Rey verbal learning test is a useful tool for differential diagnosis in the preclinical phase of Alzheimer's disease: comparison with mild cognitive impairment and normal aging

OBJECTIVE: To confirm that performance in verbal learning and memory test (Rey's Auditory Verbal Learning Test-RAVLT) is a helpful early neuropsychological marker of dementia of Alzheimer's type (DAT). METHODS: RAVLT was administered as part of a more extensive neuropsychological battery at baseline evaluation in 116 unselected patients referred by subjective memory complaints (SMC). Patients were followed longitudinally for 2 years (average interval of 27.7+/-4 months). Seventy patients were included in the study: 27 developed probable DAT; 17 were diagnosed as cognitively normal persons and 26 were diagnosed with Mild Cognitive Impairment (MCI). Remaining patients abandoned or they did not meet the criteria for DAT, MCI or control. Performance on RAVLT at the baseline evaluation was compared between groups. RESULTS: Patients diagnosed two years later with probable DAT showed lower results, more frequently performed a score of zero at the delayed recall test (Trial 6) and had a percentage of forgetting (difference between Trials 5 and 6) higher than 75%. Score at delayed recall test and percentage of forgetting correlated with functional scales such as MMSE, Geriatric Depression Screening, Informant Questionnaire and Blessed's Dementia Rating. CONCLUSIONS: RAVLT could help to identify those patients with SMC who would progress to DAT over a few years, and also to differentiate between the preclinical phase of Alzheimer's disease, mild cognitive impairment and normal aging. A score of zero at the delayed recall test or a percentage of forgetting > or =75% in patients with SMC is suggestive of probable DAT in the future.     

The Montreal Cognitive Assessment is superior to the Mini-Mental State Examination in detecting patients at higher risk of dementia

ABSTRACT Background: To examine the discriminant validity of the Montreal Cognitive Assessment (MoCA) and the Mini-Mental State Examination (MMSE) in detecting patients with cognitive impairment at higher risk for dementia at a memory clinic setting. Methods: Memory clinic patients were administered the MoCA, MMSE, and a comprehensive formal neuropsychological battery. Mild cognitive impairment (MCI) subtypes were dichotomized into two groups: single domain-MCI (sd-MCI) and multiple domain-MCI (md-MCI). Area under the receiver operating characteristic curve (ROC) analysis was used to compare the discriminatory ability of the MoCA and the MMSE. Results: Two hundred thirty patients were recruited, of which 136 (59.1%) were diagnosed with dementia, 61 (26.5%) with MCI, and 33 (14.3%) with no cognitive impairment (NCI). The majority of MCI patients had md-MCI (n = 36, 59%). The MoCA had significantly larger AUCs than the MMSE in discriminating md-MCI from the lower risk group for incident dementia (NCI and sd-MCI) [MoCA 0.92 (95% CI, 0.86-0.98) vs. MMSE 0.84 (95% CI, 0.75-0.92), p = 0.02). At their optimal cut-off points, the MoCA (19/20) remained superior to the MMSE (23/24) in detecting md-MCI [sensitivity: 0.83 vs. 0.72; specificity: 0.86 vs. 0.83; PPV: 0.79 vs. 0.72; NPV: 0.89 vs. 0.83; correctly classified: 85.1% vs. 78.7%]. Conclusion: The MoCA is superior to the MMSE in the detection of patients with cognitive impairment at higher risk for incident dementia at a memory clinic setting.     

Identifying patients at high and low risk of cognitive decline using Rey Auditory Verbal Learning Test among middle-aged memory clinic outpatients

OBJECTIVES: To investigate whether application of cutoff levels in an episodic memory test (Rey Auditory Verbal Learning Test, RAVLT) is a useful method for identifying patients at high and low risk of cognitive decline and subsequent dementia. METHODS: 224 patients with memory complaints (mean age = 60.7 years, mean MMSE = 28.2) followed-up at a memory clinic over approximately 3 years were assigned retrospectively to one of three memory groups from their baseline results in RAVLT [severe (SIM), moderate (MIM) or no impairment (NIM)]. These groups were investigated regarding cognitive decline. RESULTS: Patients assigned to SIM showed significant cognitive decline and progressed to dementia at a high rate, while a normal performance in RAVLT at baseline (NIM) predicted normal cognition after 3 years. Patients with MIM constituted a heterogeneous group; some patients deteriorated cognitively, while the majority remained stable or improved. CONCLUSIONS: The application of cutoff levels in RAVLT at baseline showed that patients with severely impaired RAVLT performance were at a high risk of cognitive decline and progression to dementia, while patients with normal RAVLT results did not show cognitive decline during 3 years. Furthermore, the initial degree of memory impairment was decisive in the cognitive prognosis 3 years later.     

The role of the Montreal Cognitive Assessment (MoCA) and its memory tasks for detecting mild cognitive impairment

To investigate the role of the Montreal Cognitive Assessment (MoCA) (Beijing version) and its memory tasks on detecting different mild cognitive impairment (MCI) subtypes including amnestic MCI (aMCI) and nonamnestic MCI (naMCI) in memory clinics. A total of 121 patients with MCI and 53 healthy controls were included. Fifty-six aMCI-multiple domains (amMCI), 32 aMCI-single domain (asMCI), and 33 naMCI patients were diagnosed according to extensive cognitive tests. All participants were administered by the Mini Mental State Examination (MMSE) and the MoCA. Patients with amMCI performed worse than patients with asMCI, naMCI, and healthy controls on the MMSE and the MoCA (p <?0.001). The area under the curve (AUC) value for the MoCA when comparing the amMCI and control groups was 0.884 (p?<?0.001), which was superior to that of the MMSE. The AUC value decreased to 0.687 when applied to the naMCI and control groups (p?=?0.007), which was still higher than that of the Rey Auditory Verbal Learning Test (RAVLT) or the Rey-Osterrieth complex figure (ROCF). Delayed free recall or category prompted recall in the MoCA had roles in differentiating asMCI and controls groups with AUC value of 0.717 (p =?0.002) and 0.691 (p =?0.005), respectively. The MoCA is a good screening tool for detecting different types of MCI and is suitable for patients in outpatient clinics.     

Mini-mental State Examination performance in mild cognitive impairment subtypes

BACKGROUND: Diagnosis of mild cognitive impairment (MCI) and its subtypes requires a detailed diagnostic assessment and so may be missed at routine primary-care appointments, since the ordinary dementia screening tests lack sensitivity owing to ceiling effects, especially in highly educated subjects. METHODS: The study was undertaken using a cross-sectional assessment of 112 elderly subjects (mean age 67.96+/-5.77 years, and mean education level of 12.8+/-5.7 years) with a semi-structured interview and a neuropsychological battery. RESULTS: MCI patients did not differ from controls on total MMSE scores (p=0.212). Nevertheless, MCI patients showed worse performance than controls on the verbal memory task (p=0.012), and "drawing a pentagon" (p=0.03). Amnestic MCI patients performed worse only on the "three-word recall" task (p=0.013); non-amnestic MCI patients performed worse on the "three-stage command" task (p=0.001); and multiple-domain MCI patients performed worse on the "drawing a pentagon" task (p=0.001) and had a trend toward performing poorly on the 'three word recall' task (p=0.06). CONCLUSION: The analysis of MMSE subtest scores, in addition to MMSE total scores, may increase the sensitivity of the MMSE test in screening for MCI and its subtypes.     

The validity of brief screening cognitive instruments in the diagnosis of cognitive impairment and dementia after first-ever stroke

INTRODUCTION: Brief cognitive tests such as the Mini-mental State Examination (MMSE) and the Informant Questionnaire for Cognitive Decline in the Elderly (IQCODE) have been used to detect cognitive impairment and dementia in studies of stroke patients. However, there are few data on their validity for such use. We have evaluated their validity in detecting cognitive impairment not dementia (CIND) and dementia in a community-based sample of first-ever stroke patients. METHODS: The standardized MMSE (S-MMSE) and the 16-item IQCODE were administered to 79 patients 1 year after a first-ever stroke. CIND and dementia were diagnosed independently using a comprehensive cognitive battery. The performances of the two tests were evaluated using receiver operating characteristic (ROC) analyses. Combined performance was evaluated when their scores were used in parallel (the "or rule"), in series (the "and rule") or as a weighted sum (the "weighted sum rule"). RESULTS: Both tests were extremely poor at detecting CIND individually and in combination. For dementia, at traditional cut-points, the S-MMSE (< or =23) was insensitive (0.50, 95% CI 0.16-0.84) and the IQCODE (> or =3.30) nonspecific (0.63, 95% CI 0.51-0.75). An acceptable balance between sensitivity and specificity was achieved for dementia using the "or rule" combination, but with only modest positive predictive value. CONCLUSIONS: The S-MMSE and the IQCODE were individually poor at detecting CIND and dementia after a nonaphasic first-ever stroke. The combination was useful in detecting dementia but it does not replace the need for detailed neuropsychological tests.     

Development and assessment of a composite score for memory in the Alzheimer’s Disease Neuroimaging Initiative (ADNI)

We sought to develop and evaluate a composite memory score from the neuropsychological battery used in the Alzheimer’s Disease (AD) Neuroimaging Initiative (ADNI). We used modern psychometric approaches to analyze longitudinal Rey Auditory Verbal Learning Test (RAVLT, 2 versions), AD Assessment Schedule - Cognition (ADAS-Cog, 3 versions), Mini-Mental State Examination (MMSE), and Logical Memory data to develop ADNI-Mem, a composite memory score. We compared RAVLT and ADAS-Cog versions, and compared ADNI-Mem to RAVLT recall sum scores, four ADAS-Cog-derived scores, the MMSE, and the Clinical Dementia Rating Sum of Boxes. We evaluated rates of decline in normal cognition, mild cognitive impairment (MCI), and AD, ability to predict conversion from MCI to AD, strength of association with selected imaging parameters, and ability to differentiate rates of decline between participants with and without AD cerebrospinal fluid (CSF) signatures. The second version of the RAVLT was harder than the first. The ADAS-Cog versions were of similar difficulty. ADNI-Mem was slightly better at detecting change than total RAVLT recall scores. It was as good as or better than all of the other scores at predicting conversion from MCI to AD. It was associated with all our selected imaging parameters for people with MCI and AD. Participants with MCI with an AD CSF signature had somewhat more rapid decline than did those without. This paper illustrates appropriate methods for addressing the different versions of word lists, and demonstrates the additional power to be gleaned with a psychometrically sound composite memory score.     

Improvement of Screening Accuracy of Mini-Mental State Examination for Mild Cognitive Impairment and Non-Alzheimer's Disease Dementia by Supplementation of Verbal Fluency Performance

Objective

This study aimed to investigate whether the supplementation of Verbal Fluency: Animal category test (VF) performance can improve the screening ability of Mini-Mental State Examination (MMSE) for mild cognitive impairment (MCI), dementia and their major subtypes.

Methods

Six hundred fifty-five cognitively normal (CN), 366 MCI [282 amnestic MCI (aMCI); 84 non-amnestic MCI (naMCI)] and 494 dementia [346 Alzheimer''s disease (AD); and 148 non-Alzheimer''s disease dementia (NAD)] individuals living in the community were included (all aged 50 years and older) in the study.

Results

The VF-supplemented MMSE (MMSE+VF) score had a significantly better screening ability for MCI, dementia and overall cognitive impairment (MCI plus dementia) than the MMSE raw score alone. MMSE+VF showed a significantly better ability than MMSE for both MCI subtypes, i.e., aMCI and naMCI. In the case of dementia subtypes, MMSE+VF was better than the MMSE alone for NAD screening, but not for AD screening.

Conclusion

The results support the usefulness of VF-supplementation to improve the screening performance of MMSE for MCI and NAD.     

Evolution of cognitive deficits and conversion to dementia in patients with mild cognitive impairment: a very-long-term follow-up study

Ten patients with mild cognitive impairment (MCI) underwent extensive neuropsychological evaluation at 12-monthly intervals for a minimum of 6 years. All 10 patients declined and 5 have now died. The onset of dementia, as defined by a fall in global cognitive function (MMSE <24) or activities of daily living (Clinical Dementia Rating Scale; CDR) ranged from 1 to 8 years with generally good concordance between these measures. The rate of decline on the MMSE was highly variable ranging from 0.86 to 2.83 points per year. Other than a consistent impairment on tests of episodic memory and category fluency (8 out of 10), other early cognitive deficits were difficult to define and tended to be unstable in the early stages. Impairment of semantic memory, visuo-spatial and attentional abilities eventually developed but the sequence of deficit acquisition was heterogeneous. These findings are discussed in the light of current views of MCI. Amnestic MCI may not be an accurate concept unless semantic memory impairment is also considered as an integral core deficit. Full-blown dementia may take many years to develop in patients with MCI but was a universal feature in this study.     

Vascular risk factors and intensity of cognitive dysfunction in MCI

Patients with Mild Cognitive Impairment (MCI) have a greater risk of developing dementia than general population. Lots of evidence suggests that cardiovascular risk factors appear more often in the MCI than in general population The aim of this study was to evaluate association between cardiovascular risk factors and intensity of cognitive impairment in MCI patients. We evaluated 24 MCI patients (9 women and 15 men) fulfilling Mayo Clinic Group Criteria. Taking under consideration presence of cardiovascular diseases patients were divided into two groups: first group (n=16) MCI with cardiovascular diseases and second group (n=8) MCI without cardiovascular disorders. Cognitive functions were assessed by neuropsychological tests battery including MMSE, Clock Drawing Test, Trail Making Test (TMT), Verbal Fluency Test with letters FAS, Auditory Verbal Learning Test (AVLT). In the MCI group with vascular risk factors we have found more distinct dysfunction of learning new information, recall and short-term memory than in MCI patients without vascular pathology. In conclusion we may suggest that more distinct cognitive deficit may indicate higher risk of developing dementia, that is why patients with MCI should be under special supervision, with at least annual neuropsychological evaluation.     

Alcohol consumption and transition of mild cognitive impairment to dementia

Aim:  Mild cognitive impairment (MCI) is a prodrome for dementia. Alcohol drinking patterns may affect cognitive functions and the effects may accumulate to a significant level at an advanced age. This study investigated the relationship between alcohol consumption and risks for dementia in a cohort of elderly patients with MCI.
Methods:  Patients with suspected cognitive impairment were screened. One hundred and seventy-six patients who met the MCI criteria were enrolled. Lifetime and daily alcohol consumptions were assessed at baseline using a self-report questionnaire answered by patients and their caregivers. Patients were classified according to alcohol consumptions as abstainers, light–moderate and heavy drinkers. Global cognitive functions were assessed periodically with Mini-Mental State Examination (MMSE). Enrolled patients were followed for 2 years.
Results:  Of the 176 patients diagnosed as having MCI, 15 (8.5%) died, 13 (7.4%) were lost to follow up, and 66 (37.5%) developed dementia during follow up. Light–moderate alcohol drinkers had better MMSE performance than abstainers ( P  < 0.05) and heavy drinkers ( P  < 0.01) 2 years after MCI diagnosis. Patients who consumed a total of ≤300 kg alcohol prior to MCI diagnosis had less cognitive decline than patients who consumed no ( P  < 0.05) or >300 kg alcohol ( P  < 0.01). Heavy drinkers had a higher risk for dementia than abstainers ( P  < 0.05) and light–moderate drinkers ( P  < 0.05) 2 years after MCI diagnosis.
Conclusions:  A J-shaped relationship may exist between alcohol consumption and cognitive decline in MCI patients. Light–moderate alcohol drinking may be associated with decreased risks for dementia in elderly patients with MCI.     

Cerebral Amyloid Positivity Prediction Models Using Clinical Data in Subjects With Mild Cognitive Impairment and Dementia

ObjectiveDue to high cost of amyloid imaging, its use of amyloid imaging to confirm amyloid pathology is limited in clinical practice. It is of importance to develop a model to predict cerebral amyloid positivity using clinical data obtained from a memory clinic. MethodsA total of 410 participants who had symptom of subjective cognitive decline and underwent amyloid PET and apolipoprotein ε (APOE) genotyping were retrospectively enrolled from January 2016 to January 2019. Models for cerebral amyloid positivity prediction were developed in all subjects, mild cognitive impairment (MCI) subjects, and Alzheimer’s disease (AD) dementia subjects through multivariate logistic regression analysis. The performance of the models was assessed using receiver operating characteristic (ROC) curve analysis and the area under the curve (AUC) values. ResultsAge, sex, years of education, body mass index (BMI), APOE4, and mini mental state examination score (MMSE) were selected for the final model for all subjects. The AUC value of the ROC curve was 0.775. Age, sex, years of education, BMI, and APOE4 were selected for the final model for MCI subjects. The AUC value was 0.735. Age, sex, years of education, BMI, APOE4, MMSE, and history of hypertension were selected for the final model for AD dementia subjects. The AUC value was 0.845. ConclusionThis study found that models using clinical data can predict cerebral amyloid positivity according to cognitive status. These models can be useful as a screening tool predict cerebral amyloid deposition in cognitively impaired patients in a memory clinic.     

CSF levels of heart fatty acid binding protein are altered during early phases of Alzheimer's disease

Heart fatty acid binding protein (HFABP) has been proposed as a putative marker for dementia disorders. To evaluate the value of this protein as an early marker of Alzheimer's disease (AD), we analyzed HFABP level and the classical biomarkers amyloid-β (Aβ)1-42, total tau (t-tau), and phosphorylated tau (p-tau) in cerebrospinal fluid (CSF) of patients with mild cognitive impairment (MCI) followed up for four years (n=41), AD (n=32), and subjects with other neurological diseases without dementia (OND, n=25). HFABP levels were higher in AD patients and in MCI converting to AD (MCI-AD) with respect to OND and to cognitively stable MCI patients (MCI-MCI). The receiver operator characteristics analysis for HFABP alone showed a sensitivity of 87% and a specificity of 81% for AD versus OND (area under the curve, AUC=0.83); sensitivity and specificity were 46% and 94%, respectively, when comparing MCI-MCI versus MCI-AD. CSF HFABP levels showed a strong positive correlation with both t-tau and p-tau. Interestingly, the ratio between HFABP and Aβ1-42 improved the performance in distinguishing AD from OND (sensitivity: 90%; specificity 82%, AUC=0.89), and gave the best accuracy in discriminating MCI-AD from MCI-MCI (sensitivity: 80%; specificity 100%, AUC=0.90). Survival analysis by means of Kaplan-Meier curve showed a significantly higher proportion of MCI patients converting to AD in the group with higher values of HFABP/Aβ1-42 ratio (cut-off=0.7). A significant correlation between HFABP/Aβ1-42 ratio and MMSE annual decrease rate was also documented (p<0.0001). HFABP /Aβ1-42 ratio might be a useful predictor of conversion in MCI patients.     

两种轻度认知损害患者的神经心理学功能比较

背景区别轻度认知损害（mildcognitiveimpairment,MCI）的两种亚型,即遗忘型轻度认知损害（alTlnesticmildcogni—tiveimpairment,aMCI）和小血管型轻度认知损害（MCIassociatedwithsmallvesseldiseases,sv-MCI）将有利于延缓和预防MCI进展为阿尔茨海默病性痴呆和血管性痴呆。目的识别并区分区aMCI与sv-MCI的神经心理学特征。方法从宣武医院神经科门诊就诊患者或在北京社区进行的一项入户调查中选择符合入组标准的被试。根据Pe—tersen诊断标准筛选aMCI患者50例,根据Hachinski诊断标准筛选sv-MCI患者65例。以上两组患者和49名55岁以上没有认知障碍的社区被试一同接受简明精神状态量表（MiniMentalStateExamination,MMSE）检查及画钟测验（ClockDrawingTest,CDT）与听觉词语学习测验（AuditoryVerbalLearningTest,AVLT,评定即刻记忆、延迟回忆和延迟再认能力）。采用单因素方差分析法比较3组被试各项测验的平均得分,如果结果存在明显差异,再进行多个样本两两比较的Tukey法检验。结果aMCI组和SV．MCI组5项测验平均得分均明显低于健康对照组。aMCI组AVLT即刻记忆、延迟回忆和延迟再认测验得分均低于SV．MCI组。在校正了年龄、性别、受教育年限后,上述差异仍旧存在。结论实验结果与既往结果一致,与SV—MCI患者相比,aMCI患者记忆损害更加明显。记忆相关的评估测验,尤其是AVLT,或将有助于区别这两种MCI亚型。     

Neuropsychiatric symptoms in mild cognitive impairment: a population‐based study

Introduction: Few studies have examined neuropsychiatric symptoms in community dwelling older adults with mild cognitive impairment (MCI). In the present study, we compared the prevalence of neuropsychiatric symptoms in older adults with normal cognition, MCI, and dementia in a population‐based sample. Methods: Subjects were selected from the Singapore Longitudinal Ageing study. Normal cognitive function was defined as Clinical Dementia Rating (CDR) global score=0 and Mini‐Mental State Examination (MMSE) total score ≥24. MCI was defined as CDR global score=0.5, and dementia was defined as CDR global score ≥1. Neuropsychiatric Inventory (NPI) was administered on reliable informants for 293 subjects (136 normal, 133 MCI, and 24 dementia). Results: The prevalence of neuropsychiatric symptoms (at lest one symptom) was 5.9% for normal cognition, 12.8% for MCI, and 50% for dementia. The most common neuropsychiatric symptoms in subjects with MCI were depression/dysphoria (6.8%), irritability/lability (3.8%), apathy/indifference (2.3%), and agitation/aggression (2.3%). NPI total score increased with increasing CDR global score (P<0.001). The adjusted mean NPI total score was 0.07 (SEM=0.49) for normal cognition, 0.86 (SEM=0.46) for MCI, and 4.50 (SEM=0.82) for dementia. Discussion: In community dwelling Asian older adults, we found an increasing prevalence of neuropsychiatric symptoms in subjects with normal cognition, MCI and dementia. Further studies with larger samples and strict criteria for MCI in an Asian population should be conducted.     

轻度认知功能障碍患者的神经心理学研究

目的 探讨轻度认知功能障碍(MCI)患者神经心理学的特点. 方法 对42例MCI患者和55例健康对照者进行多项神经心理学检查,包括简易精神状态检查量表(MMSE)、蒙特利尔认知评估量表(MoCA)、临床痴呆评定量表(CDR)、语言流畅性测验(RVR)、韦氏智力测验(WAIS-RC)[包括数字广度测验(DS)、积木测验(BD)、相似性测验]、韦氏记忆测验(WMS-R)(包括逻辑记忆、联想学习、视觉再认、图片回忆)、日常生活能力量表(ADL),比较2组患者上述量表评分和MMSE、MoCA量表各亚项评分的差异.结果 与对照者比较,MCI患者MMSE、MoCA总分和RVR、WAIS-RC、WMS-R分测验,MoCA量表各亚项(地点定向力除外),MMSE量表中计算与注意、延迟回忆两亚项评分较低,差异均有统计学意义(P<0.05).结论 MCI患者不仅记忆受损,其计算与注意力、命名、视空间结构能力、执行功能也可受损,尤以延迟回忆、计算与注意力受损明显.MoCA涵盖了重要的认知领域,能较全面评估MCI患者的认知功能,值的临床推广应用.     

Screening for mild cognitive impairment (MCI) utilizing combined mini-mental-cognitive capacity examinations for identifying dementia prodromes

OBJECTIVE: To test correctness of results when combining Mini-Mental State Examination (MMSE) and Cognitive Capacity Screening Examination (CCSE) for identifying mild cognitive impairment (MCI) among non-demented elderly subjects at risk for developing dementia. METHODS: A retrospective study was conducted among consecutively referred volunteers with memory complaints to a research out-patient clinic. Two cognitive screening tests (MMSE and CCSE) were performed according to established protocol. Resulting combined screening test (termed by acronym as CMC) combined the non-overlapping test items derived from both MMSE and CCSE. Conversion to dementia at follow-up served as the 'gold-standard' for evaluating correctness of CMC for identifying MCI. RESULTS: Of 351 subjects completing cognitive assessments and meeting requirements for study protocol, 84 (23.9%) developed dementia of different types within 3-6 years (3.89 +/- 2.17) of follow-up. Among these, 47 met criteria for probable Alzheimer disease (AD), 22 for probable vascular dementia (VaD), 12 for mixed AD/VaD and three for probable frontotemporal dementia. When final diagnosis of AD was used as the 'gold standard' for testing correctness of MCI identified by cognitive screening tests, sensitivities of MMSE, CCSE and CMC for identifying MCI were relatively 61.0%, 74.3% and 83.1% with minimum specificity set at 80%. When diagnosis of all types of dementia was used as the standard for testing predictive correctness of MCI, CCSE emerged as an optimal MCI screening test. CONCLUSION: Combining the CCSE and MMSE screening tests resulted in higher sensitivity than was achieved by MMSE alone and maintained specificity at comparable levels for identifying MCI. The results confirmed that CMC has optimal correctness and utility as a brief cognitive test for screening MCI as a prodrome for dementia among non-demented elderly populations.     

DemTect: a new, sensitive cognitive screening test to support the diagnosis of mild cognitive impairment and early dementia

OBJECTIVES: To design a new, highly sensitive psychometric screening to identify patients with mild cognitive impairment (MCI) and patients with dementia in the early stages of the disease. METHODS: Five tasks were included in the DemTect: a word list, a number transcoding task, a word fluency task, digit span reverse, and delayed recall of the word list. The normation was performed with 145 healthy control subjects (CG). Furthermore, 97 MCI patients and 121 patients with possible Alzheimer's disease (AD) were tested with the DemTect and the MMSE. Classification rates for both tests were analysed. RESULTS: On the basis of the CG data, age-dependant transformation algorithms for the DemTect subtests were defined, and an education correction was provided for the total transformed score. The patient groups scored significantly below the CG in both the DemTect and the MMSE. Compared to the MMSE, classification rates of the DemTect were superior for both the MCI and the AD group, with high sensitivities of 80% and 100%, respectively. CONCLUSIONS: The DemTect is short (8-10 minutes), easy to administer, and its transformed total score (maximum 18) is independent of age and education. The DemTect helps in deciding whether cognitive performance is adequate for age (13-18 points), or whether MCI (9-12 points) or dementia (8 points or below) should be suspected.     

The reliability and validity of the mini-mental state examination in the elderly croatian population

Aim: The aim of this study was standardization and validation of the Mini-Mental State Examination (MMSE) in the general Croatian aging population. Methods: Three-hundred and forty-four participants underwent the MMSE test, 217 cognitively healthy subjects without neurological and psychiatric disorders and 127 patients with mild cognitive impairment (MCI) or dementia. Results: The optimal cutoff point for screening of the general Croatian population (cognitively healthy vs. MCI and dementia) is 26/27; in the Croatian population aged ≥65 years, the cutoff point is 24/25, whereas for screening of highly educated persons (≥14 years of education) aged ≥65 years a higher cutoff point should be used (26/27). Conclusions: MMSE results when standardized and validated in a certain population might better contribute to recognition of the individuals at risk that should be directed to dementia outpatient clinics.     

Do the ABCS 135 short cognitive screen and its subtests discriminate between normal cognition,mild cognitive impairment and dementia?

BACKGROUND: Cognitive screening instruments are either too long for routine clinical use or not sensitive to distinguish mild cognitive impairment (MCI) from normal cognition (NC) or dementia. OBJECTIVE: To evaluate the sensitivity and specificity of the AB Cognitive Screen (ABCS) and its subtests with a view to improving its ability to differentiate between dementia, MCI and NC. The influence of age and education on sensitivity and specificity is also examined. DESIGN: Cross-sectional study. METHODS: Participants with dementia and MCI were recruited from those presenting to four specialty geriatric clinics in southern Ontario. Participants with NC were recruited from the family and friends of patients. A comprehensive geriatric assessment was done including ABCS, SMMSE and 15 point Geriatric Depression Scale. Analysis of variance and receiver operating characteristic (ROC) curves compared test scores. SMMSE scores were also analysed for comparison purposes. RESULTS: Three hundred and two participants had dementia, 166 had MCI and 174 had NC. ABCS total scores were significantly different between NC and MCI (mean difference 7.1, 1.8-12.5 CI, p = 0.000) while SMMSE scores were not (mean difference 0.5, -0.7-1.7, p < 0.628). Of individual ABCS subtests, verbal fluency and delayed recall were most sensitive to differences between NC and MCI. ROC curve analysis, which presents sensitivity and specificity, showed verbal fluency was better than delayed recall in distinguishing between NC and MCI, among participants 75 years of age or older. CONCLUSION: The AB Cognitive Screen (ABCS) can be administered in 3-5 min. The SMMSE and ABCS total and subtests significantly distinguished between dementia and MCI or NC. Verbal fluency and delayed recall were best at distinguishing between MCI and NC. The analysis illustrates how each subtest contributes to the sensitivity of the ABCS and suggests ways that sensitivity might be improved.