Utility of neuropsychological tests in the diagnosis of amnestic mild cognitive impairment and Alzheimer's/INS; disease or other forms of dementia

Background: Aerobic training has been shown to promote structural and functional neurocognitive plasticity in cognitively intact older adults. However, little is known about the neuroplastic potential of aerobic exercise in individuals at risk of Alzheimer’s disease (AD) and dementia. Objective: We aimed to explore the effect of aerobic exercise intervention and cardiorespiratory fitness improvement on brain and cognitive functions in older adults with amnestic mild cognitive impairment (aMCI). Methods: 27 participants with aMCI were randomized to either aerobic training (n = 13) or balance and toning (BAT) control group (n = 14) for a 16-week intervention. Pre- and post-assessments included functional MRI experiments of brain activation during associative memory encoding and neural synchronization during complex information processing, cognitive evaluation using neuropsychological tests, and cardiorespiratory fitness assessment. Results: The aerobic group demonstrated increased frontal activity during memory encoding and increased neural synchronization in higher-order cognitive regions such as the frontal cortex and temporo-parietal junction (TPJ) following the intervention. In contrast, the BAT control group demonstrated decreased brain activity during memory encoding, primarily in occipital, temporal, and parietal areas. Increases in cardiorespiratory fitness were associated with increases in brain activation in both the left inferior frontal and precentral gyri. Furthermore, changes in cardiorespiratory fitness were also correlated with changes in performance on several neuropsychological tests. Conclusion: Aerobic exercise training may result in functional plasticity of high-order cognitive areas, especially, frontal regions, among older adults at risk of AD and dementia. Furthermore, cardiorespiratory fitness may be an important mediating factor of the observed changes in neurocognitive functions.

Download Full-text

Distinct Subgroups of Amnestic Mild Cognitive Impairment as Identified by Soft Independent Modeling of Class Analogy

10.20944/preprints201905.0377.v1 ◽

2019 ◽

Author(s):

Sookjaroen Tangwongchai ◽

Itthipol Tawankanjanachot ◽

Chavit Tunvirachaisakul ◽

Thitiporn Supasitthumrong ◽

Solaphat Hemrungrojn ◽

...

Keyword(s):

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Neuropsychological Tests ◽

Diagnostic Category ◽

Principal Component ◽

Amnestic Mild Cognitive Impairment ◽

Cognitive Profile ◽

Support Vector ◽

Patients At Risk ◽

Normal Controls

Amnestic mild cognitive impairment (aMCI) is a condition characterized by mild deficits in episodic and semantic memory and learning. The conversion rate of aMCI to Alzheimer disease (AD) is significantly higher in aMCI than in the general population. The aim of this study is to examine whether aMCI is a valid diagnostic category or whether aMCI comprises different subgroups based on cognitive functions. We recruited 60 aMCI patients, 60 with AD and 61 healthy controls who completed neuropsychological tests of the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD-NP) and biomarkers including serum anion gap (AGAP). Principal component analysis, support vector machine and Soft Independent Modeling of Class Analogy (SIMCA) showed that AD patients and controls were highly significantly discrimanted from each other, while patients with aMCI overlap considerably with normal controls. SIMCA showed that 68.3% of the aMCI patients were assigned to the control class (named: aMCI-HC), 15% to AD (aMCI-AD), while 16.6% did not belong to either class (aMCI-strangers). aMCI-HC subjects showed sings of very mild cognitive decline and impaired recall. aMCI-strangers showed signs of mild cognitive impairment with impaired fluency and naming. aMCI-AD cases showed a cognitive profile reminiscent of AD an increased AGAP levels. In conclusion, our SIMCA model may classify subjects afforded a clinical diagnosis of aMCI according to Petersen’s criteria into three clinically relevant subgroups and help in the early detection of AD by identifying aMCI patients at risk to develop AD and those that have an AD prodrome.

Download Full-text

Addenbrooke's cognitive examination III: diagnostic utility for mild cognitive impairment and dementia and correlation with standardized neuropsychological tests

International Psychogeriatrics ◽

10.1017/s1041610216001496 ◽

2016 ◽

Vol 29 (1) ◽

pp. 105-113 ◽

Cited By ~ 27

Author(s):

Jordi A. Matias-Guiu ◽

Ana Cortés-Martínez ◽

Maria Valles-Salgado ◽

Teresa Rognoni ◽

Marta Fernández-Matarrubia ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Neuropsychological Tests ◽

Pearson Correlation ◽

Amnestic Mild Cognitive Impairment ◽

Visuospatial Function ◽

Early Stages ◽

Addenbrooke’S Cognitive Examination

ABSTRACTBackground:Addenbrooke's Cognitive Examination III (ACE-III) is a screening test that was recently validated for diagnosing dementia. Since it assesses attention, language, memory, fluency, and visuospatial function separately, it may also be useful for general neuropsychological assessments. The aim of this study was to analyze the tool's ability to detect early stages of Alzheimer's disease and to examine the correlation between ACE-III scores and scores on standardized neuropsychological tests.Methods:Our study included 200 participants categorized as follows: 25 healthy controls, 48 individuals with subjective memory complaints, 47 patients with amnestic mild cognitive impairment and 47 mild Alzheimer's disease, and 33 patients with other neurodegenerative diseases.Results:The ACE-III memory and language domains were highly correlated with the neuropsychological tests specific to those domains (Pearson correlation coefficient of 0.806 for total delayed recall on the Free and Cued Selective Reminding Test vs. 0.744 on the Boston Naming Test). ACE-III scores discriminated between controls and patients with amnestic mild cognitive impairment (AUC: 0.906), and between controls and patients with mild Alzheimer's disease (AUC: 0.978).Conclusion:Our results suggest that ACE-III is a useful neuropsychological test for assessing the cognitive domains of attention, language, memory, and visuospatial function. It also enables detection of Alzheimer's disease in early stages.

Download Full-text