| 1. |
- Voevodskaya, Olga, et al.
(author)
-
Myo-inositol changes precede amyloid pathology and relate to APOE genotype in Alzheimer disease
- 2016
-
In: Neurology. - : Lippincott Williams & Wilkins. - 0028-3878 .- 1526-632X. ; 86:19, s. 1754-1761
-
Journal article (peer-reviewed)abstract
- OBJECTIVE: We aimed to test whether in vivo levels of magnetic resonance spectroscopy (MRS) metabolites myo-inositol (mI), N-acetylaspartate (NAA), and choline are abnormal already during preclinical Alzheimer disease (AD), relating these changes to amyloid or tau pathology, and functional connectivity.METHODS: In this cross-sectional multicenter study (a subset of the prospective Swedish BioFINDER study), we included 4 groups, representing the different stages of predementia AD: (1) cognitively healthy elderly with normal CSF β-amyloid 42 (Aβ42), (2) cognitively healthy elderly with abnormal CSF Aβ42, (3) patients with subjective cognitive decline and abnormal CSF Aβ42, (4) patients with mild cognitive decline and abnormal CSF Aβ42 (Ntotal = 352). Spectroscopic markers measured in the posterior cingulate/precuneus were considered alongside known disease biomarkers: CSF Aβ42, phosphorylated tau, total tau, [(18)F]-flutemetamol PET, f-MRI, and the genetic risk factor APOE.RESULTS: Amyloid-positive cognitively healthy participants showed a significant increase in mI/creatine and mI/NAA levels compared to amyloid-negative healthy elderly (p < 0.05). In amyloid-positive healthy elderly, mI/creatine and mI/NAA correlated with cortical retention of [(18)F] flutemetamol tracer ([Formula: see text] = 0.44, p = 0.02 and [Formula: see text] = 0.51, p = 0.01, respectively). Healthy elderly APOE ε4 carriers with normal CSF Aβ42 levels had significantly higher mI/creatine levels (p < 0.001) than ε4 noncarriers. Finally, elevated mI/creatine was associated with decreased functional connectivity within the default mode network (rpearson = -0.16, p = 0.02), independently of amyloid pathology.CONCLUSIONS: mI levels are elevated already at asymptomatic stages of AD. Moreover, mI/creatine concentrations were increased in healthy APOE ε4 carriers with normal CSF Aβ42 levels, suggesting that mI levels may reveal regional brain consequences of APOE ε4 before detectable amyloid pathology.
|
|
| 2. |
- Damian, Marinella, et al.
(author)
-
Single-Domain Amnestic Mild Cognitive Impairment Identified by Cluster Analysis Predicts Alzheimer's Disease in the European Prospective DESCRIPA Study
- 2013
-
In: Dementia and Geriatric Cognitive Disorders. - : S. Karger AG. - 1420-8008 .- 1421-9824. ; 36:1-2, s. 1-19
-
Journal article (peer-reviewed)abstract
- Background/Aims: To identify prodromal Alzheimer's disease (AD) subjects using a data-driven approach to determine cognitive profiles in mild cognitive impairment (MCI). Methods: A total of 881 MCI subjects were recruited from 20 memory clinics and followed for up to 5 years. Outcome measures included cognitive variables, conversion to AD, and biomarkers (e. g. CSF, and MRI markers). Two hierarchical cluster analyses (HCA) were performed to identify clusters of subjects with distinct cognitive profiles. The first HCA included all subjects with complete cognitive data, whereas the second one selected subjects with very mild MCI (MMSE >= 28). ANOVAs and ANCOVAs were computed to examine whether the clusters differed with regard to conversion to AD, and to AD-specific biomarkers. Results: The HCAs identified 4-cluster solutions that best reflected the sample structure. One cluster (aMCIsingle) had a significantly higher conversion rate (19%), compared to subjective cognitive impairment (SCI, p < 0.0001), and non-amnestic MCI (naMCI, p = 0.012). This cluster was the only one showing a significantly different biomarker profile (A beta(42), t-tau, APOE epsilon 4, and medial temporal atrophy), compared to SCI or naMCI. Conclusion: In subjects with mild MCI, the single-domain amnestic MCI profile was associated with the highest risk of conversion, even if memory impairment did not necessarily cross specific cut-off points. A cognitive profile characterized by isolated memory deficits may be sufficient to warrant applying prevention strategies in MCI, whether or not memory performance lies below specific z-scores. This is supported by our preliminary biomarker analyses. However, further analyses with bigger samples are needed to corroborate these findings. Copyright (C) 2013 S. Karger AG, Basel
|
|
| 3. |
- Jacobs, Heidi I. L., et al.
(author)
-
The association between white matter hyperintensities and executive decline in mild cognitive impairment is network dependent
- 2012
-
In: Neurobiology of Aging. - : Elsevier BV. - 1558-1497 .- 0197-4580. ; 33:1, s. 1-201
-
Journal article (peer-reviewed)abstract
- White matter hyperintensities (WMH) in Mild Cognitive Impairment (MCI) have been associated with impaired executive functioning, although contradictory findings have been reported. The aim of this study was to examine whether WMH location influenced the relation between WMH and executive functioning in MCI participants (55-90 years) in the European multicenter memory-clinic-based DESCRIPA study, who underwent MRI scanning at baseline (N = 337). Linear mixed model analysis was performed to test the association between WMH damage in three networks (frontal-parietal, frontal-subcortical and frontal-parietal-subcortical network) and change in executive functioning over a 3-year period. WMH in the frontal-parietal and in the frontal-parietal-subcortical network were associated with decline in executive functioning. However, the frontal-subcortical network was not associated with change in executive functioning. Our results suggest that parietal WMH are a significant contributor to executive decline in MCI and that investigation of WMH in the cerebral networks supporting cognitive functions provide a new way to differentiate stable from cognitive declining MCI individuals. (C) 2012 Elsevier Inc. All rights reserved.
|
|
| 4. |
|
|
| 5. |
- Johansson, Annica, 1969, et al.
(author)
-
Genetic association of CDC2 with cerebrospinal fluid tau in Alzheimer's disease
- 2005
-
In: Dementia and Geriatric Cognitive Disorders. - : S. Karger AG. - 1420-8008 .- 1421-9824. ; 20:6, s. 367-374
-
Journal article (peer-reviewed)abstract
- We have recently reported that a polymorphism in the cell division cycle <i>(CDC2) </i>gene, designated Ex6 + 7I/D, is associated with Alzheimer’s disease (AD). The <i>CDC2</i> gene is located on chromosome 10q21.1 close to the marker D10S1225 linked to AD. Active cdc2 accumulates in neurons containing neurofibrillary tangles (NFT), a process that can precede the formation of NFT. Therefore, <i>CDC2 </i>is a promising candidate susceptibility gene for AD. We investigated the possible effects of the <i>CDC2</i> polymorphism on cerebrospinal fluid (CSF) biomarkers in AD patients. <i>CDC2</i> genotypes were evaluated in relation to CSF protein levels of total tau, phospho-tau and β-amyloid<sub>(1–42)</sub> in AD patients and control individuals, and in relation to the amount of senile plaques and NFT in the frontal cortex and in the hippocampus in patients with autopsy-proven AD and controls. The <i>CDC2</i> Ex6 + 7I allele was associated with a gene dose-dependent increase of CSF total tau levels (F<sub>2, 626</sub> = 7.0, p = 0.001) and the homozygous <i>CDC2</i> Ex6 + 7II genotype was significantly more frequent among AD patients compared to controls (p = 0.006, OR = 1.57, 95% CI 1.13–2.17). Our results provide further evidence for an involvement of cdc2 in the pathogenesis of AD.
|
|
| 6. |
- Leoni, Valerio, et al.
(author)
-
Diagnostic Power of 24S-Hydroxycholesterol in Cerebrospinal Fluid: Candidate Marker of Brain Health
- 2013
-
In: Journal of Alzheimer's Disease. - 1387-2877 .- 1875-8908. ; 36:4, s. 739-747
-
Journal article (peer-reviewed)abstract
- We evaluated the diagnostic potential of 24S-hydroxycholesterol (24OHC) in cerebrospinal fluid. At a memory clinic, we investigated subjects with subjective cognitive impairment (SCI, n = 33), mild cognitive impairment (MCI) patients (n = 27), MCI patients with later progression into Alzheimer dementia at follow up (n = 10), and patients with AD (n = 24). We also had a control group of healthy volunteers who did not later develop cognitive problems (n = 13). The fraction of the population with pathological levels of 24OHC was 8% in controls, 34% in SCI, 37% in MCI, 80% in MCI with progression, and 42% in AD. The corresponding fractions for T-tau, P-tau, and A beta(42) were lower in the case of SCI and MCI but higher in the case of controls and AD. In case of MCI with progression, the fraction of pathological levels of 24OHC and A beta(42) were 80% and 63% respectively. We also studied a population of old healthy subjects age 75-99 years (n = 25). The fraction of individuals in this population with pathological levels of 24OHC was 0% whereas the fraction of individuals with pathological level of at least one of the other three biomarkers was 40%. The diagnostic power of 24OHC in cerebrospinal fluid seems to be similar to or lower than that of the established biomarkers T-tau, P-tau, and A beta(42) in the diagnosis of established AD. Our data suggest that 24OHC may be more sensitive than the classical biomarkers in an early phase of the neurodegenerative process and a better marker for "brain health" in old age.
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
- van Rossum, Ineke A, et al.
(author)
-
Injury markers predict time to dementia in subjects with MCI and amyloid pathology.
- 2012
-
In: Neurology. - 1526-632X. ; 79:17, s. 1809-16
-
Journal article (peer-reviewed)abstract
- Alzheimer disease (AD) can now be diagnosed in subjects with mild cognitive impairment (MCI) using biomarkers. However, little is known about the rate of decline in those subjects. In this cohort study, we aimed to assess the conversion rate to dementia and identify prognostic markers in subjects with MCI and evidence of amyloid pathology.
|
|
| 10. |
- Vermeiren, Angelique P. A., et al.
(author)
-
The Association Between APOE epsilon 4 and Alzheimer-type Dementia Among Memory Clinic Patients is Confined to those with a Higher Education. The DESCRIPA Study
- 2013
-
In: Journal of Alzheimer's Disease. - 1387-2877 .- 1875-8908. ; 35:2, s. 241-246
-
Journal article (peer-reviewed)abstract
- We assessed the interaction between the APOE epsilon 4 allele and education level in the etiology of Alzheimer's disease (AD) among memory clinic patients from the multicenter DESCRIPA study. Subjects (n = 544) were followed for 1 to 5 years. We used Cox's stratified survival modeling, adjusted for age, gender, and center. APOE epsilon 4 predicted the onset of AD-type dementia in middle (HR 3.45 95% CI 1.79-6.65, n = 222) and high (HR 3.67 95% CI 1.36-9.89, n = 139) but not in low educated subjects (HR 0.81, 95% CI 0.38-1.72, n = 183). This suggests that mechanisms in developing Alzheimer-type dementia may differ between educational groups that raises questions related to Alzheimer-type dementia prevention.
|
|
