MRI Signature of α-Synuclein Pathology in Asymptomatic Stages and a Memory Clinic Population
Authors: Wisse Laura E. M. , Spotorno Nicola , Rossi Marcello , Grothe Michel J. , Mammana Angela , Tideman Pontus , Baiardi Simone , Strandberg Olof , Ticca Alice , van Westen Danielle , Mattsson-Carlgren Niklas , Palmqvist Sebastian , Stomrud Erik , Parchi Piero , Hansson Oskar ,   Alzheimer’s Disease Neuroimaging Initiative, Weiner Michael W. , Aisen Paul , Petersen Ronald , Jack Clifford R. , Jagust William , Trojanowki John Q. , Toga Arthur W. , Beckett Laurel , Green Robert C. , Saykin Andrew J. , Morris John C. , Perrin Richard J. , Shaw Leslie M. , Khachaturian Zaven , Carrillo Maria , Potter William , Barnes Lisa , Bernard Marie , González Hector , Ho Carole , Hsiao John K. , Jackson Jonathan , Masliah Eliezer , Masterman Donna , Okonkwo Ozioma , Ryan Laurie , Silverberg Nina , Fleisher Adam , Sacrey Diana Truran , Fockler Juliet , Conti Cat , Veitch Dallas , Neuhaus John , Jin Chengshi , Nosheny Rachel , Ashford Miriam , Flenniken Derek , Kormos Adrienne , Montine Tom , Rafii Michael , Raman Rema , Jimenez Gustavo , Donohue Michael , Gessert Devon , Salazar Jennifer , Zimmerman Caileigh , Cabrera Yuliana , Walter Sarah , Miller Garrett , Coker Godfrey , Clanton Taylor , Hergesheimer Lindsey , Smith Stephanie , Adegoke Olusegun , Mahboubi Payam , Moore Shelley , Pizzola Jeremy , Shaffer Elizabeth , Sloan Brittany , Harvey Danielle , Forghanian-
Arani Arvin , Borowski Bret , Ward Chad , Schwarz Christopher , Jones David , Gunter Jeff , Kantarci Kejal , Senjem Matthew , Vemuri Prashanthi , Reid Robert , Fox Nick C. , Malone Ian , Thompson Paul , Thomopoulos Sophia I. , Nir Talia M. , Jahanshad Neda , DeCarli Charles , Knaack Alexander , Fletcher Evan , Tosun-Turgut Duygu , Chen Stephanie Rossi , Choe Mark , Crawford Karen , Yushkevich Paul A. , Das Sandhitsu , Koeppe Robert A. , Reiman Eric M. , Chen Kewei , Mathis Chet , Landau Susan , Cairns Nigel J. , Householder Erin , Franklin Erin , Bernhardt Haley , Taylor-
Reinwald Lisa , Korecka Magdalena , Figurski Michael , Neu Scott , Nho Kwangsik , Risacher Shannon L. , Apostolova Liana G. , Shen Li , Foroud Tatiana M. , Nudelman Kelly , Faber Kelley , Wilmes Kristi , Thal Leon , Silbert Lisa C. , Lind Betty , Crissey Rachel , Kaye Jeffrey A. , Carter Raina , Dolen Sara , Quinn Joseph , Schneider Lon S. , Pawluczyk Sonia , Becerra Mauricio , Teodoro Liberty , Dagerman Karen , Spann Bryan M. , Brewer James , Vanderswag Helen , Ziolkowski Jaimie , Heidebrink Judith L. , Zbizek-Nulph Lisa , Lord Joanne L. , Mason Sara S. , Albers Colleen S. , Knopman David , Johnson Kris , Villaneuva-
Meyer Javier , Pavlik Valory , Pacini Nathaniel , Lamb Ashley , Kass Joseph S. , Doody Rachelle S. , Shibley Victoria , Chowdhury Munir , Rountree Susan , Dang Mimi , Stern Yaakov , Honig Lawrence S. , Mintz Akiva , Ances Beau , Winkfield David , Carroll Maria , Stobbs-Cucchi Georgia , Oliver Angela , Creech Mary L. , Mintun Mark A. , Schneider Stacy , Geldmacher David , Love Marissa Natelson , Griffith Randall , Clark David , Brockington John , Marson Daniel , Grossman Hillel , Goldstein Martin A. , Greenberg Jonathan , Mitsis Effie , Shah Raj C. , Lamar Melissa , Samuels Patricia , Duara Ranjan , Greig-Custo Maria T. , Rodriguez Rosemarie , Albert Marilyn , Onyike Chiadi , Farrington Leonie , Rudow Scott , Brichko Rottislav , Kielb Stephanie , Smith Amanda , Raj Balebail Ashok , Fargher Kristin , Sadowski Martin , Wisniewski Thomas , Shulman Melanie , Faustin Arline , Rao Julia , Castro Karen M. , Ulysse Anaztasia , Chen Shannon , Sheikh Mohammed O. , Singleton-
Garvin Jamika , Doraiswamy P. Murali , Petrella Jeffrey R. , James Olga , Wong Terence Z. , Borges-Neto Salvador , Karlawish Jason H. , Wolk David A. , Vaishnavi Sanjeev , Clark Christopher M. , Arnold Steven E. , Smith Charles D. , Jicha Gregory A. , El Khouli Riham , Raslau Flavius D. , Lopez Oscar L. , Oakley MaryAnn , Simpson Donna M. , Porsteinsson Anton P. , Martin Kim , Kowalski Nancy , Keltz Melanie , Goldstein Bonnie S. , Makino Kelly M. , Ismail M. Saleem , Brand Connie , Thai Gaby , Pierce Aimee , Yanez Beatriz , Sosa Elizabeth , Witbracht Megan , Kelley Brendan , Nguyen Trung , Womack Kyle , Mathews Dana , Quiceno Mary , Levey Allan I. , Lah James J. , Hajjar Ihab , Cellar Janet S. , Burns Jeffrey M. , Swerdlow Russell H. , Brooks William M. , Silverman Daniel H.S. , Kremen Sarah , Tingus Kathleen , Lu Po H. , Bartzokis George , Woo Ellen , Teng Edmond , Graff-Radford Neill R. , Parfitt Francine , Poki-Walker Kim , Farlow Martin R. , Hake Ann Marie , Matthews Brandy R. , Brosch Jared R. , Herring Scott , van Dyck Christopher H. , Mecca Adam P. , Good Susan P. , MacAvoy Martha G. , Carson Richard E. , Varma Pradeep , Chertkow Howard , Vaitekunis Susan , Hosein Chris , Black Sandra , Stefanovic Bojana , Heyn Chris (Chinthaka) , Hsiung Ging-Yuek Robin , Kim Ellen , Mudge Benita , Sossi Vesna , Feldman Howard , Assaly Michele , Finger Elizabeth , Pasternak Stephen , Rachinsky Irina , Kertesz Andrew , Drost Dick , Rogers John , Grant Ian , Muse Brittanie , Rogalski Emily , Robson Jordan , Mesulam M.-Marsel , Kerwin Diana , Wu Chuang-Kuo , Johnson Nancy , Lipowski Kristine , Weintraub Sandra , Bonakdarpour Borna , Pomara Nunzio , Hernando Raymundo , Sarrael Antero , Rosen Howard J. , Miller Bruce L. , Perry David , Turner Raymond Scott , Johnson Kathleen , Reynolds Brigid , MCCann Kelly , Poe Jessica , Sperling Reisa A. , Johnson Keith A. , Marshall Gad A. , Yesavage Jerome , Taylor Joy L. , Chao Steven , Coleman Jaila , White Jessica D. , Lane Barton , Rosen Allyson , Tinklenberg Jared , Belden Christine M. , Atri Alireza , Clark Kelly A. , Zamrini Edward , Sabbagh Marwan , Killiany Ronald , Stern Robert , Mez Jesse , Kowall Neil , Budson Andrew E. , Obisesan Thomas O. , Ntekim Oyonumo E. , Wolday Saba , Khan Javed I. , Nwulia Evaristus , Nadarajah Sheeba , Lerner Alan , Ogrocki Paula , Tatsuoka Curtis , Fatica Parianne , Maillard Pauline , Olichney John , Carmichael Owen , Bates Vernice , Capote Horacio , Rainka Michelle , Borrie Michael , Lee T-Y , Bartha Rob , Johnson Sterling , Asthana Sanjay , Carlsson Cynthia M. , Perrin Allison , Burke Anna , Scharre Douglas W. , Kataki Maria , Tarawneh Rawan , Hart David , Zimmerman Earl A. , Celmins Dzintra , Miller Delwyn D. , Boles Ponto Laura L. , Smith Karen Ekstam , Koleva Hristina , Shim Hyungsub , Nam Ki Won , Schtulz Susan K. , Williamson Jeff D. , Craft Suzanne , Cleveland Jo , Yang Mia , Sink Kaycee M. , Ott Brian R. , Drake Jonathan , Tremont Geoffrey , Daiello Lori A. , Ritter Aaron , Bernick Charles , Munic Donna , O'Connell Abigail , Mintzer Jacobo , Wiliams Arthur , Masdeu Joseph , Shi Jiong , Garcia Angelica , Newhouse Paul , Potkin Steven , Salloway Steven , Malloy Paul , Correia Stephen , Kittur Smita , Pearlson Godfrey D. , Blank Karen , Anderson Karen , Flashman Laura A. , Seltzer Marc , Hynes Mary L. , Santulli Robert B. , Relkin Norman , Chiang Gloria , Lee Athena , Lin Michael , Ravdin Lisa , Sood Ajay , Blanchard Kimberly S. , Fleischman Debra , Arfanakis Konstantinos , Varon Daniel , Greig Maria T. , Goldstein Bonnie , Martin Kimberly S. , Reist Christopher , Sadowsky Carl , Martinez Walter , Villena Teresa , Rosen Howard , Marshall Gad , Peskind Elaine R. , Petrie Eric C. , Li Gail 
Published: July 2024

ImportanceThe lack of an in vivo measure for α-synuclein (α-syn) pathology until recently has limited thorough characterization of its brain atrophy pattern, especially during early disease stages.ObjectiveTo assess the association of state-of-the-art cerebrospinal fluid (CSF) seed amplification assays (SAA) α-syn positivity (SAA α-syn+) with magnetic resonance imaging (MRI) structural measures, across the continuum from clinically unimpaired (CU) to cognitively impaired (CI) individuals, in 3 independent cohorts, and separately in CU and CI individuals, the latter reflecting a memory clinic population.Design, Setting, and ParticipantsCross-sectional data were used from the Swedish BioFINDER-2 study (inclusion, 2017-2023) as the discovery cohort and the Swedish BioFINDER-1 study (inclusion, 2007-2015) and Alzheimer’s Disease Neuroimaging Initiative (ADNI; inclusion 2005-2022) as replication cohorts. All cohorts are from multicenter studies, but the BioFINDER cohorts used 1 MRI scanner. CU and CI individuals fulfilling inclusion criteria and without missing data points in relevant metrics were included in the study. All analyses were performed from 2023 to 2024.ExposuresPresence of α-syn pathology, estimated by baseline CSF SAA α-syn.Main Outcomes and MeasuresThe primary outcomes were cross-sectional structural MRI measures either through voxel-based morphometry (VBM) or regions of interest (ROI) including an automated pipeline for cholinergic basal forebrain nuclei CH4/4p (nucleus basalis of Meynert [NBM]) and CH1/2/3. Secondary outcomes were domain-specific cross-sectional cognitive measures. Analyses were adjusted for CSF biomarkers of Alzheimer pathology.ResultsA total of 2961 participants were included in this study: 1388 (mean [SD] age, 71 [10] years; 702 female [51%]) from the BioFINDER-2 study, 752 (mean [SD] age, 72 [6] years; 406 female [54%]) from the BioFINDER-1 study, and 821 (mean [SD] age, 75 [8] years; 449 male [55%]) from ADNI. In the BioFINDER-2 study, VBM analyses in the whole cohort revealed a specific association between SAA α-syn+ and the cholinergic NBM, even when adjusting for Alzheimer copathology. ROI-based analyses in the BioFINDER-2 study focused on regions involved in the cholinergic system and confirmed that SAA α-syn+ was indeed independently associated with smaller NBM (β = −0.271; 95% CI, −0.399 to −0.142; P &amp;lt;.001) and CH1/2/3 volumes (β = −0.227; 95% CI, −0.377 to −0.076; P =.02). SAA α-syn+ was also independently associated with smaller NBM volumes in the separate CU (β = −0.360; 95% CI, −0.603 to −0.117; P =.03) and CI (β = −0.251; 95% CI, −0.408 to −0.095; P =.02) groups. Overall, the association between SAA α-syn+ and NBM volume was replicated in the BioFINDER-1 study and ADNI cohort. In CI individuals, NBM volumes partially mediated the association of SAA α-syn+ with attention/executive impairments in all cohorts (BioFINDER-2, β = −0.017; proportion-mediated effect, 7%; P =.04; BioFINDER-1, β = −0.096; proportion-mediated effect, 19%; P =.04; ADNI, β = −0.061; proportion-mediated effect, 20%; P =.007).Conclusions and RelevanceIn this cohort study, SAA α-syn+ was consistently associated with NBM atrophy already during asymptomatic stages. Further, in memory clinic CI populations, SAA α-syn+ was associated with NBM atrophy, which partially mediated α-syn–induced attention/executive impairment.