Clinical usefulness of the clock drawing test applying rasch analysis in predicting of cognitive impairment

Diagnostic accuracy of cognitive screening tools validated for older adults in Iran: a systematic review and meta-analysis

BACKGROUND

This systematic review aims to comprehensively assess the diagnostic accuracy of cognitive screening tools validated for older adults in Iran, providing evidence-based recommendations for clinicians and researchers.

METHODS

A comprehensive search in March 2023 across Web of Science, PubMed, Scopus, ScienceDirect, SID, IranMedex, and IranDoc, enhanced by hand-searching references and Google Scholar, identified cross-sectional studies on cognitive screening in Iranian seniors. We assessed diagnostic accuracy, cognitive domains, and test strengths and weaknesses. A bivariate random-effects meta-analysis provided summary estimates and 95% confidence intervals, illustrated in forest plots.

RESULTS

Our review, derived from an initial screening of 38 articles, focused on 17 studies involving 14 cognitive screening tools and participant counts from 60 to 350, mostly from specialized clinics. The MMSE was the only tool examined in at least three studies, prompting a meta-analysis revealing its sensitivity at 0.89 and specificity at 0.77 for dementia detection, albeit amidst significant heterogeneity (I^2 > 80%). ACE-III demonstrated the highest diagnostic accuracy for MCI and dementia, while MoCA's performance was deemed adequate for MCI and excellent for dementia. High bias risk in studies limits interpretation.

CONCLUSION

This review identifies key cognitive tools for dementia and MCI in Iranian older adults, tailored to educational levels for use in primary and specialized care. It emphasizes the need for further validation to enhance diagnostic precision across diverse settings, within a concise framework prioritizing brevity and accuracy for clinical applicability.

Decreased Plasma Level of Lipoprotein Lipase Predicted Verbal Disfluency in Chinese Type 2 Diabetes Mellitus Patients with Early Cognitive Deficits

BACKGROUND

Lipoprotein Lipase (LPL) is the rate-limiting enzyme catalyzing the hydrolysis of triglycerides and contributes to the amyloid-β formation, which shows promise as a pathological factor of cognitive decline in Type 2 Diabetes Mellitus (T2DM). This study aimed to investigate the pathogenetic roles of LPL and rs328 polymorphism in Mild Cognitive Impairment (MCI) in patients with T2DM.

METHODS

Chinese patients with T2DM were recruited and divided into two groups based on the Montreal Cognitive Assessment score. Demographic data were collected, LPL was measured and neuropsychological test results were examined.

RESULTS

Seventy-nine patients with diabetes and MCI had significantly decreased plasma LPL levels (p = 0.007) when compared with health-cognition controls (n = 91). Correlation analysis revealed that LPL was positively correlated with clock drawing test (r = 0.158, p = 0.043) and logical memory test (r = 0.162, p = 0.037), while lipoprotein a (r = -0.214, p = 0.006) was inversely associated with LPL. Logistic regression analysis further demonstrated that LPL concentration was an independent factor for diabetic MCI (p = 0.036). No significant differences were observed in the distributions of rs328 variants between patients with MCI and the controls. Moreover, no remarkable association was found among plasma LPL levels, cognitive performances, and lipid levels between the genotypic subgroups. The trail making test A was increased in the GC group when compared with the CC genotype in the control group.

CONCLUSION

Decreased plasma level of LPL could probably predict early cognitive deficits, especially verbal disfluency.

Measuring global functioning in older adults with cognitive impairments using the Rasch model

Background

Cognitive and functional measures are often measured and interpreted separately during the clinical evaluation of patients with cognitive impairment. This can sometimes lead to a challenging interpretation when measures do not show concordance, especially after a clinical intervention. In this study, the development and evaluation of a new approach, using the Rasch model, that combines cognitive and functional measures in one single and more powerful measure (compared to stand-alone tests) to assess global functioning in older adults with cognitive impairment (including dementia) was presented.

Methods

Clinical data from 265 older adults’ subjects diagnosed with mild cognitive impairment, or dementia, included: The Mini-mental state examination (MMSE), the Esame Neuropsicologico Breve (ENB) – a neuropsychological battery used in Italy–, the Activities of Daily Living (ADL), and the Instrumental Activities of Daily Living (IADL) questionnaires.

Results

Patients with severe cognitive impairment showed lower global functioning score compared to patients with moderate impairment. Receiver Operating Characteristic (ROC) curve analyses were performed to determine sensitivity and specificity of the global functioning score resulting from the combined measure. Results showed that the global functioning score discriminates better between patients with severe and moderate cognitive impairment compared to the ENB, ADL, and IADL when considered separately.

Conclusions

The Rasch model was able to combine cognitive and functional measures into a single score (global functioning score). All together, these results suggest that the diverse cognitive and functional measures can be considered part of one single dimension (global functioning) and that this dimension can be measured as a single construct and score. This study offers an alternative perspective for future development of instruments that would help clinicians in measuring global functioning in older adults’ patients at different stages of cognitive impairments and different baseline level of performance.

Clock-drawing test in vascular mild cognitive impairment: Validity of quantitative and qualitative analyses

INTRODUCTION

The clock-drawing test (CDT) has been used as a screening tool to identify cognitive deficit in patients with dementia. However, it has not been extensively evaluated for categorizing patients with vascular mild cognitive impairment (vMCI). This study aimed to examine the discrimination of vMCI using various CDT scoring methods.

METHOD

A total of 120 vMCI patients and 119 normal control (NC) subjects were tested using three CDT quantitative scoring systems: the one from the Montreal Cognitive Assessment (MoCA) (CDT3) and the systems of Rouleau (CDT10) and Babins (CDT18). We used a revised scoring method to evaluate the effectiveness in differentiating vMCI patients from NC subjects, which combined the CDT10 quantitative score and three qualitative errors with a significantly higher prevalence in vMCI group (called hereinafter CDTcomb, including CDTcomb13 and CDTcomb16 based on different weights of the three error types). The sensitivity and specificity of the CDT methods were determined by the receiver operating characteristic (ROC) curve. The results of the scoring systems were compared with those of the Mini-Mental State Examination (MMSE).

RESULTS

The results of the ROC analyses with the CDT3, CDT10, and CDT18 systems produced a sensitivity of 71.1%, 81.8%, and 60.3%, and a specificity of 66.12%, 58.68%, and 73.55%, respectively, for the diagnosis of vMCI. Compared with the separate MMSE score, the combination of MMSE with the CDT3, CDT10 and CDT18 scores did not increase the sensitivity and specificity. When three qualitative errors were incorporated into the CDT10 quantitative score, CDTcomb13 and CDTcomb16 provided a sensitivity of 87.6% and 86.78%, and a specificity of 74.79% and 80.67%, respectively, in differentiating vMCI patients from the NC group.

CONCLUSION

Our findings suggest that the combination of CDT quantitative score with qualitative observations of the clock-drawing errors can provide a better discrimination between vMCI patients and cognitively normal subjects.

Brief Cognitive Tests in the Case of Dementia and Alzheimer's Disease Early Diagnosis

Nowadays, Alzheimer's disease (AD) diagnosis is considered to be a crucial and extremely complex process. Nevertheless, psychometric tools, like Mini-Mental State Evaluation (MMSE), are used to address cognitive function assessment and clinical evaluation processes. However, MMSE's sensitivity in the diagnosis of mild cognitive impairment is debatable in terms of education, age, or nationality. Typical psychometric tools with the use of "paper and pencil" methods combined with physiology measurements are proposed in order to enhance validity and effectiveness in the case of Alzheimer's disease cognitive deficits. The objective of this review study is to highlight the effectiveness of brief cognitive tests (BCT) in the case of dementia and Alzheimer's disease screening. Authors' future work will focus on the application of BCT in MCI diagnosis and evaluation.

Quantitative and Qualitative Analyses of the Clock Drawing Test in Fall and Non-Fall Patients with Alzheimer's Disease

Aim

The clock drawing test (CDT) is widely used as a visual spatial ability test and screening test for dementia patients. The appearance frequency of qualitative errors obtained through the qualitative analysis of CDT may be related to the participant's falls. The aim of this study was to clarify the difference in the number of people who presented with qualitative errors in the CDT between a fall and non-fall group of patients with Alzheimer's disease (AD).

Methods

The CDT was implemented for 47 patients with AD. A quantitative analysis was conducted, and a qualitative analysis was performed for errors. The patients were divided into two groups based on their history of falls over the past year. The results of the CDT quantitative analysis were tested using the Mann-Whitney U test, and Fisher's exact test was employed to determine the difference in the number of people who presented with error types between the two groups (fall group, non-fall group) in the CDT qualitative analysis.

Results

In the quantitative analysis, a significant difference was found for the total scores, with the total CDT score of the fall group (n = 22) significantly lower than that of the non-fall group (n = 25) (p = 0.006, effect size: φ = 0.40). In the qualitative analysis, a significantly higher number of patients in the fall group than in the non-fall group presented with a conceptual deficit (p =0.001, φ = 0.51). No differences were found in the number of patients in the two groups who presented with the other five error types.

Conclusions

These results showed that a lower score in the CDT quantitative analysis might suggest an increased risk of falls. It was also clarified that a larger number of patients in the fall group than in the non-fall group presented with a conceptual deficit of the qualitative error types in the CDT. Therefore, these results suggest that the appearance of a conceptual deficit may be an index for the selection of patients with AD prone to falling when implementing fall prevention measures.

Psychometric properties of cognitive screening for patients with cerebrovascular diseases A systematic review

Screening instruments are ideal for acute clinical settings because they are easy to apply, fast, inexpensive and sensitive for specific samples. However, there is a need to verify the psychometric properties of screening in stroke patients.

Objective

This study investigated the psychometric properties (methodological procedures) of cognitive screening for patients with cerebrovascular diseases.

Methods

A systematic review of papers published on PsycINFO, Web of Knowledge, PubMed and Science Direct (2005 to 2016) was performed.

Results

A total of 55 articles remained after applying exclusion criteria. The samples ranged from 20 to 657 patients. Most articles evaluated elderly individuals with four to 13 years of education who had experienced ischemic or hemorrhagic stroke. There was a tendency to find evidence of validity for criteria and to analyze the sensitivity/specificity of the instruments. Although the studies frequently used the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) to seek evidence of validity and reliability, the use of these instruments among stroke patients has been criticized due to their psychometric properties and the neuropsychological functions evaluated.

Conclusion

Although there is no gold standard screen for assessing adults post-stroke, instruments devised specifically for this population have shown promise. This review helps both researchers and clinicians to select the most appropriate screen for identifying cognitive impairment in adults post-stroke.

Discriminative capacity and construct validity of the Clock Drawing Test in Mild Cognitive Impairment and Alzheimer's disease

Objectives: The aim of this study was to analyze the psychometric and diagnostic properties of the Clock Drawing Test (CDT), scored according to the Babins, Rouleau, and Cahn scoring systems, for Mild Cognitive Impairment (MCI) and Alzheimer's disease (AD) screening, and develop corresponding cutoff scores. Additionally, we assessed the construct validity of the CDT through exploratory and confirmatory factor analysis. Methods: We developed a cross-sectional study of ambulatory MCI and AD patients, divided in two clinical groups (450 MCI and 250 mild AD patients) and a normal control group (N = 400). All participants were assessed with the CDT, Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) for convergent validity. Results: The selected scoring systems presented adequate validity and reliability values. The proposed cutoff scores showed 60 to 65% sensitivity and 58 to 62% specificity to identify MCI patients. The corresponding values for AD were 84 to 90% sensitivity and 76 to 78% specificity. Exploratory and confirmatory factor analysis revealed that the Babins scoring system had good construct validity and allowed us to propose a three-factor model for this system. Conclusions: Our results confirmed the complexity of the CDT and support it as a cognitive screening instrument particularly sensitive to AD. The use of the CDT with MCI patients should be interpreted with more caution due to the lower sensitivity and specificity for milder forms of cognitive impairment.

Clock Drawing Test in acute stroke and its relationship with long-term functional and cognitive outcomes

Objective: The Clock Drawing Test (CDT) is commonly used as a screening tool for the assessment of dementia. The association between the CDT in acute stroke and long-term functional and cognitive outcomes in this population is unknown. The present prospective study is the first to examine if CDT scores in the acute stage after stroke are related to long-term outcomes and to compare the predictive ability of two scoring systems in a large sample of stroke patients. Method: A total of 340 patients admitted to an acute stroke unit were included in the present study. Separate stepwise multiple linear regression analyses were performed with eight independent variables (demographic/pre-stroke variables - age, sex, premorbid functioning; stroke-related variables - stroke severity, localization; cognitive variables - Orientation Test, CDT [2 scoring systems]), and four dependent variables administered one year post-stroke (Barthel Index, modified Rankin Scale, Reintegration to Normal Living index, Global Deterioration Scale). Results: Although both CDT scoring methods were related to all long-term outcome measures, the more comprehensive scoring system was the only baseline variable that significantly explained the variance in outcome measures in all four multiple regression models. Conclusion: Performance on the CDT in acute stroke is related to long-term outcomes including patients' degree of independence in performing activities of daily living, the degree to which they achieved reintegration into daily occupations, and the degree of cognitive decline observed one-year post-stroke. Future studies are needed to clarify the nature of the relationship between different CDT scoring systems and post-stroke outcomes.

A Clinical Research Study of Cognitive Dysfunction and Affective Impairment after Isolated Brainstem Stroke

Although the function of the cerebellum in neurocognition has been well-documented, the similar role of the brainstem has yet to be fully elucidated. This clinical research study aimed to combine data relating to neuropsychological assessments and P300 to explore cognitive dysfunction and affective impairment following brainstem stroke. Thirty-four patients with isolated brainstem stroke and twenty-six healthy controls were recruited; for each patient, we collated data pertaining to the P300, Addenbrooke's Cognitive Examination III (ACE-III), Montreal Cognitive Assessment Chinese version (MoCA), trail-making test (TMT), Symbol Digit Modalities Test (SDMT), Wechsler Adult Intelligence Scale-Digit Spans (DS), Stroop test, Self Rating Depression Scale (SDS), and Self Rating Anxiety Scale (SAS). Significance was analyzed using an independent T-test or the Mann-Whitney U-test. Correlation was analyzed using Pearson's correlation analysis or Spearman's correlation analysis. Collectively, data revealed that brainstem stroke caused mild cognitive impairment (MCI), and that visuospatial, attention, linguistic, and emotional disturbances may occur after isolated brainstem stroke. Cognitive decline was linked to P300 latency, ACE-III, and MoCA; P300 latency was correlated with ACE-III. Patients with right brainstem lesions were more likely to suffer memory decline. The present study provides initial data relating to the role of the brainstem in neurocognition, and will be useful for further understanding of vascular cognitive and affective impairment.

Association of Increased Serum ACE Activity with Logical Memory Ability in Type 2 Diabetic Patients with Mild Cognitive Impairment

Background: Angiotensin-converting enzyme (ACE) is involved in the chronic complications of type 2 diabetes mellitus (T2DM) and Alzheimer's disease. This study aimed to assess the pathogenetic roles of ACE and the genetic predisposition of its insertion/deletion (I/D) polymorphism in mild cognitive impairment (MCI) among T2DM patients.

Methods: A total of 210 T2DM patients were enrolled. Among these patients, 116 satisfied the MCI diagnostic criteria and 94 exhibited healthy cognition. The cognitive functions of the patients were extensively assessed. The serum level and activity of ACE were measured via enzyme-linked immunosorbent assay and ultraviolet spectrophotography. The single-nucleotide polymorphisms of I/D gene of ACE were analyzed.

Results: The serum level and activity of ACE in diabetic MCI patients (p = 0.022 and p = 0.008, respectively) were both significantly higher than those in the healthy controls. A significant negative correlation was found between their ACE activity and logical memory test score (LMT) (p = 0.002). Multiple stepwise regression iterated the negative correlation between ACE activity and LMT score (p = 0.035). Although no significant difference was found in the genotype or allele distribution of ACE I/D polymorphism between the groups, the serum levels and activity of ACE were higher in the DD group than in the ID and II groups (p < 0.05).

Conclusions: Serum ACE activity could better predict logical memory in T2DM patients than ACE level. Further investigations on a large population size are necessary to test whether the D-allele of the ACE gene polymorphism is susceptible to memory deterioration.