HIV-associated neurocognitive disorder

Abstract

Purpose of review HIV associated neurocognitive disease (HAND) is the most active topic for neuroAIDS investigations at present. Although impairment is mild in patients successfully treated with modern antiviral regimens, it remains an ongoing problem for HIV patients. It is important to update the emerging research concerning HAND. Recent findings The virus enters the brain during acute infection, with evidence for abnormal functioning that may occur early and often persists. Direct relationships with ongoing viral infection continue to be monitored, but chronic inflammation, often associated with monocytes and macrophages appear to be the most likely driver of cognitive dysfunction. Appreciation for cerebrovascular disease as a significant co-morbidity that is associated with cognitive deficits is increasing. Neuroimaging is actively being developed to address detection and measurement of changes in the brain. Optimal cART therapy has vastly improved neurologic outcomes, but so far has not been demonstrated to reverse the remaining mild impairment. Inflammatory and vascular mechanisms of cerebral dysfunction may need to be addressed to achieve better outcomes. Summary Ongoing research is required to improve neurological outcomes for persons living with HIV. It is likely that interventions beyond antiviral approaches will be required to control or reverse HAND.

Neurological complications of HIV infection in pre-HAART and HAART era: a retrospective study

“…We observed that in all our patients diagnosed with cognitive impairment the MRI findings were similar to those described in the literature in patients with HIV infection (cortical and subcortical atrophy, ventricular enlargement, confluent signal abnormalities within the deep white matter) [9,45]. Some authors reported volumetric changes in the cortical areas, basal ganglia and white matter in HIV-infected patients at different stages of their disease: these changes were more severe in most advanced stages but were evident even in asymptomatic individuals [46].…”

“…Moreover, there is no agreement in the literature about the best tools that must be used to identify such patients in terms of neuropsychological tests and of CSF or blood biomarkers and neuroimaging characteristics [9,37]. In the HAART era, the use of neuropsychometric performance testing is more challenging since the major aim is to identify patients with more subtle deficits [9]. Frequently used methods include versions of the Mini-mental Status Exam, the Montreal Cognitive Assessment, the composite Z scores of several brief neuropsychometric tests used in the AIDS Clinical Trials Group system, the International HIV dementia screen, and parts of CogState devices.…”

“…Moreover, there is no agreement in the literature about the best tools that must be used to identify such patients in terms of neuropsychological tests and of CSF or blood biomarkers and neuroimaging characteristics [9,37]. In the HAART era, the use of neuropsychometric performance testing is more challenging since the major aim is to identify patients with more subtle deficits [9].…”

“…This important change in the epidemiology of this condition led to a new classification of HIV neurocognitive disorders [5], where a new category was added (asymptomatic neurocognitive impairment, including patients with impairment in neuropsychological testing only). Although contributing to improved outcomes, HAART has not resulted in full protection of the nervous system; changes in the brain are now subtle and occur slowly, so the major challenge is to identify patients with initial cognitive deficit and to establish an optimum HAART regimen [9].…”

7T Brain MRS in HIV Infection: Correlation with Cognitive Impairment and Performance on Neuropsychological Tests

“…Combination antiretroviral therapy (cART) can improve cognitive performance and brain metabolism in some patients with HAND 2, 5, 6 . However, many antiretroviral drugs do not penetrate well into the central nervous system 7 , and neurocognitive deficits are reversed in many but not all patients 8, 9 . The prevalence of HAND in HIV positive (HIV+) individuals with advanced infection remains around 45-50%, and patients are now surviving for years with HIV infection and HAND as chronic conditions 10, 11 .…”