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Aims: To determine whether the pentagon copying test (PCT) and the clock drawing test (CDT) are associated with nursing home admission or survival in dementia with Lewy bodies (DLB). Methods: The PCT and/or the CDT were retrospectively collected from 103 clinically diagnosed probable DLB patients at a university medical center and general hospital. Patients with high versus low scores on these tests were compared. Results: Kaplan-Meier analysis showed that patients with a low score on the PCT had a shorter time to nursing home admission than patients with a high score (log-rank χ2 = 6.1, p = 0.01). Patients with a low score on the PCT or the CDT had a shorter survival than patients with a high score (log-rank χ2 = 5.4, p = 0.02, and log-rank χ2 = 11.2, p < 0.001, respectively). Cox regression analyses showed the same associations with an HR of 2.2 (95% CI 1.2–4.1) for the PCT and an HR of 2.9 (95% CI 1.6–5.4) for the CDT. Conclusion: The PCT and the CDT may function as prognostic markers in DLB. This finding is clinically relevant as these tests can be applied easily in the clinical setting and can provide valuable prognostic information. Furthermore, it may improve disease management and patient selection for research purposes. [ABSTRACT FROM AUTHOR]

Background/Aims: Clock drawing (CD) seems to be impaired quite early in the process of cognitive decline in Parkinson's disease (PD). Methods: We assessed performance on the CD test (CDT), clock setting test (CST) and clock reading test (CRT) in 32 elderly healthy controls, 41 patients with PD, 23 patients with amnestic mild cognitive impairment (aMCI) and 40 patients with Alzheimer's dementia (AD). Our focus was on comparing the performance of PD and aMCI/AD patients in relation to their global cognitive states (operationalized by the Mini Mental Status Examination). We also analyzed qualitative differences in errors of drawing, setting and reading clocks. Results: We found that performance in CDT, but not in the CST or CRT, was impaired earlier in PD than in aMCI/AD. Incorrect placement of the minute hand was the most prominent error in both patient groups. We found no specific influence of visuospatial dysfunction in PD on clock drawing. Conclusion: Our findings suggest that executive function related to retrieval of semantic memory about the minute hand is compromised early in PD. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: Conversion rates to dementia are known to be high for patients with mild cognitive impairment (MCI), but the diagnosis of MCI is very time-consuming. Since the Clock Drawing Test (CDT) is quick to administer, it will be of interest to compare the predictive validity of the CDT and of an MCI diagnosis for the diagnosis of dementia. Methods: In a sample of 384 individuals, CDT scores and the presence of MCI were assessed at baseline and then compared between individuals with an incident dementia diagnosis at follow-up and those without. Multivariate analyses, receiver operating characteristic analyses and values of sensitivity and specificity of the CDT were performed. Results: Individuals with incident dementia had significantly higher CDT scores at baseline than those without dementia. CDT was a significant predictor of incident dementia after adjusting for other factors. CDT reached a sensitivity of 68% and specificity of 65%. The area under the receiver operating characteristic curve of CDT was 0.70 and therefore slightly lower than for MCI diagnosis (0.78). Conclusions: Because of the only slightly lower predictive value of the CDT, its quick application and scoring compared to the MCI concept applied, it will be worthwhile to improve the CDT scoring system in order to increase the predictive validity in dementia. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: CLOX, a clock drawing test protocol uniquely sensitive to impairment of executive functions, has been proposed as a screening tool for mild cognitive impairment (MCI), but data about its diagnostic efficiency are lacking. Methods: There are data for 196 subjects, age ≥60 years, referred to a memory clinic for cognitive complaints. After extensive neuropsychological testing, 64 were diagnosed as cognitively normal and 132 with MCI. Results: At standard cutoffs, both CLOX subtests had a fair specificity (CLOX1 72%, CLOX2 92%) but unacceptably low values of sensitivity (CLOX1 54%, CLOX2 28%) and likelihood ratio (CLOX1 1.91, CLOX2 3.59) for MCI. The use of different cutoffs or the combination of CLOX with the Mini-Mental State Examination (MMSE) did not statistically increase diagnostic efficiency. Conclusion: CLOX, either alone or in combination with MMSE, is not a useful screening test for MCI in a clinical setting. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Individuals with mild cognitive impairment (MCI) are at high risk of developing dementia and are a target group for preventive interventions. Therefore, research aims at diagnosing MCI at an early stage with short, simple and easily administrable screening tests. Due to the fact that the Clock Drawing Test (CDT) is widely used to screen for dementia, it is questionable whether it is suited to screen for MCI. Methods: 3,198 primary care patients aged 75+ were divided into two groups according to their cognitive status, assessed by comprehensive neuropsychological testing: individuals without MCI and individuals with MCI. The CDT scores, evaluated by the scoring system of Sunderland et al. [J Am Geriatr Soc 1989;37:725–729], of both groups were compared. Multivariate analyses were calculated and the sensitivity and specificity of the CDT to screen for MCI were reported. Results: Significant differences were found for CDT results: MCI patients obtained worse results than cognitively unimpaired subjects. CDT has a significant impact on the diagnosis of MCI. However, sensitivity and specificity as well as receiver operating characteristic analyses are not adequate, meaning that the CDT could not be named as an exact screening tool. Limitations: Applying different CDT versions of administration and scoring could yield different results. Conclusions: CDT does not achieve the quality to screen individuals for MCI. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: The Clock Drawing Test (CDT) is used in clinical practice for the screening of cognitive disorders. This systematic review aims to present and discuss the CDT scoring methods available in the literature, in order to find differences in administration and utility of the CDT. Methods: A literature search was carried out in Medline (1966 to June 2008), Psychinfo (1967 to June 2008) and EMBASE (1980 to June 2008). Results: All studies showed good interrater and test-retest reliabilities. The correlation with other standard screening tests was statistically significant in most studies, but the results were influenced by age, education and language. In studies that included patients with mild or questionable dementia, the CDT had a low sensitivity and variable specificity. Conclusion: The CDT has the characteristics of a good screening method for moderate and severe dementia. However, the scoring method used and potential confounders need to be taken into consideration. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aim: This study aimed to identify the functional neuroanatomical correlates of impaired clock drawing test (CDT) performance in patients with Alzheimer’s disease (AD). Method: The CDT was administered to 71 patients with AD, and regional cerebral glucose metabolism (rCMglc) was measured by positron emission tomography (PET). Correlations between CDT scores and rCMglc were examined on a voxel-by-voxel basis. Results: Significant positive correlations were found between CDT performance and rCMglc in the right inferior parietal lobule and right posterior cingulate cortex. Conclusion: These results provide the first PET evidence that poor CDT performance in patients with AD is closely related to the functional decline in the right hemisphere, especially the right parietal cortex. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aim: The aim was to identify subjects with incipient Alzheimer’s disease (AD) among patients with mild cognitive impairment (MCI) using brief cognitive tests. Methods: A total of 147 MCI patients were followed for 4–6 years and the incidence of AD was 11.6%/year. At baseline, the cube copying test, clock drawing test, MMSE and measurements of regional cerebral blood flow (rCBF) and cerebrospinal fluid (CSF) β-amyloid1–42 (Aβ42) were performed. Results: The cube copying test, but not the clock drawing test, could predict AD among MCI patients with an area under the receiver operating characteristic curve of 0.64 (p < 0.01). The relative risk for future AD was increased in MCI subjects with impaired cube copying test (sex- and age-adjusted hazard ratio = 1.8, p < 0.05) and the incidence of AD was 18.2% in this subgroup. Combining the cube copying test with either rCBF or CSF Aβ42 had additive effects on the risk assessment for future development of AD. MCI patients achieving high scores on both MMSE and cube copying test had a very low risk of developing AD (incidence of AD = 1.6%). Conclusion: In conclusion, combinations of the cube copying test with MMSE, rCBF and CSF Aβ42 measurements can identify subgroups of MCI subjects with either substantially reduced or increased risk for future development of AD. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: Clock Drawing Tests are commonly used for cognitive screening, but their clinical utility has not yet been studied in Chinese Singaporeans. We examined the usefulness of a Clock Drawing Test, CLOX, in detecting dementia in our population and explored its performance in the dementia subtypes, Alzheimer’s disease (AD), and the vascular composite group (VCG) of AD with cerebrovascular disease and vascular dementia. Method: CLOX was administered to 73 subjects (49.3%) with dementia and 75 healthy controls (50.7%). Receiver operating characteristic analysis determined the diagnostic accuracy and optimal cut-off scores, stratified by education. Analysis of Variance was used to compare CLOX scores between AD and VCG. Results: The diagnostic accuracy (area under the curve) was 84 and 85% for CLOX1 and CLOX2, respectively. Cut-offs at 10 for CLOX1 and 12 for CLOX2 yielded sensitivities of 75.3 and 75%, and specificities of 76 and 80%, respectively. The mean CLOX1 but not CLOX2 scores for AD (8.1) and VCG (5.5) remained significantly different (p = 0.002) after adjustment for the covariates age, gender, education, MMSE and dementia stage. Conclusion: Our results support CLOX as a valid cognitive screen in Singaporean Chinese with adequate psychometric properties. In addition, CLOX may aid as an adjunct in differentiating AD from dementia with a vascular element, e.g. AD with cerebrovascular disease and vascular dementia. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Aims: To investigate the influences of vascular lesions detected by MRI, lesions involving the cortical cholinergic pathways and hippocampal thickness on therapeutic responsiveness to donepezil in patients with Alzheimer’s disease (AD). Methods: The study cohort contained 67 patients with probable AD. We used the revised Hasegawa Dementia Rating (HDS-R) and the Clock Drawing Test (CDT) to evaluate drug efficacy for 24 months. The Cholinergic Pathways Hyperintensities Scale (CHIPS), a newly developed visual scale, was used to semiquantify lesions on the cholinergic pathways. Results: Over the 24-month period, the results of the CDT showed more apparent and constant association with white matter hyperintensities (WMH) and lesions on the cholinergic pathways than the HDS-R. WMH may enhance, while lesions on the cholinergic pathways may attenuate sensitivity to donepezil treatment when judged by the CDT. No apparent association between the thicknesses of hippocampi with baseline cognition or therapeutic responsiveness to donepezil was found. Conclusion: Donepezil may be more efficacious when further executive dysfunction caused by WMH is added to AD dementia and less so when cholinergic reserves are further impinged upon by lesions involving the cortical cholinergic pathways. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

To identify the neural correlates for impaired performance on the clock drawing test (CDT) in patients with Alzheimer’s disease (AD), we examined the relationship between the CDT performances and the regional cerebral blood flow (rCBF) in 100 AD patients. The patients were equally divided into a mildly impaired CDT group, a severely impaired CDT group, and two normal CDT groups, with age and dementia severity matched. Between-group comparisons revealed that rCBF reduction in the posterolateral region of the left temporal lobe was consistently associated with mild to severe impairment of the CDT in AD. Correlation analysis also showed that the rCBF in the left posterolateral temporal cortex was linearly correlated with CDT performance. The CDT scores in AD were significantly improved for the copy condition relative to the drawing-to-command condition. These findings suggest that CDT performance has a close relationship with the left posterior temporal function, and that semantic memory deficit may at least partly contribute to impaired CDT performance in AD. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]