an Alzheimer disease center. Dichotomous ratings for memory and word-finding/language problems were given by patients and neurologists. These ratings were compared with 13 neuropsychological measures of word-finding/language and episodic memory.

RESULTS

Ratings of memory by both patients and neurologists correlated well with standard neuropsychological measures of memory. However, both the patients' and physicians' ratings of word-finding/language impairments had notably less of a correlation with the relevant neuropsychological measures of word-finding/language.

CONCLUSION

Compared with ratings of memory, similar assessments of word-finding/language difficulties were relatively inaccurate, and thus poor predictors of impairment. It is imperative to develop effective screening methods that will help reveal cognitive impairments, as this issue will almost certainly become more pressing given the projected increase in the number of aging individuals and those with dementia.

Diagnostic validity of the Hospital Anxiety and Depression Scale (HADS) in cancer and palliative settings: a meta-analysis

OBJECTIVE

To examine the validity of the Hospital Anxiety and Depression Scale (HADS) in the identification of psychiatric complications of cancer, as defined by a robust criterion standard.

METHODS

50 analyses tested the depression subscale (HADS-D), anxiety subscale (HADS-A) or combined scales (HADS-T) against syndromal (clinical) depression (n=22), syndromal anxiety (n=4) or any mental ill health/distress (n=24), all defined by semi-structured psychiatric interview.

RESULTS

The HADS and its subscales had both strengths and limitations. Overall it appeared to perform marginally better in non-palliative cancer settings. Specific findings for each subscale were as follows. In the identification of depression the HADS-T, HADS-D and HADS-A had a pooled sensitivity and specificity of 82.0%, 77.0%; 71.6%, 82.6% and 80.5%, 77.8%, respectively. All versions performed poorly in case-finding but well in a screening capacity. For anxiety there were no HADS-D studies. The HADS-T and HADS-A had a pooled sensitivity and specificity of 83.9%, 69.9% and 48.7%, 78.7%. They were poor at case-finding but good as screening instruments. For distress (any mental ill health) the HADS-T, HADS-D and HADS-A had a pooled sensitivity and specificity of 72.8%, 80.6%; 75.7%, 66.3% and 65.7%, 71.3%, respectively. When screening for distress and anxiety the HADS-T was the optimal subscale.

CONCLUSION

For the identification of depression, anxiety or distress in cancer settings, the HADS (including subscales) is not recommended as a case-finding instrument but it may, subject to concerns about its length, be a suitable addition to screening programme.

Increased biomagnetic activity in healthy elderly with subjective memory complaints

OBJECTIVE

Subjective memory complaints (SMCs) are frequently reported by elderly people with or without objective cognitive impairment (OMI) as assessed by neuropsychological tests. We investigate whether SMCs are associated with altered brain biomagnetic patterns even in the absence of OMI.

METHODS

We report spatio-temporal patterns of brain magnetic activity recorded with magnetoencephalography during a memory task in 51 elderly participants divided into the following groups: patients with mild cognitive impairment (MCI) with SMC and OMI, individuals with SMC but not OMI, and healthy controls without neither SMC nor OMI. Exclusion criteria for all three groups included a diagnosis of depression or any other psychiatric condition.

RESULTS

No statistically significant differences were found between MCI patients and participants with SMC. However, the SMC showed higher activation, between 200 and 900 ms after stimulus onset, than the control group in posterior ventral regions and in the dorsal pathway. MCI patients showed higher activation than the control group in the posterior part of the ventral pathway.

CONCLUSIONS

These findings suggest that similar physiological mechanisms may underlie SMC and MCI, which could be two stages in a cognitive continuum.

SIGNIFICANCE

MEG provide different neurophysiological profiles between SMC and control subjects.

Diagnostic validity and added value of the Geriatric Depression Scale for depression in primary care: a meta-analysis of GDS30 and GDS15

BACKGROUND

The Geriatric Depression Scale (GDS) has been evaluated in hospital settings but its validity and added value in primary care is uncertain. We therefore conducted a meta-analysis analysing the diagnostic accuracy, clinical utility and added value of the GDS in primary care.

METHODS

A comprehensive search identified 69 studies that measured the diagnostic validity of the GDS against a semi-structured psychiatric interview and of these 17 analyses (in 14 publications) took place in primary care. Seven studies examined the GDS(30) and 10 studies examined the GDS(15). Heterogeneity was moderate to high, therefore random effects meta-analysis was used.

RESULTS

Diagnostic accuracy of the GDS(30) after meta-analytic weighting was given by a sensitivity of 77.4% (95% CI=66.3% to 86.8%) and a specificity=65.4% (95% CI=44.2% to 83.8%). For the GDS(15) the sensitivity was 81.3% (95% CI=77.2% to 85.2%) and specificity=78.4% (95% CI=71.2% to 84.8%). The fraction correctly identified (also known as efficiency) by the GDS(15) was significantly higher than the GDS(30) (77.6% vs 71.2%, Chi(2)=24.8 P<0.0001). The clinical utility of both the GDS(30) and GDS(15) was "poor" for case-finding (UI+ 0.29, UI+ 0.32 respectively). However the GDS(15) was rated as "good" for screening (UI- 0.75) whereas the GDS(30) was "adequate" (UI- 0.60). Concerning added value, when identification using the GDS was compared with general practitioners' ability to diagnose late-life depressions unassisted by tools, at a prevalence of 15% the GDS(30) had no added benefit whereas the GDS(15) helped identify an additional 4 cases per 100 primary care attendees and also helped rule-out an additional 4 non-cases per 100 attendees. Thus we estimate the potential gain of the GDS(15) in primary care to be 8% over unassisted clinical detection but at a cost of 3-4 minutes of extra time per appointment.

CONCLUSION

The GDS yields potential added value in primary care. We recommend the GDS(15) but not the GDS(30) in the diagnosis of late-life depression in primary care.

Changes in neuronal activation patterns in response to androgen deprivation therapy: a pilot study

BACKGROUND

A common treatment option for men with prostate cancer is androgen deprivation therapy (ADT). However, men undergoing ADT may experience physical side effects, changes in quality of life and sometimes psychiatric and cognitive side effects.

METHODS

In this study, hormone naïve patients without evidence of metastases with a rising PSA were treated with nine months of ADT. Functional magnetic resonance imaging (fMRI) of the brain during three visuospatial tasks was performed at baseline prior to treatment and after nine months of ADT in five subjects. Seven healthy control patients, underwent neuroimaging at the same time intervals.

RESULTS

ADT patients showed reduced, task-related BOLD-fMRI activation during treatment that was not observed in control subjects. Reduction in activation in right parietal-occipital regions from baseline was observed during recall of the spatial location of objects and mental rotation.

CONCLUSIONS

Findings, while preliminary, suggest that ADT reduces task-related neural activation in brain regions that are involved in mental rotation and accurate recall of spatial information.

Apart from nihilism and stigma: what influences general practitioners' accuracy in identifying incident dementia?

OBJECTIVES

To assess the accuracy of the General Practitioner's (GP) judgment in the recognition of incident dementia cases and to explore factors associated with recognition.

DESIGN

Prospective observational cohort study, two follow-up assessments (FU 1 and FU 2) within 3 years after baseline.

SETTING

One hundred thirty-eight general practice surgeries in the six study centers of a prospective German study.

PARTICIPANTS

Participants were between 75 and 89 years of age at baseline and were recruited from the GPs' patient lists. In FU 1, 2,402 patients and in FU 2, 2,177 patients were analyzed.

MEASUREMENTS

GPs' judgments on their patients' cognitive status as index test; at-home patient interviews and tests, consensus diagnosis as reference; validity of the GP judgment; associations between patient factors and GPs' dementia recognition.

RESULTS

One hundred eleven incident dementia cases with complete data were identified in FU 1 and FU 2. Overall sensitivity of the GP judgment was 51.4%, specificity 95.9%, positive predictive value 23.6%, and negative predictive value 98.8%. GPs missed dementia more frequently in patients living alone. GPs overrated the presence of dementia more frequently in patients with problems in mobility or hearing, in patients with memory complaints, and in patients with a GP-documented depression.

CONCLUSION

GPs miss nearly half of incident dementia cases. They should be alert not to miss dementia in patients living alone. Without seeking additional information, a positive GP judgment seems not sufficient for case finding. GPs should be aware of their tendency to overestimate dementia in depressed and frail patients.