In vivo assessment of amyloid-β deposition in nondemented very elderly subjects

• Published in: Annals of neurology Vol. 73; no. 6; pp. 751 - 761
• Main Authors: Mathis, Chester A., Kuller, Lewis H., Klunk, William E., Snitz, Beth E., Price, Julie C., Weissfeld, Lisa A., Rosario, Bedda L., Lopresti, Brian J., Saxton, Judith A., Aizenstein, Howard J., McDade, Eric M., Kamboh, M. Ilyas, DeKosky, Steven T., Lopez, Oscar L.
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01.06.2013
• Subjects: Adult; Aged; Aged, 80 and over; Amyloid beta-Peptides - metabolism; Aniline Compounds; Brain - metabolism; Brain - pathology; Cognitive Dysfunction - diagnosis; Cognitive Dysfunction - epidemiology; Cognitive Dysfunction - metabolism; Double-Blind Method; Female; Humans; Male; Middle Aged; Positron-Emission Tomography - methods; Prevalence; Thiazoles
• ISSN: 0364-5134; 1531-8249; 1531-8249
• DOI: 10.1002/ana.23797

Objective This study examined amyloid‐β (Aβ) deposition in 190 nondemented subjects aged ≥82 years to determine the proportion of Aβ‐positive scans and associations with cognition, apolipoprotein E (APOE) status, brain volume, and Ginkgo biloba (Gb) treatment. Methods Subjects who agreed to participate had a brain magnetic resonance imaging and positron emission tomography scan with 11C‐labeled Pittsburgh compound B (PiB) following completion of a Gb treatment clinical trial. The youngest subject in this imaging study was 82 years, and the mean age of the subjects was 85.5 years at the time of the scans; 152 (80%) were cognitively normal, and 38 (20%) were diagnosed with mild cognitive impairment (MCI) at the time of the PiB study. Results A high proportion of the cognitively normal subjects (51%) and MCI subjects (68%) were PiB‐positive. The APOE*4 allele was more prevalent in PiB‐positive than in PiB‐negative subjects (30% vs 6%). Measures of memory, language, and attentional functions were worse in PiB‐positive than in PiB‐negative subjects, when both normal and MCI cases were analyzed together; however, no significant associations were observed within either normal or MCI subject groups alone. There was no relationship between Gb treatment and Aβ deposition as determined by PiB. Interpretation The data revealed a 55% prevalence of PiB positivity in nondemented subjects age >80 years and 85% PiB positivity in the APOE*4 nondemented elderly subjects. The findings also showed that long‐term exposure to Gb did not affect the prevalence of cerebral Aβ deposition. ANN NEUROL 2013;73:751–761