Clock drawing is sensitive to executive control: a comparison of six methods

Conventional clock drawing tests have low to moderate reliability and validity for detecting subtle cognitive impairments in community-dwelling older adults

Background

Early identification of subtle cognitive decline in community-dwelling older adults is critical, as mild cognitive impairment contributes to disability and can be a precursor to dementia. The clock drawing test (CDT) is a widely adopted cognitive screening measure for dementia, however, the reliability and validity of paper-and-pencil CDT scoring scales for mild cognitive impairment in community samples of older adults is less well established. We examined the reliability, sensitivity and specificity, and construct validity of two free-drawn clock drawing test scales-the Rouleau System and the Clock Drawing Interpretation Scale (CDIS)-for subtle cognitive decline in community-dwelling older adults.

Methods

We analyzed Rouleau and CDIS scores of 310 community-dwelling older adults who had MoCA scores of 20 or above. For each scale we computed Cronbach's alpha, receiver operating characteristic curves (ROC) for sensitivity and specificity using the MoCA as the index measure, and item response theory models for difficulty level.

Results

Our sample was 75% female and 85% Caucasian with a mean education of 16 years. The Rouleau scale had excellent interrater reliability (94%), poor internal consistency [0.37 (0.48)], low sensitivity (0.59) and moderate specificity (0.71) at a score of 9. The CDIS scale had good interrater reliability (88%), moderate internal consistency [0.66 (0.09)], moderate sensitivity (0.78) and low specificity (0.45) at a score of 19. In the item response models, both scales' total scores gave the most information at lower cognitive levels.

Conclusion

In our community-dwelling sample, the CDIS's psychometric properties were better in most respects than the Rouleau for use as a screening instrument. Both scales provide valuable information to clinicians screening older adults for cognitive change, but should be interpreted in the setting of a global cognitive battery and not as stand-alone instruments.

Cultural influence on clock drawing test: A systematic review

OBJECTIVE

Dementia among migrants is an emerging phenomenon worldwide and the development of neuropsychological tests sensitive to cultural differences is increasingly regarded as a priority. The Clock Drawing Test (CDT) is one of the most used screening tools for the detection of cognitive decline. Nevertheless, there is still a debate about its adoption as a cross-cultural assessment.

METHODS

To identify cultural variables influencing performance at CDT, we performed a systematic review of literature on three databases of all studies considering the role of at least one of the following: (1) language; (2) education; (3) literacy; (4) acculturation; and (5) ethnicity.

RESULTS

We extrapolated 160 analyses from 105 studies. Overall, an influence of cultural determinants on performance at CDT was found in 127 analyses (79.4%). Regarding specific cultural factors, 22 analyses investigated the effect of ethnicity on CDT scores, reporting conflicting results. Only two scoring systems turned out to be sufficiently accurate in a multicultural population. Language influenced performance in only 1 out of 8 analyses. A higher level of education positively influenced test performance in 118 out of 154 analyses (76.6%), and a better quality of education in 1 analysis out of 2. A negative influence of illiteracy on CDT performance emerged in 9 out of 10 analyses. Acculturation affected performances at CDT in 1 out of 2 studies.

CONCLUSIONS

Based on the present findings, caution is needed when using CDT in a multicultural context, even if it requires limited linguistic competence.

Diagnostic performance and neural basis of the combination of free- and pre-drawn Clock Drawing Test

OBJECTIVES

This study aimed to clarify the diagnostic performance and neural basis of the Clock Drawing Test (CDT) combining free- and pre-drawn methods.

METHODS

This retrospective study included 165 participants (91 with Alzheimer disease [AD], 52 with amnestic mild cognitive impairment [aMCI], and 22 healthy controls [HC]), who were divided into four groups according to their free- and pre-drawn CDT scores: group 1, could do both; group 2, impaired in both; group 3, impaired in pre-drawn CDT; and group 4, impaired in free-drawn CDT. The diagnostic performances of the free-drawn, pre-drawn, and combination methods were compared using receiver operating characteristics analysis; in voxel-based morphometry analysis, the gray matter (GM) volume of groups 2-4 were compared with that of group 1.

RESULTS

The area under the curve of the combination method was greater than that of the free- or pre-drawn method alone when comparing AD with HC or aMCI. Group 2 had a significantly smaller GM volume in the bilateral temporal lobes than group 1. Group 3 had a trend toward smaller GM volumes in the right temporal lobe when a liberal threshold was applied. Group 4 had significantly smaller GM volumes in the left temporal lobe than group 1.

CONCLUSIONS

This study suggests that the combination method may be able to screen for a wider range of brain dysfunction. Combined use of free- and pre-drawn CDT may be useful for screening for AD and its early detection and treatment.

Information and Communication Technology Use in Older Adults: A Unidirectional or Bi-directional Association with Cognitive Function?

Previous research on older adults' information and communication technology (ICT) use has shown that cognitive function is linked with ICT use; however, the direction of influence has been yet to be determined. The current study examined the temporal sequence of ICT use and cognitive performance. Using three waves (2013, 2015, and 2017) from the National Health and Aging Trends Study, a total of 3,904 community-dwelling older adults aged 65 and above were selected for the analysis. Two cognitive domains were considered: episodic memory and executive function. Reciprocal 4-year lagged associations between ICT use and each cognitive domain were examined, controlling for covariates (age, gender, education, race/ethnicity, and depression). Greater use of ICT was significantly associated with memory performance, B (SE) = .19 (.01), p < .001, and executive function, B (SE) = .26 (.01), p < .001, in following years. Reciprocally, episodic memory predicted ICT use, B (SE) = .02 (.01), p < .001, 2 years later. However, the cross-lagged effect of executive functioning on ICT use was not significant, B (SE) = .00 (.01), p = .14. These results suggest the direction of the association between ICT use and cognitive performance might vary depending on the cognitive domain.

Tablet Technology for Writing and Drawing during Functional Magnetic Resonance Imaging: A Review

Functional magnetic resonance imaging (fMRI) is a powerful modality to study brain activity. To approximate naturalistic writing and drawing behaviours inside the scanner, many fMRI-compatible tablet technologies have been developed. The digitizing feature of the tablets also allows examination of behavioural kinematics with greater detail than using paper. With enhanced ecological validity, tablet devices have advanced the fields of neuropsychological tests, neurosurgery, and neurolinguistics. Specifically, tablet devices have been used to adopt many traditional paper-based writing and drawing neuropsychological tests for fMRI. In functional neurosurgery, tablet technologies have enabled intra-operative brain mapping during awake craniotomy in brain tumour patients, as well as quantitative tremor assessment for treatment outcome monitoring. Tablet devices also play an important role in identifying the neural correlates of writing in the healthy and diseased brain. The fMRI-compatible tablets provide an excellent platform to support naturalistic motor responses and examine detailed behavioural kinematics.

Dual-tasking in older women: physical activity or else?

The interplay between gender, Physical Activity (PA), and Dual Tasking (DT) in older adults is unclear. This study aimed to address DT based on gender and PA level. One-hundred and twenty older adults (81 women and 39 men) participated. Timed up and go test and spatiotemporal gait measures were collected in single and DT conditions. Participants were grouped according to gender and PA level. Physical activity did not explain gender differences, women were slower and had shorter stride lengths when DT regardless of PA level. Findings indicate the necessity for tailored PA and functional interventions to improve women's performance.

Daily exposure to digital displays may affect the clock-drawing test: from psychometrics to serendipity

BACKGROUND

The clock-drawing test (CDT) is a neuropsychological screening tool largely used to explore cognitive functioning. It requires participants to draw an analog clock face. Many studies have reported a good correlation between the CDT and the Mini-Mental State Examination (MMSE). The CDT has also showed a variable specificity. There are, however, some inconsistencies concerning the effect of sociodemographic variables (sex, age, education) on clock-drawing abilities. The present study aimed at examining these issues in a sample of middle-aged/young-old healthy adults.

METHOD

Participants (n = 97) performed the MMSE and CDT. Clock drawings were assessed by five formal scoring systems (Wolf-Klein, Watson, Freedman, Manos, Shulman). In addition, three naïve raters provided a dichotomous judgment (normal vs. abnormal) for each clock.

RESULTS

Sociodemographic variables did not affect CDT performance. Unlike earlier studies, CDT scores did not correlate with MMSE. Moreover, test specificity was appropriate only for Freedman's, Shulman's, and Wolf-Klein's methods. Interestingly, some participants drew clocks with numbers as they appear in digital clocks. By re-running the statistical analyses after removing these atypical clocks, four out of the five formal scores showed a significant correlation with MMSE; furthermore, CDT specificity slightly increased for all scoring systems including naïve ratings.

CONCLUSIONS

CDT is not affected by sociodemographic variables. The finding of some clocks with digitally represented numbers suggests the need to align neuropsychological assessments with demands from an increasing digitalized environment. Moreover, the occurrence of high false-positives and possible digital contaminations suggest great caution in interpreting the clinical significance of CDT.

Predicting medication adherence in older Hispanic patients with type 2 diabetes

PURPOSE

Potential cognitive and demographic correlates of medication nonadherence in older Hispanic adults with type 2 diabetes were investigated.

METHODS

Forty community-dwelling participants 65 years of age or older were recruited. Executive control function (ECF) was assessed using the executive clock drawing task (CLOX 1) test and the 25-item Executive Interview. Self-reported medication adherence was measured on a visual analog scale (VAS); measures of glycemic control included glycosylated hemoglobin (HbA_1c) concentration. The primary objective was to determine if ECF performance correlated with medication adherence or glycemic control.

RESULTS

Participants' mean ± S.D. age was 74.95 ± 7.07 years, and 73% (n = 29) were female. Lower VAS scores correlated with worse CLOX 1 performance (r = 0.38, p = 0.02) and worse HbA_1c status (r = -0.42, p = 0.007). Linear regression modeling indicated significant associations between VAS scores and both CLOX 1 results (beta coefficient [β] = 0.41, p = 0.01) and educational level (β = 0.345, p = 0.03). Receiver operating characteristic analysis of CLOX 1 scores (scoring range, 0-15; lower scores indicate greater impairment) showed that a highly sensitive cutoff score for predicting adherence of <90% would be 7, but a cutoff of 10 would provide more specificity.

CONCLUSION

Results of an evaluation of a small sample of Hispanic older adults with type 2 diabetes demonstrated a relationship between ECF, as measured by the CLOX 1 instrument, and self-reported medication adherence.

The Neural Correlates of the Clock-Drawing Test in Healthy Aging

Importance: The clock-drawing test (CDT) is an important neurocognitive assessment tool, widely used as a screening test for dementia. Behavioral performance on the test has been studied extensively, but there is scant literature on the underlying neural correlates.

Purpose: To administer the CDT naturalistically to a healthy older aging population in an MRI environment, and characterize the brain activity associated with test completion.

Main Outcome and Measure: Blood-oxygen-level dependent (BOLD) functional MRI was conducted as participants completed the CDT using novel tablet technology. Brain activity during CDT performance was contrasted to rest periods of visual fixation. Performance on the CDT was evaluated using a standardized scoring system (Rouleau score) and time to test completion. To assess convergent validity, performance during fMRI was compared to performance on a standard paper version of the task, administered in a psychometric testing room.

Results: Study findings are reported for 33 cognitively healthy older participants aged 52–85. Activation was observed in the bilateral frontal, occipital and parietal lobes as well as the supplementary motor area and precentral gyri. Increased age was significantly correlated with Rouleau scores on the clock number drawing (R2) component (rho = -0.55, p < 0.001); the clock hand drawing (R3) component (rho = -0.50, p < 0.005); and the total clock (rho = -0.62, p < 0.001). Increased age was also associated with decreased activity in the bilateral parietal and occipital lobes as well as the right temporal lobe and right motor areas.

Conclusion and Relevance: This imaging study characterizes the brain activity underlying performance of the CDT in a healthy older aging population using the most naturalistic version of the task to date. The results suggest that the functions of the occipital and parietal lobe are significantly altered by the normal aging process, which may lead to performance decrements.

Association Between Executive Dysfunction and Instrumental Activities of Daily Living: Racial and Ethnic Differences Among Community-Dwelling Older Adults in the Southeastern US

OBJECTIVE

Examining cultural differences in assessment of cognitive/functional disability among older Americans is needed. This analysis examined associations between day-to-day function, measured by activities of daily living (ADL), and cognition, measured by CLOX scores, among older African American (AA) and non-Hispanic White (nHW) community-dwelling women and men.

METHODS

Design- Cross-sectional.

SETTING

Homes of community-dwelling older adults. Participants- 893 Medicare beneficiaries >65 living in west-central Alabama, without diagnoses of dementia, who were participants in the University of Alabama at Birmingham (UAB) Study of Aging, and who had complete data. Measurements- Physical function was assessed by self-reported ADL difficulty; cognitive function by CLOX, a clock drawing-task. Multivariable, linear regression models were used to examine associations within race/sex specific groups.

RESULTS

After controlling for socio-demographic factors and comorbidities, CLOX1 scores were inversely and significantly correlated with ADL for AA men (β = -0.205, P = 0.003). CLOX2 scores were similarly associated with ADL and IADL for the total group (β = -0.118, P = 0.001, and β = -0.180, P < 0.001, respectively); for ADL, significant associations were seen for AA men and nHW women (β = -0.203, P = 0.004, and β = -0.139, P = 0.02, respectively) and, for IADL, in AA women and men (β = -0.156, P = 0.03, and β = -0.24, P < 0.001, respectively).

CONCLUSION

While African American women reported the highest difficulty with ADLs and IADLs among all race/sex groups, CLOX1 scores were correlated with ADL for AA men only. CLOX1 may have limitations to identify functional disability for older AA women. [Word Count = 234].

Breaking the cycle of functional decline in older dialysis patients

Currently, older adults comprise nearly one-third of prevalent US dialysis patients, and this proportion will increase as the population ages. Older dialysis patients experience greater morbidity and mortality than nondialysis patients of the same age, and in part, it is related to progressive functional decline. Progressive functional decline, characterized by need for assistance with more than 2 activities of daily living, contributes to risk of hospitalization, further functional decline, and subsequent nursing home placement when a patient no longer functions independently at home. Progressive functional decline may appear to be unavoidable for older dialysis patients; however, comprehensive geriatric assessment (CGA) may alleviate the prevalence and severity of functional decline. This editorial summarizes common risk factors of functional decline and introduces CGA as a potentially transformative approach to breaking the cycle of functional decline in older dialysis patients.

Cognitive reserve and executive function: Effect on judgment of health and safety

Individuals with the same neurological conditions do not necessarily manifest the same behavioral presentation, which suggests differences in resilience and vulnerability among individuals, a concept known as cognitive reserve. This study sought to explore the relationship among cognitive reserve, executive functioning, and health and safety judgment among a sample of older adult inpatients in an extended medical care unit at a Veterans Health Administration hospital. We hypothesized that cognitive reserve, as determined by an estimate of premorbid intellectual ability, would act as a protective factor against poor judgment in older adults with executive dysfunction. Participants included 200 Veterans who completed a comprehensive neuropsychological assessment, including measures of health and safety judgment, executive functioning, global cognitive functioning, and premorbid intellectual ability. After controlling for global cognitive functioning, executive functioning abilities did not have an effect on judgment abilities among those with high estimated intellectual ability. However, executive functioning had a significant effect on judgment abilities among those with low estimated intellectual ability. Our results suggest that intact executive functioning is critical for making appropriate health and safety decisions for patients with lower measured intellectual abilities and provide further support for the cognitive reserve model. Clinical implications are also discussed.

The Clock Drawing Test versus Mini-mental Status Examination as a Screening Tool for Dementia: A Clinical Comparison

There is a growing incidence of dementia patients in the community, and with this growth, there is need for rapid, valid, and easily administrable tests for the screening of dementia and mild cognitive impairment in the community. This review looks at the two most commonly used tests in dementia screening, namely, the clock drawing test (CDT) and the mini-mental status examination (MMSE). Both these tests have been used in dementia screening over the past three decades and have been the subject of scrutiny of various studies, reviews, and meta-analysis. Both these tests are analyzed on their ability to assess dementia and screen for it in the community, general practice and general hospital settings. The methods of administration and scoring of each test are discussed, and their advantages and disadvantages are explained. There is also a direct comparison made between the MMSE and CDT in dementia screening. Future research needs with these tests are also elucidated.

Differences in the neural correlates of frontal lobe tests

BACKGROUND

The Executive Interview (EXIT25), the executive clock-drawing task (CLOX1), and the Frontal Assessment Battery (FAB) are used to assess executive function at the bedside. These tests assess distinct psychometric properties. The aim of this study was to examine differences in the neural correlates of the EXIT25, CLOX1, and FAB based on magnetic resonance imaging.

METHODS

Fifty-eight subjects (30 with Alzheimer's disease, 10 with mild cognitive impairment, and 18 healthy controls) participated in this study. Multiple regression analyses were performed to examine the brain regions correlated with the EXIT25, CLOX1, and FAB scores. Age, gender, and years of education were included as covariates. Statistical thresholds were set to uncorrected P-values of 0.001 at the voxel level and 0.05 at the cluster level.

RESULTS

The EXIT25 score correlated inversely with the regional grey matter volume in the left lateral frontal lobe (Brodmann areas 6, 9, 44, and 45). The CLOX1 score correlated positively with the regional grey matter volume in the right orbitofrontal cortex (Brodmann area 11) and the left supramarginal gyrus (Brodmann area 40). The FAB score correlated positively with the regional grey matter volume in the right precentral gyrus (Brodmann area 6). The left lateral frontal lobe (Brodmann area 9) and the right lateral frontal lobe (Brodmann area 46) were identified as common brain regions that showed association with EXIT25, CLOX1, and FAB based only a voxel-level threshold.

CONCLUSIONS

The results of this study suggest that the EXIT25, CLOX1, and FAB may be associated with the distinct neural correlates of the frontal cortex.

Exportation and Validation of Latent Constructs for Dementia Case Finding in a Mexican American Population-based Cohort

BACKGROUND

The latent variable "δ" has been validated as a dementia phenotype. δ can be extracted from Spearman's general intelligence factor "g" in any data set that contains measures of cognition and instrumental activities of daily living (IADL). We used δ composites ("d-scores") to estimate the prevalence of dementia in the Hispanic Established Population for Epidemiological Studies in the Elderly (H-EPESE).

METHOD

δ was constructed from Mini-Mental State Examination, a clock-drawing task (CLOX), and IADL. δ's H-EPESE factor weights were validated in the well-characterized Texas Alzheimer's Research and Care Consortium (TARCC). Optimal thresholds for the discrimination between "Alzheimer's disease" (AD) versus normal controls (NCs) were determined by receiver operating characteristic curve. Those thresholds were used to estimate the prevalence of dementia in H-EPESE.

RESULTS

Each δ homolog fits its source's data well. d-scores were strongly associated with Clinical Dementia Rating scale Sum of Boxes (r = .74-.85, all p < .001], and accurately distinguished AD cases from NCs, in both Mexican Americans (MAs) and non-Hispanic Whites (NHWs) [c = 0.94-0.96]. The TARCC MA threshold estimated the prevalence of dementia at 21.4% in H-EPESE. The NHW threshold estimated the prevalence of dementia at 21.0%.

CONCLUSIONS

It is possible to export δ composites from populations to well-characterized cohorts for validation.

Contribution of auditory P300 test to the diagnosis of mild cognitive impairment in Parkinson's disease

Abnormalities in auditory P300 test have been observed in patients with Parkinson's disease (PD). We aimed to investigate whether or not additional electrophysiological tests assist in making the clinical diagnosis of mild cognitive impairment in Parkinson's disease (PD-MCI), and we evaluated P300 changes in patients with non-demented PD and analyzed the correlation between the cognitive features and P300 changes. Twenty patients with PD who had been diagnosed with mild cognitive impairment (PD-MCI group) according to the Movement Disorder Society (MDS) 2012 PD-MCI level II criteria, 21 patients with PD without cognitive impairment (PD-Normal group), and 20 control subjects (control group) who were neurologically normal were examined by the standard auditory oddball paradigm. The N100, P200, N200, and P300 latencies and N100-P200, P200-N200, and N200-P300 amplitudes were measured and analyzed. P300 latencies recorded from Fz, Cz, and Pz and N200 latency recorded from Fz were significantly longer in the PD-MCI group than in the PD-Normal and the control group (respectively p < 0.001, p = 0.041). P300 amplitude recorded from Fz was significantly lower in PD-MCI group than those in the other groups (p = 0.038). While P300 was obtained in all patients in the PD-Normal and the control group, it was lost in 35% of PD-MCI patients. The results show that P300 provides a diagnostic tool for detecting PDMCI. We suggest that P300 prolongation and loss of P300 potential could be used as supportive parameter in the diagnosis of PD-MCI.

The Letter and Shape Drawing (LSD) test: An efficient and systematised approach to testing of visuospatial function

The automation and systemisation of the next generation of cognitive assessment approaches have the potential to change how clinicians assess and interact with patients. This may be especially pertinent in the case of delirium, as current methods often rely on the subjective opinion of clinicians and specialists, with potential for the condition to be overlooked or misdiagnosed. Currently, one of the most commonly used tests, is the clock-drawing test, which has relatively wide appeal as a cognitive screening instrument due to its clinical utility and psychometric properties. However, there are a number of inconsistencies associated with its use and interpretation. In this paper, we describe a new assessment methodology that we have developed, facilitated by the advances in tablet technology. In trials, our "Letter and Shape Drawing (LSD)" tool, involving both an automated scoring capability and a simpler user interaction, has demonstrated correlation with other conventional cognitive test methods although some optimisation requirements remain.

Use of the Ten-Point Clock Test to Compare Executive Functioning across 24 Months in Patients with Subcortical Vascular Dementia

The Ten-point Clock Test can be used to identify early forms of Alzheimer's disease because it is reliable, well accepted, and easily administered at the bedside. Nevertheless, its clinical role in the detection of early dementia and its correlations with other cognitive processes is still under investigation. Vascular dementia is an uncertain nosological entity, in which unevenly distributed patterns of cognitive deficits comprising slowing of cognitive processing and impairment of executive function occur. The present study assessed how the Clock Test scores correlated with a number of other neuropsychological and functional tests in a sample of 144 patients with vascular dementia, who were followed for a period of 24 mo. At baseline, at 12 mo. and at 24 mo. subjects were administered a battery of tests, including the Mini-Mental State Examination, word fluency, visuospatial skills, an evaluation of hetero- and autotopognosia (knowledge of self), the Proverbs Test, and the Ten-point Clock Test. For these patients scores on the Clock Test correlated significantly with semantic abilities, with abstract reasoning capacities, visuospatial perception, and with right and left recognition.

The Clock Drawing Test: Performance differences between the free-drawn and incomplete-copy versions in patients with MCI and dementia

BACKGROUND

The Clock Drawing Test (CDT) is a brief cognitive screening tool for dementia. Several different presentation formats and scoring methods for the CDT are available in the literature.

OBJECTIVE

In this study we aimed to compare performance on the free-drawn and "incomplete-copy" versions of the CDT using the same short scoring method in Mild Cognitive Impairment (MCI) and dementia patients, and healthy elderly participants.

METHODS

90 participants (controlled for age, sex and education) subdivided into control group (n=20), MCI group (n=30) and dementia group (n=40) (Alzheimer's disease - AD=20; Vascular Dementia - VD=20) were recruited for this study. The participants performed the two CDT versions at different times and a blinded neuropsychologist scored the CDTs using the same scoring system.

RESULTS

The scores on the free-drawn version were significantly lower than the incomplete-copy version for all groups. The dementia group had significantly lower scores on the incomplete-copy version of the CDT than the control group. MCI patients did not differ significantly from the dementia or control groups. Performance on the free-drawn copy differed significantly among all groups.

CONCLUSION

The free-drawn CDT version is more cognitively demanding and sensitive for detecting mild/early cognitive impairment. Further evaluation of the diagnostic value (accuracy) of the free-drawn CDT in Brazilian MCI patients is needed.

Greater than the Sum of Its Parts: δ can be Constructed from Item Level Data

"δ", a latent variable constructed from cognitive performance and functional status measures, can accurately diagnose dementia. The minimal assessment needed is unknown. We have constructed a δ homolog, "dTEXAS", from Telephone Executive Assessment Scale (TEXAS) items, and validated it in a convenience sample of Japanese persons (n = 176). dTEXAS scores correlated strongly with both Instrumental Activities of Daily Living (IADL) (r = -0.86, p <  0.001) and Clinical Dementia Rating Scale (CDR) (r = 0.71, p <  0.001). Constructed independently of their diagnoses, dTEXAS scores accurately distinguished dementia versus controls (area under the receiver operating curve [(AUC; ROC) = 0.92], dementia versus mild cognitive impairment (MCI) (AUC = 0.80) and controls versus MCI (AUC = 0.74). These AUCs are higher than those of multiple observed executive measures, as reported recently by Matsuoka et al., 2014. A dTEXAS score of -0.58 best discriminated between dementia versus controls with 90.1% sensitivity and 80.0% specificity.

δ Scores are Exportable Across Cultural and Linguistic Boundaries

The latent variable "δ", can accurately diagnose dementia. Its generalizability across populations is unknown. We constructed a δ homolog ("dT2J") in data collected by the Texas Alzheimer's Research and Care Consortium (TARCC). From this, we calculated a composite d-score "d". We then tested d's generalizability across random subsets of TARCC participants and to a convenience sample of elderly Japanese persons with normal cognition (NC), mild cognitive impairment (MCI), and dementia (AD) (n = 176). dT2J was indicated by Instrumental Activities of Daily Living and psychometric measures. Embedded in this battery were the Mini-Mental Status Examination (MMSE) and an executive clock-drawing task (CLOX). Only MMSE and CLOX were available in both TARCC and the Japanese cohort. Therefore, a second composite variable, "T2J", was constructed solely from the factor loadings of CLOX and MMSE on d. The diagnostic accuracy of T2J was estimated in the validation sample, the remainder of the TARCC cohort, and in the Japanese sample. The areas under the receiver operating curve (AUC; ROC) for T2J were compared in each sample, and against d in TARCC. The AUCs for T2J were statistically indiscriminable within TARCC, and in Japanese persons. In Japanese persons, AUCs for T2J were 0.97 for the discrimination between AD versus NC, 0.86 for AD versus MCI, and 0.79 for NC versus MCI. The AUCs for T2J in Japanese persons were higher than any individual psychometric measure in that sample. Valid d-score composites can be abstracted from a subset of δ's indicators. Moreover, those composites are exportable across cultural and linguistic boundaries.

A virtual shopping task for the assessment of executive functions: Validity for people with stroke

The importance of assessing executive functions (EF) using ecologically valid assessments has been discussed extensively. Due to the difficulty of carrying out such assessments in real-world settings on a regular basis, virtual reality has been proposed as a technique to provide complex functional tasks under a variety of differing conditions while measuring various aspects of performance and controlling for stimuli. The main goal of this study was to examine the discriminant, construct-convergent and ecological validity of the Adapted Four-Item Shopping Task, an assessment of the Instrumental Activity of Daily Living (IADL) of shopping. Nineteen people with stroke, aged 50-85 years, and 20 age- and gender-matched healthy participants performed the shopping task in both the SeeMe Virtual Interactive Shopping environment and a real shopping environment (the hospital cafeteria) in a counterbalanced order. The shopping task outcomes were compared to clinical measures of EF. The findings provided good initial support for the validity of the Adapted Four-Item Shopping Task as an IADL assessment that requires the use of EF for people with stroke. Further studies should examine this task with a larger sample of people with stroke as well as with other populations who have deficits in EF.

Mapping the clockworks: what does the Clock Drawing Test assess in normal and pathological aging?

The Clock Drawing Test (CDT) is a cognitive screening tool used in clinical and research settings. Despite its role on the assessment of global cognitive functioning, the specific cognitive components required for test performance are still unclear. We aim to assess the role of executive functioning, global cognitive status, visuospatial abilities, and semantic knowledge on Shulman's CDT performance. Fifty-three mild cognitive impairment, 60 Alzheimer's dementia, and 57 normal elderly controls performed the CDT, the Frontal Assessment Battery, the Mini-Mental State Examination, the Stick Design Test, and a naming test (TN-LIN). An ordinal regression assessed specific neuropsychological influences on CDT performance. All the cognitive variables were related to the CDT, accounting for 53% of variance. The strongest association was between the CDT and executive functions, followed by global cognitive status, visuospatial processing, and semantic knowledge. Our result confirms the multidimensional nature of the test and the major role of executive functions on performance.

Combining select neuropsychological assessment with blood-based biomarkers to detect mild Alzheimer's disease: a molecular neuropsychology approach

BACKGROUND

Current work has sought to establish a rapid and cost effective means of screening for Alzheimer's disease (AD) with the most recent findings showing utility of integrating blood-based biomarkers with cognitive measures.

OBJECTIVE

The current project sought to create a combined biomarker-cognitive profile to detect mild AD.

METHODS

Data was analyzed from 266 participants (129 AD cases [Early AD n = 93; Very Early AD n = 36]; 137 controls) enrolled in the Texas Alzheimer's Research and Care Consortium (TARCC). Non-fasting serum samples were collected from each participant and assayed via a multi-plex biomarker assay platform using electrochemiluminescence. Logistic Regression was utilized to detect early AD using two serum biomarkers (TNFα and IL7), demographic information (age), and one neuropsychological measure (Clock 4-point) as predictor variable. Disease severity was determined via Clinical Dementia Rating (CDR) scale global scores.

RESULTS

In the total sample (all levels of CDR scores), the combination of biomarkers, cognitive test score, and demographics yielded the obtained sensitivity (SN) of 0.94, specificity (SP) of 0.90, and an overall accuracy of 0.92. When examining early AD cases (i.e.m CDR = 0.5-1), the biomarker-cognitive profile yielded SN of 0.94, SP of 0.85, and an overall accuracy of 0.91. When restricted to very early AD cases (i.e., CDR = 0.5), the biomarker-cognitive profile yielded SN of 0.97 and SP of 0.72, with an overall accuracy of 0.91.

CONCLUSIONS

The combination of demographics, two biomarkers, and one cognitive test created a biomarker-cognitive profile that was highly accurate in detecting the presence of AD, even in the very early stages.

Combination of the clock drawing test with the physical phenotype of frailty for the prediction of mortality and other adverse outcomes in older community dwellers without dementia

BACKGROUND

Cognitive assessment is thought to increase the ability of the physical phenotype of frailty to identify older persons at a higher risk for adverse outcomes.

OBJECTIVE

Data from a cohort of dementia-free community dwellers were used to investigate whether the clock drawing test (CDT), a quick and easy cognitive screening test, is associated with adverse health outcomes independently of the physical phenotype of frailty.

METHODS

This was a prospective population-based cohort study of 766 dementia-free Italian community dwellers aged 65 years or older. Baseline assessment included the physical phenotype of frailty, 3 different CDT protocols [Sunderland, Shulman, and the clock drawing interpretation scale (CDIS)], and several health confounders. Hazard ratios (HR) and odds ratio (OR) along with their corresponding 95% confidence intervals (CI) from models adjusted for frailty and sociodemographic and health confounders were used to estimate the independent association of the CDT with the 7-year risk of all-cause mortality and the 3-year risk of new and worsening disability, hospitalization, and fractures.

RESULTS

After adjustment for confounders, the Sunderland CDT was significantly associated with all-cause mortality independently of the physical phenotype of frailty (HR = 1.44, 95% CI 1.03-2.01, p = 0.031). However, compared to all nonfrail participants with a normal Sunderland CDT, the HR was 1.57 (95% CI 1.09-2.26, p = 0.016) for those with impairment on the Sunderland CDT only, 2.48 (95% CI 1.46-4.20, p = 0.001) for those with frailty only, and 2.52 (95% CI 1.34-4.77, p = 0.004) for those with both frailty and impairment on the Sunderland CDT. Mortality was unrelated to the CDIS CDT (p = 0.359) and the Shulman CDT (p = 0.281). No statistically significant relationship was found between nonlethal outcomes and any CDT protocol, although trends were found for an association of both the Sunderland CDT (p = 0.118) and the CDIS CDT with worsening disability (p = 0.154).

CONCLUSIONS

In older persons, depending on the scoring system, the CDT may predict the mortality risk independently of the physical phenotype of frailty. However, combining the two measurements does not improve their individual prognostic abilities.

Diagnostic performance of a combination of Mini-Mental State Examination and Clock Drawing Test in detecting Alzheimer's disease

OBJECTIVE

Because of the growing need for quick cognitive screening tests to distinguish Alzheimer's disease (AD) from mild cognitive impairment (MCI), we compare the diagnostic performance of a combination of the Mini-Mental State Examination (MMSE) and a Clock Drawing Test (CDT) to the Japanese version of the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-J cog) in differentiating between patients with AD, patients with MCI, and healthy controls (HC).

METHODS

Data from 146 subjects with AD and 60 subjects with MCI, as well as 49 HC, was retrospectively analyzed. We used logistic regression analysis with diagnosis as dependent variables and scores of the MMSE, the CDT-command, and the CDT-copy as independent variables, and receiver operating characteristic analysis to distinguish patients with AD from patients with MCI or HC.

RESULTS

When patients with AD were compared to HC, the independent predictors of AD were scores on the MMSE and the CDT-command. This combination was more sensitive than the MMSE alone and has nearly the same sensitivity and specificity as the ADAS-J cog. When patients with AD were compared to patients with MCI, the independent predictors were the MMSE and the CDT-copy. This combination was more sensitive and specific than the MMSE alone and was almost as sensitive and specific as the ADAS-J cog.

CONCLUSION

The combination of the MMSE and the CDT could be a powerful screening tool for differentiating between patients with AD, patients with MCI, and HC. Its sensitivity and specificity are comparable to ADAS-J cog, which takes more time.

The relationship between cognitive ability, insight and self-regulatory behaviors: findings from the older driver population

Self-regulation is often promoted as a coping strategy that may allow older drivers to drive safely for longer. Self-regulation depends upon drivers making an accurate assessment of their own ability and having a willingness to practice self-regulatory behaviors to compensate for changes in ability. The current study explored the relationship between older drivers' cognitive ability, their driving confidence and their use of self-regulation. An additional study aim was to explore the relationship between these factors and older drivers' interest in driving programs. Seventy Australian drivers aged 65 years and over completed a questionnaire about their driving and a brief screening measure of cognitive ability (an untimed Clock Drawing Test). While all participants reported high levels of confidence regarding their driving ability, and agreed that they would continue driving in the foreseeable future, a notable proportion performed poorly on the Clock Drawing Test. Compared to older drivers who successfully completed the Clock Drawing Test, those who failed the cognitive test were significantly less likely to report driving self-regulation, and showed significantly less interest in being involved in driving programs. Older drivers with declining cognitive abilities may not be self-regulating their driving. This group also appears to be unlikely to self-refer to driving programs.

Normative performance on the executive clock drawing task in a multi-ethnic bilingual cohort: a project FRONTIER study

BACKGROUND

The executive clock drawing task (CLOX) test is a neuropsychological measure intended to aid in the assessment and detection of dementia in older populations. Few studies have provided normative data for this measure, with even less research available regarding the impact of sociodemographic factors on test scores. This study presents normative data for the CLOX in a sample of English and Spanish-speaking Hispanic and non-Hispanic Whites.

METHODS

The total sample included 445 cognitively healthy older adults seen as part of an ongoing study of rural cognitive aging, project FRONTIER. Unlike previous studies, criteria for "normality" (i.e., unimpaired) for CLOX1 and CLOX2 were based not merely on global impairment, but also on domain-specific impairment of executive functioning on the Executive Interview 25-item Examination and/or Trail Making Test B, or visuospatial/constructional impairment on the Line Orientation and Figure Copy subtests of the Repeatable Battery for the Assessment of Neuropsychological Status, respectively.

RESULTS

Hierarchical regression analyses revealed that CLOX1 scores require adjustment by Age across ethnicities, whereas Education and Gender are necessary stratification markers for CLOX1 performance only in non-Hispanic Whites. None of the demographic variables were valid predictors of CLOX2 performance, negating the need for such adjustments.

CONCLUSION

In addition to being the first study to provide separate normative data for CLOX performance in Hispanic and non-Hispanic White samples, the current study offers a novel approach to defining "normal" by cognitive domain. We also highlight the need to directly examine the impact of sociodemographic factors before applying normative corrections based on factors that have negligible impact on test scores.

Brain activity during the Clock-Drawing Test: multichannel near-infrared spectroscopy study

The Clock-Drawing Test (CDT) is widely used in clinical practice for the screening of dementia. However, neural activity during real clock drawing has not been investigated due to motion artifacts. In the present study, we examined brain activity during real clock drawing using multichannel near-infrared spectroscopy (NIRS). We measured hemoglobin concentration changes in the prefrontal and temporal surface areas during clock drawing using 52-channel NIRS. Data obtained from 37 right-handed healthy volunteers were analyzed. We found significant increases in oxy-Hb in more than 96.2% of the channels (false-discovery rate corrected, p < .025). The time required for CDT performance showed a negative correlation with changes in oxy-Hb in the prefrontal region (r = -.529, p = .002). The mean value for oxy-Hb changes was higher in the left hemisphere in 20 subjects (54%) and in the right hemisphere in 17 subjects (46%). The NIRS/CDT combination is acceptable as a clinical tool, as the method has the advantages of direct measurement of cortical activation with high temporal resolution. Our results confirm the aspects of the CDT involving the frontal-lobe battery.

Normative performance on an executive clock drawing task (CLOX) in a community-dwelling sample of older adults

The CLOX is a clock drawing test used to screen for cognitive impairment in older adults, but there is limited normative data for this measure. This study presents normative data for the CLOX derived from a diverse sample of 585 community-dwelling older adults with complete cognitive data at baseline and 4-year follow-up. Participants with evidence of baseline impairment or substantial 4-year decline on the Mini-Mental State Examination were excluded from the normative sample. Spontaneous clock drawing (CLOX1) and copy (CLOX2) performances were stratified by age group and reading ability from the Wide Range Achievement Test, 3rd edition (WRAT-3). Lowest mean CLOX scores were observed for the oldest age group (75+ years old) with the lowest WRAT-3 reading scores. For all groups, average scores were higher for CLOX2 than CLOX1. These normative data may be helpful to clinicians and researchers for interpreting CLOX performance in older adults with diverse levels of reading ability.

Screening and case-finding tools for the detection of dementia. Part II: evidence-based meta-analysis of single-domain tests

AIM

To evaluate the diagnostic validity of single-domain cognitive tests for detecting dementia. These methods were defined as those that focus mainly on one domain of cognitive function such as orientation, memory, or executive function.

METHODS

A meta-analysis of robust studies was conducted. There were 15 categories of single-domain methods assessed in 45 analyses, including 27 performed head-to-head against the Mini-Mental State Examination (MMSE). Thirteen studies took place in community settings, 9 in primary care, and 23 in specialist settings.

RESULTS

In community settings, single-domain cognitive tests helped detect 64.2% of all dementias. In this setting, specificity (Sp) was 84.9%, positive predictive value (PPV) was 57.1%, and negative predictive value (NPV) was 88.3%. This was significantly less accurate than the MMSE itself. The optimal individual method was the memory impairment screen (MIS). In primary care, the sensitivity (Se) and specificity of single-domain tests were 69.5% and 82.5%, respectively. The PPV and NPV were 36.5% and 95.8%. Considered together, these methods were less specific but equally sensitive as the MMSE when applied in primary care. Here, the most successful methods were the selective reminding test (SRT) and clock drawing test, the latter having data from independent samples. In specialist settings, single-domain methods had a Se of 76.6%, a Sp of 81.9%, a PPV 80.8%, and a NPV 74.9%. This represented almost equivalent accuracy to the MMSE. The optimal method for specialist settings (based on accuracy alone) was the memory alteration test.

CONCLUSION

Brief single-domain methods offer diagnostic performance for detection of dementia that is surprisingly close to that offered by cognitive batteries such as the MMSE. As a method of screening or as part of a diagnostic algorithm, brief single-domain tests may be an efficient first step in identifying cognitive impairment.

Numeracy skills in CKD: correlates and outcomes

BACKGROUND AND OBJECTIVES

Healthcare providers communicate the risks and benefits of treatments using frequencies, percentages, or proportions. However, many patients lack the numerical skills needed to interpret this information accurately to make informed choices.

DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS

We assessed numeracy, the capacity to use and comprehend numbers, in a prospective cohort study of 187 patients with stage 4 to 5 chronic kidney disease or ESRD. Patients completed a three-item numeracy test and were assessed for global mental status, cognitive function, type of hemodialysis access, and kidney transplant use. We examined the association of numeracy with healthcare use and other cognitive and sociodemographic variables.

RESULTS

Over 50% of patients answered one or fewer numeracy questions correctly. Although African Americans (P = 0.0001), women (P = 0.05), and the unemployed (P = 0.0004) demonstrated lower numeracy skills, numeracy deficits were prevalent in every subgroup. In analyses adjusted for demographics and length of follow-up, higher numeracy was significantly associated with receipt of a transplant or active waiting list status. Numeracy was not associated with dialysis modality or hemodialysis vascular access.

CONCLUSION

Similar to prior findings in the general population, these findings indicate that poor numeracy skills are very common in patients with advanced chronic kidney disease and end-stage renal disease. Additional research is needed to further explore whether poor numeracy is a barrier to receipt of a kidney transplant. Clinicians caring for patients with kidney disease should consider using tools to enhance communication and overcome limited numeracy skills.

Rasch analysis of the Executive Interview (The EXIT-25) and introduction of an abridged version (The Quick EXIT)

OBJECTIVES

To evaluate the psychometric properties of the Executive Interview (EXIT-25) and to propose modifications that will improve those properties.

DESIGN

Rasch analysis of existing datasets contributed by 3 prior projects, all of which examined criterion-related validity of the EXIT-25.

SETTING

A large, urban, academic free-standing rehabilitation facility.

PARTICIPANTS

The sample of 147 was comprised of 109 adults diagnosed with stroke evaluated during inpatient rehabilitation and 38 adults with traumatic brain injury evaluated during inpatient (n=11) or outpatient rehabilitation (n=27).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The EXIT-25, Repeatable Battery for the Assessment of Neuropsychological Status, and Trails A and B.

RESULTS

Eleven of the 25 items correlated weakly with the total measure and misfit the rating scale model. Deleting these 11 items improved the internal consistency of the remaining 14 items and enhanced the measure's criterion-related validity.

CONCLUSIONS

The EXIT-25 can be reduced from 25 to 14 items without reducing internal consistency. Convergent validity of the abbreviated measure is supported by moderate-size correlations with standard measures of cognitive deficits.

Clock drawing test ratings by dementia specialists: interrater reliability and diagnostic accuracy

The authors conducted a study of clock drawing test scoring by dementia specialists to determine interrater reliability and diagnostic accuracy. The authors randomly assigned 25 clocks from each of six predetermined groups based on consensus diagnosis (cognitive comparison subjects, subjects with a memory complaint but with normal neuropsychological testing, subjects with probable and possible mild cognitive impairment, and subjects with possible and probable Alzheimer's disease) to dementia specialists for blinded scoring using a binary yes/no impairment system and a 0-10 scale as subjectively determined by each individual clinician rater. The authors collapsed the six groups into three (comparison subjects, mild cognitive impairment patients, and Alzheimer's disease patients) and analyzed interrater reliability, sensitivity, and specificity for consensus diagnosis of mild cognitive impairment and Alzheimer's disease. The authors found excellent interrater reliability, sensitivity, and specificity for predicting consensus diagnosis. The 0-10 clock drawing test rating scale was more predictive of consensus diagnosis than the binary impairment scale. Based on rating systems, clock drawing test scoring by dementia clinicians had excellent interrater reliability and sensitivity for differentiating the mild Alzheimer's disease subjects from comparison subjects.

Utilization of Frontal Assessment Battery and Executive Interview 25 in assessing for dysexecutive syndrome and its association with diabetes self-care in elderly patients with type 2 diabetes mellitus

AIMS

Executive function (EF) comprises a set of cognitive skills that controls the execution of complex activities. In the context of diabetes, this may include patients' self-monitoring and daily management of their condition. We compared two different measures of EF in a population of elderly patients with type 2 diabetes mellitus (T2DM) and studied its relationship with diabetes self-care.

METHODS

Fifty patients (34 males) had EF assessed using Frontal Assessment Battery (FAB) and Executive Interview 25 (EXIT25). Diabetes self-care was assessed using the Summary of Diabetes Self-Care Activities (SDSCA) scale. Haemoglobin A1c (HbA1c), lipid levels, blood pressure and diabetes duration were recorded.

RESULTS

The mean age of the patients was 67.0+/-7.5 years and mean duration of diabetes was 8.1+/-6.4 years. Mean HbA1c was 7.0+/-1.2%, and mean fasting plasma glucose, cholesterol and LDL-C were 7.0+/-1.7mM, 4.0+/-0.9mM and 2.1+/-0.7mM respectively. Mean EXIT25 score was 9.5+/-4.6 in the range of normal EF (14% had EXIT25 score>15, indicating impaired EF). Mean FAB score was 13.7+/-3.3 (48% having scores<15, indicating impaired EF), suggesting a degree of dysexecutive syndrome involving frontal lobe functions. EXIT25 score was inversely correlated with SDSCA (r=-0.3, p<0.05) but no significant correlation between FAB and SDSCA or HbA1c, diabetes duration, lipid levels and blood pressure with EXIT25, FAB or SDCSA was found.

CONCLUSION

A substantial proportion of elderly patients with T2DM may have dysexecutive syndrome and impairment in EF may impact on self-care in this group.

Validation and comparison of two frailty indexes: The MOBILIZE Boston Study

OBJECTIVES

To validate two established frailty indexes and compare their ability to predict adverse outcomes in a diverse, elderly, community-dwelling sample of men and women.

DESIGN

Prospective observational study.

SETTING

A diverse defined geographic area of Boston.

PARTICIPANTS

Seven hundred sixty-five community-dwelling participants in the Maintenance of Balance, Independent Living, Intellect, and Zest in the Elderly Boston Study.

MEASUREMENTS

Two published frailty indexes, recurrent falls, disability, overnight hospitalization, emergency department (ED) visits, chronic medical conditions, self-reported health, physical function, cognitive ability (including executive function), and depression. One index was developed from the Study of Osteoporotic Fractures (SOF) and the other from the Cardiovascular Health Study (CHS).

RESULTS

The SOF frailty index classified 77.1% as robust, 18.7% as prefrail, and 4.2% as frail. The CHS frailty index classified 51.2% as robust, 38.8% as prefrail, and 10.0% as frail. Both frailty indexes (SOF; CHS) were similar in their ability to predict key geriatric outcomes such as recurrent falls (hazard ratio (HR)(frail)=2.2, 95% confidence interval (CI)=1.2-4.0; HR(frail)=1.9, 95% CI=1.2-3.1), overnight hospitalization (odds ratio (OR)(frail)=3.5, 95% CI=1.5-8.0; OR(frail)=4.4, 95% CI=2.4-8.2), ED visits (OR(frail)=3.5, 95% CI=1.4,8.8; OR(frail)=3.1, 95% CI=1.6-5.9), and disability (OR(frail)=5.4, 95% CI=2.3-12.3; OR(frail)=7.7, 95% CI=4.0-14.7), as well as chronic medical conditions, physical function, cognitive ability, and depression.

CONCLUSION

Two established frailty indexes were validated using an independent elderly sample of diverse men and women; both indexes were good at distinguishing geriatric conditions and predicting recurrent falls, overnight hospitalization, and ED visits according to level of frailty. Although both indexes are good measures of frailty, the simpler SOF index may be easier and more practical in a clinical setting.

The Clock Drawing Test: A review of its accuracy in screening for dementia

The Clock Drawing Test (CDT) is a simple neuropsychometric instrument that can be easily applied to assess several cognitive functions. Over the past 20 years, the CDT has aroused considerable interest in its role for the early screening of cognitive impairment, especially in dementia. Although the CDT is considered an accurate test for dementia screening, recent studies including comparisons with structured batteries such as the CAMCOG have shown mixed results.

Objectives

To investigate the importance of the CDT compared to other commonly used tests, in the diagnosis of dementia in the elderly; (2) to evaluate the reliability and correlation between available CDT scoring scales from recent studies.

Methods

A systematic search in the literature was conducted in September 2008 for studies comparing CDT scoring systems and comparing the CDT with neuropsychiatric batteries.

Results

Twelve studies were selected for analyses. Seven of these studies compared CDT scoring scales while five compared the CDT against the CAMCOG and the MMSE. Eight studies found good correlation and reliability between the scales and the other tests.

Conclusion

Despite the mixed results in these studies, the CDT appears to be a good screening test for dementia.

Errorless practice as a possible adjuvant to donepezil in Alzheimer's disease

Six individuals with probable Alzheimer's disease (AD) participated in a phase 1 study employing a repeated measures, parallel baseline design testing the hypothesis that error-free experience during word production practice combined with an acetyl cholinesterase inhibitor would improve confrontation naming ability. While acetyl cholinesterase inhibitors are safe and delay cognition decline associated with AD, improvement over baseline cognition is less evident; clinically significant cognitive deficits persist and progress. Both animal and clinical research strongly implicate acetylcholine in learning, a form of neuroplasticity. In clinical practice, however, people with AD are given cholinergic medications without concomitant systematic/targeted retraining. In this study six participants with probable AD and taking donepezil participated in targeted word production practice using an errorless learning strategy. Results showed that combining behavioral enrichment training and an acetyl cholinesterase inhibitor resulted in significant improvements in verbal confrontation naming of trained items for three of six participants. Differences in baseline dementia severity, living conditions, and medications may have influenced the training response. Detection of substantial treatment effects in 50% of subjects suggests further language treatment studies in AD in combination with an acetyl cholinesterase inhibitor are warranted and provide useful information on inclusion/exclusion criteria for use in subsequent studies.

Can an 18-point clock-drawing scoring system predict dementia in elderly individuals with mild cognitive impairment?

The purpose of this study was to develop a clock-drawing scoring system better suited to detecting possible early markers of dementia in individuals with mild cognitive impairment (MCI). We modified the scoring system of Freedman et al. (1994), in which the major components are integrity of the circle, placement and size of the hands, and placement and sequence of the numbers. We rescored the clock-drawing test using a novel 18-point scoring system, which emphasizes hand elements-number of hands, direction indicated, and size differences. We retrospectively assessed 123 individuals (ages 58-88 years) selected from the Memory Clinic at the Jewish General Hospital in Montreal. These consisted of 21 normal elderly individuals (NORM group), 41 participants with mild cognitive impairment who did not develop dementia on follow-up visits (MCI-NP), 41 participants with mild cognitive impairment who became demented after a 48-month follow-up (MCI-D), and 20 participants diagnosed with Alzheimer's disease (AD). On the 18-point system, the MCI-NP and the MCI-D did not show any difference on overall total score (p = .166), However, using Pearson chi-squares to examine the within-categories effects comparing the mildly cognitively impaired groups (MCI-NP and MCI-D), there were three significant hand items that appear to be possible early markers of progression to dementia. The clock has two hands (p = .043), hour hand is towards correct number (p = .023), and size difference of the hands is respected (p = .004), all showed significant differences between progressors and nonprogressors. The 18-point clock-drawing scoring system may have advantages in better indicating MCI individuals more likely to progress to dementia.

Asymmetric insular function predicts positional blood pressure in nondemented elderly

Forty percent of nondemented octogenarians have Braak stages consistent with insular involvement, and may be at risk for "age-related" autonomic dysfunction. The authors examined the association between insular resting cerebral blood flow (rCBF) and cardiovascular functions in 29 nondemented elderly subjects who were highly screened to exclude comorbid cardiovascular disease. Mean insular rCBF was significantly higher on the right than left. However, 35.4% of participants had left dominant rCBF (a high-risk group). Right insular rCBF was significantly lower in the high-risk group. This subset had significantly increased positional drops in systolic blood pressure. While these data cannot address Alzheimer's disease as the specific cause, this possibility is being investigated in other cohorts.

The Clock Drawing Test: performance among elderly with low educational level

OBJECTIVE: To compare the accuracy of four scales, and to determine the inter-rater reliability and the influence of schooling on Clock Drawing Test performance in screening for dementia in elderly with low educational level. METHOD: Design: Criterion validation, concurrent type. Setting: Outpatient unit of Universidade do Estado do Rio de Janeiro Hospital, Brazil. Participants: A total of 306 individuals (> 65 years) were assessed by a geriatrician and a neuropsychologist using functional and cognitive instruments. The diagnosis of dementia was established by consensus in a meeting between these professionals. Four different researchers blinded as to the cognitive status of the patients scored the Clock Drawing Test using Shulman's, Sunderland's, Manos', and Wolf-Klein's methods; and a fifth researcher assessed Manos' method for an inter-rater reliability study. RESULTS: The data of 211 individuals (≤ 4 years of schooling) were analyzed. The sensitivity and specificity of the four methods were similar (about 65%). The inter-rater reliability of Manos' method was excellent (ICC = 0.944). The areas under the ROC curves were small (0.657 to 0.681), and the differences between them were not statistically significant. CONCLUSIONS: The Clock Drawing Test is a reliable but not valid test to screen for dementia in older outpatients with 4 or less years of formal schooling.

Clock-drawing potentially mediates the effect of depression on mortality: replication in three cohorts

OBJECTIVE

Previously studies have associated visuospatial tasks, particularly 'clock-drawing', with mortality. We sought to determine whether clock-drawing also mediates the association between depressive symptoms and mortality.

PARTICIPANTS

Non-institutionalized Hispanic and non-Hispanic White elderly volunteers.

MEASUREMENTS

Survival curves were generated as a function of baseline depressive symptom ratings. Significant models were adjusted for CLOX performance. CLOX is divided into CLOX1, a measure of executive control, and CLOX2, a measure of visuospatial skills.

DESIGN

Retrospective analysis of three longitudinal cohorts.

RESULTS

CLOX2 and depressive symptoms were both associated with mortality in unadjusted models. CLOX2 predicted survival independently of CLOX1 in all three cohorts. CLOX2 also attenuated, and/or mediated the association between depressive symptoms and mortality. These results withstood adjustment for age and education in all three cohorts.

CONCLUSION

Regardless of the sample examined, or the measure of depressive symptoms applied, the association between depressive symptoms and mortality appears to be at least partially mediated by visuospatial skills. This finding supports our hypothesis that right hemisphere structural brain disease, particularly that involving the insula, may mediate depression's effects on mortality.

The MOBILIZE Boston Study: design and methods of a prospective cohort study of novel risk factors for falls in an older population

Background

Falls are the sixth leading cause of death in elderly people in the U.S. Despite progress in understanding risk factors for falls, many suspected risk factors have not been adequately studied. Putative risk factors for falls such as pain, reductions in cerebral blood flow, somatosensory deficits, and foot disorders are poorly understood, in part because they pose measurement challenges, particularly for large observational studies.

Methods

The MOBILIZE Boston Study (MBS), an NIA-funded Program Project, is a prospective cohort study of a unique set of risk factors for falls in seniors in the Boston area. Using a door-to-door population-based recruitment, we have enrolled 765 persons aged 70 and older. The baseline assessment was conducted in 2 segments: a 3-hour home interview followed within 4 weeks by a 3-hour clinic examination. Measures included pain, cerebral hemodynamics, and foot disorders as well as established fall risk factors. For the falls follow-up, participants return fall calendar postcards to the research center at the end of each month. Reports of falls are followed-up with a telephone interview to assess circumstances and consequences of each fall. A second assessment is performed 18 months following baseline.

Results

Of the 2382 who met all eligibility criteria at the door, 1616 (67.8%) agreed to participate and were referred to the research center for further screening. The primary reason for ineligibility was inability to communicate in English. Results from the first 600 participants showed that participants are largely representative of seniors in the Boston area in terms of age, sex, race and Hispanic ethnicity. The average age of study participants was 77.9 years (s.d. 5.5) and nearly two-thirds were women. The study cohort was 78% white and 17% black. Many participants (39%) reported having fallen at least once in the year before baseline.

Conclusion

Our results demonstrate the feasibility of conducting comprehensive assessments, including rigorous physiologic measurements, in a diverse population of older adults to study non-traditional risk factors for falls and disability. The MBS will provide an important new data resource for examining novel risk factors for falls and mobility problems in the older population.

Time that tells: critical clock-drawing errors for dementia screening

BACKGROUND

Clock-drawing tests are popular components of dementia screens but no single scoring system has been universally accepted. We sought to identify an optimal subset of clock errors for dementia screening and compare them with three other systems representative of the existing wide variations in approach (Shulman, Mendez, Wolf-Klein), as well as with the CDT system used in the Mini-Cog, which combines clock drawing with delayed recall.

METHODS

The clock drawings of an ethnolinguistically and educationally diverse sample (N = 536) were analyzed for the association of 24 different errors with the presence and severity of dementia defined by independent research criteria. The final sample included 364 subjects with > or = 5 years of education, as preliminary examination suggested different error patterns in subjects with 0-4 years of education and inadequate numbers of normal controls for reliable analysis.

RESULTS

Eleven of 24 errors were significantly associated with dementia in subjects with > or = 5 years of education, and six were combined to identify dementia with 88% specificity and 71% sensitivity: inaccurate time setting, no hands, missing numbers, number substitutions or repetitions, or refusal to attempt clock drawing. Time setting was the most prevalent error at all dementia stages, refusal occurred only in moderate and severe dementia; and ethnicity and language of administration had no effect. All critical errors increased in frequency with dementia stage. This simplified scoring system had much better specificity than two other systems (88% vs 39% for Mendez's system - 63% for Shulman's) and much better sensitivity than Wolf-Klein's (71% vs 51%). Stepwise logistic regression found the simplified system to be more strongly predictive of dementia than the three other CDT systems of dementia. Substituting the new CDT algorithm for that used in the original CDT Mini-Cog improved the Mini-Cog's specificity from 89 to 93% with minimal change in sensitivity.

CONCLUSIONS

Only six errors need be assessed to capture most of the power of clock drawing to discriminate between people with dementia and normal subjects, and improves specificity over older systems in subjects with > or = 5 years of education. These errors require minimal conceptual classification and are easily detected and scored by non-specialists.