Citations

Clear

3217 citation(s) found for "Zhang, W".

Socioeconomic, racial-ethnic, household, and infrastructural disparities of hematologic cancer outcomes in the United States
Fei‐Zhang, David J. , Wu, Erik , Stanisic, Alexander , Hou, Lifang , Platanias, Leonidas C. , Ansell, Stephen M., Lewis‐Thames, Marquita W. , Badawy, Sherif M. , Stanisic, Alexander V , Paludo, Jonas , Badawy, Sherif M , Hou, Lifang , Fei-Zhang, David , Ansell, Stephen M. , Paludo, Jonas

Mayo Clinic

Blood Advances | January 14, 2025 | Volume: 9 | Issue: 6 | Pages: 1463-1471

10.1182/bloodadvances.2024013956 | PMID 39808792 Get It

Abstract Although social determinants of health (SDoH) investigations have shown limited analyses of socioeconomic and race-ethnic status on certain hematologic malignancies, the impact of factors beyond those across a fuller scope of hematologic cancers remains unknown. The Social Vulnerability Index (SVI), a tool for assessing varied US census–derived sociodemographic factors, allows for the specific quantification of SDoH in dynamic, regional contexts for their associations with hematologic malignancy inequities. To assess the summative influence of varied SDoH factors on hematologic malignancy outcomes and discern which SDoH factors contributed the largest associations toward disparities, 796 005 adults with hematologic malignancies between 1975 to 2017 were identified for this retrospective cohort study. Vulnerability in 15 SDoH factors was measured using composite and subcategory SVI scores geographically matched to patients. Regressions between SVI factors and follow-up time after diagnosis and survival period were performed. Increasing overall SVI correlated with significantly decreased surveillance period in 11 of 14 hematologic malignancies, with decreases upward of 33.4% (39.0-26.0 months for acute lymphocytic leukemia). Increasing SVI significantly associated with decreased survival period across 11 of 14 hematologic malignancies, with decreases upward of 47.2% (89.5-47.3 months for Hodgkin lymphoma). Socioeconomic status and housing and transportation vulnerabilities showed the largest magnitude of contributions, followed by minority language and household composition. Significant decreases in hematologic malignancy prognosis associate with increasing overall SDoH vulnerability in varied sociodemographic contexts in the United States. Furthermore, there are quantifiable differences in which types of SDoH contribute more to trends per malignancy type. These findings demonstrate specific SDoH targets for further research and policy initiatives to combat hematologic malignancy disparity more effectively.
TDP‐43 Cryptic RNAs in Perry Syndrome: Differences across Brain Regions and TDP‐43 Proteinopathies
Pickles, Sarah , Bejarano, Jesús González , Narayan, Anand, Daughrity, Lillian M. , Cidfuentes, Candela Maroto, Reeves, Madison M., Yue, Mei, Otero, Paula Castellanos, Ayuso, Virginia Estades, Dunmore, Judy H., Song, Yuping , Tong, Jimei, DeTure, Michael , Rawlinson, Bailey, Castanedes‐Casey, Monica , Dulski, Jarosław , Cerquera‐Cleves, Catalina , Zhang, Yong‐Jie , Josephs, Keith A. , Petrucelli, Leonard , Prudencio, Mercedes , Pickles, Sarah R , Bejarano, Jesus Gonzalez , Daughrity, Lillian, Maroto Cidfuentes, Candela, Castellanos Otero, Paula, Estades Ayuso, Virginia, Dunmore, Judy, Wszolek, Z.K. , Prudencio, Mercedes , Zhang, Yong-Jie , Dulski, Jaroslaw , Estades Ayuso, Virginia , Narayan, Anand, Reeves, Madison M., Dickson, Dennis W. , Wszołek, Zbigniew K.

Mayo Clinic

Movement Disorders | January 9, 2025 | Volume: 40 | Issue: 4 | Pages: 662-671

10.1002/mds.30104 | PMID 39788898 Get It

Abstract Background Perry syndrome (PS) is a rare and fatal hereditary autosomal dominant neurodegenerative disorder caused by mutations in dynactin ( DCTN1 ). PS brains accumulate inclusions positive for ubiquitin, transactive‐response DNA‐binding protein of 43 kDa (TDP‐43), and to a lesser extent dynactin. Objectives Little is known regarding the contributions of TDP‐43, an RNA binding protein that represses cryptic exon inclusion, in PS. Therefore, we sought to identify the degree of TDP‐43 dysfunction in two regions of PS brains. Methods We evaluated the levels of insoluble pTDP‐43 and TDP‐43‐regulated cryptic RNAs and protein in the caudate nucleus and substantia nigra of 7 PS cases, 12 cases of frontotemporal lobar degeneration (FTLD) with TDP‐43 pathology, and 11 cognitively healthy controls without TDP‐43 pathology. Results Insoluble pTDP‐43 protein levels were detected in PS brains to a similar extent in the caudate nucleus and substantia nigra but lower than those in FTLD brains. The caudate nucleus of PS showed accumulation of eight TDP‐43‐regulated cryptic RNAs ( ACTL6B , CAMK2B , STMN2 , UNC13A , KCNQ2 , ATG4B , GPSM2 , and HDGFL2 ) and cryptic protein (HDGFL2) characteristic of FTLD. Conversely, only one cryptic target, UNC13A , reached significance in the substantia nigra despite similar pTDP‐43 levels. Conclusion We detected TDP‐43 cryptic RNAs and protein in PS caudate nucleus. Given the importance of cryptic exon biology in the development of biomarkers, and the identification of novel targets for therapeutic intervention, it is imperative we understand the consequences of TDP‐43 dysfunction across different brain regions and determine the targets that are specific and common to TDP‐43 proteinopathies. © 2025 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
Characterization of the heterogeneity of amyloid‐PET‐negative patients with a clinical diagnosis of sporadic early‐onset AD: an FDG‐PET study in the LEADS cohort
Zhang, Jiaxiuxiu, Soleimani‐Meigooni, David N. , Zeltzer, Ehud , Windon, Charles , Hammers, Dustin B. , Eloyan, Ani , Touroutoglou, Alexandra , Apostolova, Liana G. , Windon, Charles , Lagarde, Julien , Schonhaut, Daniel R. , Maiti, Piyush , Zhang, Jiaxiuxiu, Hammers, Dustin B , Dage, Jeffrey L. , Nudelman, Kelly , Koeppe, Robert A. , Carrillo, María C. , Vemuri, Prashanthi , Dickerson, Bradford Clark , Rabinovici, Gil D. , Joie, Renaud La

Mayo Clinic

Alzheimer's & Dementia | January 9, 2025 | Volume: 20 | Issue: S2 | Pages: No page available

10.1002/alz.092804 Get It

AbstractBackgroundDiagnosing sporadic early‐onset AD (EOAD, age‐at‐onset<65) is challenging: in the multi‐center Longitudinal Early‐onset Alzheimer’s Disease Study, ∼25% of patients with clinically diagnosed EOAD are amyloid‐PET‐negative. Here we used FDG‐PET to characterize the heterogeneity of hypometabolic profiles in these patients and better identify underlying etiologies.MethodSeventy‐four amyloid‐PET‐negative patients with clinical diagnosis of sporadic EOAD (MCI or mild dementia stage) underwent FDG‐PET. Patients were classified as having normal or hypometabolic FDG‐PET based on a data‐driven approach that compared each patient to a group of 61 age‐matched amyloid‐PET‐negative controls using 12 methodological combinations (3 reference regions, 2 voxel‐level thresholds, 2 outlier detection methods). We then assessed clinical and demographic differences between patients with normal versus hypometabolic FDG‐PET, and further compared groups using independent biomarkers of neurodegeneration (structural MRI and fluid biomarkers). Finally, we applied hierarchical clustering to hypometabolic FDG‐PET scans to identify patterns of hypometabolism.ResultThirty‐six amyloid‐negative patients (49%) had hypometabolic FDG‐PET scans. They were older and more severely impaired across most cognitive domains than patients with normal FDG‐PET (Table 1). They also had reduced hippocampal volumes and cortical thickness (Figure 1A), higher plasma and CSF neurofilament light chain (NfL) levels, and elevated plasma GFAP compared to patients with normal FDG‐PET (Figure 1B). In contrast, the latter, who had intermediate cognitive scores between hypometabolic patients and controls, had MRI and fluid biomarker levels in the range of controls (Figure 1). In hypometabolic patients, hierarchical clustering identified four profiles: i) anterior temporal extending to temporo‐parietal and frontal regions (n=5), ii) anterior temporal and orbitofrontal (n=11), iii) occipito‐parietal (n=6), and iv) lateral frontal and parietal (n=14) (Figure 2). Genetic testing identified two patients with Frontotemporal Lobar Degeneration (FTLD)‐associated pathogenic variants, both considered hypometabolic and assigned to the first (MAPT) and second (c9orf72) metabolic profiles.ConclusionFifty‐one percent of amyloid‐negative patients had normal FDG‐PET: they had milder clinical impairment, normal MRI measures, and normal NfL values, suggesting non‐neurodegenerative etiologies. Patients with abnormal FDG showed heterogeneous hypometabolic patterns suggestive of multiple etiologies including Lewy body disease, FTLD or corticobasal degeneration. Longitudinal follow‐up to autopsy will ultimately clarify the amyloid‐negative clinical mimics of sporadic EOAD.
Proteomic Analysis Resolves Distinct Molecular Signatures in Alzheimer’s Disease Brain Across Diverse Racial Groups
Fox, Edward J., Liu, Yue , Modeste, Erica , Duong, Duc M. , Yin, Luming, Gearing, Marla , Reddy, Joseph S. , Allen, Mariet , Quicksall, Zachary , Scanlan, Jo, Linden, Abby Vander , Poehlman, William L. , Chen, Xianfeng , Baheti, Saurabh , Ho, Charlotte C.G. , Nguyen, Thuy , Yepez‐Sisalema, Geovanna, Mitchell, Adriana O., Oatman, Stephanie R., Carrasquillo, Minerva M. , Beach, Thomas G., Golde, Todd E. , Haroutunian, Vahram, Zhang, Bin , Jager, Philip L. De , Ertekin‐Taner, Nilüfer , Seyfried, Nicholas T. , Disease, Accelerating Medicine Partnership for Alzheimer’s (AMP‐AD) Diversity Initiative, Seifar, Fatemeh , Shantaraman, Anantharaman , Lah, James J. , Heath, Laura , Wang, Erming , Wang, Minghui , Wang, Xue , Carrasquillo, Minerva M. , Runnels, Alexi , Beach, Thomas G. , Barnes, Lisa L. , Haroutunian, Vahram , Soni, Rajesh K , Greenwood, Anna, Levey, Allan I. , Wingo, Aliza P. , Wingo, Thomas S , Disease, Accelerating Medicine Partnership for Alzheimer’s (AMP‐AD) Diversity Initiative

Mayo Clinic

Alzheimer's & Dementia | January 9, 2025 | Volume: 20 | Issue: S2 | Pages: No page available

10.1002/alz.092542 Get It

AbstractBackgroundAlzheimer's disease (AD) is the most prevalent neurodegenerative disease, yet our comprehension predominantly relies on studies within the non‐Hispanic White (NHW) population. To address this, Accelerating Medicines Partnership in AD (AMP‐AD) aimed to promote inclusivity in multi‐omics AD research, to unravel unique molecular signatures and pathways. The study aimed to provide comprehensive insights into the proteomic landscape of AD across diverse racial groups.MethodDorsolateral prefrontal cortex (DLPFC) and superior temporal gyrus (STG) brain tissues were donated from multiple centers (Mayo Clinic, Emory University, Rush University, Mt. Sinai School of Medicine) and were harmonized through neuropathological evaluation, specifically adhering to the Braak staging and CERAD criteria. Among 1105 DLPFC tissue samples (980 unique individuals), 322 were from African American donors, 214 from Latino Americans, 551 from NHW donors, and the rest were from a mixed or unknown racial background. Among 280 STG samples, 86 were African American, 76 Latino American, 116 NHW and the rest were mixed or unknown ethnicity. All tissues were uniformly homogenized and analyzed by tandem mass tag‐based mass spectrometry (TMT‐MS). Following quality control (QC), proteins with more than 50% missing values were removed and iterative principal component analysis was conducted to remove outliers within brain regions. Differential protein expression was conducted within and across races after adjusting for batch using regression‐analysis.ResultIn total, 9,180 proteins from the DLPFC, and 9,734 proteins from STG brain tissues were quantified by TMT‐MS. Further analysis identified approximately 3,000 differentially abundant proteins in AD brains compared to controls within race. The AD‐associated differentially abundant proteins were strongly correlated between DLPFC and STG regions and with CERAD and Braak. Protein levels of MAPT and APP demonstrated equivalent disease‐related elevations in both African American and NHW individuals with AD. Notably, after adjusting for AD, significant differences in protein levels were identified across race.ConclusionThe proteomics approach employed by AMP‐AD sheds light on the brain proteome in AD across diverse racial groups, emphasizing the importance of inclusive research in establishing robust and generalizable discoveries. The identified proteins here could underscore racial disparities beyond disease association, contributing to a more nuanced understanding of AD pathophysiology.
ATP1A3 as a target for isolating neuron‐specific extracellular vesicles from human brain and biofluids
Zhang, Zhengrong , Sultana, Nadia , Martens, Yuka A. , Sun, Min , Kanekiyo, Takahisa , Ikezu, Seiko , You, Yang , Sultana, Nadia, Ericsson, Maria , Ikezu, Tsuneya , Shaffer, Scott A.

Mayo Clinic

Alzheimer's & Dementia | January 9, 2025 | Volume: 20 | Issue: S2 | Pages: No page available

10.1002/alz.088090 Get It

AbstractBackgroundNeuron‐derived extracellular vesicles (NDEVs) are a valuable resource for understanding brain conditions and discovering neurodegenerative diseases biomarkers, notably Alzheimer’s disease (AD). Recent interest focuses on capturing neuron‐specific EVs from patient‐derived samples, characterizing their contents as a pathological reflection of the central nervous system (CNS). Our recent study identified ATPase Na+/K+ Transporting Subunit Alpha 3 (ATP1A3) as a prevalent neuron‐specific EV marker specifically expressed in brains. This study systematically analyzes neuronal EVs to assess the specificity of ATP1A3 to NDEVs and its potential as a target for NDEV pulldown from accessible biofluids for disease monitoring. Additionally, ATP1A3 is compared with other proposed NDEV markers.MethodWe applied immunoelectron microscopy to detect ATP1A3, L1 cell adhesion molecule (L1CAM) and neural cell adhesion molecule 1 (NCAM1) in EVs isolated from iPSC‐derived excitatory neurons, brain tissue, cerebrospinal fluid (CSF) and plasma. Neuronal EV enrichment was achieved through immunoaffinity isolation, utilizing anti‐ATP1A3, L1CAM and NCAM1 antibodies separately. Evaluation involved quantitative mass‐spectrometry, immunoblotting and ELISA. To compare the enrichment of neuronal markers, EVs isolated from CSF and plasma samples were analyzed using ExoView and Nanoimager. Additionally, we investigated the potential of ATP1A3+ plasma EVs as AD biomarker by comparing the value of amyloid‐beta peptide (Aβ) in ATP1A3+ plasma EVs measured by Nanoimager and other plasma AD biomarkers as determined by SIMOA.ResultATP1A3, identified as a neuron‐specific protein, exhibits substantial enrichment in NDEVs isolated from induced human neurons, brain tissue, CSF, and plasma samples, surpassing NCAM1 or L1CAM. Both single‐ and bulk‐EV analysis consistently demonstrate a higher enrichment of ATP1A3 associated EVs in human samples. Immunoprecipitation of ATP1A3+ EVs from human brain tissues reveals superior neuronal cell‐type specificity over NCAM1+ and L1CAM+ EVs by label‐free mass spectrometry. Increased Aβ levels are observed in ATP1A3+ EVs derived from CSF and plasma of AD cases by SIMOA. Moreover, Aβ+ populations in ATP1A3+ EVs from plasma can distinguish AD from mild cognitive impairment and control cases via Nanoimager compared to the conventional quantification of AD markers.ConclusionOur findings demonstrate that ATP1A3 as a promising target for isolating NDEVs from biofluids, offering potential diagnostic advancements in neurological research.
Amyloid‐PET in patients with a clinical diagnosis of sporadic early‐ versus late‐onset AD: comparison of the LEADS and ADNI cohorts
Zhang, Jiaxiuxiu, Soleimani‐Meigooni, David N. , Zeltzer, Ehud , Windon, Charles , Hammers, Dustin B. , Eloyan, Ani , Landau, Susan, Touroutoglou, Alexandra , Apostolova, Liana G. , Windon, Charles , Lagarde, Julien , Maiti, Piyush , Schonhaut, Daniel R. , Zhang, Jiaxiuxiu, Raya, Maison Abu , Vrillon, Agathe , Hammers, Dustin B , Dage, Jeffrey L. , Nudelman, Kelly , Koeppe, Robert A. , Carrillo, María C. , Vemuri, Prashanthi , Dickerson, Bradford Clark , Rabinovici, Gil D. , Joie, Renaud La

Mayo Clinic

Alzheimer's & Dementia | January 9, 2025 | Volume: 20 | Issue: S2 | Pages: No page available

10.1002/alz.092903 Get It

AbstractBackgroundLarge‐scale studies comparing sporadic early‐onset AD (EOAD, age<65) and late‐onset AD (LOAD, age≥65) are lacking. We compared amyloid‐PET outcomes (positivity rate and amyloid burden) between patients clinically diagnosed with sporadic EOAD vs LOAD, leveraging data from the Longitudinal Early‐Onset AD Study (LEADS) and the Alzheimer’s Disease Neuroimaging Initiative 3 (ADNI3).Method731 patients meeting the 2011 NIA‐AA criteria for AD dementia or MCI were included (505 early‐onset from LEADS, 226 late‐onset from ADNI3, Table 1). All participants underwent amyloid‐PET with [18F]Florbetaben or [18F]Florbetapir. Amyloid positivity was centrally determined by a process involving a visual read by a trained expert and PET‐only quantification; in case of a discrepancy, a read from an independent physician acted as a tiebreaker. Logistic regressions in each cohort examined relations between amyloid positivity and age, sex, MMSE and APOE4 genotype. Amyloid burden was independently quantified in Centiloids using an MRI‐based pipeline. Mean Centiloids in LEADS and ADNI were compared with two‐way ANOVA, for visually positive and visually negative scans.ResultAmyloid positivity rate was higher in LEADS (76%) than ADNI (64%, p<0.001, Figure 1A). Lower MMSE and APOE4 genotype increased odds of amyloid positivity in both cohorts, although the APOE4 effect was stronger in ADNI than LEADS (OR=10.1 versus 2.4, p=0.007, Table 2). Amyloid positivity was more common in females across cohorts, but this effect was only statistically significant in LEADS (Table 2). Centiloids were bimodally distributed in both cohorts, although the separation between positive and negative scans was more prominent in LEADS (Figure 1B). Visually positive scans had significantly higher Centiloids in LEADS than in ADNI, whereas no cohort difference was observed for visually negative scans (Figure 1C). Sensitivity analyses showed that this effect was driven by patients with MCI (CDR≤0.5; Figure 1D‐E).ConclusionThe lower amyloid positivity rate in ADNI might be due to AD‐mimicking pathologies being more common at an older age. The higher amyloid burden in early‐onset, amyloid‐positive patients could reflect younger patients being diagnosed later in the disease course compared to typical, late‐onset patients. Alternatively, younger patients might tolerate higher neuropathology burden due to higher brain reserve or fewer co‐pathologies.
A Modified Mediterranean Ketogenic Diet reverses signatures and mitigates modifiable risk factors of Alzheimer’s disease
Schweickart, Annalise , Huynh, Kevin, Wang, Tingting , Mellett, Natalie A. , Shi, Pixu , Zemlin, Jasmine , Rahman, Gibraan , Panitchpakdi, Morgan , Meehan, Michael J. , Schimmel, Leyla , Blennow, Kaj, Blach, Colette , Dorrestein, Pieter C. , Krumsiek, Jan , Craft, Suzanne , Huynh, Kevin , Batra, Richa , Neth, Bryan J. , Martino, Cameron , Dilmore, Amanda Hazel , Giles, Corey , Duong, Thy , Shenhav, Liat , Zhang, Anru R. , Karu, Naama , West, Kiana , Weldon, Kelly C. , Register, Thomas C. , Arnold, Matthias , Meikle, Peter J. , Blennow, Kaj , Zetterberg, Henrik , Knight, Rob , Kaddurah‐Daouk, Rima

Mayo Clinic

Alzheimer's & Dementia | January 9, 2025 | Volume: 20 | Issue: S7 | Pages: No page available

10.1002/alz.089878 Get It

AbstractBackgroundAlzheimer’s disease (AD) is a neurodegenerative disorder with significant environmental factors, including diet, that influence its onset and progression. While the ketogenic diet (KD) holds promise in reducing metabolic risks and potentially affecting AD progression, only a few studies have explored the KD’s molecular impact for markers of AD therapeutic potential. The BEAM diet study simultaneously profiled the KD’s effect on the lipidome, blood and cerebrospinal metabolome, and microbiome of both cognitively impaired and cognitively normal individuals. The findings summarized here assess the biological impact of a Modified Mediterranean KD in the context of Alzheimer’s disease treatment and prevention.MethodBEAM involved participants at risk for AD, either cognitively normal or with mild cognitive impairment. The participants consumed both a modified Mediterranean‐ketogenic diet (MMKD) and the American Heart Association diet (AHAD) for 6 weeks each, separated by a 6‐week washout period. We employed HPLC‐MS/MS lipidomics profiling in plasma, nuclear magnetic resonance (NMR)‐based metabolomics to profile serum and CSF, and metagenomics profiling on fecal samples before and after each diet to assess dietary‐induced changes.ResultThe MMKD led to significant alterations in the blood, CSF, and microbiome. These changes included a global elevation across all plasmanyl and plasmenyl ether lipid species, improved modifiable risk factors, like increased HDL‐C and reduced BMI, the reversal of serum metabolic disturbances linked to AD such as an increase in valine levels, and a reduction in systemic inflammation. Leveraging prior clinical studies on AD (n = 1,912), we found that MMKD was inversely associated with the peripheral lipidomic signature of prevalent and incident AD. In the CSF, the MMKD was linked to modified amino acid levels and the breakdown of branched‐chain amino acids (BCAAs). Importantly, we observed a strong correlation between metabolic changes in the CSF and serum, suggesting a systemic regulation of metabolism. In addition, participants with MCI on the MMKD had lower levels of GABA‐producing microbes and GABA, and higher levels of GABA‐regulating microbes.ConclusionOur findings highlight that MMKD can improve AD‐related risk factors, reverse some metabolic disturbances associated with AD, and align metabolic changes across the blood‐CSF barrier.Funding: Alzheimer’s Gut Microbiome Project, NIA U19AG063744
Amyloid‐PET in patients with a clinical diagnosis of sporadic early‐ versus late‐onset AD: comparison of the LEADS and ADNI cohorts
Zhang, Jiaxiuxiu, Soleimani‐Meigooni, David N. , Zeltzer, Ehud , Windon, Charles , Hammers, Dustin B. , Eloyan, Ani , Landau, Susan, Touroutoglou, Alexandra , Apostolova, Liana G. , Windon, Charles , Lagarde, Julien , Maiti, Piyush , Schonhaut, Daniel R. , Zhang, Jiaxiuxiu, Raya, Maison Abu , Vrillon, Agathe , Hammers, Dustin B , Dage, Jeffrey L. , Nudelman, Kelly , Koeppe, Robert A. , Carrillo, María C. , Vemuri, Prashanthi , Dickerson, Bradford Clark , Rabinovici, Gil D. , Joie, Renaud La

Mayo Clinic

Alzheimer's & Dementia | January 9, 2025 | Volume: 20 | Issue: S9 | Pages: No page available

10.1002/alz.094101 Get It

AbstractBackgroundLarge‐scale studies comparing sporadic early‐onset AD (EOAD, age<65) and late‐onset AD (LOAD, age = 65) are lacking. We compared amyloid‐PET outcomes (positivity rate and amyloid burden) between patients clinically diagnosed with sporadic EOAD vs LOAD, leveraging data from the Longitudinal Early‐Onset AD Study (LEADS) and the Alzheimer’s Disease Neuroimaging Initiative 3 (ADNI3).Method731 patients meeting the 2011 NIA‐AA criteria for AD dementia or MCI were included (505 early‐onset from LEADS, 226 late‐onset from ADNI3, Table 1). All participants underwent amyloid‐PET with [18F]Florbetaben or [18F]Florbetapir. Amyloid positivity was centrally determined by a process involving a visual read by a trained expert and PET‐only quantification; in case of a discrepancy, a read from an independent physician acted as a tiebreaker. Logistic regressions in each cohort examined relations between amyloid positivity and age, sex, MMSE and APOE4 genotype. Amyloid burden was independently quantified in Centiloids using an MRI‐based pipeline. Mean Centiloids in LEADS and ADNI were compared with two‐way ANOVA, for visually positive and visually negative scans.ResultAmyloid positivity rate was higher in LEADS (76%) than ADNI (64%, p<0.001, Figure 1A). Lower MMSE and APOE4 genotype increased odds of amyloid positivity in both cohorts, although the APOE4 effect was stronger in ADNI than LEADS (OR = 10.1 versus 2.4, p = 0.007, Table 2). Amyloid positivity was more common in females across cohorts, but this effect was only statistically significant in LEADS (Table 2). Centiloids were bimodally distributed in both cohorts, although the separation between positive and negative scans was more prominent in LEADS (Figure 1B). Visually positive scans had significantly higher Centiloids in LEADS than in ADNI, whereas no cohort difference was observed for visually negative scans (Figure 1C). Sensitivity analyses showed that this effect was driven by patients with MCI (CDR = 0.5; Figure 1D‐E).ConclusionThe lower amyloid positivity rate in ADNI might be due to AD‐mimicking pathologies being more common at an older age. The higher amyloid burden in early‐onset, amyloid‐positive patients could reflect younger patients being diagnosed later in the disease course compared to typical, late‐onset patients. Alternatively, younger patients might tolerate higher neuropathology burden due to higher brain reserve or fewer co‐pathologies.
Characterization of the heterogeneity of amyloid‐PET‐negative patients with a clinical diagnosis of sporadic early‐onset AD: an FDG‐PET study in the LEADS cohort
Zhang, Jiaxiuxiu, Soleimani‐Meigooni, David N. , Zeltzer, Ehud , Windon, Charles , Hammers, Dustin B. , Eloyan, Ani , Touroutoglou, Alexandra , Apostolova, Liana G. , Windon, Charles , Lagarde, Julien , Schonhaut, Daniel R. , Maiti, Piyush , Zhang, Jiaxiuxiu, Hammers, Dustin B , Dage, Jeffrey L. , Nudelman, Kelly , Koeppe, Robert A. , Carrillo, María C. , Vemuri, Prashanthi , Dickerson, Bradford Clark , Rabinovici, Gil D. , Joie, Renaud La

Mayo Clinic

Alzheimer's & Dementia | January 9, 2025 | Volume: 20 | Issue: S9 | Pages: No page available

10.1002/alz.094087 Get It

AbstractBackgroundDiagnosing sporadic early‐onset AD (EOAD, age‐at‐onset<65) is challenging: in the multi‐center Longitudinal Early‐onset Alzheimer’s Disease Study, ∼25% of patients with clinically diagnosed EOAD are amyloid‐PET‐negative. Here we used FDG‐PET to characterize the heterogeneity of hypometabolic profiles in these patients and better identify underlying etiologies.MethodSeventy‐four amyloid‐PET‐negative patients with clinical diagnosis of sporadic EOAD (MCI or mild dementia stage) underwent FDG‐PET. Patients were classified as having normal or hypometabolic FDG‐PET based on a data‐driven approach that compared each patient to a group of 61 age‐matched amyloid‐PET‐negative controls using 12 methodological combinations (3 reference regions, 2 voxel‐level thresholds, 2 outlier detection methods). We then assessed clinical and demographic differences between patients with normal versus hypometabolic FDG‐PET, and further compared groups using independent biomarkers of neurodegeneration (structural MRI and fluid biomarkers). Finally, we applied hierarchical clustering to hypometabolic FDG‐PET scans to identify patterns of hypometabolism.ResultThirty‐six amyloid‐negative patients (49%) had hypometabolic FDG‐PET scans. They were older and more severely impaired across most cognitive domains than patients with normal FDG‐PET (Table 1). They also had reduced hippocampal volumes and cortical thickness (Figure 1A), higher plasma and CSF neurofilament light chain (NfL) levels, and elevated plasma GFAP compared to patients with normal FDG‐PET (Figure 1B). In contrast, the latter, who had intermediate cognitive scores between hypometabolic patients and controls, had MRI and fluid biomarker levels in the range of controls (Figure 1). In hypometabolic patients, hierarchical clustering identified four profiles: i) anterior temporal extending to temporo‐parietal and frontal regions (n = 5), ii) anterior temporal and orbitofrontal (n = 11), iii) occipito‐parietal (n = 6), and iv) lateral frontal and parietal (n = 14) (Figure 2). Genetic testing identified two patients with Frontotemporal Lobar Degeneration (FTLD)‐associated pathogenic variants, both considered hypometabolic and assigned to the first (MAPT) and second (c9orf72) metabolic profiles.ConclusionFifty‐one percent of amyloid‐negative patients had normal FDG‐PET: they had milder clinical impairment, normal MRI measures, and normal NfL values, suggesting non‐neurodegenerative etiologies. Patients with abnormal FDG showed heterogeneous hypometabolic patterns suggestive of multiple etiologies including Lewy body disease, FTLD or corticobasal degeneration. Longitudinal follow‐up to autopsy will ultimately clarify the amyloid‐negative clinical mimics of sporadic EOAD.