Factors associated with neuropsychological performance in HIV-seropositivesubjects without AIDS

Background. Previous research has suggested that several factors may influe nce the presence of cognitive impairment in human immunodeficiency virus (H IV) infection. The objective of this study was to assess the impact of cogn itive reserve capacity anti other variables on neuropsychological performan ce in early HIV infection. Methods. The neuropsychological performance of 100 HIV-seropositive subject s without AIDS (71 men and 29 women) was compared with that of 63 seronegat ive controls (51 men and 12 women). Measures included a neuropsychological battery, a medical examination and a psychiatric assessment. Cognitive rese rve scores were based on a combination of years in school, a measure of edu cational achievement, and an estimate of pre-morbid intelligence. Results. HIV-positive subjects had longer reaction time latencies than HIV- negative subjects. Those in the HIV-positive group with low cerebral reserv e scores showed the poorest performance on the neuropsychological tests. Th e prevalence of cognitive impairment was significantly higher in the HIV-po sitive group (27 %) than in the controls (3.2 %). Multiple regression analy sis and logistic regression analysis were used to identify factors associat ed with global neuropsychological performance and cognitive impairment. Old er age, lower cerebra] reserve scores and not being on zidovudine treatment were associated with lower global neuropsychological scores and with the p resence of cognitive impairment. Conclusions. Our results suggest that although cognitive impairment is not characteristic of early HIV infection, there is a subgroup of subjects who perform more poorly than expected. A lower reserve capacity, older age and not being on zidovudine treatment are factors that lower the threshold for neuropsychological abnormalities in cases of early HIV infection.