Prevalence of CSF Alzheimer’s disease-like in middle-aged HIV+ individuals
The study aimed at determining the prevalence of Alzheimer’s disease (AD) risk in ageing and chronically HIV-infected (HIV+) persons who are successfully treated with combination antiretroviral therapy (cART). 43 adult males and 1 female with stable chronic HIV disease [aged 57 ± 8 years, HIV duration 20 (5-25) years, undetectable plasma and CSF HIV RNA] were enrolled under a prospective observational study. All underwent standard neuropsychological testing, APOE genotyping and a CSFlumbar puncture to assess CSF Aβ1-42, h-tau and p-tau concentrations.
To provide external CSF references, we tested 3 HIV-negative controls aged 64±2 and 5 AD patients aged 63±6 years. CSF was examined blind to the AD or HIV-associated neurocognitive disorder (HAND) status and vice versa. Risk for AD was evaluated using published cut-offs, which combines the three CSF biomarkers.
Based on the cut-offs: no elderly controls had a CSF-AD profile; all AD patients had at least one CSF-AD profile. Of the HIV+ individuals, 11.4% had a CSF-AD profile. Logistic regressions showed that APOE ε4/ε4 (p=0.03), having previously diagnosed severe HAND (p<0.03) and having lower current neurocognition (p<.002) were associated with a CSF-AD like profile.
Some patients with chronic HIV disease have 10-fold higher risk for AD based on CSF biomarkers, relative to the general population of the same age. However, it is not clear if this finding has the same clinical significance as in the general population. Known genetic factors for this age group were associated with a CSF-AD like profile, as well as past HAND and lower current neurocognition. Our research argues for renewed research effort to understand the consequences of brain ageing in HIV+ persons.
