Language deficits across PET‐based Braak stages of tau accumulation in Alzheimer's disease

INTRODUCTION: Language complaints in cognitively unimpaired (CU) individuals may reflect Alzheimer's Disease (AD) pathology and future objective impairments. METHODS: F-AZD-4694 amyloid-PET. Word-finding complaints, confrontation naming, semantic fluency, phonemic fluency and word-knowledge were evaluated. RESULTS: Complaints about forgetting the names of objects appeared in early tau stages (Braak 1-2), followed by naming difficulties (Braak 3-4), and widespread language impairments in later stages (Braak 5-6). Across the biologically-defined AD continuum, lower language performance was associated with tau accumulation predominantly in left-temporal language regions. In CU, only subjective word-finding complaints related to tau, indicating language concerns could reflect underlying pathology before measurable cognitive decline. DISCUSSION: Language measures support early detection and staging of AD pathophysiology and contribute to better align cognitive assessment with biological definitions of the disease.