Abnormal contingent negative variation in HIV patients receiving antiretroviral therapy

Abstract

The contingent negative variation, an event-related potential related to neural activity in the frontal lobe and basal ganglia, neuropsychological tests and structural MRI were used to examine CNS function and structure in HIV-positive patients receiving antiretroviral therapy. Relative to controls, HIV patients had smaller thalamic volume and reduced late contingent negative variation amplitude that correlated with caudal atrophy. Behaviorally, viremic patients were more impaired than virally suppressed patients and controls on neuropsychological measures of psychomotor speed, selective attention and mental flexibility. These results suggest that antiretroviral therapy may not be effective in protecting cortical and subcortical structures against HIV-related neuropathology, regardless of immune function. However, the benefits of antiretroviral therapy on immune function appear to facilitate neurocognitive performance.

Fig. 1

CNV grand averages from the vertex and schematic of the S1–S2 reaction time task. Grand averages for HIV− controls are denoted by the thick solid line, HIV + viremic patients by the dotted line, and HIV + virally suppressed patients by the thin solid line. Note the late CNVamplitude reductions in HIV + patients.

Fig. 2

Relationship between late CNV amplitude (at Cz) and caudate volume in all HIV + patients (r =−0.49, p <0.03). Similar trends were also observed in viremic HIV patients (denoted by triangles) and virally suppressed HIV patients (denoted by circles).