HIV-associated neurocognitive disorders
HIV-associated neurocognitive disorders (HAND) span a spectrum from asymptomatic neurocognitive impairment to HIV-associated dementia, caused by chronic HIV infection and inflammation of CNS microglia, and occur regardless of antiretroviral treatment status; diagnosis is one of exclusion after ruling out opportunistic and metabolic causes of cognitive decline, and antiretroviral therapy initiation or optimization is the primary treatment, with efavirenz avoided for its neuropsychiatric effects.
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What this article covers
- Overview
HIV-associated neurocognitive disorders (HAND) is a spectrum of cognitive impairment caused by HIV infection of the central nervous system, ranging from asymptomatic neurocognitive impairment through…
- Epidemiology
Screening for cognitive impairment is recommended at entry into HIV care as a baseline against which later decline can be measured, and repeated in older adults, especially when concerns arise about adherence to care or ART.
- Risk factors
Chronic HIV infection itself, through ongoing low-grade CNS viral reservoir activity and microglial infection, independent of systemic virologic suppression.
- Pathophysiology
HIV enters the central nervous system early in infection via infected monocytes and lymphocytes that cross the blood-brain barrier, establishing infection of resident microglia and, to a lesser…
- Clinical features
Cognitive impairment ranging from subtle, subclinical deficits detectable only on formal neuropsychological testing to overt functional impairment in daily activities, reflecting the breadth of the…
- Differential diagnosis
CNS toxoplasmosis: headache, fever, and focal deficits with multiple ring-enhancing lesions on CT or MRI in a patient with a CD4 cell count under 100/microliter and positive Toxoplasma serology…
- Diagnosis
HIV-associated neurocognitive disorders is a diagnosis of exclusion, established only after ruling out opportunistic CNS infection, CNS malignancy, and other systemic, metabolic, substance-related…
- Management
First, if the patient is not already on antiretroviral therapy (ART), start it immediately with a standard three-drug regimen, for example bictegravir 50 mg/emtricitabine 200 mg/tenofovir alafenamide…
- Complications
Progression from milder cognitive impairment to HIV-associated dementia if untreated or if uncontrolled viral replication persists.
- Prognosis
ART is central to prognosis: initiation or optimization has a clear role in preventing progression to, and improving outcomes in, HIV-associated dementia.
- Prevention
Early diagnosis and prompt initiation of ART at the time of HIV diagnosis is the principal preventive strategy, limiting the duration and depth of CNS viral injury before treatment begins.
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