Neurocognitive intra-individual variability within HIV+ adults with and without current substance use.

Objective: HIV infection and current substance use (SU) are linked to cognitive and functional deficits, yet findings on their combined effects are mixed. Neurocognitive intraindividual variability, measured as dispersion of scores across a neuropsychological battery, is associated with worse cognitive outcomes and functional deficits among HIV+ adults but has not been studied in the context of HIV+ adults with current SU. We hypothesized that, among HIV+ adults, current SU would be associated with greater dispersion, that greater dispersion would be associated with worse medication adherence, and that this relationship would be worse among substance users.