Cerebrospinal Fluid Iron Status Predicts Neurocognitive Performance Over Time in Adults with HIV

Iron homeostasis is essential for brain health, and iron is also required for HIV replication, but the role of iron is largely unexplored in HIV-associated neurocognitive disorders. These disorders remain extremely common in people with HIV, despite antiretroviral therapy capable of suppressing viral replication, and they involve damage to white matter tracts and synaptodendritic architecture in the brain. We hypothesized that cerebrospinal fluid (CSF) levels of iron and two proteins involved in iron delivery, mitochondrial function, and protection against iron-mediated oxidative stress (H-ferritin and transferrin) are associated with neurocognitive performance over time in adults with HIV. These CSF iron-related biomarkers were measured at baseline (entry) in 403 adults with HIV from a large, prospective observational study who underwent comprehensive neurocognitive assessments at 6-month intervals. All participants were assigned a Global Deficit Score (GDS) and neurocognitive change status (improving/stable/declining), compared to baseline, at each visit. Biomarker associations with change status, and GDS differences over 30, 36, and 42 months of follow-up, were evaluated by multivariable regression. GDS-defined neurocognitive impairment was present in 120 study participants at entry (29.8%); 73% were on antiretroviral therapy. Of 267 participants with longitudinal follow-up, 16% were improving neurocognitively, and 20% were declining at their last follow-up visit (median 36 months). In multivariable-adjusted analyses, higher baseline CSF H-ferritin predicted improving neurocognitive performance at the last assessment (p=0.029), and a better GDS over at least 30 months. Higher H-ferritin levels were also associated with better GDS-defined neurocognitive performance over 30, 36, and 42 months in virally suppressed individuals (p-values