{"doi":"10.1002/alz.13693","title":"Diffusion MRI relates to plasma Aβ42/40 in PET negative participants without dementia","abstract":"INTRODUCTION: Magnetic resonance imaging (MRI) biomarkers are needed for indexing early biological stages of Alzheimer's disease (AD), such as plasma amyloid-β (Aβ42/40) positivity in Aβ positron emission tomography (PET) negative individuals. METHODS: Diffusion free-water (FW) MRI was acquired in individuals with normal cognition (NC) and mild cognitive impairment (MCI) with Aβ plasma-/PET- (NC = 22, MCI = 60), plasma+/PET- (NC = 5, MCI = 20), and plasma+/PET+ (AD dementia = 21) biomarker status. Gray and white matter FW and fractional anisotropy (FAt) were compared cross-sectionally and the relationships between imaging, plasma and PET biomarkers were assessed. RESULTS: Plasma+/PET- demonstrated increased FW (24 regions) and decreased FAt (66 regions) compared to plasma-/PET-. FW (16 regions) and FAt (51 regions) were increased in plasma+/PET+ compared to plasma+/PET-. Composite brain FW correlated with plasma Aβ42/40 and p-tau181. DISCUSSION: FW imaging changes distinguish plasma Aβ42/40 positive and negative groups, independent of group differences in cognitive status, Aβ PET status, and other plasma biomarkers (i.e., t-tau, p-tau181, glial fibrillary acidic protein, neurofilament light). HIGHLIGHTS: Plasma Aβ42/40 positivity is associated with brain microstructure decline. Plasma+/PET- demonstrated increased FW in 24 total GM and WM regions. Plasma+/PET- demonstrated decreased FAt in 66 total GM and WM regions. Whole-brain FW correlated with plasma Aβ42/40 and p-tau181 measures. Plasma+/PET- demonstrated decreased cortical volume and thickness.","journal":"Alzheimer s & Dementia","year":2024,"id":423638,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":23,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.6488,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2024-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":426994,"name":"Wei‐en Wang","orcid":"0000-0001-8555-9062","position":1,"is_corresponding":false},{"id":19442,"name":"David Loewenstein","orcid":"0000-0001-6788-2798","position":2,"is_corresponding":false},{"id":339499,"name":"Ranjan Duara","orcid":"0000-0001-8060-6309","position":3,"is_corresponding":false},{"id":767026,"name":"Glenn E. Smith","orcid":"0000-0003-1506-9484","position":4,"is_corresponding":false},{"id":380177,"name":"Karen N. McFarland","orcid":"0000-0002-9952-8678","position":5,"is_corresponding":false},{"id":310953,"name":"Melissa J. Armstrong","orcid":"0000-0002-2163-1907","position":6,"is_corresponding":false},{"id":1174117,"name":"Darren M. Weber","orcid":"0000-0002-4703-3403","position":7,"is_corresponding":false},{"id":1142165,"name":"Warren Barker","orcid":"0000-0003-2171-7142","position":8,"is_corresponding":false},{"id":432731,"name":"Stephen A. Coombes","orcid":"0000-0001-8616-5364","position":9,"is_corresponding":false},{"id":348661,"name":"David E. Vaillancourt","orcid":"0000-0002-5663-6476","position":10,"is_corresponding":false},{"id":491822,"name":"Jesse C. DeSimone","orcid":"0000-0002-3823-8765","position":0,"is_corresponding":true}],"reference_count":67,"raw_metadata":null,"created_at":"2026-07-19T01:58:01.889748Z","pmid":"38441274","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}