Amyloid-β PET Positivity Among Cognitively Impaired People with HIV Over Age 60

We sought to characterize the frequency of amyloid-PET positivity among older cognitively impaired people with HIV (PWH) compared to cognitively unimpaired people without HIV (PWoH). We also examined the neuropsychological profiles of the PWH group by amyloid-PET status, cross-sectionally and longitudinally.

Virally suppressed PWH were sought for a study of HAND where amyloid-PET positivity was used to exclude the possibility of AD. Participants underwent a standardized neuropsychological battery to diagnose HAND. Age and sex-matched cognitively unimpaired PWoH were identified from a separate cohort at our site. No participant from either group showed clinical signs and symptoms in a pattern concerning for AD. All participants completed amyloid-PET ([18F]Florbetapir). A certified neurologist visually read these as amyloid positive (PET+) or negative (PET-).

Compared to cognitively unimpaired PWoH (n=65, mean age=67), the cognitively impaired PWH group (n=74, mean age=69) was predominantly male (94.6% vs. 72.3%, p<0.001), of non-hispanic white ethnicity (74.3% vs. 83.1%, p=0.211) and reported lower educational attainment (16.2 vs. 17.4 years, p<0.001). Among them, 6 (8.1%) had PET+ scans compared to 14 PWoH (21.5 %, p=0.024). Within the PWH group, we did not identify differences in the neuropsychological testing pattern by amyloid-PET status (all p-values >0.05).

Cognitively impaired PWH did not show increased frequency of amyloid positivity relative to cognitively unimpaired PWoH. Among PWH, cognitive performance did not differ by amyloid-PET status in analyses of cross-sectional baseline and longitudinal performance.