Browsing by Author "Young, Christina B."
Now showing 1 - 4 of 4
Results Per Page
Sort Options
Item Amyloid PET predicts longitudinal functional and cognitive trajectories in a heterogeneous cohort(Wiley, 2025) Younes, Kyan; Johns, Emily; Young, Christina B.; Kennedy, Gabriel; Mukherjee, Shubhabrata; Vossler, Hillary A.; Winer, Joseph; Cody, Karly; Henderson, Victor W.; Poston, Kathleen L.; Betthauser, Tobey J.; Bevis, Bill; Brooks, William M.; Burns, Jeffrey M.; Coombes, Stephen A.; DeCarli, Charles; DiFilippo, Frank P.; Duara, Ranjan; Fan, Audrey P.; Gibbons, Laura E.; Golde, Todd; Johnson, Sterling C.; Lepping, Rebecca J.; Leverenz, James; McDougall, Sean; Rogalski, Emily; Sanders, Elizabeth; Pasaye, Joshua; Sridhar, Jaiashre; Saykin, Andrew J.; Sridharan, Anjali; Swerdlow, Russell; Trittschuh, Emily H.; Vaillancourt, David; Vidoni, Eric; Wang, Wei-En; Mez, Jesse; Hohman, Timothy J.; Tosun, Duygu; Biber, Sarah; Kukull, Walter A.; Crane, Paul K.; Mormino, Elizabeth C.; Radiology and Imaging Sciences, School of MedicineIntroduction: Amyloid positron emission tomography (PET) is increasingly available for diagnosis of Alzheimer`s disease (AD); however, its practical implications in heterogenous cohorts are debated. Methods: Amyloid PET from 890 National Alzheimer`s Coordinating Center participants with up to 10 years post-PET follow up was analyzed. Cox proportional hazards and linear mixed models were used to investigate amyloid burden prediction of etiology and prospective functional status and cognitive decline. Results: Amyloid positivity was associated with progression from unimpaired to mild cognitive impairment and dementia. Amyloid burden in the unimpaired group was associated with lower initial memory levels and faster decline in memory, language, and global cognition. In the Impaired group, amyloid was associated with lower initial levels and faster decline for memory, language, executive function, and global cognition. Discussion: Amyloid burden is an important prognostic marker in a clinically heterogeneous cohort. Future work is needed to establish the proportion of decline driven by AD versus non-AD processes in the context of mixed pathology. Highlights: Our findings highlight the importance of amyloid positron emission tomography (PET) in heterogenous cohorts, including diverse demographics, clinical syndromes, and underlying etiologies. The results also provide evidence that higher amyloid levels were linked to functional progression from unimpaired cognition to mild cognitive impairment (MCI) and from MCI to dementia. In cognitively unimpaired individuals, higher amyloid burden was associated with poorer memory at baseline and subsequent declines in memory, language, and global cognition. Among individuals with cognitive impairment, amyloid burden was associated with worse initial memory, language, executive function, and global cognition, and faster declines over time.Item Divergent Cortical Tau Positron Emission Tomography Patterns Among Patients With Preclinical Alzheimer Disease(American Medical Association, 2022) Young, Christina B.; Winer, Joseph R.; Younes, Kyan; Cody, Karly A.; Betthauser, Tobey J.; Johnson, Sterling C.; Schultz, Aaron; Sperling, Reisa A.; Greicius, Michael D.; Cobos, Inma; Poston, Kathleen L.; Mormino, Elizabeth C.; Alzheimer’s Disease Neuroimaging Initiative; Harvard Aging Brain Study; Radiology and Imaging Sciences, School of MedicineImportance: Characterization of early tau deposition in individuals with preclinical Alzheimer disease (AD) is critical for prevention trials that aim to select individuals at risk for AD and halt the progression of disease. Objective: To evaluate the prevalence of cortical tau positron emission tomography (PET) heterogeneity in a large cohort of clinically unimpaired older adults with elevated β-amyloid (A+). Design, setting, and participants: This cross-sectional study examined prerandomized tau PET, amyloid PET, structural magnetic resonance imaging, demographic, and cognitive data from the Anti-Amyloid Treatment in Asymptomatic AD (A4) Study from April 2014 to December 2017. Follow-up analyses used observational tau PET data from the Alzheimer's Disease Neuroimaging Initiative (ADNI), the Harvard Aging Brain Study (HABS), and the Wisconsin Registry for Alzheimer's Prevention and the Wisconsin Alzheimer's Disease Research Center (together hereinafter referred to as Wisconsin) to evaluate consistency. Participants were clinically unimpaired at the study visit closest to the tau PET scan and had available amyloid and tau PET data (A4 Study, n = 447; ADNI, n = 433; HABS, n = 190; and Wisconsin, n = 328). No participants who met eligibility criteria were excluded. Data were analyzed from May 11, 2021, to January 25, 2022. Main outcomes and measures: Individuals with preclinical AD with heterogeneous cortical tau PET patterns (A+T cortical+) were identified by examining asymmetrical cortical tau signal and disproportionate cortical tau signal relative to medial temporal lobe (MTL) tau. Voxelwise tau patterns, amyloid, neurodegeneration, cognition, and demographic characteristics were examined. Results: The 447 A4 participants (A+ group, 392; and normal β-amyloid group, 55), with a mean (SD) age of 71.8 (4.8) years, included 239 women (54%). A total of 36 individuals in the A+ group (9% of the A+ group) exhibited heterogeneous cortical tau patterns and were further categorized into 3 subtypes: asymmetrical left, precuneus dominant, and asymmetrical right. A total of 116 individuals in the A+ group (30% of the A+ group) showed elevated MTL tau (A+T MTL+). Individuals in the A+T cortical+ group were younger than those in the A+T MTL+ group (t61.867 = -2.597; P = .03). Across the A+T cortical+ and A+T MTL+ groups, increased regional tau was associated with reduced hippocampal volume and MTL thickness but not with cortical thickness. Memory scores were comparable between the A+T cortical+ and A+T MTL+ groups, whereas executive functioning scores were lower for the A+T cortical+ group than for the A+T MTL+ group. The prevalence of the A+T cortical+ group and tau patterns within the A+T cortical+ group were consistent in ADNI, HABS, and Wisconsin. Conclusions and relevance: This study suggests that early tau deposition may follow multiple trajectories during preclinical AD and may involve several cortical regions. Staging procedures, especially those based on neuropathology, that assume a uniform trajectory across individuals are insufficient for disease monitoring with tau imaging.Item Patterns of Tau Deposition by Cognitive Subtype in the Alzheimer's Disease Neuroimaging Initiative(Wiley, 2025-01-09) Scollard, Phoebe; Gibbons, Laura E.; Choi, Seo-Eun; Lee, Michael L.; Klinedinst, Brandon S.; Trittschuh, Emily H.; Mez, Jesse; Saykin, Andrew J.; Nakano, Connie; Sanders, Elizabeth; Lila, Eardi; Risacher, Shannon L.; Mormino, Elizabeth; Smith, Viktorija; Carlson, Mackenzie L.; Young, Christina B.; Crane, Paul K.; Mukherjee, Shubhabrata; Radiology and Imaging Sciences, School of MedicineBackground: Cognitive subtypes of Alzheimer’s Dementia (AD), defined by a relative impairment in a particular domain of cognition, have previously been shown to be associated with patterns of gray matter atrophy. Here we assessed the association of these subtypes with patterns of tau deposition measured in vivo using tau PET imaging in the Alzheimer’s Disease Neuroimaging Initiative (ADNI). Method: We included amyloid positive individuals with AD and Mild Cognitive Impairment (MCI). We selected the first diagnosis visit for AD and the most recent visit for MCI. Previously, AD individuals were categorized into AD‐Memory, AD‐Language, AD‐Executive, AD‐Visuospatial, AD‐Multiple domains, or AD‐No domain subtypes based on a relative cognitive impairment. These methods were extended to categorize MCI individuals. The AD/MCI‐Memory, AD/MCI‐Visuospatial, and AD/MCI‐No domain groups were large enough for our analyses. The tau PET scan closest to the subtyping visit was selected (median 49 days between scan and visit). Tau deposition for 35 brain regions (left and right sides averaged) were included as predictors. Separate five‐fold cross validated LASSO regressions were run for each of the three pairwise comparisons. Each model was repeated 100 times with different random fold selections to assess the stability of results. Result: We included 240 individuals (118 AD; 122 MCI) in our analyses (Table 1). There was some variation in the chosen models across repetitions with the AD/MCI‐Visuospatial versus AD/MCI‐No domain comparison varying the most (Table 2). We limit interpretation to those regions that appeared in ≥70% of repetitions. The amygdala was consistently selected in all pair‐wise comparisons. Higher tau deposition in this region was associated with a higher likelihood of being in AD/MCI‐Memory. Higher tau deposition in the postcentral region was associated with a lower likelihood of being in AD/MCI‐Memory compared to AD/MCI‐Visuospatial. Coefficients on consistently selected regions in the AD/MCI‐visuospatial versus AD/MCI‐No domain comparison were small. Figure 1 summarizes the top results from our analyses. Conclusion: We found heterogeneity in regional tau deposition among three cognitive subtypes. Future work will make use of additional cohorts with harmonized cognitive and imaging data. We plan to incorporate all cognitive subtypes and evaluate lateral asymmetry.Item The prevalence of tau‐PET positivity in aging and dementia(Wiley, 2025-01-09) Coomans, Emma M.; Groot, Colin; Rowe, Christopher C.; Dore, Vincent; Villemagne, Victor L.; van de Giessen, Elsmarieke; van der Flier, Wiesje M.; Pijnenburg, Yolande A. L.; Visser, Pieter Jelle; den Braber, Anouk; Pontecorvo, Michael; Shcherbinin, Sergey; Kennedy, Ian A.; Jagust, William J.; Baker, Suzanne L.; Harrison, Theresa M.; Gispert, Juan Domingo; Shekari, Mahnaz; Minguillon, Carolina; Smith, Ruben; Mattsson-Carlgren, Niklas; Palmqvist, Sebastian; Strandberg, Olof; Stomrud, Erik; Malpetti, Maura; O'Brien, John T.; Rowe, James B.; Jäger, Elena; Bischof, Gérard N.; Drzezga, Alexander; Garibotto, Valentina; Frisoni, Giovanni; Peretti, Débora Elisa; Schöll, Michael; Skoog, Ingmar; Kern, Silke; Sperling, Reisa A.; Johnson, Keith A.; Risacher, Shannon L.; Saykin, Andrew J.; Carrillo, Maria C.; Dickerson, Brad C.; Apostolova, Liana G.; Barthel, Henryk; Rullmann, Michael; Messerschmidt, Konstantin; Vandenberghe, Rik; Van Laere, Koen; Spruyt, Laure; Franzmeier, Nicolai; Brendel, Matthias; Gnörich, Johannes; Benzinger, Tammie L. S.; Lagarde, Julien; Sarazin, Marie; Bottlaender, Michel; Villeneuve, Sylvia; Poirier, Judes; Seo, Sang Won; Gu, Yuna; Kim, Jun Pyo; Mormino, Elizabeth; Young, Christina B.; Vossler, Hillary; Rosa-Neto, Pedro; Therriault, Joseph; Rahmouni, Nesrine; Coath, William; Cash, David M.; Schott, Jonathan M.; Rabinovici, Gil D.; La Joie, Renaud; Rosen, Howard J.; Johnson, Sterling C.; Christian, Bradley T.; Betthauser, Tobey J.; Hansson, Oskar; Ossenkoppele, Rik; Radiology and Imaging Sciences, School of MedicineBackground Tau‐PET imaging allows in‐vivo detection of neurofibrillary tangles. One tau‐PET tracer (i.e., [18F]flortaucipir) has received FDA‐approval for clinical use, and multiple other tau‐PET tracers have been implemented into clinical trials for participant selection and/or as a primary or secondary outcome measure. To optimize future use of tau‐PET, it is essential to understand how demographic, clinical and genetic factors affect tau‐PET‐positivity rates. Method This large‐scale multi‐center study includes 9713 participants from 35 cohorts worldwide who underwent tau‐PET with [18F]flortaucipir (n = 6420), [18F]RO948 (n = 1999), [18F]MK6240 (n = 878) or [18F]PI2620 (n = 416) (Table‐1). We analyzed individual‐level tau‐PET SUVR data using a cerebellar reference region that were processed either centrally (n = 3855) or by each cohort (n = 5858). We computed cohort‐specific SUVR thresholds based on the mean + 2 standard deviations in a temporal meta‐region of amyloid‐negative cognitively normal (CN) individuals aged >50. Logistic generalized estimating equations were used to estimate tau‐PET‐positivity probabilities, using an exchangeable correlation structure to account for within‐cohort correlations. Analyses were performed with (interactions between) age, amyloid‐status, and APOE‐e4 carriership as independent variables, stratified for syndrome diagnosis. Result The study included 5962 CN participants (7.5% tau‐PET‐positive), 1683 participants with mild cognitive impairment (MCI, 33.8% tau‐PET‐positive) and 2068 participants with a clinical diagnosis of dementia (62.1% tau‐PET‐positive) (Figure‐1). From age 60 to 80 years, the estimated prevalence of tau‐PET‐positivity increased from 1.2% [95% CI: 0.9%‐1.5%] to 3.7% [2.3%‐5.1%] among CN amyloid‐negative participants; and from 16.4% [10.8%‐22.1%] to 20.5% [18.8%‐22.2%] among CN amyloid‐positive participants. Among amyloid‐negative participants with MCI and dementia, from age 60 to 80 years, the estimated prevalence of tau‐PET‐positivity increased from 3.5% [1.6%‐5.3%] to 11.8% [7.1%‐16.5%] and from 12.6% [4.5%‐20.7%] to 15.9% [6.7%‐25.1%] respectively. In contrast, among amyloid‐positive participants with MCI and dementia, from age 60 to 80 years, the estimated prevalence of tau‐PET‐positivity decreased from 66.5% [57.0%‐76.0%] to 48.3% [42.9%‐53.8%] and from 92.3% [88.7%‐95.9%] to 73.4% [67.5%‐79.3%] respectively. APOE‐e4 status primarily modulated the association of age with tau‐PET‐positivity estimates among CN and MCI amyloid‐positive participants (Figure‐2). Conclusion This large‐scale multi‐cohort study provides robust prevalence estimates of tau‐PET‐positivity, which can aid the interpretation of tau‐PET in the clinic and inform clinical trial designs.