HIV-Associated Neurocognitive Disorders (HAND): The View of a Psychiatrist

Abstract

HIV-associated neurocognitive disorders (HAND) are most commonly seen in the late symptomatic stage of HIV disease, i.e., “full-blown” AIDS. The Frascati Conference revision of the American Academy of Neurology criteria recognizes two clinical neurocognitive disorders: mild neurocognitive disorder (MND) and HIV-associated dementia (HAD). For a diagnosis of MND, there must be mild neurocognitive impairment in at least two domains of cognitive performance and, at most, a minor functional impairment in daily living, insufficient severity for a diagnosis of HAD, and no other known etiology for the symptoms. For a diagnosis of HAD, there must be severe cognitive impairment in two or more domains, at least a moderate level of functional status impairment due to the cognitive symptoms, a lack of clouding of consciousness (i.e., delirium), and no support for another etiology accounting for these symptoms. Cognitive deficits are expected to be established by formal neuropsychological testing. However, broad screening tests are frequently used in practice. HAD is an AIDS-defining diagnosis and may be the first symptom of infection in as many as 25% of patients. Both MND and HAD have been reported to have declined in incidence by as much as 50% since the introduction of effective antiretroviral therapy (ART). Yet, the frequency of HAND has remained similar to the eras prior to effective ART due to inclusion of the condition known as “asymptomatic neurocognitive impairment” (ANI) (or “sub-clinical” neurocognitive impairment). ANI occurs when there is significant cognitive decline in two or more domains of neuropsychological performance but no significant decline in functional status. It is estimated that ANI, as opposed to MND and HAD, has not significantly declined in prevalence in the HAART era.