Association Between Ginkgo Biloba Extract Prescriptions and Dementia Incidence in Outpatients with Mild Cognitive Impairment in Germany: A Retrospective Cohort Study
Authors: Bohlken, Jens | Peters, Oliver | Kostev, Karel
Article Type: Research Article
Abstract: Background: Clinical trials have demonstrated a significant effectiveness of Ginkgo biloba therapy versus placebo in patients with dementia. Objective: The present study aims to analyze the impact of Ginkgo biloba drug prescriptions on dementia incidence in patients with mild cognitive impairment (MCI) in a real-world setting. Methods: This retrospective study was based on the IQVIA Disease Analyzer database and included patients aged 65 or older with a first diagnosis of MCI from January 2000 to December 2019. Each patient was followed for up to 20 years after MCI diagnosis until February 2021. Date of the first diagnosis of dementia or …loss to follow-up, whichever occurred first, was noted. To estimate the association between Ginkgo biloba prescriptions during the follow-up and dementia incidence, a multivariable Cox regression analysis was performed, adjusted for age, sex, health insurance, documented co-diagnoses, and prescription of cholinesterase inhibitors. Results: Overall, 24,483 MCI patients (mean age: 77.0 years, 56.3% women) were included. It was found that > 2 prescriptions of Ginkgo biloba were significantly associated with a reduced dementia incidence (HR: 0.71 (95% CI: 0.55–0.91), p = 0.007), as compared with no Ginkgo biloba prescription. The effect of receiving > 3 Ginkgo biloba prescriptions was even stronger, with an HR of 0.64 (95% CI: 0.48–0.86), p = 0.003), while for > 4 prescriptions the HR was 0.58 (95% CI: 0.41–0.82) (p = 0.002). Conclusion: All-cause dementia incidence decreased with higher numbers of Ginkgo biloba prescriptions in MCI patients. Show more
Keywords: Dementia, Ginkgo biloba extract, mild cognitive impairment, outpatients
DOI: 10.3233/JAD-215348
Citation: Journal of Alzheimer's Disease, vol. 86, no. 2, pp. 703-709, 2022
Plasma Amyloid Concentration in Alzheimer’s Disease: Performance of a High-Throughput Amyloid Assay in Distinguishing Alzheimer’s Disease Cases from Controls
Authors: Feinkohl, Insa | Schipke, Carola G. | Kruppa, Jochen | Menne, Felix | Winterer, Georg | Pischon, Tobias | Peters, Oliver
Article Type: Research Article
Abstract: Background: Collection of cerebrospinal fluid (CSF) for measurement of amyloid-β (Aβ) species is a gold standard in Alzheimer’s disease (AD) diagnosis, but has risks. Thus, establishing a low-risk blood Aβ test with high AD sensitivity and specificity is of outmost interest. Objective: We evaluated the ability of a commercially available plasma Aβ assay to distinguish AD patients from biomarker-healthy controls. Method: In a case-control design, we examined plasma samples from 44 AD patients (A + N+) and 49 controls (A–N–) from a memory clinic. AD was diagnosed using a combination of neuropsychological examination, CSF biomarker analysis and brain imaging. Total Aβ40 and …total Aβ42 in plasma were measured through enzyme-linked immunosorbent assay (ELISA) technology using ABtest40 and ABtest42 test kits (Araclon Biotech Ltd.). Receiver operating characteristic (ROC) analyses with outcome AD were performed, and sensitivity and specificity were calculated. Results: Plasma Aβ42/40 was weakly positively correlated with CSF Aβ42/40 (Spearman’s rho 0.22; p = 0.037). Plasma Aβ42/40 alone was not able to statistically significantly distinguish between AD patients and controls (AUC 0.58; 95% CI 0.46, 0.70). At a cut-point of 0.076 maximizing sensitivity and specificity, plasma Aβ42/40 had a sensitivity of 61.2% and a specificity of 63.6%. Conclusion: In this sample, the high-throughput blood Aβ assay was not able to distinguish well between AD patients and controls. Whether or not the assay may be useful in large-scale epidemiological settings remains to be seen. Show more
Keywords: Alzheimer’s disease, amyloid, diagnosis, high-throughput assay, plasma
DOI: 10.3233/JAD-200046
Citation: Journal of Alzheimer's Disease, vol. 74, no. 4, pp. 1285-1294, 2020
Individualized Summary Assessment of Detailed Neuropsychological Testing for the Etiological Diagnosis of Newly Detected Cognitive Impairment in Hospitalized Geriatric Patients
Authors: Mäurer, Anja | Himmel, Gudrun | Lange, Catharina | Mathies, Franziska | Apostolova, Ivayla | Peters, Oliver | Buchert, Ralph
Article Type: Research Article
Abstract: Background: Neuropsychological testing (NPT) of geriatric inpatients can be affected by the acute illness and/or the hospitalization. Objective: To test individualized interpretation of detailed NPT for the differentiation between primary ‘neurodegenerative’ etiologies (predominantly Alzheimer’s disease) and ‘other’ etiologies (including cerebrovascular disease) of newly detected cognitive impairment in geriatric inpatients without and with delirium in remission. Methods: 96 geriatric inpatients (81.9±5.6 years, 64.6% females) with clinically uncertain cognitive impairment were included. 31.3% had delirium in remission that was not considered the primary cause of the cognitive impairment. Categorization of the most likely etiology as ‘neurodegenerative’ or ‘other’ was established retrospectively by …a study neuropsychologist based on individualized summary assessment of detailed NPT compiled in a standardized vignette. The etiological diagnosis based on FDG-PET served as gold standard (54.2% ‘neurodegenerative’, 45.8% ‘other’). Results: Individualized summary assessment by the study neuropsychologist was correct in 80 patients (83.3%, 8 false positive, 8 false negative). The impact of delirium in remission was not significant (p = 0.237). Individualized summary assessment by an independent neuropsychologist resulted in more false positive cases (n = 22) at the same rate of false negative cases (n = 8). Automatic categorization with a decision tree model based on the most discriminative NPT scores was correct in 68 patients (70.8%, 14 false positive, 14 false negative). Conclusion: Individualized summary assessment of detailed NPT in the context of relevant clinical information might be useful for the etiological diagnosis of newly detected cognitive impairment in hospitalized geriatric patients, also in patients with delirium in remission, but requires task-specific expertise. Show more
Keywords: Alzheimer’s disease, delirium, dementia, etiological diagnosis, hospitalized geriatric patients, neuropsychological testing
DOI: 10.3233/JAD-221273
Citation: Journal of Alzheimer's Disease, vol. 94, no. 2, pp. 559-584, 2023
Value of Neuropsychological Tests to Identify Patients with Depressive Symptoms on the Alzheimer’s Disease Continuum
Authors: Menne, Felix | Schipke, Carola Gertrud | Klostermann, Arne | Fuentes-Casañ, Manuel | Freiesleben, Silka Dawn | Bauer, Chris | Peters, Oliver
Article Type: Research Article
Abstract: Background: Depressive symptoms often co-occur with Alzheimer’s disease (AD) and can impact neuropsychological test results. In early stages of AD, disentangling cognitive impairments due to depression from those due to neurodegeneration often poses a challenge. Objective: We aimed to identify neuropsychological tests able to detect AD-typical pathology while taking into account varying degrees of depressive symptoms. Methods: A battery of neuropsychological tests (CERAD-NP) and the Geriatric Depression Scale (GDS) were assessed, and cerebrospinal fluid (CSF) biomarkers were obtained. After stratifying patients into CSF positive or negative and into low, moderate, or high GDS score groups, sensitivity and specificity and area …under the curve (AUC) were calculated for each subtest. Results: 497 participants were included in the analyses. In patients with low GDS scores (≤10), the highest AUC (0.72) was achieved by Mini-Mental State Examination, followed by Constructional Praxis Recall and Wordlist Total Recall (AUC = 0.714, both). In patients with moderate (11–20) and high (≥21) GDS scores, Trail Making Test-B (TMT-B) revealed the highest AUCs with 0.77 and 0.82, respectively. Conclusion: Neuropsychological tests showing AD-typical pathology in participants with low GDS scores are in-line with previous results. In patients with higher GDS scores, TMT-B showed the best discrimination. This indicates the need to focus on executive function rather than on memory task results in depressed patients to explore a risk for AD. Show more
Keywords: Alzheimer’s disease, cerebrospinal fluid, depression, executive function, memory, neuropsychology
DOI: 10.3233/JAD-200710
Citation: Journal of Alzheimer's Disease, vol. 78, no. 2, pp. 819-826, 2020
Validation of the Erlangen Score Algorithm for the Prediction of the Development of Dementia due to Alzheimer’s Disease in Pre-Dementia Subjects
Authors: Lewczuk, Piotr | Kornhuber, Johannes | Toledo, Jon B. | Trojanowski, John Q. | Knapik-Czajka, Malgorzata | Peters, Oliver | Wiltfang, Jens | Shaw, Leslie M.
Article Type: Correction
DOI: 10.3233/JAD-159006
Citation: Journal of Alzheimer's Disease, vol. 49, no. 3, pp. 887-887, 2016
Cerebrospinal Fluid Biomarkers and Clinical Progression in Patients with Subjective Cognitive Decline and Mild Cognitive Impairment
Authors: Wolfsgruber, Steffen | Polcher, Alexandra | Koppara, Alexander | Kleineidam, Luca | Frölich, Lutz | Peters, Oliver | Hüll, Michael | Rüther, Eckart | Wiltfang, Jens | Maier, Wolfgang | Kornhuber, Johannes | Lewczuk, Piotr | Jessen, Frank | Wagner, Michael
Article Type: Research Article
Abstract: Background: There is very limited data on the prevalence of abnormal cerebrospinal fluid (CSF) biomarkers of Alzheimer’s disease (AD) and their predictive value for clinical progression in memory clinic patients with subjective cognitive decline (SCD). Objective: To assess the frequency of abnormal CSF biomarkers of AD and their predictive value for clinical progression in memory clinic patients with SCD in comparison to patients with mild cognitive impairment (MCI) from the same cohort. Methods: We analyzed prospective data from memory clinic patients of the German Competence Network Dementia cohort with a baseline diagnosis of SCD (n = 82) or MCI (n = 134), …distinguished by actuarial neuropsychological MCI criteria (“Jak-Bondi criteria”). Risk of clinical progression during 3-year follow-up was evaluated with Cox-Proportional-Hazard models. Results: Prevalence of abnormal values in CSF markers of tau-mediated neurodegeneration (67.8% versus 46.3%) but not of amyloid deposition (40.3% versus 35.4%) was significantly higher in MCI compared to SCD. The rate of incident AD dementia (26.1% versus 12.2%) was also significantly higher in MCI. In SCD, additional 22% progressed to MCI during follow-up. Combined amyloid/tau abnormality was the strongest predictor of clinical progression in both groups. Conclusion: High prevalence of biomarker abnormality and clinical progression, together with the predictive value of CSF biomarkers, in memory clinic patients with SCD support the validity and usefulness of this condition as a “pre-MCI” at risk stage of AD. Show more
Keywords: Alzheimer’s disease, cerebrospinal fluid, mild cognitive impairment, subjective cognitive decline
DOI: 10.3233/JAD-161252
Citation: Journal of Alzheimer's Disease, vol. 58, no. 3, pp. 939-950, 2017
Long-Term Stability of Alzheimer's Disease Biomarker Proteins in Cerebrospinal Fluid
Authors: Schipke, Carola G. | Jessen, Frank | Teipel, Stefan | Luckhaus, Christian | Wiltfang, Jens | Esselmann, Hermann | Frölich, Lutz | Maier, Wolfgang | Rüther, Eckart | Heppner, Frank L. | Prokop, Stefan | Heuser, Isabella | Peters, Oliver
Article Type: Research Article
Abstract: The quantitative analysis of peptides in human cerebrospinal fluid (CSF) has become an important step in the early diagnosis of dementia, e.g., Alzheimer's disease. In search of new biomarkers for early detection and differential diagnosis of chronic neurodegenerative diseases, “biobanking” and long-term storage of human samples is increasingly important. The German Dementia Competence Network (DCN) has accomplished one of the largest biomaterial banks in this field, comprising CSF from several hundreds of patients. Since little is known about long-term stability of biomarker proteins in frozen CSF, we investigated the reliability of quantitative analysis in a total of 56 CSF samples …that had been frozen for up to six years. Here, we compare a second quantitative analysis of Aβ40 , Aβ42 , and the total-tau protein after several years of storage at −80°C with initial results obtained within six months after lumbar puncture. The second analysis was done using standard ELISAs or the newly developed Mesocale System. We found that regarding Aβ42 and total-tau, the results highly correlate with correlation coefficients of c = 0.73 and c = 0.82 respectively, while for Aβ40 the correlation coefficient was lower (c = 0.53), suggesting that Aβ40 is more vulnerable to degradation. We conclude that the quantitative analysis of the concentration of Aβ42 , as well as for total-tau, in CSF in samples that have been stored for years is reliable. The determination of these biomarkers and potentially new biomarkers in CSF samples stored in large biomaterial banks assembled over many years is feasible. Show more
Keywords: Alzheimer's disease, amyloid-β protein, biomarkers, cerebrospinal fluid, protein stability, tau-protein
DOI: 10.3233/JAD-2011-110329
Citation: Journal of Alzheimer's Disease, vol. 26, no. 2, pp. 255-262, 2011
Astrocyte Function is Modified by Alzheimer's Disease-like Pathology in Aged Mice
Authors: Peters, Oliver | Schipke, Carola G. | Philipps, Andreas | Haas, Brigitte | Pannasch, Ulrike | Wang, Li Ping | Benedetti, Bruno | Kingston, Ann E. | Kettenmann, Helmut
Article Type: Research Article
Abstract: Alzheimer's disease (AD) may affect all cell types in the central nervous system. Astrocytes have rarely been investigated in the aged brain and the role of astrocytes in AD is poorly understood. In this study, we used acute brain slices from an amyloid-β overexpressing double transgenic mouse line where astrocytes express the enhanced green fluorescent protein under the control of the glial fibrillary acidic protein promoter. Using the patch-clamp technique, we analyzed cell coupling and glutamate reactivity, two main features of astrocytes, in the living tissue of aged mice in an AD mouse model. We found large astrocytic networks in …the aged (20 to 27 months) transgenic animals in the neocortex, but not in the hippocampus. In contrast, coupling was low in all brain regions of aged control mice. We furthermore noticed significant changes in the responses of astrocytes to glutamate. The expression of functional glutamate transporters and AMPA/kainate-type glutamate receptors increases in the amyloid-β protein precursor overexpressing mice. Thus, exposure to amyloid-β leads to altered astrocyte properties and this change might be beneficial to maintain synaptic function. Show more
Keywords: Alzheimer's disease, astrocyte, coupling, gap junction, glia, glutamate receptor, glutamate transporter, neurodegeneration
DOI: 10.3233/JAD-2009-1140
Citation: Journal of Alzheimer's Disease, vol. 18, no. 1, pp. 177-189, 2009
Prediction of Alzheimer’s Dementia in Patients with Amnestic Mild Cognitive Impairment in Clinical Routine: Incremental Value of Biomarkers of Neurodegeneration and Brain Amyloidosis Added Stepwise to…
Authors: Lange, Catharina | Suppa, Per | Pietrzyk, Uwe | Makowski, Marcus R. | Spies, Lothar | Peters, Oliver | Buchert, Ralph | for the Alzheimer’s Disease Neuroimaging Initiative
Article Type: Research Article
Abstract: The aim of this study was to evaluate the incremental benefit of biomarkers for prediction of Alzheimer’s disease dementia (ADD) in patients with mild cognitive impairment (MCI) when added stepwise in the order of their collection in clinical routine. The model started with cognitive status characterized by the ADAS-13 score. Hippocampus volume (HV), cerebrospinal fluid (CSF) phospho-tau (pTau), and the FDG t-sum score in an AD meta-region-of-interest were compared as neurodegeneration markers. CSF-Aβ1-42 was used as amyloidosis marker. The incremental prognostic benefit from these markers was assessed by stepwise Kaplan-Meier survival analysis in 402 ADNI MCI subjects. Predefined cutoffs were …used to dichotomize patients as ‘negative’ or ‘positive’ for AD characteristic alteration with respect to each marker. Among the neurodegeneration markers, CSF-pTau provided the best incremental risk stratification when added to ADAS-13. FDG PET outperformed HV only in MCI subjects with relatively preserved cognition. Adding CSF-Aβ provided further risk stratification in pTau-positive subjects, independent of their cognitive status. Stepwise integration of biomarkers allows stepwise refinement of risk estimates for MCI-to-ADD progression. Incremental benefit strongly depends on the patient’s status according to the preceding diagnostic steps. The stepwise Kaplan-Meier curves might be useful to optimize diagnostic workflow in individual patients. Show more
Keywords: Alzheimer’s disease, biomarker, cerebrospinal fluid, FDG, magnetic resonance imaging, mild cognitive impairment, neuropsychological testing, positron emission tomography, prediction, white matter hyperintensities
DOI: 10.3233/JAD-170705
Citation: Journal of Alzheimer's Disease, vol. 61, no. 1, pp. 373-388, 2018
A Comparison of Operational Definitions for Mild Cognitive Impairment
Authors: Polcher, Alexandra | Wolfsgruber, Steffen | Peters, Oliver | Frölich, Lutz | Wiltfang, Jens | Kornhuber, Johannes | Hüll, Michael | Rüther, Eckart | Lewczuk, Piotr | Maier, Wolfgang | Jessen, Frank | Wagner, Michael
Article Type: Research Article
Abstract: Background: Consideration of many tests from different cognitive domains in defining mild cognitive impairment (MCI) is clinical routine, but guidelines for a neuropsychological operationalization of MCI are lacking. Objective: Among different operational MCI criteria, to identify those which are best in predicting either conversion to dementia, or a biomarker profile indicative for Alzheimer’s disease (AD). Methods: Memory clinic patients without dementia (N = 558; mean age = 66; up to 3 years of follow-up; n = 360 with baseline CSF biomarkers) were included in an observational study using most liberal criteria of cognitive impairment. Four operational definitions of MCI were retrospectively applied: 1) amnestic …MCI (CERAD word list delayed recall), 2) CERAD total score, 3) comprehensive criteria and 4) base rate corrected CERAD. We compared their accuracy in predicting incident all-cause dementia or AD dementia within three years, or a concurrent CSF Aβ42 /tau-ratio indicative of AD. Results: The four definitions overlapped considerably, classified 35–58% of the original sample as impaired and were associated with markedly increased PPVs regarding incident all-cause dementia (39–46% versus 26% of the original sample), AD dementia and AD biomarker positivity. The base rate corrected MCI definition had the highest prognostic accuracy. Conclusion: he operational criteria examined seem suitable to specify MCI in memory clinic settings, as they identify subjects at high risk of clinical progression. Depending on the neuropsychological battery in use, one or several of these criteria could help to calibrate the clinical judgment of test results, reduce false-positive decisions, and define risk-enriched groups for clinical trials. Show more
Keywords: Alzheimer’s disease, biomarker, cognition, conversion, dementia, diagnosis, DSM-5 mild NCD, mild cognitive impairment, prognosis
DOI: 10.3233/JAD-215548
Citation: Journal of Alzheimer's Disease, vol. 88, no. 4, pp. 1663-1678, 2022