scholarly journals Serum Daytime Melatonin Levels Reflect Cerebrospinal Fluid Melatonin Levels in Alzheimer’s Disease but Are Not Correlated with Cognitive Decline

2021 ◽  
pp. 1-12
Author(s):  
Amber Nous ◽  
Mandy Melissa Jane Wittens ◽  
Yannick Vermeiren ◽  
Peter Paul De Deyn ◽  
Christine Van Broeckhoven ◽  
...  

Background: Nocturnal cerebrospinal fluid (CSF) and blood melatonin levels are altered in Alzheimer’s disease (AD). However, literature remains inconclusive on daytime blood melatonin levels. A positive correlation between melatonin levels and Mini-Mental State Examination (MMSE) scores in AD subjects has been evidenced following cross-sectional analyses. Whereas a correlation between serum and spinal CSF melatonin has been shown in healthy volunteers, an equal investigation in AD patients still has to be undertaken. Objective: 1) To evaluate whether serum melatonin levels correlate with spinal CSF melatonin levels in AD. 2) To compare daytime CSF and serum melatonin levels between patients with AD dementia, mild cognitive impairment due to AD, and healthy controls, and to evaluate whether melatonin can affect cognitive decline in AD. Methods: Subjects with AD and healthy controls included in two existing cohorts, of whom a CSF and serum sample was available at the neurobiobank and had at least 6 months of neuropsychological follow-up, were included in the present study. Melatonin concentrations were measured with liquid chromatography-mass spectrometry. Results: Daytime serum melatonin levels correlated with spinal CSF melatonin levels in AD (r = 0.751, p <  0.001). No significant differences regarding daytime melatonin levels were found between patients and controls. No correlations were observed between daytime melatonin levels and MMSE score changes. Conclusion: Daytime serum melatonin accurately reflects CSF melatonin levels in AD, raising the possibility to assess melatonin alterations by solely performing blood sampling if also confirmed for night-time values. However, daytime melatonin levels are not associated with changes of cognitive impairment.

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.


2019 ◽  
Author(s):  
Rewadee Jenraumjit ◽  
Surarong Chinwong ◽  
Dujrudee Chinwong ◽  
Tipaporn Kanjanarach ◽  
Thanat Kshetradat ◽  
...  

Abstract Objective Age-associated decline in central cholinergic activity makes older adults susceptible to harmful effects of anticholinergics (ACs). Evidence exists of an association between effects of AC medications on cognition. This retrospective cohort study examines how ACs affect cognition among older adults with Alzheimer’s disease (AD) who received acetylcholine esterase inhibitors (AChEIs) over the course of 12 months. Results A total of 133 (80% women, mean age 78.38 years, SD 7.4) were recruited. No difference in sex, age and comorbid diseases was observed between participants who took ACs, Benzodiazepines (BZDs) and AChEIs. The most common prescribed ACs was quetiapine, being used for behavioral and psychological symptoms (BPSD). Multilevel analysis showed that the change of mental state examination scores were significantly predicted in the group using ACs (t (169), -2.52, p = .020) but not with the groups using BZD (t (162), 0.84, p = .440). Evidence showed that older adults with Alzheimer’s disease and exposed to ACs exhibited lower global cognitive scores than those without AC exposure. Using ACs could be a trade-off between controlling BPSD and aggravating cognitive impairment. Highlighting the awareness of the potential anticholinergic effect is important and may be the best policy.


2020 ◽  
pp. 1-13
Author(s):  
Karolina Minta ◽  
Gunnar Brinkmalm ◽  
Erik Portelius ◽  
Per Johansson ◽  
Johan Svensson ◽  
...  

Background: Brevican and neurocan are central nervous system-specific extracellular matrix proteoglycans. They are degraded by extracellular enzymes, such as metalloproteinases. However, their degradation profile is largely unexplored in cerebrospinal fluid (CSF). Objective: The study aim was to quantify proteolytic peptides derived from brevican and neurocan in human CSF of patients with Alzheimer’s disease (AD) and vascular dementia (VaD) compared with controls. Methods: The first cohort consisted of 75 individuals including 25 patients with AD, 7 with mild cognitive impairment (MCI) diagnosed with AD upon follow-up, 10 patients with VaD or MCI diagnosed with VaD upon follow-up, and 33 healthy controls and cognitively stable MCI patients. In the second cohort, 31 individuals were included (5 AD patients, 14 VaD patients and 12 healthy controls). Twenty proteolytic peptides derived from brevican (n = 9) and neurocan (n = 11) were quantified using high-resolution parallel reaction monitoring mass spectrometry. Results: In the first cohort, the majority of CSF concentrations of brevican and neurocan peptides were significantly decreased inVaDas compared withADpatients (AUC = 0.83.0.93, p≤0.05) and as compared with the control group (AUC = 0.79.0.87, p ≤ 0.05). In the second cohort, CSF concentrations of two brevican peptides (B87, B156) were significantly decreased in VaD compared with AD (AUC = 0.86.0.91, p ≤ 0.05) and to controls (AUC = 0.80.0.82, p ≤ 0.05), while other brevican and neurocan peptides showed a clear trend to be decreased in VaD compared with AD (AUC = 0.64.80, p > 0.05). No peptides differed between AD and controls. Conclusion: Brevican and neurocan peptides are potential diagnostic biomarkers for VaD, with ability to separate VaD from AD.


2020 ◽  
Vol 77 (2) ◽  
pp. 843-853
Author(s):  
Antoine R. Trammell ◽  
Darius J. McDaniel ◽  
Malik Obideen ◽  
Maureen Okafor ◽  
Tiffany L. Thomas ◽  
...  

Background: African Americans (AA) have a higher Alzheimer’s disease (AD) prevalence and report more perceived stress than White Americans. The biological basis of the stress-AD link is unclear. This study investigates the connection between stress and AD biomarkers in a biracial cohort. Objective: Establish biomarker evidence for the observed association between stress and AD, especially in AA. Methods: A cross-sectional study (n = 364, 41.8% AA) administering cognitive tests and the perceived stress scale (PSS) questionnaire. A subset (n = 309) provided cerebrospinal fluid for measurement of Aβ42, Tau, Ptau, Tau/Aβ42 (TAR), and Ptau/Aβ42 (PTAR). Multivariate linear regression, including factors that confound racial differences in AD, was performed. Results: Higher PSS scores were associated with higher Ptau (β= 0.43, p = 0.01) and PTAR (β= 0.005, p = 0.03) in AA with impaired cognition (mild cognitive impairment). Conclusion: Higher PSS scores were associated with Tau-related AD biomarker indices in AA/MCI, suggesting a potential biological connection for stress with AD and its racial disparity.


2020 ◽  
Vol 77 (3) ◽  
pp. 1143-1155
Author(s):  
Daniela Enache ◽  
Joana B. Pereira ◽  
Vesna Jelic ◽  
Bengt Winblad ◽  
Per Nilsson ◽  
...  

Background: Cognitive deficits arising in the course of Alzheimer’s disease (AD), dementia with Lewy bodies (DLB), and Parkinson’s disease with dementia (PDD) are directly linked to synaptic loss. Postmortem studies suggest that zinc transporter protein 3 (ZnT3), AMPA glutamate receptor 3 (GluA3), and Dynamin1 are associated with cognitive decline in AD and Lewy body dementia patients. Objective: We aimed to evaluate the diagnostic value of ZnT3, GluA3, and Dynamin 1 in the cerebrospinal fluid (CSF) of patients with dementia due to AD, DLB, and PDD compared to cognitively normal subjective cognitive decline (SCD) patients in a retrospective study. In addition, we assessed the relationship between synaptic markers and age, sex, cognitive impairment, and depressive symptoms as well as CSF amyloid, phosphorylated tau (p-tau), and total tau (T-tau). Methods: Commercially available ELISA immunoassay was used to measure the levels of proteins in a total of 97 CSF samples from AD (N = 24), PDD (N = 18), DLB (N = 27), and SCD (N = 28) patients. Cognitive impairment was assessed using the Mini-Mental State Examination (MMSE). Results: We found a significant increase in the concentrations of ZnT3, GluA3, and Dynamin1 in AD (p = 0.002) and of ZnT3 and Dynamin 1 in DLB (p = 0.001, p = 0.002) when compared to SCD patients. Changes in ZnT3 concentrations correlated with MMSE scores in AD (p = 0.011), and with depressive symptoms in SCD (p = 0.041). Conclusion: We found alteration of CSF levels of synaptic proteins in AD, PDD, and DLB. Our results reveal distinct changes in CSF concentrations of ZnT3 that could reflect cognitive impairment in AD with implications for future prognostic and diagnostic marker development.


2017 ◽  
Vol 30 (1) ◽  
pp. 103-113 ◽  
Author(s):  
N. Siafarikas ◽  
G. Selbaek ◽  
T. Fladby ◽  
J. Šaltytė Benth ◽  
E. Auning ◽  
...  

ABSTRACTBackground:Neuropsychiatric symptoms (NPS), such as depression, apathy, agitation, and psychotic symptoms are common in mild cognitive impairment (MCI) and dementia in Alzheimer's disease (AD). Subgroups of NPS have been reported. Yet the relationship of NPS and their subgroups to different stages of cognitive impairment is unclear. Most previous studies are based on small sample sizes and show conflicting results. We sought to examine the frequency of NPS and their subgroups in MCI and different stages of dementia in AD.Methods:This was a cross-sectional study using data from a Norwegian national registry of memory clinics. From a total sample of 4,571 patients, we included those with MCI or AD (MCI 817, mild AD 883, moderate–severe AD 441). To compare variables across groups ANOVA or χ2-test was applied. We used factor analysis of Neuropsychiatric Inventory Questionnaire (NPI-Q) items to identify subgroups of NPS.Results:The frequency of any NPS was 87.2% (AD 91.2%, MCI 79.5%; p < 0.001) and increased with increasing severity of cognitive decline. The most frequent NPS in MCI was depression. Apathy was the most frequent NPS in AD across different stages of severity. The factor analysis identified three subgroups in MCI and mild AD, and a fourth one in moderate–severe AD. We labelled the subgroups “depression,” “agitation,” “psychosis,” and “elation.”Conclusions:The frequency of NPS is high in MCI and AD and increases with the severity of cognitive decline. The subgroups of NPS were relatively consistent from MCI to moderate-severe AD. The subgroup elation appeared only in moderate-severe AD.


2020 ◽  
Author(s):  
Jiangbing Mao ◽  
Qinyong Ye ◽  
Hongqing Yang ◽  
Magda Bucholc ◽  
Shuo Liu ◽  
...  

Abstract Background:Machine learning (ML) techniques are expected to tackle the problem of the high prevalence of Alzheimer’s disease (AD) we are facing worldwide. However, few studies of novelty detection (ND), a typical ML technique for safety-critical systems especially in healthcare, were engaged for identifying the risk of developing cognitive impairment from healthy controls (HC) population.Materials and Methods: Two independent datasets were used for this study, including the Australian Imaging Biomarkers and Lifestyle Study of Ageing (AIBL) and the Fujian Medical University Union Hospital (FMUUH), China datasets. Multiple feature selection methods were applied to identify the most relevant features for predicting the severity of AD. Four easily interpretable ND algorithms, including k nearest neighbor, Mixture of Gaussian (MoG), KMEANS, and support vector data description were used to construct predictive models. The models were visualized by drawing their decision boundaries tightly surrounding the HC data. A distance to boundary (DtB) strategy was proposed to differentiate individuals with mild cognitive impairment (MCI) and AD from HC. Results: The best overall MCI&AD detection performance in both AIBL and FMUUH was obtained on the cognitive and functional assessments (CFA) modality only using MoG-based ND with AUC of 0.8757 and 0.9443, respectively. The highest sensitivity of MCI was presented by using a combination of CFA and brain imaging modality. The DTB value reflects the risk of developing cognitive impairment for HC and the dementia severity of MCI/AD.Conclusions: Our findings suggest that applying some non-invasive and cost-effective features can significantly detect cognitive decline in an early stage. The visualized decision boundary and the proposed DtB strategy illustrated the severity of cognitive decline of potential MCI&AD patients in an early stage. The results would help inform future guidelines for developing a clinical decision-making support system aiming at an early diagnosis and prognosis of MCI&AD.


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