Browsing by Author "Schofield, Peter"

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    Awareness of Genetic Risk in the Dominantly Inherited Alzheimer Network (DIAN)
    (Wiley, 2020-01) Aschenbrenner, Andrew J.; James, Bryan D.; McDade, Eric; Wang, Guoqiao; Lim, Yen Ying; Benzinger, Tammie L.S.; Cruchaga, Carlos; Goate, Alison; Xiong, Chengjie; Perrin, Richard; Buckles, Virginia; Allegri, Ricardo; Berman, Sarah B.; Chhatwal, Jasmeer P.; Fagan, Anne; Farlow, Martin; O'Connor, Antoinette; Ghetti, Bernardino; Graff-Radford, Neill; Goldman, Jill; Gräber, Susanne; Karch, Celeste M.; Lee, Jae-Hong; Levin, Johannes; Martins, Ralph N.; Masters, Colin; Mori, Hiroshi; Noble, James; Salloway, Stephen; Schofield, Peter; Morris, John C.; Bateman, Randall J.; Hassenstab, Jason; Neurology, School of Medicine
    Introduction: Although some members of families with autosomal dominant Alzheimer's disease mutations learn their mutation status, most do not. How knowledge of mutation status affects clinical disease progression is unknown. This study quantifies the influence of mutation awareness on clinical symptoms, cognition, and biomarkers. Methods: Mutation carriers and non-carriers from the Dominantly Inherited Alzheimer Network (DIAN) were stratified based on knowledge of mutation status. Rates of change on standard clinical, cognitive, and neuroimaging outcomes were examined. Results: Mutation knowledge had no associations with cognitive decline, clinical progression, amyloid deposition, hippocampal volume, or depression in either carriers or non-carriers. Carriers who learned their status mid-study had slightly higher levels of depression and lower cognitive scores. Discussion: Knowledge of mutation status does not affect rates of change on any measured outcome. Learning of status mid-study may confer short-term changes in cognitive functioning, or changes in cognition may influence the determination of mutation status.
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    Effect of BDNFVal66Met on disease markers in dominantly inherited Alzheimer's disease
    (Wiley, 2018-09) Lim, Yen Ying; Hassenstab, Jason; Goate, Alison; Fagan, Anne M.; Benzinger, Tammie L.S.; Cruchaga, Carlos; McDade, Eric; Chhatwal, Jasmeer; Levin, Johannes; Farlow, Martin R.; GraffRadford, Neill R.; Laske, Christoph; Masters, Colin L; Salloway, Stephen; Schofield, Peter; Morris, John C.; Maruff, Paul; Bateman, Randall J.; Neurology, School of Medicine
    OBJECTIVE: Previous studies suggest that the brain-derived neurotrophic factor (BDNF) Val66Met (rs6265) polymorphism may influence symptom onset in Alzheimer's disease (AD). Our recent cross-sectional findings suggest that Met66 may influence clinical expression in dominantly inherited AD (DIAD) through its effects on tau. However, it remains unclear whether carriage of Met66 in DIAD results in faster increases in cerebrospinal fluid (CSF) tau and ptau181 , and whether these increases are associated with accelerated brain volume loss and memory decline. METHODS: A total of 211 subjects (101 mutation noncarriers, 110 mutation carriers), who were cognitively normal, as defined by a Clinical Dementia Rating global score of 0, completed assessments of cognitive function, neuroimaging, and CSF sampling over 3.5 years as part of the Dominantly Inherited Alzheimer's Network. RESULTS: In mutation carriers, Met66 carriers showed faster memory decline (4×), hippocampal volume loss (16×), and CSF tau and ptau181 increases (6×) than Val66 homozygotes. BDNF did not influence rates of cortical β-amyloid accumulation or change in CSF Aβ42 levels in mutation carriers. In mutation noncarriers, BDNF genotype had no effect on change in cognition, brain volume, cortical β-amyloid accumulation, or change in any CSF measures of tau, ptau181 , and CSF Aβ42 . INTERPRETATION: As in sporadic AD, the deleterious effects of β-amyloid on cognitive function, brain volume loss, and CSF tau in DIAD mutation carriers are less in Val66 homozygotes. The BDNF Val66Met polymorphism should be considered as a potential moderator of clinical trial outcomes in current treatment and prevention trials in DIAD and sporadic AD. Ann Neurol 2018;84:424-435.
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    Metabolomic and lipidomic signatures in autosomal dominant and late-onset Alzheimer's disease brains
    (Wiley, 2023) Novotny, Brenna C.; Fernandez, Maria Victoria; Wang, Ciyang; Budde, John P.; Bergmann, Kristy; Eteleeb, Abdallah M.; Bradley, Joseph; Webster, Carol; Ebl, Curtis; Norton, Joanne; Gentsch, Jen; Dube, Umber; Wang, Fengxian; Morris, John C.; Bateman, Randall J.; Perrin, Richard J.; McDade, Eric; Xiong, Chengjie; Chhatwal, Jasmeer; Dominantly Inherited Alzheimer Network (DIAN) Study Group; Alzheimer's Disease Neuroimaging Initiative; Alzheimer's Disease Metabolomics Consortium (ADMC); Goate, Alison; Farlow, Martin; Schofield, Peter; Chui, Helena; Karch, Celeste M.; Cruchaga, Carlos; Benitez, Bruno A.; Harari, Oscar; Neurology, School of Medicine
    Introduction: The identification of multiple genetic risk factors for Alzheimer's disease (AD) suggests that many pathways contribute to AD onset and progression. However, the metabolomic and lipidomic profiles in carriers of distinct genetic risk factors are not fully understood. The metabolome can provide a direct image of dysregulated pathways in the brain. Methods: We interrogated metabolomic signatures in the AD brain, including carriers of pathogenic variants in APP, PSEN1, and PSEN2 (autosomal dominant AD; ADAD), APOE ɛ4, and TREM2 risk variant carriers, and sporadic AD (sAD). Results: We identified 133 unique and shared metabolites associated with ADAD, TREM2, and sAD. We identified a signature of 16 metabolites significantly altered between groups and associated with AD duration. Discussion: AD genetic variants show distinct metabolic perturbations. Investigation of these metabolites may provide greater insight into the etiology of AD and its impact on clinical presentation. Highlights: APP/PSEN1/PSEN2 and TREM2 variant carriers show distinct metabolic changes. A total of 133 metabolites were differentially abundant in AD genetic groups. β-citrylglutamate is differentially abundant in autosomal dominant, TREM2, and sporadic AD. A 16-metabolite profile shows differences between Alzheimer's disease (AD) genetic groups. The identified metabolic profile is associated with duration of disease.
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    Segregation of functional networks is associated with cognitive resilience in Alzheimer's disease
    (Oxford University Press, 2021) Ewers, Michael; Luan, Ying; Frontzkowski, Lukas; Neitzel, Julia; Rubinski, Anna; Dichgans, Martin; Hassenstab, Jason; Gordon, Brian A.; Chhatwal, Jasmeer P.; Levin, Johannes; Schofield, Peter; Benzinger, Tammie L.S; Morris, John C.; Goate, Alison; Karch, Celeste M.; Fagan, Anne M.; McDade, Eric; Allegri, Ricardo; Berman, Sarah; Chui, Helena; Cruchaga, Carlos; Farlow, Marty; Graff-Radford, Neill; Jucker, Mathias; Lee, Jae-Hong; Martins, Ralph N.; Mori, Hiroshi; Perrin, Richard; Xiong, Chengjie; Rossor, Martin; Fox, Nick C.; O’Connor, Antoinette; Salloway, Stephen; Danek, Adrian; Buerger, Katharina; Bateman, Randall J.; Habeck, Christian; Stern, Yaakov; Franzmeier, Nicolai; Alzheimer’s Disease Neuroimaging Initiative; Dominantly Inherited Alzheimer Network; Neurology, School of Medicine
    Cognitive resilience is an important modulating factor of cognitive decline in Alzheimer's disease, but the functional brain mechanisms that support cognitive resilience remain elusive. Given previous findings in normal ageing, we tested the hypothesis that higher segregation of the brain's connectome into distinct functional networks represents a functional mechanism underlying cognitive resilience in Alzheimer's disease. Using resting-state functional MRI, we assessed both resting-state functional MRI global system segregation, i.e. the balance of between-network to within-network connectivity, and the alternate index of modularity Q as predictors of cognitive resilience. We performed all analyses in two independent samples for validation: (i) 108 individuals with autosomal dominantly inherited Alzheimer's disease and 71 non-carrier controls; and (ii) 156 amyloid-PET-positive subjects across the spectrum of sporadic Alzheimer's disease and 184 amyloid-negative controls. In the autosomal dominant Alzheimer's disease sample, disease severity was assessed by estimated years from symptom onset. In the sporadic Alzheimer's sample, disease stage was assessed by temporal lobe tau-PET (i.e. composite across Braak stage I and III regions). In both samples, we tested whether the effect of disease severity on cognition was attenuated at higher levels of functional network segregation. For autosomal dominant Alzheimer's disease, we found higher functional MRI-assessed system segregation to be associated with an attenuated effect of estimated years from symptom onset on global cognition (P = 0.007). Similarly, for patients with sporadic Alzheimer's disease, higher functional MRI-assessed system segregation was associated with less decrement in global cognition (P = 0.001) and episodic memory (P = 0.004) per unit increase of temporal lobe tau-PET. Confirmatory analyses using the alternate index of modularity Q revealed consistent results. In conclusion, higher segregation of functional connections into distinct large-scale networks supports cognitive resilience in Alzheimer's disease.
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    Serum neurofilament dynamics predicts neurodegeneration and clinical progression in presymptomatic Alzheimer's disease
    (Nature Research, 2019-02) Preische, Oliver; Schultz, Stephanie A.; Apel, Anja; Kuhle, Jens; Kaeser, Stephan A.; Barro, Christian; Gräber, Susanne; Kuder-Buletta, Elke; LaFougere, Christian; Laske, Christoph; Vöglein, Jonathan; Levin, Johannes; Masters, Colin L.; Martins, Ralph; Schofield, Peter R.; Rossor, Martin N.; Graff-Radford, Neill R.; Salloway, Stephen; Ghetti, Bernardino; Ringman, John M.; Noble, James M.; Chhatwal, Jasmeer; Goate, Alison M.; Benzinger, Tammie L. S.; Morris, John C.; Bateman, Randall J.; Wang, Guoqiao; Fagan, Anne M.; McDade, Eric M.; Gordon, Brian A.; Jucker, Mathias; Alzheimer Network; Allegri, Ricardo; Amtashar, Fatima; Bateman, Randall; Benzinger, Tammie; Berman, Sarah; Bodge, Courtney; Brandon, Susan; Brooks, William; Buck, Jill; Buckles, Virginia; Chea, Sochenda; Chhatwal, Jasmeer; Chrem, Patricio; Chui, Helena; Cinco, Jake; Clifford, Jack; Cruchaga, Carlos; D’Mello, Mirelle; Donahue, Tamara; Douglas, Jane; Edigo, Noelia; Erekin-Taner, Nilufer; Fagan, Anne; Farlow, Marty; Farrar, Angela; Feldman, Howard; Flynn, Gigi; Fox, Nick; Franklin, Erin; Fujii, Hisako; Gant, Cortaiga; Gardener, Samantha; Ghetti, Bernardino; Goate, Alison; Goldman, Jill; Gordon, Brian; Graff-Radford, Neill; Gray, Julia; Gurney, Jenny; Hassenstab, Jason; Hirohara, Mie; Holtzman, David; Hornbeck, Russ; DiBari, Siri Houeland; Ikeuchi, Takeshi; Ikonomovic, Snezana; Jerome, Gina; Jucker, Mathias; Karch, Celeste; Kasuga, Kensaku; Kawarabayashi, Takeshi; Klunk, William; Koeppe, Robert; Kuder-Buletta, Elke; Laske, Christoph; Lee, Jae-Hong; Levin, Johannes; Marcus, Daniel; Martins, Ralph; Mason, Neal Scott; Masters, Colin; Maue-Dreyfus, Denise; McDade, Eric; Montoya, Lucy; Mori, Hiroshi; Morris, John; Nagamatsu, Akem; Neimeyer, Katie; Noble, James; Norton, Joanne; Perrin, Richard; Raichle, Marc; Ringman, John; Roh, Jee Hoon; Salloway, Stephen; Schofield, Peter; Shimada, Hiroyuki; Shiroto, Tomoyo; Shoji, Mikio; Sigurdson, Wendy; Sohrabi, Hamid; Sparks, Paige; Suzuki, Kazushi; Swisher, Laura; Taddei, Kevin; Wang, Jen; Wang, Peter; Weiner, Mike; Wolfsberger, Mary; Xiong, Chengjie; Xu, Xiong; Pathology and Laboratory Medicine, School of Medicine
    Neurofilament light chain (NfL) is a promising fluid biomarker of disease progression for various cerebral proteopathies. Here we leverage the unique characteristics of the Dominantly Inherited Alzheimer Network and ultrasensitive immunoassay technology to demonstrate that NfL levels in the cerebrospinal fluid (n = 187) and serum (n = 405) are correlated with one another and are elevated at the presymptomatic stages of familial Alzheimer's disease. Longitudinal, within-person analysis of serum NfL dynamics (n = 196) confirmed this elevation and further revealed that the rate of change of serum NfL could discriminate mutation carriers from non-mutation carriers almost a decade earlier than cross-sectional absolute NfL levels (that is, 16.2 versus 6.8 years before the estimated symptom onset). Serum NfL rate of change peaked in participants converting from the presymptomatic to the symptomatic stage and was associated with cortical thinning assessed by magnetic resonance imaging, but less so with amyloid-β deposition or glucose metabolism (assessed by positron emission tomography). Serum NfL was predictive for both the rate of cortical thinning and cognitive changes assessed by the Mini-Mental State Examination and Logical Memory test. Thus, NfL dynamics in serum predict disease progression and brain neurodegeneration at the early presymptomatic stages of familial Alzheimer's disease, which supports its potential utility as a clinically useful biomarker.