Association of β-Amyloid Level, Clinical Progression, and Longitudinal Cognitive Change in Normal Older Individuals.
Laura M van der Kall, Thanh Truong, Samantha C Burnham, Vincent Doré, Rachel S Mulligan, Svetlana Bozinovski, Fiona Lamb, Pierrick Bourgeat, Jurgen Fripp, Stephanie Schultz, Yen Y Lim, Simon M Laws, David Ames, Christopher Fowler, Stephanie R Rainey-Smith, Ralph N Martins, Olivier Salvado, Joanne Robertson, Paul Maruff, Colin L Masters Show all
Neurology | Published : 2021
OBJECTIVE: To determine the effect of β-amyloid (Aβ) level on progression risk to mild cognitive impairment (MCI) or dementia and longitudinal cognitive change in cognitively normal (CN) older individuals. METHODS: All CN from the Australian Imaging Biomarkers and Lifestyle study with Aβ PET and ≥3 years follow-up were included (n = 534; age 72 ± 6 years; 27% Aβ positive; follow-up 5.3 ± 1.7 years). Aβ level was divided using the standardized 0-100 Centiloid scale: 100 CL very high, noting >25 CL approximates a positive scan. Cox proportional hazards analysis and linear mixed effect models were used to assess risk of progression and cognitive decline. RESULTS: Aβ levels in 63% were negative,..View full abstract