Screening for mild cognitive impairment: a systematic review

Mild cognitive impairment in primary care: a clinical review

Dementia is projected to become a global health priority but often not diagnosed in its earlier preclinical stage which is mild cognitive impairment (MCI). MCI is generally referred as a transition state between normal cognition and Alzheimer’s disease. Primary care physicians play an important role in its early diagnosis and identification of patients most likely to progress to Alzheimer’s disease while offering evidenced-based interventions that may reverse or halt the progression to further cognitive impairment. The aim of this review is to introduce the concept of MCI in primary care through a case-based clinical review. We discuss the case of a patient with MCI and provide an evidence-based framework for assessment, early recognition and management of MCI while addressing associated risk factors, neuropsychiatric symptoms and prognosis.

Rapid review of cognitive screening instruments in MCI: proposal for a process-based approach modification of overlapping tasks in select widely used instruments

ABSTRACTBackground:A detailed neuropsychological assessment plays an important role in the diagnostic process of Mild Cognitive Impairment (MCI). However, available brief cognitive screening tests for this clinical population are administered and interpreted based mainly, or exclusively, on total achievement scores. This score-based approach can lead to erroneous clinical interpretations unless we also pay attention to the test taking behavior or to the type of errors committed during test performance.

METHODS

The goal of the current study is to perform a rapid review of the literature regarding cognitive screening tools for dementia in primary and secondary care; this will include revisiting previously published systematic reviews on screening tools for dementia, extensive database search, and analysis of individual references cited in selected studies.

RESULTS

A subset of representative screening tools for dementia was identified that covers as many cognitive functions as possible. How these screening tools overlap with each other (in terms of the cognitive domains being measured and the method used to assess them) was examined and a series of process-based approach (PBA) modifications for these overlapping features was proposed, so that the changes recommended in relation to one particular cognitive task could be extrapolated to other screening tools.

CONCLUSION

It is expected that future versions of cognitive screening tests, modified using a PBA, will highlight the benefits of attending to qualitative features of test performance when trying to identify subtle features suggestive of MCI and/or dementia.

Within-Individual Variability: An Index for Subtle Change in Neurocognition in Mild Cognitive Impairment

BACKGROUND

The transition from mild cognitive impairment (MCI) to Alzheimer's disease is characterized by a decline in cognitive performance in many domains. Cognitive performance profiles in MCI are heterogeneous, however, and additional insights into markers of incipient dementia are needed. Typically, studies focus on average or mean performance, but ignore consistency of performance across domains. WIV (within-individual variability) provides an index of this consistency and is a potential marker of cognitive decline.

OBJECTIVE

To use neurocognitive data from the Alzheimer's Disease Neuroimaging Initiative cohort to measure neurocognitive variability.

METHODS

The utility of WIV was measured, in addition to global neurocognitive performance (GNP), for identifying AD and MCI. In addition, the association between changes in neurocognitive variability and diagnostic transition over 12 months was measured.

RESULTS

As expected, variability was higher in AD and MCI as compared to healthy controls; GNP was lower in both groups as compared to healthy subjects. Global neurocognitive performance alone best distinguished those with dementia from healthy older adults. Yet, for individuals with MCI, including variability along with GNP improved diagnostic classification. Variability was higher at baseline in individuals transitioning from MCI to AD over a 12-month period.

CONCLUSION

We conclude that variability offers complementary information about neurocognitive performance in dementia, particularly in individuals with MCI, and may provide beneficial information about disease transition.

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.

Cognitive-Motor Interference during Walking in Older Adults with Probable Mild Cognitive Impairment

Although several studies have shown that dual-tasking (DT) mobility is impaired in Alzheimer's disease, studies on the effects of DT conditions in probable Mild Cognitive Impairment (pMCI) have not yielded unequivocal results. The objectives of the study were to (1) examine the effect of a concurrent task on a complex walking task in adults with cognitive impairment; and (2) determine whether the effect varied with different difficulty levels of the concurrent task. Furthermore, the study was designed to evaluate the Trail-Walking Test (TWT) as a potential detection tool for MCI. We examined DT performance in 42 young adults (mean age 23.9 ± 1.98), and 43 older adults (mean age 68.2 ± 6.42). The MoCA was used to stratify the subjects into those with and without pMCI. DT was assessed using the TWT: participants completed 5 trials each of walking along a fixed pathway, stepping on targets with increasing sequential numbers (i.e., 1-2-…-15), and increasing sequential numbers and letters (i.e., 1-A-2-B-3-…-8). Motor and cognitive DT effects (DTE) were calculated for each task. ROC curves were used to distinguish younger and healthy older adults from older adults with pMCI. The TWT showed excellent test-retest reliability across all conditions and groups (ICC : 0.83–0.97). SEM% was also low (<11%) as was the MDC95% (<30%). Within the DT conditions, the pMCI group showed significantly longer durations for all tasks regardless of the cognitive load compared to the younger and the healthy older adults. The motor DTEs were greatest for the complex condition in older adults with pMCI more so than in comparison with younger and healthy older adults. ROC analyses confirmed that only the tasks with higher cognitive load could differentiate older adults with pMCI from controls (area under the curve >0.7, p < 0.05). The TWT is a reliable DT mobility measure in people with pMCI. However, the condition with high cognitive load is more sensitive than the condition with low cognitive load in identifying pMCI. The TWT-3 thus could serve as a screening tool for early detection of individuals with pMCI. Future studies need to determine the neural correlates for cognitive-motor interference in older adults with pMCI.

Anserine/Carnosine Supplementation Suppresses the Expression of the Inflammatory Chemokine CCL24 in Peripheral Blood Mononuclear Cells from Elderly People

Our goal was to determine whether anserine/carnosine supplementation (ACS) suppresses chemokine levels in elderly people. In a double-blind randomized controlled trial, volunteers were assigned to the ACS or placebo group (1:1). Sixty healthy elderly volunteers (active, n = 30; placebo, n = 30) completed the study. The ACS group was administered 1.0 g of anserine/carnosine (3:1) for 3 months. A microarray analysis and subsequent quantitative real-time polymerase chain reaction (qRT-PCR) analysis of peripheral blood mononuclear cells (PBMCs) showed decreased expression of CCL24, an inflammatory chemokine (p < 0.05). Verbal memory, assessed using the Wechsler memory scale-logical memory, was preserved in the ACS group. An age-restricted sub-analysis showed significant verbal memory preservation by ACS in participants who were in their 60s (active, n = 12; placebo, n = 9; p = 0.048) and 70s (active, n = 7; placebo, n = 11; p = 0.017). The suppression of CCL24 expression was greatest in people who were in their 70s (p < 0.01). There was a significant correlation between the preservation of verbal memory and suppression of CCL24 expression in the group that was in the 70s (Poisson correlation, r = 0.46, p < 0.05). These results suggest that ACS may preserve verbal episodic memory, probably owing to CCL24 suppression in the blood, especially in elderly participants.

Vascular Aging and Cognitive Dysfunction: Silent Midlife Crisis in the Brain

Background

Vascular aging may cause cerebral microvascular damage and cognitive dysfunction. There is incremental evidence that consistently implicates arterial stiffness being involved in the manifestation of cognitive impairment in the elderly. However, few investigations have examined the relationship between arterial stiffness and cognitive impairment in midlife.

Summary

Past studies inconsistently showed improved cognitive outcomes after antihypertensive therapy in elderly populations. Nevertheless, recent findings revealed that blood-pressure-lowering treatment in young adults might eliminate or halt the progression of the detrimental effects related to arterial stiffness, indicating that younger adults may have more favorable outcomes in cognition than their older counterparts if early intervention is conducted at the subclinical stage. Stiffening of the aorta may lead to an excessive flow pulsatility in the brain that may cause microvascular structural brain damage and worse cognitive performance. Recent investigations have suggested that arterial stiffness is likely to trigger initial silent brain damage, possibly preceding midlife, while the manifestation of cognitive decline and deterioration can be foreseen in the subsequent life span.

Key Message

Despite the recent novel findings, definite conclusions on causality between vascular aging and cognitive dysfunction cannot be drawn at present. Further well-powered longitudinal studies with superior neuroimaging indicator, vascular mechanical biomarkers, and sensitive cognitive assessment tools that examine a broad range of age populations may help extend our understanding of the association between vascular aging and cognitive dysfunction throughout the life span.

Potential contribution of the neurodegenerative disorders risk loci to cognitive performance in an elderly male gout population

Cognitive impairment has been described in elderly subjects with high normal concentrations of serum uric acid. However, it remains unclear if gout confers an increased poorer cognition than those in individuals with asymptomatic hyperuricemia. The present study aimed at evaluating cognitive function in patients suffering from gout in an elderly male population, and further investigating the genetic contributions to the risk of cognitive function.This study examined the cognitive function as assessed by Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) in 205 male gout patients and 204 controls. The genetic basis of these cognitive measures was evaluated by genome-wide association study (GWAS) data in 102 male gout patients. Furthermore, 7 loci associated with cognition in GWAS were studied for correlation with gout in 1179 male gout patients and 1848 healthy male controls.Compared with controls, gout patients had significantly lower MoCA scores [22.78 ± 3.01 vs 23.42 ± 2.95, P = .023, adjusted by age, body mass index (BMI), education, and emotional disorder]. GWAS revealed 7 single-nucleotide polymorphisms (SNPs) associations with MoCA test at a level of conventional genome-wide significance (P < 9.6 × 10). The most significant association was observed between rs12895072 and rs12434554 within the KTN1 gene (Padjusted = 4.2 × 10, Padjusted = 4.7 × 10) at 14q22. The next best signal was in RELN gene (rs155333, Padjusted = 1.3 × 10) at 7q22, while the other variants at rs17458357 (Padjusted = 3.98 × 10), rs2572683 (Padjusted = 8.9 × 10), rs12555895 (Padjusted = 2.6 × 10), and rs3764030 (Padjusted = 9.4 × 10) were also statistically significant. The 7 SNPs were not associated with gout in further analysis (all P > .05).Elderly male subjects with gout exhibit accelerated decline in cognition performance. Several neurodegenerative disorders risk loci were identified for genetic contributors to cognitive performance in our Chinese elderly male gout population. Larger prospective studies of the cognitive performance and genetic analysis in gout subjects are recommended.

Memory Alteration Test to Detect Amnestic Mild Cognitive Impairment and Early Alzheimer's Dementia in Population with Low Educational Level

Background/Aims: Short tests to early detection of the cognitive impairment are necessary in primary care setting, particularly in populations with low educational level. The aim of this study was to assess the performance of Memory Alteration Test (M@T) to discriminate controls, patients with amnestic Mild Cognitive Impairment (aMCI) and patients with early Alzheimer’s Dementia (AD) in a sample of individuals with low level of education.

Methods: Cross-sectional study to assess the performance of the M@T (study test), compared to the neuropsychological evaluation (gold standard test) scores in 247 elderly subjects with low education level from Lima-Peru. The cognitive evaluation included three sequential stages: (1) screening (to detect cases with cognitive impairment); (2) nosological diagnosis (to determinate specific disease); and (3) classification (to differentiate disease subtypes). The subjects with negative results for all stages were considered as cognitively normal (controls). The test performance was assessed by means of area under the receiver operating characteristic (ROC) curve. We calculated validity measures (sensitivity, specificity and correctly classified percentage), the internal consistency (Cronbach’s alpha coefficient), and concurrent validity (Pearson’s ratio coefficient between the M@T and Clinical Dementia Rating (CDR) scores).

Results: The Cronbach’s alpha coefficient was 0.79 and Pearson’s ratio coefficient was 0.79 (p < 0.01). The AUC of M@T to discriminate between early AD and aMCI was 99.60% (sensitivity = 100.00%, specificity = 97.53% and correctly classified = 98.41%) and to discriminate between aMCI and controls was 99.56% (sensitivity = 99.17%, specificity = 91.11%, and correctly classified = 96.99%).

Conclusions: The M@T is a short test with a good performance to discriminate controls, aMCI and early AD in individuals with low level of education from urban settings.

Temporal trend in dementia incidence since 2002 and projections for prevalence in England and Wales to 2040: modelling study

Objective To forecast dementia prevalence with a dynamic modelling approach that integrates calendar trends in dementia incidence with those for mortality and cardiovascular disease.Design Modelling study.Setting General adult population of England and Wales.Participants The English Longitudinal Study of Ageing (ELSA) is a representative panel study with six waves of data across 2002-13. Men and women aged 50 or more years, selected randomly, and their cohabiting partners were recruited to the first wave of ELSA (2002-03). 11392 adults participated (response rate 67%). To maintain representativeness, refreshment participants were recruited to the study at subsequent waves. The total analytical sample constituted 17 906 people. Constant objective criteria based on cognitive and functional impairment were used to ascertain dementia cases at each wave.Main outcome measures To estimate calendar trends in dementia incidence, correcting for bias due to loss to follow-up of study participants, a joint model of longitudinal and time-to-event data was fitted to ELSA data. To forecast future dementia prevalence, the probabilistic Markov model IMPACT-BAM (IMPACT-Better Ageing Model) was developed. IMPACT-BAM models transitions of the population aged 35 or more years through states of cardiovascular disease, cognitive and functional impairment, and dementia, to death. It enables prediction of dementia prevalence while accounting for the growing pool of susceptible people as a result of increased life expectancy and the competing effects due to changes in mortality, and incidence of cardiovascular disease.Results In ELSA, dementia incidence was estimated at 14.3 per 1000 person years in men and 17.0/1000 person years in women aged 50 or more in 2010. Dementia incidence declined at a relative rate of 2.7% (95% confidence interval 2.4% to 2.9%) for each year during 2002-13. Using IMPACT-BAM, we estimated there were approximately 767 000 (95% uncertainty interval 735 000 to 797 000) people with dementia in England and Wales in 2016. Despite the decrease in incidence and age specific prevalence, the number of people with dementia is projected to increase to 872 000, 1 092 000, and 1 205 000 in 2020, 2030, and 2040, respectively. A sensitivity analysis without the incidence decline gave a much larger projected growth, of more than 1.9 million people with dementia in 2040.Conclusions Age specific dementia incidence is declining. The number of people with dementia in England and Wales is likely to increase by 57% from 2016 to 2040. This increase is mainly driven by improved life expectancy.

Brief Report: Using the Internet to Identify Persons with Cognitive Impairment for Participation in Clinical Trials

Identifying, recruiting, and enrolling persons in clinical trials of dementia treatments is extremely difficult. One approach to first-wave screening of potential participants is the use of online assessment tools. Initial studies using the Dementia Risk Assessment (DRA)—which includes a previously validated recognition memory test—support the use of this self-administered assessment to identify individuals with “suspected MCI” or “suspected dementia.” In this study, we identified between 71 and 622 persons with suspected dementia and between 128 and 1653 persons with suspected mild cognitive impairment (depending on specific criteria) over the course of 22 months. Assessment tools that can inexpensively and easily identify individuals with higher than average risk for cognitive impairment can facilitate recruitment for large-scale clinical trials for dementia treatments.

Cognitive impairment in COPD: should cognitive evaluation be part of respiratory assessment?

Cognitive impairment is highly prevalent in patients with COPD and demonstrates multiple detrimental effects on many aspects of patient state and therapeutic outcomes. It is attributed to several overlapping pathophysiological factors, with the most common being the low level of oxygen saturation due to respiratory insufficiency. Despite the impact of cognitive impairment on clinical outcomes, the screening for coexisting cognitive deficits which may interfere with the successful progress of respiratory treatment is yet neglected. There is a special consideration that cognitive deficits should be taken into account when developing respiratory therapy plans. Cognitively impaired patients are likely to require more support and have need of an individualised respiratory care plan which can also be beneficial for their cognitive deficits. Pulmonary rehabilitation as a multidisciplinary approach could be prioritised for COPD patients with cognitive impairment.

EDUCATIONAL AIMS

To illustrate the common signs of cognitive impairment and define potential associations between lung and cognitive dysfunction.To illustrate the potential influence of cognitive deficits on the optimal progress of respiratory therapy.To illustrate the importance of cognitive evaluation as part of a comprehensive clinical assessment for patients suspected of suffering cognitive impairment.

Screening for Mild Cognitive Impairment: Comparison of "MCI Specific" Screening Instruments

Background:

Sensitive and specific instruments are required to screen for cognitive impairment (CI) in busy clinical practice. The Montreal Cognitive Assessment (MoCA) is widely validated but few studies compare it to tests designed specifically to detect mild cognitive impairment (MCI).

Objective:

Comparison of two “MCI specific” screens: the Quick Mild Cognitive Impairment screen (Qmci) and MoCA.

Methods:

Patients with subjective memory complaints (SMC; n = 73), MCI (n = 103), or dementia (n = 274), were referred to a university hospital memory clinic and underwent comprehensive assessment. Caregivers, without cognitive symptoms, were recruited as normal controls (n = 101).

Results:

The Qmci was more accurate than the MoCA in differentiating MCI from controls, area under the curve (AUC) of 0.90 versus 0.80, p = 0.009. The Qmci had greater (AUC 0.81), albeit non-significant, accuracy than the MoCA (AUC 0.73) in separating MCI from SMC, p = 0.09. At its recommended cut-off (<62/100), the Qmci had a sensitivity of 90% and specificity of 87% for CI (MCI/dementia). Raising the cut-off to <65 optimized sensitivity (94%), reducing specificity (80%). At <26/30 the MoCA had better sensitivity (96%) but poor specificity (58%). A MoCA cut-off of <24 provided the optimal balance. Median Qmci administration time was 4.5 (±1.3) minutes compared with 9.5 (±2.8) for the MoCA.

Conclusions:

Although both tests distinguish MCI from dementia, the Qmci is particularly accurate in separating MCI from normal cognition and has shorter administration times, suggesting it is more useful in busy hospital clinics. This study reaffirms the high sensitivity of the MoCA but suggests a lower cut-off (<24) in this setting.

Diagnosing early cognitive decline-When, how and for whom?

Mild cognitive impairment (MCI) is a term used to describe cognitive impairment in one or more cognitive domains that is greater than any expected age-related changes, but not of the magnitude to warrant a diagnosis of dementia. This review considers how early cognitive decline is diagnosed, focusing on the use of neuropsychological tests and neuroimaging, as well as the differential diagnosis. Potential treatments, including secondary prevention, post-diagnostic support and self-help are discussed. Finally, medico-legal matters such as driving, lasting power of attorney and employment are outlined.

A systematic review of the diagnostic test accuracy of brief cognitive tests to detect amnestic mild cognitive impairment

OBJECTIVE

People with amnestic mild cognitive impairment (aMCI) are at an increased risk of developing dementia. Efficient ways of identifying this 'at risk' population are required for larger-scale research studies. This systematic review describes the diagnostic accuracy of brief cognitive tests for detecting aMCI.

METHODS

Fifteen databases were searched from 1999 to July 2013 to identify papers for inclusion. Prospective studies assessing the diagnostic test accuracy of simple and brief cognitive tests for identifying people with aMCI against a reference standard (Petersen criteria) were included. Sensitivity, specificity, positive and negative predictive values and likelihood ratios were calculated. Predictive validity and test-retest reliability were also extracted, when provided. Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool.

RESULTS

Thirty-nine studies assessing 42 index tests were included. The Montreal Cognitive Assessment was the most comprehensively assessed test with evidence of high sensitivity for aMCI and good test-retest reliability, but low specificity was reported by the only study judged to be at low risk of bias. Other brief cognitive tests that include an assessment of word recall and multi-task tests that assess several cognitive domains were also found to exhibit high sensitivities and reasonable specificities. However, the confidence of the findings was affected by overall low quality of the contributing studies.

CONCLUSION

Several brief cognitive tests have shown promising diagnostic test accuracy results for identifying aMCI. However, concerns over the quality of the constituent studies and lack of evidence on the predictive validity of these tests mean that new validation studies are warranted. Copyright © 2016 John Wiley & Sons, Ltd.

Prognostic Significance of Mild Cognitive Impairment Subtypes for Dementia and Mortality: Data from the NEDICES Cohort

BACKGROUND

The predictive value of diverse subtypes of mild cognitive impairment (MCI) for dementia and death is highly variable.

OBJECTIVE

To compare the predictive value of several MCI subtypes in progression to dementia and/or mortality in the NEDICES (Neurological Disorders in Central Spain) elderly cohort.

METHODS

Retrospect algorithmic MCI subgroups were established in a non-dementia baseline NEDICES cohort using Spanish adaptations of the original Mini-Mental State Examination (MMSE-37) and Pfeffer's Functional Activities Questionnaire (Pfeffer-11). The presence of MCI was defined according two cognitive criteria: using two cut-offs points on the total MMSE-37 score. Five cognitive domains were used to establish the MCI subtypes. Functional capacity (Pfeffer-11) was preserved or minimally impaired in all MCI participants. The incident dementia diagnoses were established by specialists and the mortality data obtained from Spanish official registries.

RESULTS

3,411 participants without dementia were assessed in 1994-5. The baseline prevalence of MCI varied according to the MCI definition (4.3%-31.8%). The follow-up was a mean of 3.2 years (1997-8). The dementia incidence varied between 14.9 and 71.8 per 1,000/person-years. The dementia conversion rate was increased in almost all MCI subgroups (p >  0.01), and mortality rate was raised only in four MCI subtypes. The amnestic-multi-domain MCI (aMd-MCI) had the best dementia predictive accuracy (highest positive likelihood ratio and highest clinical utility when negative).

CONCLUSIONS

Those with aMd-MCI were at greatest risk of progression to dementia, as in other surveys and might be explored with increased attention in MCI research and in dementia preventive trials.

Differences in cognitive profiles between traumatic brain injury and stroke: A comparison of the Montreal Cognitive Assessment and Mini-Mental State Examination

PURPOSE

To investigate the profiles of cognitive impairment through Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE) in patients with chronic traumatic brain injury (TBI) or stroke and to evaluate the sensitivity of the two scales in patients with TBI.

METHODS

In this cohort study, a total of 230 patients were evaluated, including TBI group (n = 103) and stroke group (n = 127). The cognitive functions of two groups were evaluated by designated specialists using MoCA (Beijing version) and MMSE (Chinese version).

RESULTS

Comparedwith the patientswith stroke, the patientswith TBI received significantly lower score in orientation subtest and recall subtest in both tests.MoCA abnormal rates in the TBI group and stroke group were 94.17% and 86.61% respectively,whileMMSE abnormal rateswere 69.90% and 57.48%, respectively. In the TBI group, 87.10% patientswith normalMMSE score had abnormalMoCA score and in the stroke group, about 70.37% patients with normal MMSE score had abnormal MoCA score. The diagnostic consistency of two scales in the TBI group and the stroke group were 72% and 69%, respectively.

CONCLUSION

In our rehabilitation center, patients with TBI may have more extensive and severe cognitive impairments than patients with stroke, prominently in orientation and recall domain. In screening post- TBI cognitive impairment, MoCA tends to be more sensitive than MMSE.

Effect of Anserine/Carnosine Supplementation on Verbal Episodic Memory in Elderly People

Our goal in this study was to determine whether or not anserine/carnosine supplementation (ACS) is capable of preserving cognitive function of elderly people. In a double-blind randomized controlled trial, volunteers were randomly assigned to an ACS or placebo group at a 1:1 ratio. The ACS group took 1.0 g of an anserine/carnosine (3:1) formula daily for 3 months. Participants were evaluated by psychological tests before and after the 3-month supplementation period. Thirty-nine healthy elderly volunteers (60–78 years old) completed the follow-up tests. Among the tests, delayed recall verbal memory assessed by the Wechsler Memory Scale-Logical Memory showed significant preservation in the ACS group, compared to the placebo group (p = 0.0128). Blood analysis revealed a decreased secretion of inflammatory cytokines, including CCL-2 and IL-8, in the ACS group. MRI analysis using arterial spin labeling showed a suppression in the age-related decline in brain blood flow in the posterior cingulate cortex area in the ACS group, compared to the placebo group (p = 0.0248). In another randomized controlled trial, delayed recall verbal memory showed significant preservation in the ACS group, compared to the placebo group (p = 0.0202). These results collectively suggest that ACS may preserve verbal episodic memory and brain perfusion in elderly people, although further study is needed.

The Utility of Brief Cognitive Tests for Patients With Type 2 Diabetes Mellitus: A Systematic Review

BACKGROUND

Type 2 diabetes mellitus (T2DM) is associated with an increased risk for mild cognitive impairment and dementia in both middle-aged and older individuals. Brief cognitive tests can potentially serve as a reliable and cost effective approach to detect for cognitive decrements in clinical practice.

OBJECTIVE

This systematic review examined the utility of brief cognitive tests in studies with patients with T2DM.

METHOD

This systematic review was conducted according to guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. "PubMed," "PsychINFO," "ScienceDirect," and "ProQuest" electronic databases were searched to identify articles published from January 1, 2005 to December 31, 2015.

RESULTS

The search yielded 22 studies, with only 8 using brief tests as a cognitive screening tool, whereas the majority using these tests as a measure of global cognitive functions. In regard to cognitive screening studies, most had failed to fulfil the standard reporting of diagnostic test accuracy criteria such as Standards for Reporting of Diagnostic Accuracy for dementia and cognitive impairment. Moreover, few studies reported discriminant indices such as sensitivity, specificity, and positive and negative predictive values of brief cognitive tests in detecting cognitive impairment in patients with T2DM. Among studies which used brief cognitive tests as a measure of global cognitive function, patients with diabetes tended to perform worse than patients without diabetes. Processing speed appeared to be particularly impaired among patients with diabetes, therefore, measures of processing speed such as the Digit Symbol Substitution Test may add value to brief cognitive tests such as the Montreal Cognitive Assessment.

CONCLUSIONS

The Montreal Cognitive Assessment supplemented by the Digit Symbol Substitution Test indicate initial promise in screening for cognitive impairment in T2DM.

Mini Mental State Examination and Logical Memory scores for entry into Alzheimer's disease trials

Background

Specific cutoff scores on the Mini Mental State Examination (MMSE) and the Logical Memory (LM) test are used to determine inclusion in Alzheimer’s disease (AD) clinical trials and diagnostic studies. These screening measures have known psychometric limitations, but no study has examined the diagnostic accuracy of the cutoff scores used to determine entry into AD clinical trials and diagnostic studies.

Methods

ClinicalTrials.gov entries were reviewed for phases II and III active and recruiting AD studies using the MMSE and LM for inclusion. The diagnostic accuracy of MMSE and LM-II cutoffs used in AD trials and diagnostic studies was examined using 23,438 subjects with normal cognition, mild cognitive impairment (MCI), and AD dementia derived from the National Alzheimer’s Coordinating Center database.

Results

MMSE and LM cutoffs used in current AD clinical trials and diagnostic studies had limited diagnostic accuracy, particularly for distinguishing between normal cognition and MCI, and MCI from AD dementia. The MMSE poorly discriminated dementia stage.

Conclusions

The MMSE and LM may result in inappropriate subject enrollment in large-scale, multicenter studies designed to develop therapeutics and diagnostic methods for AD.

Detecting Change over Time: A Comparison of the SLUMS Examination and the MMSE in Older Adults at Risk for Cognitive Decline

AIMS

To directly compare the 1-year stability of Mini-Mental State Examination (MMSE) score and Saint Louis University Mental Status (SLUMS) examination score and correlate score changes with demographic variables, clinical factors, and functional domains.

METHODS

A sample of 304 study participants was recruited from residential and clinical settings in Ohio. Follow-up assessments were administered after 1 year with a retention rate of 92% (n = 281). Functional domains included the Instrumental Activities of Daily Living (IADL) scale.

RESULTS

MMSE and SLUMS scores correlated with each other (r = 0.65, P < 0.001) and with two functional measures, including the IADL (r = 0.27, r = 0.24, P < 0.001). However, the MMSE and SLUMS frequently placed the same subject into different categories. Rates of reversion and conversion varied between the two tests. The 1-year changes in MMSE raw score correlated with changes in three functional domains as well as age (P < 0.05), while SLUMS raw score changes did not correlate with any functional measures.

CONCLUSION

Our large, longitudinal data set allowed us to compare the tests' stability, which differed between the SLUMS and MMSE. The MMSE may be more sensitive than the SLUMS to 1-year cognitive changes influencing functional abilities.

Development of a self-administered web-based test for longitudinal cognitive assessment

Sequential testing with brief cognitive tools has been recommended to improve cognitive screening and monitoring, however the few available tools still depend on an external evaluator and periodic visits. We developed a self-administered computerized test intended for longitudinal cognitive testing (Brain on Track). The test can be performed from a home computer and is composed of several subtests, expected to evaluate different cognitive domains, all including random elements to minimize learning effects. An initial (A) and a refined version of the test (B) were applied to patients with mild cognitive impairment or early dementia (n = 88) and age and education-matched controls. A subsample of a population-based cohort (n = 113) performed the test at home every three months to evaluate test-retest reliability. The test’s final version Cronbach’s alpha was 0.90, test scores were significantly different between patients and controls (p = 0.001), the area under the receiver operating characteristic curve was 0.75 and the smallest real difference (43.04) was lower than the clinical relevant difference (56.82). In the test-retest reliability analysis 9/10 subtests showed two-way mixed single intraclass consistency correlation coefficient >0.70. These results imply good internal consistency, discriminative ability and reliability when performed at home, encouraging further longitudinal clinical and population-based studies.

Lifting the veil: how to use clinical neuropsychology to assess dementia

Neurologists often struggle to interpret the results of neuropsychological testing, even though cognitive assessments are an integral component of the diagnostic process in dementia syndromes. This article reviews the principles underlying clinical neuropsychology, background on common neuropsychological tests, and tips on how to interpret the results when assessing patients with dementia. General cognitive screening tools, appropriate for use by general neurologists and psychiatrists, as well as specific cognitive tests examining the main cognitive domains (attention and orientation, memory, visuospatial function, language and executive function) in patients with dementia are considered. Finally, the pattern of deficits, helpful in defining clinical dementia phenotypes and sometimes in predicting the underlying molecular pathology, are outlined. Such clinicopathological associations will become invaluable as disease-modifying treatments for dementia are developed and implemented.

Mild cognitive decline. A position statement of the Cognitive Decline Group of the European Innovation Partnership for Active and Healthy Ageing (EIPAHA)

INTRODUCTION

Mild cognitive impairment (MCI) is a term used to describe a level of decline in cognition which is seen as an intermediate stage between normal ageing and dementia, and which many consider to be a prodromal stage of neurodegeneration that may become dementia. That is, it is perceived as a high risk level of cognitive change. The increasing burden of dementia in our society, but also our increasing understanding of its risk factors and potential interventions, require diligent management of MCI in order to find strategies that produce effective prevention of dementia.

AIM

To update knowledge regarding mild cognitive impairment, and to bring together and appraise evidence about the main features of clinical interest: definitions, prevalence and stability, risk factors, screening, and management and intervention.

METHODS

Literature review and consensus of expert opinion.

RESULTS AND CONCLUSION

MCI describes a level of impairment in which deteriorating cognitive functions still allow for reasonable independent living, including some compensatory strategies. While there is evidence for some early risk factors, there is still a need to more precisely delineate and distinguish early manifestations of frank dementia from cognitive impairment that is less likely to progress to dementia, and furthermore to develop improved prospective evidence for positive response to intervention. An important limitation derives from the scarcity of studies that take MCI as an endpoint. Strategies for effective management suffer from the same limitation, since most studies have focused on dementia. Behavioural changes may represent the most cost-effective approach.

Relationship between the Montreal Cognitive Assessment and Mini-mental State Examination for assessment of mild cognitive impairment in older adults

BACKGROUND

The Montreal Cognitive Assessment (MoCA) was developed to enable earlier detection of mild cognitive impairment (MCI) relative to familiar multi-domain tests like the Mini-Mental State Exam (MMSE). Clinicians need to better understand the relationship between MoCA and MMSE scores.

METHODS

For this cross-sectional study, we analyzed 219 healthy control (HC), 299 MCI, and 100 Alzheimer's disease (AD) dementia cases from the Alzheimer's Disease Neuroimaging Initiative (ADNI)-GO/2 database to evaluate MMSE and MoCA score distributions and select MoCA values to capture early and late MCI cases. Stepwise variable selection in logistic regression evaluated relative value of four test domains for separating MCI from HC. Functional Activities Questionnaire (FAQ) was evaluated as a strategy to separate dementia from MCI. Equi-percentile equating produced a translation grid for MoCA against MMSE scores. Receiver Operating Characteristic (ROC) analyses evaluated lower cutoff scores for capturing the most MCI cases.

RESULTS

Most dementia cases scored abnormally, while MCI and HC score distributions overlapped on each test. Most MCI cases scored ≥ 17 on MoCA (96.3%) and ≥ 24 on MMSE (98.3%). The ceiling effect (28-30 points) for MCI and HC was less using MoCA (18.1%) versus MMSE (71.4%). MoCA and MMSE scores correlated most for dementia (r = 0.86; versus MCI r = 0.60; HC r = 0.43). Equi-percentile equating showed a MoCA score of 18 was equivalent to MMSE of 24. ROC analysis found MoCA ≥ 17 as the cutoff between MCI and dementia that emphasized high sensitivity (92.3%) to capture MCI cases. The core and orientation domains in both tests best distinguished HC from MCI groups, whereas comprehension/executive function and attention/calculation were not helpful. Mean FAQ scores were significantly higher and a greater proportion had abnormal FAQ scores in dementia than MCI and HC.

CONCLUSIONS

MoCA and MMSE were more similar for dementia cases, but MoCA distributes MCI cases across a broader score range with less ceiling effect. A cutoff of ≥ 17 on the MoCA may help capture early and late MCI cases; depending on the level of sensitivity desired, ≥ 18 or 19 could be used. Functional assessment can help exclude dementia cases. MoCA scores are translatable to the MMSE to facilitate comparison.

Innate Immune Signalling Genetics of Pain, Cognitive Dysfunction and Sickness Symptoms in Cancer Pain Patients Treated with Transdermal Fentanyl

Common adverse symptoms of cancer and chemotherapy are a major health burden; chief among these is pain, with opioids including transdermal fentanyl the mainstay of treatment. Innate immune activation has been implicated generally in pain, opioid analgesia, cognitive dysfunction, and sickness type symptoms reported by cancer patients. We aimed to determine if genetic polymorphisms in neuroimmune activation pathways alter the serum fentanyl concentration-response relationships for pain control, cognitive dysfunction, and other adverse symptoms, in cancer pain patients. Cancer pain patients (468) receiving transdermal fentanyl were genotyped for 31 single nucleotide polymorphisms in 19 genes: CASP1, BDNF, CRP, LY96, IL6, IL1B, TGFB1, TNF, IL10, IL2, TLR2, TLR4, MYD88, IL6R, OPRM1, ARRB2, COMT, STAT6 and ABCB1. Lasso and backward stepwise generalised linear regression were used to identify non-genetic and genetic predictors, respectively, of pain control (average Brief Pain Inventory < 4), cognitive dysfunction (Mini-Mental State Examination ≤ 23), sickness response and opioid adverse event complaint. Serum fentanyl concentrations did not predict between-patient variability in these outcomes, nor did genetic factors predict pain control, sickness response or opioid adverse event complaint. Carriers of the MYD88 rs6853 variant were half as likely to have cognitive dysfunction (11/111) than wild-type patients (69/325), with a relative risk of 0.45 (95% CI: 0.27 to 0.76) when accounting for major non-genetic predictors (age, Karnofsky functional score). This supports the involvement of innate immune signalling in cognitive dysfunction, and identifies MyD88 signalling pathways as a potential focus for predicting and reducing the burden of cognitive dysfunction in cancer pain patients.

The Rapid Cognitive Screen (RCS): A Point-of-Care Screening for Dementia and Mild Cognitive Impairment

OBJECTIVES

There is a need for a rapid screening test for mild cognitive impairment (MCI) and dementia to be used by primary care physicians. The Rapid Cognitive Screen (RCS) is a brief screening tool (< 3 min) for cognitive dysfunction. RCS includes 3-items from the Veterans Affairs Saint Louis University Mental Status (SLUMS) exam: recall, clock drawing, and insight. Study objectives were to: 1) examine the RCS sensitivity and specificity for MCI and dementia, 2) evaluate the RCS predictive validity for nursing home placement and mortality, and 3) compare the RCS to the clock drawing test (CDT) plus recall.

METHODS

Patients were recruited from the St. Louis, MO Geriatric Research Education and Clinical Center (GRECC), Veterans Affairs Medical Center (VAMC) hospitals (study 1) or the Saint Louis University Geriatric Medicine and Psychiatry outpatient clinics (study 2). Study 1 participants (N=702; ages 65-92) completed cognitive evaluations and 76% (n=533/706) were followed up to 7.5 years for nursing home placement and mortality. Receiver operator characteristic (ROC) curves were computed to determine sensitivity and specificity for MCI (n=180) and dementia (n=82). Logistic regressions were computed for nursing home placement (n=31) and mortality (n=176). Study 2 participants (N=168; ages 60-90) completed the RCS and SLUMS exam. ROC curves were computed to determine sensitivity and specificity for MCI (n=61) and dementia (n=74).

RESULTS

RCS predicted dementia and MCI in study 1 with optimal cutoff scores of ≤ 5 for dementia (sensitivity=0.89, specificity=0.94) and ≤ 7 for MCI (sensitivity=0.87, specificity=0.70). The CDT plus recall predicted dementia and MCI in study 1 with optimal cutoff scores of ≤ 2 for dementia (sensitivity=0.87, specificity=0.85) and ≤ 3 for MCI (sensitivity=0.62, specificity=0.62). Higher RCS scores were protective against nursing home placement and mortality. The RCS predicted dementia and MCI in study 2.

CONCLUSIONS

The 3-item RCS exhibits good sensitivity and specificity for the detection of MCI and dementia, and higher cognitive function on the RCS is protective against nursing home placement and mortality. The RCS may be a useful screening instrument for the detection of cognitive dysfunction in the primary care setting.

Feasibility and validity of the self-administered computerized assessment of mild cognitive impairment with older primary care patients

We investigated whether a validated computerized cognitive test, the Computerized Assessment of Mild Cognitive Impairment (CAMCI), could be independently completed by older primary care patients. We also determined the optimal cut-off for the CAMCI global risk score for mild cognitive impairment against an independent neuropsychological reference standard. All eligible patients aged 65 years and older, seen consecutively over 2 months by 1 family practice of 13 primary care physicians, were invited to participate. Patients with a diagnosis or previous work-up for dementia were excluded. Primary care physicians indicated whether they, the patient, or family had concerns about each patient's cognition. A total of 130 patients with cognitive concerns and a matched sample of 133 without cognitive concerns were enrolled. The CAMCI was individually administered after instructions to work independently. Comments were recorded verbatim. A total of 259 (98.5%) completed the entire CAMCI. Two hundred and forty-one (91.6%) completed it without any questions or after simple acknowledgment of their question. Lack of computer experience was the only patient characteristic that decreased the odds of independent CAMCI completion. These results support the feasibility of using self-administered computerized cognitive tests with older primary care patients, given the increasing reliance on computers by people of all ages. The optimal cut-off score had a sensitivity of 80% and specificity of 74%.

The Brief Cognitive Status Examination (BCSE): Comparing Diagnostic Utility and Equating Scores to the Mini-Mental State Examination (MMSE)

The study purpose was to compare the diagnostic utility of the Brief Cognitive Status Exam (BCSE) to that of the Mini-Mental State Examination (MMSE) and to develop equated scores to facilitate comparisons. One hundred and eighty-two patients underwent cognitive evaluation and were placed into three groups: dementia (DEM), cognitive impairment, no dementia (CIND), and no cognitive impairment (NCI). One hundred and eighty-two healthy controls from the BCSE standardization sample served as a comparison group. On both measures, the DEM group obtained significantly lower scores than the other two groups, and the CIND group scored significantly lower than the NCI group. The BCSE was more sensitive in all clinical groups, although at extremely low scores, the two tests displayed similar sensitivity. Results indicate the BCSE has diagnostic utility as a cognitive screening measure in a mixed clinical sample and is more sensitive at detecting cognitive impairment, particularly milder levels, than the MMSE.

Scaling Cognitive Domains of the Montreal Cognitive Assessment: An Analysis Using the Partial Credit Model

The psychometric properties of the Montreal Cognitive Assessment (MoCA) were examined by using the Partial Credit Model. The study sample included 897 participants who were distributed into two main subgroups: (I) the clinical group (90 patients with Mild Cognitive Impairment, 90 patients with Alzheimer's disease, 33 patients with Frontotemporal Dementia, and 34 patients with Vascular dementia, whose diagnoses were previously established according to a consensus that was reached by a multidisciplinary team, based on the international criteria) and (II) the healthy group (composed of 650 cognitively healthy community dwellers). The results show (i) an overall good fit for both the items and the persons' values, (ii) high variability for the cognitive performance level of the cognitive domains (ranging between 1.90 and -3.35, where "Short-term Memory" was the most difficult item and "Spatial Orientation" was the easiest item) and between the subjects on the scale, (iii) high reliability for the estimation of the persons' values, (iv) good discriminant validity and high diagnostic utility, and (v) a minimal differential item functioning effect related to of pathology, gender, age, and educational level. MoCA and its cognitive domains are suitable measures to use for screening the cognitive status of cognitively healthy subjects and patients with cognitive impairment.

An investigation of the efficiency of the mini-Kingston standardized cognitive assessment-revised in classifying patients according to DSM-5 major and mild neurocognitive disorders due to possible Alzheimer's disease

BACKGROUND

The aim of this study was to examine the efficiency of the mini-Kingston standardized cognitive assessment-revised (mini-KSCAr) in classifying patients according to DSM-5 major and mild neurocognitive disorders (NCD) due to possible Alzheimer's disease (AD).

METHODS

Files of 85 individuals who were tested on the Kingston standardized cognitive assessment-revised were reviewed and scores were calculated for the mini-KSCAr. Medical history, psychiatric and physical status, basic and instrumental activities of daily living, as well as scores on the Cambridge cognitive examination-revised (CAMCOG-R), and the clinical dementia rating (CDR) scale were used to establish DSM-5 diagnoses of major or mild neurocognitive disorders (NCD) due to possible AD or no cognitive decline. All participants were tested on the Mini-Mental State Examination (MMSE) and the clock drawing test (CDT), and a subset (N = 28) were also tested on three well-known memory tasks.

RESULTS

Scores on the MMSE, CDT, and mini-KSCAr differed across groups, but only the mini-KSCAr significantly distinguished each group from the other two. The mini-KSCAr showed better sensitivity, specificity, and likelihood ratios (LRs) than did the MMSE and the CDT. A regression analysis revealed that the mini-KSCAr accounted for almost half of the variance in memory performance, whereas the MMSE and the CDT contributed nothing to this prediction once the mini-KSCAr was used.

CONCLUSIONS

The mini-KSCAr is an efficient instrument for the diagnosis of DSM-5 major and mild NCD due to possible AD in a specialized psychogeriatric setting, and its utility is greater than that of the MMSE and the CDT.

Cognitive stimulation of executive functions in mild cognitive impairment: specific efficacy and impact in memory

Executive functions play an important role in the maintenance of autonomy in day-to-day activities. Nevertheless, there is little research into specific cognitive training for Mild Cognitive Impairment (MCI). We present the results of a program which aims to teach specific strategies and metacognitive abilities in order for patients to be able to carry out attentional and executive tasks. Two groups (A and B) were compared in a cross-over design. After the first evaluation, Group A (but not B) participated in a six month cognitive stimulation program. After a second assessment, only Group B received treatment and then a final evaluation was carried out on both groups. The results show that: i) both groups improved their performance as an effect of training; ii) improvements generalized to memory and general cognitive tasks; iii) in the interval without training, Group B's performance worsened and iv) Group A partially maintained their results over time.

Validation of the Chinese version of Addenbrooke's cognitive examination-revised for screening mild Alzheimer's disease and mild cognitive impairment

BACKGROUND/AIMS

As a suitable test to screen for Alzheimer's disease (AD) or mild cognitive impairment (MCI), studies to validate the Chinese version of Addenbrooke's Cognitive Examination-Revised (ACE-R) are rare.

METHODS

A total of 151 subjects were recruited and the neuropsychological assessments were employed. One-way analysis of variance and Bonferroni correction were used to compare scores of different psychometric scales. Intraclass correlation coefficient (ICC) and Cronbach's coefficient α were used to evaluate the reliability of psychometric scales. The validity of ACE-R to screen for mild AD and amnestic subtype of MCI (a-MCI) was assessed by receiver operating characteristic (ROC) curves.

RESULTS

The Chinese ACE-R had good reliability (inter-rater ICC = 0.994; test-retest ICC = 0.967) as well as reliable internal consistency (Cronbach's coefficient α = 0.859). With its cutoff of 67/68, the sensitivity (0.920) and specificity (0.857) were lower than for the Mini-Mental State Examination (MMSE) cutoff (sensitivity 1.000 and specificity 0.937) to screen for mild AD. However, the sensitivity of ACE-R to screen for a-MCI was superior to the MMSE with a cutoff of 85/86. The specificity of ACE-R was lower than that of the MMSE to screen for a-MCI. The area under the ROC curve of ACE-R was much larger than that of the MMSE (0.836 and 0.751) for detecting a-MCI rather than mild AD.

CONCLUSION

The Chinese ACE-R is a reliable assessment tool for cognitive impairment. It is more sensitive and accurate in screening for a-MCI rather than for AD compared to the MMSE.

Correlational analysis of 5 commonly used measures of cognitive functioning and mental status: an update

There are numerous measures for detecting the presence of dementia and quantifying its severity and progression. We analyzed the relations between scores on 5 commonly used measures (Mini-Mental State Examination, Montreal Cognitive Assessment, Alzheimer's Disease Assessment Scale-Cognitive Subscale, Activities of Daily Living Scale, and Global Deterioration Scale) of 101 successive admissions to a memory clinic. Patients were included in the analysis only if they received a diagnosis of mild cognitive impairment (MCI) due to Alzheimer's disease (AD) pathophysiological process or probable AD and if they received all measures. Regression analysis yielded 20 linear equations that allow for conversion between test scores on any 2 measures. Further, participants were grouped by MMSE scores with regard to level of disease severity, allowing for the creation of a quick reference table for estimating an approximate score range between measures. Results from this study provide a useful tool for clinicians when comparing between multiple different instruments that measure the mental status and functional ability of individuals with AD and MCI due to AD pathology.

Multimodal retinal vessel analysis in CADASIL patients

PURPOSE

To further elucidate retinal findings and retinal vessel changes in Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) patients by means of high resolution retinal imaging.

METHODS

28 eyes of fourteen CADASIL patients and an equal number of control subjects underwent confocal scanning laser ophthalmoscopy (cSLO), spectral-domain optical coherence tomography (SD-OCT), retinal nerve fibre layer (RNFL) measurements, fluorescein and indocyanine angiography. Three vessel measurement techniques were applied: RNFL thickness, a semiautomatic software tool based on cSLO images and manual vessel outlining based on SD-OCT.

RESULTS

Mean age of patients was 56.2 ± 11.6 years. Arteriovenous nicking was present in 22 (78.6%) eyes and venous dilation in 24 (85.7%) eyes. Retinal volume and choroidal volume were 8.77 ± 0.46 mm(3) and 8.83 ± 2.24 mm(3). RNFL measurements showed a global increase of 105.2 µm (

CONTROL GROUP

98.4 µm; p = 0.015). Based on semi-automatic cSLO measurements, maximum diameters of arteries and veins were 102.5 µm (106.0 µm; p = 0.21) and 128.6 µm (124.4 µm; p = 0.27) respectively. Manual SD-OCT measurements revealed significantly increased mean arterial 138.7 µm (125.4 µm; p<0.001) and venous 160.0 µm (146.9; p = 0.003) outer diameters as well as mean arterial 27.4 µm (19.2 µm; p<0.001) and venous 18.3 µm (15.7 µm; p<0.001) wall thicknesses in CADASIL patients.

CONCLUSIONS

The findings reflect current knowledge on pathophysiologic changes in vessel morphology in CADASIL patients. SD-OCT may serve as a complementary tool to diagnose and follow-up patients suffering from cerebral small-vessel diseases.

Diagnostic tools for alzheimer's disease dementia and other dementias: an overview of diagnostic test accuracy (DTA) systematic reviews

BACKGROUND

Dementia includes a group of neurodegenerative disorders characterized by progressive loss of cognitive function and a decrease in the ability to perform activities of daily living. Systematic reviews of diagnostic test accuracy (DTA) focus on how well the index test detects patients with the disease in terms of figures such as sensitivity and specificity. Although DTA reviews about dementia are essential, at present there is no information about their quantity and quality.

METHODS

We searched for DTA reviews in MEDLINE (1966-2013), EMBASE (1980-2013), The Cochrane Library (from its inception until December 2013) and the Database of Abstracts of Reviews of Effects (DARE). Two reviewers independently assessed the methodological quality of the reviews using the AMSTAR measurement tool, and the quality of the reporting using the PRISMA checklist. We describe the main characteristics of these reviews, including basic characteristics, type of dementia, and diagnostic test evaluated, and we summarize the AMSTAR and PRISMA scores.

RESULTS

We selected 24 DTA systematic reviews. Only 10 reviews (41.6%), assessed the bias of included studies and few (33%) used this information to report the review results or to develop their conclusions Only one review (4%) reported all methodological items suggested by the PRISMA tool. Assessing methodology quality by means of the AMSTAR tool, we found that six DTA reviews (25%) pooled primary data with the aid of methods that are used for intervention reviews, such as Mantel-Haenszel and separate random-effects models (25%), while five reviews (20.8%) assessed publication bias by means of funnel plots and/or Egger's Test.

CONCLUSIONS

Our assessment of these DTA reviews reveals that their quality, both in terms of methodology and reporting, is far from optimal. Assessing the quality of diagnostic evidence is fundamental to determining the validity of the operating characteristics of the index test and its usefulness in specific settings. The development of high quality DTA systematic reviews about dementia continues to be a challenge.

Cognitive and emotional dysfunction in mild cognitive impairment

Although mild cognitive impairment (MCI) is a widely accepted construct both clinically and in the research literature, it remains a heterogeneous condition that varies in presentation and prognosis. This article first reviews the evolution of the diagnosis of MCI, followed by examination of pros and cons of cognitive assessments commonly used to assess for MCI. Emotional changes commonly seen in MCI are also reviewed. Finally, the relation between cognitive and emotional dysfunction is examined, including a discussion of specific psychological symptoms seen in subtypes of MCI, and how the presence of neuropsychiatric symptoms may affect the risk for progression to dementia.

Cognitive dysfunction following desflurane versus sevoflurane general anesthesia in elderly patients: a randomized controlled trial

As life expectancy increases, more patients ≥65 years undergo general anesthesia. Anesthetic agents may contribute to postoperative cognitive dysfunction, and incidence may differ with anesthetic agents or intraoperative anesthesia depth. Responses to anesthetic adjuvants vary among elderly patients. Processed electroencephalography guidance of anesthetic may better ensure equivalent cerebral suppression. This study investigates postoperative cognitive dysfunction differences in elderly patients given desflurane or sevoflurane using processed electroencephalography guidance.

IRB approved, randomized trial enrolled consenting patients ≥65 years scheduled for elective surgery requiring general anesthesia ≥120 minute duration. After written informed consent, patients were randomly assigned to sevoflurane or desflurane. No perioperative benzodiazepines were administered. Cognitive impairment was measured by an investigator blinded to group assignment using mini-Mental Status Examination (MMSE) at baseline; 1, 6, and 24 hours after the end of anesthesia. Mean arterial pressure was maintained within 20% of baseline. Anesthetic dose was adjusted to maintain moderate general anesthesia per processed electroencephalograpy (Patient State Index 25 to 50). The primary outcome measure was intergroup difference in MMSE change 1 hour after anesthesia (median; 95% confidence interval).

110 patients consented; 26 were not included for analysis (no general anesthesia; withdrew consent; baseline MMSE abnormality; inability to perform postoperative MMSE; data capture failure); 47 sevoflurane and 37 desflurane were analyzed. There were no significant differences in patient characteristics; intraoperative mean blood pressure (desflurane 86.4; 81.3 to 89.6 versus sevoflurane 82.5; 80.2 to 86.1 mmHg; p = 0.42) or Patient State Index (desflurane 41.9; 39.0 to 44.0 versus sevoflurane 41.0; 37.5 to 44.0; p = 0.60) despite a lower MAC fraction in desflurane (0.82; 0.77 to 0.86) versus sevoflurane (0.96; 0.91 to 1.03; p < 0.001). MMSE decreased 1 hour after anesthesia (p < 0.001). The decrease at one hour was larger in sevoflurane (−2.5; −3.3 to −1.8) than desflurane (−1.3; −2.2 to −0.5; p = 0.03). MMSE returned to baseline by 6 hours after anesthesia.

Can smartphones enhance telephone-based cognitive assessment (TBCA)?

TBCA has emerged to solve the limitations of administering cognitive assessments face-to-face. The recent development of telephones and knowledge advances in the area of cognitive impairment may affect the development of TBCA. The purpose of this paper is to discuss how smartphones can be used to enhance the applicability of TBCA, which has previously been administered by conventional telephone. This paper will first review, describe and critique the existing TBCA instruments. It will then discuss the recent developments in tele-technology, the popularity of tele-technology among the elderly, potential benefits and challenges in using smartphones for cognitive assessment, and possible future developments in this technology. In the systematic review, eighteen TBCA instruments were identified. They were found to be valid in differentiating between people with and without dementia. TBCA was previously found to be launched on a conventional telephone platform. The advances in understanding of cognitive impairment may demand that telephones be equipped with more advanced features. Recently, the development and penetration of smartphones among the elderly has been rapid. This may allow the smartphone to enhance its TBCA applicability by overcoming the limitations of the conventional telephone, rendering the TBCA more efficient in addressing the increasing demand and complexity of cognitive assessments in the future. However, more research and technology developments are needed before smartphones can become a valid platform for TBCA.

Electrophysiological correlates of amnestic mild cognitive impairment in a simon task

Amnestic mild cognitive impairment (aMCI) represents a prodromal stage of Alzheimer`s disease (AD), especially when additional cognitive domains are affected (Petersen et al., 2009). Thus, single-domain amnestic MCI (sdaMCI) and multiple-domain-amnestic MCI (mdaMCI) biomarkers are important for enabling early interventions to help slow down progression of the disease. Recording event-related potentials (ERPs) is a non-invasive and inexpensive measure of brain activity associated with cognitive processes, and it is of interest from a clinical point of view. The ERP technique may also be useful for obtaining early sdaMCI and mdaMCI biomarkers because ERPs are sensitive to impairment in processes that are not manifested at behavioral or clinical levels. In the present study, EEG activity was recorded in 25 healthy participants and 30 amnestic MCI patients (17 sdaMCI and 13 mdaMCI) while they performed a Simon task. The ERPs associated with visuospatial (N2 posterior-contralateral - N2pc -) and motor (lateralized readiness potential - LRP -) processes were examined. The N2pc amplitude was smaller in participants with mdaMCI than in healthy participants, which indicated a decline in the correlates of allocation of attentional resources to the target stimulus. In addition, N2pc amplitude proved to be a moderately good biomarker of mdaMCI subtype (0.77 sensitivity, 0.76 specificity). However, the LRP amplitude was smaller in the two MCI groups (sdaMCI and mdaMCI) than in healthy participants, revealing a reduction in the motor resources available to execute the response in sdaMCI and mdaMCI patients. Furthermore, the LRP amplitude proved to be a valid biomarker (0.80 sensitivity, 0.92 specificity) of both amnestic MCI subtypes.

Should the mini-mental state examination be retired?

INTRODUCTION

Short cognitive tests are routinely used in clinical practice to detect and screen for cognitive impairment and dementia. These cognitive tests should meet minimum criteria for both applicability and psychometric qualities.

DEVELOPMENT

The Mini-Mental State Examination (MMSE) is the most frequently applied short cognitive test, and the article introducing it remains a milestone in the history of medicine. Its main advantages are its widespread use and the extensive empirical evidence that supports it. However, the MMSE has important shortcomings, including lack of standardisation, its lack of suitability for illiterate subjects, the considerable effect of socio-educational variables on results, and its limited effectiveness for detecting cognitive impairment. Lastly, since the test is copyright-protected, using it is necessarily either costly or fraudulent. Newer available instruments do not share these shortcomings and have demonstrated greater diagnostic accuracy for detecting cognitive impairment and dementia, as well as being more cost-effective than the MMSE CONCLUSION: It is time to acknowledge the MMSE's important role in the history of medicine and grant it a deserved and honourable retirement. Its place will be taken by more effective instruments that require less time, are user-friendly and free of charge, can be applied to all individuals, and yield more equitable outcomes.