Computerized adaptation of The Placing Test for early detection of both mild cognitive impairment and Alzheimer's disease

Digital Cognitive Biomarker for Mild Cognitive Impairments and Dementia: A Systematic Review

The dementia population is increasing as the world’s population is growing older. The current systematic review aims to identify digital cognitive biomarkers from computerized tests for detecting dementia and its risk state of mild cognitive impairment (MCI), and to evaluate the diagnostic performance of digital cognitive biomarkers. A literature search was performed in three databases, and supplemented by a Google search for names of previously identified computerized tests. Computerized tests were categorized into five types, including memory tests, test batteries, other single/multiple cognitive tests, handwriting/drawing tests, and daily living tasks and serious games. Results showed that 78 studies were eligible. Around 90% of the included studies were rated as high quality based on the Newcastle–Ottawa Scale (NOS). Most of the digital cognitive biomarkers achieved comparable or even better diagnostic performance than traditional paper-and-pencil tests. Moderate to large group differences were consistently observed in cognitive outcomes related to memory and executive functions, as well as some novel outcomes measured by handwriting/drawing tests, daily living tasks, and serious games. These outcomes have the potential to be sensitive digital cognitive biomarkers for MCI and dementia. Therefore, digital cognitive biomarkers can be a sensitive and promising clinical tool for detecting MCI and dementia.

Diagnostic performance of digital cognitive tests for the identification of MCI and dementia: A systematic review

BACKGROUND

The use of digital cognitive tests is getting common nowadays. Older adults or their family members may use online tests for self-screening of dementia. However, the diagnostic performance across different digital tests is still to clarify. The objective of this study was to evaluate the diagnostic performance of digital cognitive tests for MCI and dementia in older adults.

METHODS

Literature searches were systematically performed in the OVID databases. Validation studies that reported the diagnostic performance of a digital cognitive test for MCI or dementia were included. The main outcome was the diagnostic performance of the digital test for the detection of MCI or dementia.

RESULTS

A total of 56 studies with 46 digital cognitive tests were included in this study. Most of the digital cognitive tests were shown to have comparable diagnostic performances with the paper-and-pencil tests. Twenty-two digital cognitive tests showed a good diagnostic performance for dementia, with a sensitivity and a specificity over 0.80, such as the Computerized Visuo-Spatial Memory test and Self-Administered Tasks Uncovering Risk of Neurodegeneration. Eleven digital cognitive tests showed a good diagnostic performance for MCI such as the Brain Health Assessment. However, all the digital tests only had a few validation studies to verify their performance.

CONCLUSIONS

Digital cognitive tests showed good performances for MCI and dementia. The digital test can collect digital data that is far beyond the traditional ways of cognitive tests. Future research is suggested on these new forms of cognitive data for the early detection of MCI and dementia.

Distance Assessment for Detecting Cognitive Impairment in Older Adults: A Systematic Review of Psychometric Evidence

INTRODUCTION

Distance or remote cognitive assessments, administered via phone or computer platforms, have emerged as possible alternatives to traditional assessments performed during office visits. Distance refers to any nontraditional assessment feature, not only or necessarily location. We conducted a systematic review to examine the psychometric soundness of these approaches.

METHOD

We searched PubMed, PsycINFO, AgeLine, and Academic Search Premier for articles published between January 2008 and June 2020. Studies were included if participants were over the age of 50, a structured assessment of cognitive function in older adults was evaluated, the assessment method was deemed distant, and validity and/or reliability data were reported. Assessment distance was defined as having any of the following features: use of an electronic test interface, nonroutine test location (e.g., home), test self-administered, and test unsupervised. Distance was categorized as low, intermediate, or high.

RESULTS/DISCUSSION

Twenty-six studies met inclusion criteria. Sample sizes ranged from n = 8 to 8,627, and the mean age ranged from 57 to 83. Assessments included screens, brief or full batteries, and were performed via videoconferencing, phone, smartphone, or tablet/computer. Ten studies reported on low distance, 11 on intermediate distance, and 5 studies for high distance assessments. Invalid performance data were observed with older age and cognitive impairment. Convergent validity data were reported consistently and suggested a decline with increasing distance: r = 0.52-0.80 for low, 0.49-0.75 for intermediate, and 0.41-0.53 for high distance. Diagnostic validity estimates presented a similar pattern. Reliability data were reported too inconsistently to allow evaluation.

CONCLUSION

The validity of cognitive assessments with older adults appears supported at lower but not higher distance. Less is known about the reliability of such assessments. Future research should delineate the person and procedure boundaries for valid and reliable test results.

Comparison of Computerized and Paper-and-Pencil Memory Tests in Detection of Mild Cognitive Impairment and Dementia: A Systematic Review and Meta-analysis of Diagnostic Studies

OBJECTIVES

To compare the diagnostic performance of computerized and paper-and-pencil memory tests in detection of mild cognitive impairment (MCI) and dementia.

DESIGN

Diagnostic studies comparing computerized or paper-and-pencil memory tests with the standard diagnostic criterion for MCI or dementia were identified from OVID databases. The primary outcome was the diagnostic performance of memory tests for detection of MCI, and detection of dementia was the secondary outcome. Risk of bias and reporting quality in included studies was assessed.

SETTING AND PARTICIPANTS

Participants with MCI and dementia in any kind of setting.

MEASURES

Bivariate random-effects models were used to combine the diagnostic performance of memory tests and presented with a summary receiver-operating characteristic curve.

RESULTS

A total of 58 studies with 18,450 participants with mean age ranging from 55 to 84 years were included. For the verbal memory tests on patients with MCI, computerized tests showed diagnostic accuracy of 0.89 sensitivity (95% confidence interval [CI] 0.69-0.97) and 0.82 specificity (95% CI 0.70-0.90), whereas paper-and-pencil tests showed diagnostic accuracy of 0.86 sensitivity (95% CI 0.82-0.90) and 0.82 specificity (95% CI 0.76-0.86). For the visual memory tests on MCI patients, computerized tests showed diagnostic accuracy of 0.79 sensitivity (95% CI 0.71-0.84) and 0.80 specificity (95% CI 0.71-0.86), whereas paper-and-pencil tests showed diagnostic accuracy of 0.80 sensitivity (95% CI 0.67-0.89) and 0.68 specificity (95% CI 0.51-0.81). The findings were also comparable to those with dementia.

CONCLUSIONS/IMPLICATIONS

Both verbal and visual computerized memory tests showed comparable diagnostic performance to the paper-and-pencil tests. Computerized cognitive tests show a great potential to use as an alternative to paper-and-pencil tests. When the records can be digitalized, long-term monitoring of cognitive function will be feasible for better management of dementia.

A systematic review of the diagnostic accuracy of automated tests for cognitive impairment

OBJECTIVE

The aim of this review is to determine whether automated computerised tests accurately identify patients with progressive cognitive impairment and, if so, to investigate their role in monitoring disease progression and/or response to treatment.

METHODS

Six electronic databases (Medline, Embase, Cochrane, Institute for Scientific Information, PsycINFO, and ProQuest) were searched from January 2005 to August 2015 to identify papers for inclusion. Studies assessing the diagnostic accuracy of automated computerised tests for mild cognitive impairment (MCI) and early dementia against a reference standard were included. Where possible, sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratios were calculated. The Quality Assessment of Diagnostic Accuracy Studies tool was used to assess risk of bias.

RESULTS

Sixteen studies assessing 11 diagnostic tools for MCI and early dementia were included. No studies were eligible for inclusion in the review of tools for monitoring progressive disease and response to treatment. The overall quality of the studies was good. However, the wide range of tests assessed and the non-standardised reporting of diagnostic accuracy outcomes meant that statistical analysis was not possible.

CONCLUSION

Some tests have shown promising results for identifying MCI and early dementia. However, concerns over small sample sizes, lack of replicability of studies, and lack of evidence available make it difficult to make recommendations on the clinical use of the computerised tests for diagnosing, monitoring progression, and treatment response for MCI and early dementia. Research is required to establish stable cut-off points for automated computerised tests used to diagnose patients with MCI or early dementia.

A Preliminary Study on the Feasibility of Using a Virtual Reality Cognitive Training Application for Remote Detection of Mild Cognitive Impairment

BACKGROUND

It has been demonstrated that virtual reality (VR) applications can be used for the detection of mild cognitive impairment (MCI).

OBJECTIVE

The aim of this study is to provide a preliminary investigation on whether a VR cognitive training application can be used to detect MCI in persons using the application at home without the help of an examiner.

METHODS

Two groups, one of healthy older adults (n = 6) and one of MCI patients (n = 6) were recruited from Thessaloniki day centers for cognitive disorders and provided with a tablet PC with custom software enabling the self-administration of the Virtual Super Market (VSM) cognitive training exercise. The average performance (from 20 administrations of the exercise) of the two groups was compared and was also correlated with performance in established neuropsychological tests.

RESULTS

Average performance in terms of duration to complete the given exercise differed significantly between healthy(μ  = 247.41 s/ sd = 89.006) and MCI (μ= 454.52 s/ sd = 177.604) groups, yielding a correct classification rate of 91.8% with a sensitivity and specificity of 94% and 89% respectively for MCI detection. Average performance also correlated significantly with performance in Functional Cognitive Assessment Scale (FUCAS), Test of Everyday Attention (TEA), and Rey Osterrieth Complex Figure test (ROCFT).

DISCUSSION

The VR application exhibited very high accuracy in detecting MCI while all participants were able to operate the tablet and application on their own. Diagnostic accuracy was improved compared to a previous study using data from only one administration of the exercise. The results of the present study suggest that remote MCI detection through VR applications can be feasible.

Automated tests for diagnosing and monitoring cognitive impairment: a diagnostic accuracy review

BACKGROUND

Cognitive impairment is a growing public health concern, and is one of the most distinctive characteristics of all dementias. The timely recognition of dementia syndromes can be beneficial, as some causes of dementia are treatable and are fully or partially reversible. Several automated cognitive assessment tools for assessing mild cognitive impairment (MCI) and early dementia are now available. Proponents of these tests cite as benefits the tests' repeatability and robustness and the saving of clinicians' time. However, the use of these tools to diagnose and/or monitor progressive cognitive impairment or response to treatment has not yet been evaluated.

OBJECTIVES

The aim of this review was to determine whether or not automated computerised tests could accurately identify patients with progressive cognitive impairment in MCI and dementia and, if so, to investigate their role in monitoring disease progression and/or response to treatment.

DATA SOURCES

Five electronic databases (MEDLINE, EMBASE, The Cochrane Library, ISI Web of Science and PsycINFO), plus ProQuest, were searched from 2005 to August 2015. The bibliographies of retrieved citations were also examined. Trial and research registers were searched for ongoing studies and reviews. A second search was run to identify individual test costs and acquisition costs for the various tools identified in the review.

REVIEW METHODS

Two reviewers independently screened all titles and abstracts to identify potentially relevant studies for inclusion in the review. Full-text copies were assessed independently by two reviewers. Data were extracted and assessed for risk of bias by one reviewer and independently checked for accuracy by a second. The results of the data extraction and quality assessment for each study are presented in structured tables and as a narrative summary.

RESULTS

The electronic searching of databases, including ProQuest, resulted in 13,542 unique citations. The titles and abstracts of these were screened and 399 articles were shortlisted for full-text assessment. Sixteen studies were included in the diagnostic accuracy review. No studies were eligible for inclusion in the review of tools for monitoring progressive disease. Eleven automated computerised tests were assessed in the 16 included studies. The overall quality of the studies was good; however, the wide range of tests assessed and the non-standardised reporting of diagnostic accuracy outcomes meant that meaningful synthesis or statistical analysis was not possible.

LIMITATIONS

The main limitation of this review is the substantial heterogeneity of the tests assessed in the included studies. As a result, no meta-analyses could be undertaken.

CONCLUSION

The quantity of information available is insufficient to be able to make recommendations on the clinical use of the computerised tests for diagnosing and monitoring MCI and early dementia progression. The value of these tests also depends on the costs of acquisition, training, administration and scoring.

FUTURE WORK

Research is required to establish stable cut-off points for automated computerised tests that are used to diagnose patients with MCI or early dementia. Additionally, the costs associated with acquiring and using these tests in clinical practice should be estimated.

STUDY REGISTRATION

The study is registered as PROSPERO CRD42015025410.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Diagnostic Accuracy of Memory Measures in Alzheimer's Dementia and Mild Cognitive Impairment: a Systematic Review and Meta-Analysis

With an increasing focus on biomarkers in dementia research, illustrating the role of neuropsychological assessment in detecting mild cognitive impairment (MCI) and Alzheimer's dementia (AD) is important. This systematic review and meta-analysis, conducted in accordance with PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) standards, summarizes the sensitivity and specificity of memory measures in individuals with MCI and AD. Both meta-analytic and qualitative examination of AD versus healthy control (HC) studies (n = 47) revealed generally high sensitivity and specificity (≥ 80% for AD comparisons) for measures of immediate (sensitivity = 87%, specificity = 88%) and delayed memory (sensitivity = 89%, specificity = 89%), especially those involving word-list recall. Examination of MCI versus HC studies (n = 38) revealed generally lower diagnostic accuracy for both immediate (sensitivity = 72%, specificity = 81%) and delayed memory (sensitivity = 75%, specificity = 81%). Measures that differentiated AD from other conditions (n = 10 studies) yielded mixed results, with generally high sensitivity in the context of low or variable specificity. Results confirm that memory measures have high diagnostic accuracy for identification of AD, are promising but require further refinement for identification of MCI, and provide support for ongoing investigation of neuropsychological assessment as a cognitive biomarker of preclinical AD. Emphasizing diagnostic test accuracy statistics over null hypothesis testing in future studies will promote the ongoing use of neuropsychological tests as Alzheimer's disease research and clinical criteria increasingly rely upon cerebrospinal fluid (CSF) and neuroimaging biomarkers.

Impact of Omega-3 Fatty Acid Supplementation on Memory Functions in Healthy Older Adults

As the process of Alzheimer's disease (AD) begins years before disease onset, searching for prevention strategies is of major medical and economic importance. Nutritional supplementation with long-chain polyunsaturated omega-3 fatty acids (LC-n3-FA) may exert beneficial effects on brain structure and function. However, experimental evidence in older adults without clinical dementia is inconsistent, possibly due to low sensitivity of previously employed test batteries for detecting subtle improvements in cognition in healthy individuals. Here we used LOCATO, recently described as a robust and sensitive tool for assessing object-location memory (OLM) in older adults, to evaluate the impact of LC-n3-FA supplementation on learning and memory formation. In a double-blind placebo-controlled proof-of-concept study, 44 (20 female) cognitively healthy individuals aged 50-75 years received either LC-n3-FA (2,200 mg/day, n = 22) or placebo (n = 22) for 26 weeks. Before and after intervention, memory performance in the OLM-task (primary) was tested. As secondary outcome parameters, performance in Rey Auditory Verbal Learning Test (AVLT), dietary habits, omega-3-index, and other blood-derived parameters were assessed. Omega-3 index increased significantly in the LC-n3-FA group compared with the placebo group. Moreover, recall of object locations was significantly better after LC-n3-FA supplementation compared with placebo. Performance in the AVLT was not significantly affected by LC-n3-FA. This double-blind placebo-controlled proof-of-concept study provides further experimental evidence that LC-n3-FA exert positive effects on memory functions in healthy older adults. Our findings suggest novel strategies to maintain cognitive functions into old age.

Computerized and on-line neuropsychological testing for late-life cognition and neurocognitive disorders: are we there yet?

PURPOSE OF REVIEW

Cost-effective, valid, efficient and accessible tests for the detection of late-life neurocognitive disorders are crucial, as early identification facilitates appropriate early intervention. Proponents of computerized neuropsychological assessment devices (CNADs) assert that technology-based assessments improve upon traditional neuropsychological tests. However, there remain fundamental questions of validity, reliability, normative data and administration, raising the question of whether CNADs are appropriate alternatives.

RECENT FINDINGS

Since publication of the 2012 American Academy of Clinical Neuropsychology and National Academy of Neuropsychology joint position paper outlining appropriate standards for CNAD development, the field has not significantly advanced, with the majority of recommendations inadequately addressed.

SUMMARY

Whilst there is a pressing need for innovative and readily applicable cognitive tests, these requirements do not outweigh the necessity for valid measures. Overall, the psychometric quality, standardization, normative data and administration advice of CNADs for neurocognitive disorders are lacking. Therefore, the risk of diagnostic errors is potentially high and poor clinical decisions could potentially arise, having significant impact upon individuals in terms of their well being and access to treatment. We recommend clinicians and researchers make informed decisions about CNAD suitability for their clients and their individual requirements based upon published psychometric and other test information.

An object location memory paradigm for older adults with and without mild cognitive impairment

BACKGROUND

Object-location memory is critical in every-day life and known to deteriorate early in the course of neurodegenerative disease.

NEW METHOD

We adapted the previously established learning paradigm "LOCATO" for use in healthy older adults and patients with mild cognitive impairment (MCI). Pictures of real-life buildings were associated with positions on a two-dimensional street map by repetitions of "correct" object-location pairings over the course of five training blocks, followed by a recall task. Correct/incorrect associations were indicated by button presses. The original two 45-item sets were reduced to 15 item-sets, and tested in healthy older adults and MCI for learning curve, recall, and re-test effects.

RESULTS

The two 15-item versions showed comparable learning curves and recall scores within each group. While learning curves increased linearly in both groups, MCI patients performed significantly worse on learning and recall compared to healthy controls. Re-testing after 6 month showed small practice effects only.

COMPARISON WITH EXISTING METHODS

LOCATO is a simple standardized task that overcomes several limitation of previously employed visuospatial task by using real-life stimuli, minimizing verbal encoding, avoiding fine motor responses, combining explicit and implicit statistical learning, and allowing to assess learning curve in addition to recall.

CONCLUSIONS

Results show that the shortened version of LOCATO meets the requirements for a robust and ecologically meaningful assessment of object-location memory in older adults with and without MCI. It can now be used to systematically assess acquisition of object-location memory and its modulation through adjuvant therapies like pharmacological or non-invasive brain stimulation.