HIV-1 Induced CNS Dysfunction: Current Overview and Research Priorities

Background: Over the past three decades, the clinical presentation of HIV infection of the Central Nervous System (CNS) has evolved. Prior to wide spread use of effective antiretroviral therapy (ART), more than a third of infected individuals exhibited a range of neurocognitive and motor deficits that frequently progressed to severe dementia and paralysis. However, the use of ART has significantly decreased the prevalence of severe forms of HIV-1 associated neurocognitive disorders (HAND). Studies of neurocognitive dysfunction have reported variable prevalence, ranging from 21% to 77.6%, defined primarily by mild to moderate neurocognitive impairment. HIV-associated chronic inflammation and associated neurotoxicity of long term ART, as well as the aging of the HIV-infected population, likely influence the pathogenesis of HAND. Despite significant research efforts directed towards a better understanding of the mechanisms underlying HIV neuropathogenesis, definitive causal pathophysiology of HAND and thus effective prevention or treatment remain elusive. Furthermore, HIV therapeutic research now includes efforts to effect a cure, by eliminating or silencing HIV within infected cells, which must include efforts to target the latently infected cells within the CNS. Conclusion: Prevention and treatment of the neurological complications of HIV, and eradication of persistent virus from the CNS compartment are major priorities for the HIV-CNS research. Here we give an overview of the progress of research on HIV-CNS disease, define new challenges and research areas, and highlight domestic and global priorities.