scholarly journals Subjective cognitive decline: The first clinical manifestation of Alzheimer's disease?

2016 ◽  
Vol 10 (3) ◽  
pp. 170-177 ◽  
Author(s):  
Adalberto Studart Neto ◽  
Ricardo Nitrini

ABSTRACT Background: Mild cognitive impairment is considered as the first clinical manifestation of Alzheimer's disease (AD), when the individual exhibits below performance on standardized neuropsychological tests. However, some subjects before having a lower performance on cognitive assessments already have a subjective memory complaint. Objective: A review about subjective cognitive decline, the association with AD biomarkers and risk of conversion to dementia. Methods: We performed a comprehensive non-systematic review on PubMed. The keywords used in the search were terms related to subjective cognitive decline. Results: Subjective cognitive decline is characterized by self-experience of deterioration in cognitive performance not detected objectively through formal neuropsychological testing. However, various terms and definitions have been used in the literature and the lack of a widely accepted concept hampers comparison of studies. Epidemiological data have shown that individuals with subjective cognitive decline are at increased risk of progression to AD dementia. In addition, there is evidence that this group has a higher prevalence of positive biomarkers for amyloidosis and neurodegeneration. However, Alzheimer's disease is not the only cause of subjective cognitive decline and various other conditions can be associated with subjective memory complaints, such as psychiatric disorders or normal aging. The features suggestive of a neurodegenerative disorder are: onset of decline within the last five years, age at onset above 60 years, associated concerns about decline and confirmation by an informant. Conclusion: These findings support the idea that subjective cognitive complaints may be an early clinical marker that precedes mild cognitive impairment due to Alzheimer's disease.

2021 ◽  
Vol 3 (3) ◽  
Author(s):  
Elizabeth Kuhn ◽  
Audrey Perrotin ◽  
Clémence Tomadesso ◽  
Claire André ◽  
Siya Sherif ◽  
...  

Abstract Subjective memory decline is associated with neurodegeneration and increased risk of cognitive decline in participants with no or subjective cognitive impairment, while in patients with mild cognitive impairment or Alzheimer’s-type dementia, findings are inconsistent. Our aim was to provide a comprehensive overview of subjective memory decline changes, relative to objective memory performances, and of their relationships with neurodegeneration, across the clinical continuum of Alzheimer’s disease. Two hundred participants from the Imagerie Multimodale de la maladie d'Alzheimer à un stade Précoce (IMAP+) primary cohort and 731 participants from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) replication cohort were included. They were divided into four clinical groups (Imagerie Multimodale de la maladie d'Alzheimer à un stade Précoce/Alzheimer’s Disease Neuroimaging Initiative): controls (n = 67/147, age: 60–84/60–90, female: 54/55%), patients with subjective cognitive decline (n = 30/84, age: 54–84/65–80, female: 44/63%), mild cognitive impairment (n = 50/369, age: 58–86/55–88, female: 45/44%) or Alzheimer’s-type dementia (n = 36/121, age: 51–86/61–90, female: 41/41%). Subjective and objective memory scores, and their difference (i.e. delta score reflecting memory awareness), were compared between groups. Then, voxelwise relationships between subjective memory decline and neuroimaging measures of neurodegeneration [atrophy (T1-MRI) and hypometabolism (18F-fluorodeoxyglucose-PET)] were assessed across clinical groups and the interactive effect of the level of cognitive impairment within the entire sample was assessed. Analyses were adjusted for age, sex and education, and repeated including only the amyloid-positive participants. In Imagerie Multimodale de la maladie d'Alzheimer à un stade Précoce, the level of subjective memory decline was higher in all patient groups (all P < 0.001) relative to controls, but similar between patient groups. In contrast, objective memory deficits progressively worsened from the subjective cognitive decline to the dementia group (all P < 0.001). Accordingly, the delta score showed a progressive decline in memory awareness across clinical groups (all P < 0.001). Voxelwise analyses revealed opposite relationships between the subjective memory decline score and neurodegeneration across the clinical continuum. In the earliest stages (i.e. patients with subjective cognitive decline or Mini Mental State Examination > 28), greater subjective memory decline was associated with increased neurodegeneration, while in later stages (i.e. patients with mild cognitive impairment, dementia or Mini Mental State Examination < 27) a lower score was related to more neurodegeneration. Similar findings were recovered in the Alzheimer’s Disease Neuroimaging Initiative replication cohort, with slight differences according to the clinical group, and in the amyloid-positive subsamples. Altogether, our findings suggest that the subjective memory decline score should be interpreted differently from normal cognition to dementia. Higher scores might reflect greater neurodegeneration in earliest stages, while in more advanced stages lower scores might reflect decreased memory awareness, i.e. more anosognosia associated with advanced neurodegeneration.


2018 ◽  
Vol 15 (3) ◽  
pp. 219-228 ◽  
Author(s):  
Jiri Cerman ◽  
Ross Andel ◽  
Jan Laczo ◽  
Martin Vyhnalek ◽  
Zuzana Nedelska ◽  
...  

Background: Great effort has been put into developing simple and feasible tools capable to detect Alzheimer's disease (AD) in its early clinical stage. Spatial navigation impairment occurs very early in AD and is detectable even in the stage of mild cognitive impairment (MCI). Objective: The aim was to describe the frequency of self-reported spatial navigation complaints in patients with subjective cognitive decline (SCD), amnestic and non-amnestic MCI (aMCI, naMCI) and AD dementia and to assess whether a simple questionnaire based on these complaints may be used to detect early AD. Method: In total 184 subjects: patients with aMCI (n=61), naMCI (n=27), SCD (n=63), dementia due to AD (n=20) and normal controls (n=13) were recruited. The subjects underwent neuropsychological examination and were administered a questionnaire addressing spatial navigation complaints. Responses to the 15 items questionnaire were scaled into four categories (no, minor, moderate and major complaints). Results: 55% of patients with aMCI, 64% with naMCI, 68% with SCD and 72% with AD complained about their spatial navigation. 38-61% of these complaints were moderate or major. Only 33% normal controls expressed complaints and none was ranked as moderate or major. The SCD, aMCI and AD dementia patients were more likely to express complaints than normal controls (p's<0.050) after adjusting for age, education, sex, depressive symptoms (OR for SCD=4.00, aMCI=3.90, AD dementia=7.02) or anxiety (OR for SCD=3.59, aMCI=3.64, AD dementia=6.41). Conclusion: Spatial navigation complaints are a frequent symptom not only in AD, but also in SCD and aMCI and can potentially be detected by a simple and inexpensive questionnaire.


2021 ◽  
Author(s):  
Noel Valencia ◽  
Johann Lehrner

Summary Background Visuo-Constructive functions have considerable potential for the early diagnosis and monitoring of disease progression in Alzheimer’s disease. Objectives Using the Vienna Visuo-Constructional Test 3.0 (VVT 3.0), we measured visuo-constructive functions in subjective cognitive decline (SCD), mild cognitive impairment (MCI), Alzheimer’s disease (AD), and healthy controls to determine whether VVT performance can be used to distinguish these groups. Materials and methods Data of 671 participants was analyzed comparing scores across diagnostic groups and exploring associations with relevant clinical variables. Predictive validity was assessed using Receiver Operator Characteristic curves and multinomial logistic regression analysis. Results We found significant differences between AD and the other groups. Identification of cases suffering from visuo-constructive impairment was possible using VVT scores, but these did not permit classification into diagnostic subgroups. Conclusions In summary, VVT scores are useful indicators for visuo-constructive impairment but face challenges when attempting to discriminate between several diagnostic groups.


2017 ◽  
Vol 29 (6) ◽  
pp. 1105-1111 ◽  
Author(s):  
Mehmet Yuruyen ◽  
Fundan Engin Akcan ◽  
Gizem Cetiner Batun ◽  
Gozde Gultekin ◽  
Mesut Toprak ◽  
...  

2021 ◽  
Vol 19 ◽  
Author(s):  
Fabrizia D’Antonio ◽  
Maria Ilenia De Bartolo ◽  
Gina Ferrazzano ◽  
Micaela Sepe Monti ◽  
Letizia Imbriano ◽  
...  

Background: Blink rate (BR) is considered a marker of dopaminergic activity in humans. BR is increased in patients with Mild Cognitive Impairment (MCI), but no study has yet investigated whether BR changes with the progression of cognitive decline from MCI to Alzheimer’s disease (AD) and whether BR abnormalities are present in subjects with Subjective Cognitive Decline (SCD). Objective: The aim of our study was to assess BR in patients with AD, MCI, and SCD and to correlate BR with demographic and clinical features of cognitive decline. Methods: We enrolled 22 subjects with SCD, 23 with MCI, and 18 with AD and a group of 20 age-matched healthy controls (HCs). Cognitive function was assessed by testing global cognitive status and frontal, attentional, memory, verbal, and visuospatial functions. BR was measured by counting the number of blinks per minute. Results: MCI subjects had an increased BR (p<0.001), whereas AD subjects had a lower BR than HCs (p<0.05). Conversely, SCD subjects had a BR similar to HCs. No significant correlations emerged between neuropsychological scores and BR in SCD, MCI, and AD subjects. Conclusion: Increased BR in MCI likely reflects early compensatory mechanisms occurring before AD, whereas decreased BR in AD suggests dopaminergic system involvement in this condition.


2019 ◽  
Vol 75 (7) ◽  
pp. 1382-1392 ◽  
Author(s):  
Marie Caillaud ◽  
Carol Hudon ◽  
Benjamin Boller ◽  
Simona Brambati ◽  
Simon Duchesne ◽  
...  

Abstract Objective The concepts of mild cognitive impairment (MCI) and subjective cognitive decline (SCD) have been proposed to identify individuals in the early stages of Alzheimer’s disease (AD), or other neurodegenerative diseases. One approach to validate these concepts is to investigate the relationship between pathological brain markers and cognition in those individuals. Method We included 126 participants from the Consortium for the Early Identification of Alzheimer’s disease-Quebec (CIMA-Q) cohort (67 SCD, 29 MCI, and 30 cognitively healthy controls [CH]). All participants underwent a complete cognitive assessment and structural magnetic resonance imaging. Group comparisons were done using cognitive data, and then correlated with hippocampal volumes and white matter hyperintensities (WMHs). Results Significant differences were found between participants with MCI and CH on episodic and executive tasks, but no differences were found when comparing SCD and CH. Scores on episodic memory tests correlated with hippocampal volumes in both MCI and SCD, whereas performance on executive tests correlated with WMH in all of our groups. Discussion As expected, the SCD group was shown to be cognitively healthy on tasks where MCI participants showed impairment. However, SCD’s hippocampal volume related to episodic memory performances, and WMH to executive functions. Thus, SCD represents a valid research concept and should be used, alongside MCI, to better understand the preclinical/prodromal phase of AD.


Sign in / Sign up

Export Citation Format

Share Document