| 1. |
- Emersic, Andreja, et al.
(författare)
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Cerebrospinal fluid p-tau181, 217, and 231 in definite Creutzfeldt-Jakob disease with and without concomitant pathologies
- 2024
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Ingår i: ALZHEIMERS & DEMENTIA. - 1552-5260 .- 1552-5279.
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTIONThe established cerebrospinal fluid (CSF) phosphorylated tau181 (p-tau181) may not reliably reflect concomitant Alzheimer's disease (AD) and primary age-related tauopathy (PART) found in Creutzfeldt-Jakob disease (CJD) at autopsy. METHODSWe investigated CSF N-terminal p-tau181, p-tau217, and p-tau231 with in-house Simoa assays in definite CJD (n = 29), AD dementia (n = 75), mild cognitive impairment (MCI) due to AD (n = 65), and subjective cognitive decline (SCD, n = 28). Post-mortem examination performed in patients with CJD 1.3 (0.3-14.3) months after CSF collection revealed no co-pathology in 10, concomitant AD in 8, PART in 8, and other co-pathologies in 3 patients. RESULTSN-terminal p-tau was increased in CJD versus SCD (p < 0.0001) and correlated with total tau (t-tau) in the presence of AD and PART co-pathology (rho = 0.758-0.952, p <= 001). Concentrations in CJD(+AD )were indistinguishable from AD dementia, with the largest fold-change in p-tau217 (11.6), followed by p-tau231 and p-tau181 (3.2-4.5). DISCUSSIONVariable fold-changes and correlation with t-tau suggest that p-tau closely associates with neurodegeneration and concomitant AD in CJD. Highlights N-terminal phosphorylated tau (p-tau) biomarkers are increased in Creutzfeldt-Jakob disease (CJD) with and without concomitant AD. P-tau217, p-tau231, and p-tau181 correlate with total tau (t-tau) and increase in the presence of amyloid beta (A beta) co-pathology. N-terminal p-tau181 and p-tau231 in A beta-negative CJD show variation among PRNP genotypes. Compared to mid-region-targeting p-tau181, cerebrospinal fluid (CSF) N-terminal p-tau has greater potential to reflect post-mortem neuropathology in the CJD brain.
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| 2. |
- Enache, Daniela, et al.
(författare)
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CAIDE Dementia Risk Score and biomarkers of neurodegeneration in memory clinic patients without dementia
- 2016
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Ingår i: Neurobiology of Aging. - : Elsevier BV. - 0197-4580 .- 1558-1497. ; 42, s. 124-131
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to explore cross-sectional associations between Cardiovascular Risk Factors, Aging and Dementia Study (CAIDE) Dementia Risk Score and dementia-related cerebrospinal fluid and neuroimaging biomarkers in 724 patients without dementia from the Memory Clinic at Karolinska University Hospital, Huddinge, Sweden. We additionally evaluated the score's capacity to predict dementia. Two risk score versions were calculated: one including age, gender, obesity, hyperlipidemia, and hypertension; and one additionally including apolipoprotein E (APOE) ε4 carrier status. Cerebrospinal fluid was analyzed for amyloid β (Aβ), total tau, and phosphorylated tau. Visual assessments of medial temporal lobe atrophy (MTA), global cortical atrophy-frontal subscale, and Fazekas scale for white matter changes (WMC) were performed. Higher CAIDE Dementia Risk Score (version without APOE) was significantly associated with higher total tau, more severe MTA, WMC, and global cortical atrophy-frontal subscale. Higher CAIDE Dementia Risk Score (version with APOE) was associated with reduced Aβ, more severe MTA, and WMC. CAIDE Dementia Risk Score version with APOE seemed to predict dementia better in this memory clinic population with short follow-up than the version without APOE.
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| 3. |
- Garcia-Ptacek, Sara, et al.
(författare)
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Subjective cognitive impairment subjects in our clinical practice
- 2014
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Ingår i: Dementia and Geriatric Cognitive Disorders Extra. - : S. Karger AG. - 1664-5464. ; 4:3, s. 419-430
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:The clinical challenge in subjective cognitive impairment (SCI) is to identify which individuals will present cognitive decline. We created a statistical model to determine which variables contribute to SCI and mild cognitive impairment (MCI) versus Alzheimer's disease (AD) diagnoses.METHODS:A total of 993 subjects diagnosed at a memory clinic (2007-2009) were included retrospectively: 433 with SCI, 373 with MCI and 187 with AD. Descriptive statistics were provided. A logistic regression model analyzed the likelihood of SCI and MCI patients being diagnosed with AD, using age, gender, Mini-Mental State Examination score, the ratio of β-amyloid 42 divided by total tau, and phosphorylated tau as independent variables.RESULTS:The SCI subjects were younger (57.8 ± 8 years) than the MCI (64.2 ± 10.6 years) and AD subjects (70.1 ± 9.7 years). They were more educated, had less medial temporal lobe atrophy (MTA) and frequently normal cerebrospinal fluid biomarkers. Apolipoprotein E4/E4 homozygotes and apolipoprotein E3/E4 heterozygotes were significantly less frequent in the SCI group (6 and 36%) than in the AD group (28 and 51%). Within the regression model, cardiovascular risk factors, confluent white matter lesions, MTA and central atrophy increased the AD likelihood for SCI subjects.CONCLUSIONS:SCI patients form a distinct group. In our model, factors suggesting cardiovascular risk, MTA and central atrophy increased the AD likelihood for SCI subjects.
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| 4. |
- Kac, Przemyslaw R., et al.
(författare)
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Plasma p-tau212: antemortem diagnostic performance and prediction of autopsy verification of Alzheimer's disease neuropathology.
- 2023
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Ingår i: medRxiv : the preprint server for health sciences.
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Blood phosphorylated tau (p-tau) biomarkers, including p-tau217, show high associations with Alzheimer's disease (AD) neuropathologic change and clinical stage. Certain plasma p-tau217 assays recognize tau forms phosphorylated additionally at threonine-212, but the contribution of p-tau212 alone to AD is unknown. We developed a blood-based immunoassay that is specific to p-tau212 without cross-reactivity to p-tau217. Thereafter, we examined the diagnostic utility of plasma p-tau212. In five cohorts (n=388 participants), plasma p-tau212 showed high performances for AD diagnosis and for the detection of both amyloid and tau pathology, including at autopsy as well as in memory clinic populations. The diagnostic accuracy and fold changes of plasma p-tau212 were similar to those for p-tau217 but higher than p-tau181 and p-tau231. Immunofluorescent staining of brain tissue slices showed prominent p-tau212 reactivity in neurofibrillary tangles that co-localized with p-tau217 and p-tau202/205. These findings support plasma p-tau212 as a novel peripherally accessible biomarker of AD pathophysiology.
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| 5. |
- Kac, Przemyslaw R., 1995, et al.
(författare)
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Plasma p-tau212 antemortem diagnostic performance and prediction of autopsy verification of Alzheimer's disease neuropathology.
- 2024
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Ingår i: Nature communications. - 2041-1723. ; 15:1
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Tidskriftsartikel (refereegranskat)abstract
- Blood phosphorylated tau (p-tau) biomarkers, including p-tau217, show high associations with Alzheimer's disease (AD) neuropathologic change and clinical stage. Certain plasma p-tau217 assays recognize tau forms phosphorylated additionally at threonine-212, but the contribution of p-tau212 alone to AD is unknown. We developed a blood-based immunoassay that is specific to p-tau212 without cross-reactivity to p-tau217. Here, we examined the diagnostic utility of plasma p-tau212. In five cohorts (n=388 participants), plasma p-tau212 showed high performances for AD diagnosis and for the detection of both amyloid and tau pathology, including at autopsy as well as in memory clinic populations. The diagnostic accuracy and fold changes of plasma p-tau212 were similar to those for p-tau217 but higher than p-tau181 and p-tau231. Immunofluorescent staining of brain tissue slices showed prominent p-tau212 reactivity in neurofibrillary tangles that co-localized with p-tau217 and p-tau202/205. These findings support plasma p-tau212 as a peripherally accessible biomarker of AD pathophysiology.
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| 6. |
- Karikari, Thomas, et al.
(författare)
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Head-to-head comparison of clinical performance of CSF phospho-tau T181 and T217 biomarkers for Alzheimer's disease diagnosis.
- 2021
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Ingår i: Alzheimer's & dementia : the journal of the Alzheimer's Association. - : Wiley. - 1552-5279. ; 17:5, s. 755-767
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Tidskriftsartikel (refereegranskat)abstract
- Phosphorylated tau (p-tau) in cerebrospinal fluid (CSF) is an established Alzheimer's disease (AD) biomarker. Novel immunoassays targeting N-terminal and mid-region p-tau181 and p-tau217 fragments are available, but head-to-head comparison in clinical settings is lacking.N-terminal-directed p-tau217 (N-p-tau217), N-terminal-directed p-tau181 (N-p-tau181), and standard mid-region p-tau181 (Mid-p-tau181) biomarkers in CSF were evaluated in three cohorts (n=503) to assess diagnostic performance, concordance, and associations with amyloid beta (Aβ).CSF N-p-tau217 and N-p-tau181 had better concordance (88.2%) than either with Mid-p-tau181 (79.7%-82.7%). N-p-tau217 and N-p-tau181 were significantly increased in early mild cognitive impairment (MCI)-AD (A+T-N-) without changes in Mid-p-tau181 until AD-dementia. N-p-tau217 and N-p-tau181 identified Aβ pathophysiology (area under the curve [AUC]=94.8%-97.1%) and distinguished MCI-AD from non-AD MCI (AUC=82.6%-90.5%) signficantly better than Mid-p-tau181 (AUC=91.2% and 70.6%, respectively). P-tau biomarkers equally differentiated AD from non-AD dementia (AUC=99.1%-99.8%).N-p-tau217 and N-p-tau181 could improve diagnostic accuracy in prodromal-AD and clinical trial recruitment as both identify Aβ pathophysiology and differentiate early MCI-AD better than Mid-p-tau181.
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| 7. |
- Kramberger, Milica Gregoric, et al.
(författare)
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Association between EEG abnormalities and CSF biomarkers in a memory clinic cohort
- 2013
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Ingår i: Dementia and Geriatric Cognitive Disorders. - : S. Karger. - 1420-8008 .- 1421-9824. ; 36:5-6, s. 319-328
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Tidskriftsartikel (refereegranskat)abstract
- Background: The aim of the study was to describe distinct electroencephalogram (EEG) phenotypes defined after routine visual EEG analysis in a large memory clinic cohort and to investigate their relationship to cerebrospinal fluid (CSF) biomarkers. Methods: Patients with Alzheimer's disease (n = 131), mild cognitive impairment (n = 285), subjective cognitive impairment (n = 310), and mixed dementia (n = 29) were assessed clinically with neuroimaging, EEG and CSF investigations. EEG phenotypes were based on frequency of background activity (BA) and presence and degree of episodic abnormalities (EA). Results: BA and EA differed significantly (p < 0.001) between diagnostic groups. A lower CSF amyloid β42/phospho-tau ratio and higher total tau were associated with slower BA (p < 0.01) and a higher degree of EA (p < 0.04). Conclusions: Slowing of BA in combination with EA seems to be related to biological markers of neurodegeneration
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| 8. |
- Kramberger, Milica Gregoric, et al.
(författare)
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Cerebrospinal fluid alzheimer markers in depressed elderly dubjects with and without alzheimer's disease
- 2012
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Ingår i: Dementia and Geriatric Cognitive Disorders Extra. - : S. Karger AG. - 1664-5464. ; 2:1, s. 48-56
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Tidskriftsartikel (refereegranskat)abstract
- Background: The aim of this study was to explore the relationship between cerebrospinal fluid Alzheimer's disease (AD) markers and depression in elderly people.Method: We included subjects with AD as well as persons with subjective cognitive impairment and normal cognition. Depression was assessed with the Cornell Scale for Depression in Dementia, and a cut-off score of >6 was used to define depression. Cerebrospinal fluid was analyzed using commercially available assays for β-amyloid 1-42, total tau, and phosphorylated tau 181.Result: A total of 183 participants (66.7% female) were included (92 with AD and 91 with subjective cognitive impairment), with a mean age (±SD) of 67.6 ± 7.4 years, a Mini-Mental State Examination score of 26.0 ± 4.0, and a median Cornell Scale for Depression in Dementia score of 5 (range 0-19). Depression scores were not associated with higher phosphorylated tau 181 and total tau or reduced β-amyloid 1-42 in AD or non-demented subjects.Conclusions: These results suggest that AD pathology does not contribute to depression, indicating that other factors may be more important. Further studies of the aetiology of depression in elderly people with and without AD are warranted.
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| 9. |
- Smailovic, Una, et al.
(författare)
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Quantitative EEG power and synchronization correlate with Alzheimer's disease CSF biomarkers
- 2018
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Ingår i: Neurobiology of Aging. - : Elsevier BV. - 0197-4580 .- 1558-1497. ; 63, s. 88-95
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Tidskriftsartikel (refereegranskat)abstract
- Synaptic dysfunction is the best anatomical correlate of early cognitive impairment in Alzheimer's disease (AD). Electroencephalography (EEG) directly reflects brain electrical activity at the level of synapses. The aim of the present study was to investigate correlations of quantitative EEG measures, global field power (GFP) and global field synchronization (GFS), with conventional cerebrospinal fluid (CSF) biomarkers of neurodegeneration in patients diagnosed with subjective cognitive decline (n = 210), mild cognitive impairment (n = 230), and AD (n = 197). Decreased CSF amyloid beta 42 significantly correlated with increased theta and delta GFP, whereas increased p- and t-tau with decreased alpha and beta GFP. Decreased CSF amyloid beta 42 and increased p- and t-tau were significantly associated with decreased GFS alpha and beta. Subanalysis of the separate diagnostic groups demonstrated significant correlations between CSF biomarkers and generalized power and synchronization already in the subjective cognitive decline and mild cognitive impairment group. These results provide evidence that quantitative EEG measures are associated and possibly sensitive to distinct AD-like CSF biomarker profiles in cognitively impaired patients and are therefore promising early noninvasive markers of AD.
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| 10. |
- Snellman, Anniina, et al.
(författare)
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N-terminal and mid-region tau fragments as fluid biomarkers in neurological diseases.
- 2022
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Ingår i: Brain : a journal of neurology. - : Oxford University Press (OUP). - 1460-2156. ; 145:8, s. 2834-2848
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Tidskriftsartikel (refereegranskat)abstract
- Brain-derived tau secreted into CSF and blood consists of different N-terminal and mid-domain fragments, which may have a differential temporal course and thus, biomarker potential across the Alzheimer's disease continuum or in other neurological diseases. While current clinically validated total-tau (t-tau) assays target mid-domain epitopes, comparison of these assays with new biomarkers targeting N-terminal epitopes using the same analytical platform may be important to increase the understanding of tau pathophysiology. We developed three t-tau immunoassays targeting specific N-terminal (NTA and NTB t-tau) or mid-region (MR t-tau) epitopes, using single molecule array technology. After analytical validation, the diagnostic performance of these biomarkers was evaluated in CSF and compared with the Innotest t-tau (and as proof of concept, with N-p-tau181 and N-p-tau217) in three clinical cohorts (n = 342 total). The cohorts included participants across the Alzheimer's disease continuum (n = 276), other dementia (n = 22), Creutzfeldt-Jakob disease (n = 24), acute neurological disorders (n = 18) and progressive supranuclear palsy (n = 22). Furthermore, we evaluated all three new t-tau biomarkers in plasma (n = 44) and replicated promising findings with NTA t-tau in another clinical cohort (n = 50). In CSF, all t-tau biomarkers were increased in Alzheimer's disease compared with controls (P < 0.0001) and correlated with each other (rs = 0.53-0.95). NTA and NTB t-tau, but not other t-tau assays, distinguished amyloid-positive and amyloid-negative mild cognitive impairment with high accuracies (AUCs 84% and 82%, P < 0.001) matching N-p-tau217 (AUC 83%; DeLong test P = 0.93 and 0.88). All t-tau assays were excellent in differentiating Alzheimer's disease from other dementias (P < 0.001, AUCs 89-100%). In Creutzfeldt-Jakob disease and acute neurological disorders, N-terminal t-tau biomarkers had significantly higher fold changes versus controls in CSF (45-133-fold increase) than Innotest or MR t-tau (11-42-fold increase, P < 0.0001 for all). In progressive supranuclear palsy, CSF concentrations of all t-tau biomarkers were similar to those in controls. Plasma NTA t-tau concentrations were increased in Alzheimer's disease compared with controls in two independent cohorts (P = 0.0056 and 0.0033) while Quanterix t-tau performed poorly (P = 0.55 and 0.44). Taken together, N-terminal-directed CSF t-tau biomarkers increase ahead of standard t-tau alternatives in the Alzheimer's disease continuum, increase to higher degrees in Creutzfeldt-Jakob disease and acute neurological diseases and show better potential than Quanterix t-tau as Alzheimer's disease blood biomarkers. For progressive supranuclear palsy, other tau biomarkers should still be investigated.
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