In a cross-sectional study of aviremic neurocognitively impaired patients receiving protease inhibitors as triple-drug therapy (n = 30) or as monotherapy (n = 22), we found no statistically significant differences in the types of cognitive domains involved or severity of cognitive deficit. Cerebrospinal fluid concentrations of total proteins, total tau, myelin basic protein, neuron-specific enolase, β2 microglobulin, S100B protein, or prevalence of cerebrospinal fluid HIV-RNA detection by standard (6.3% vs 7.1% P = 1) or ultrasensitive assays (50% vs 71.4%, P = 0.28) were similar in both groups. These results do not suggest important differences in the pattern of neurocognitive impairment between groups receiving very different antiretroviral strategies.