Neuropsychological Impairment Among Asymptomatic HIV-Positive Former Intravenous Drug Users

Objective: To evaluate the influence of human immunodeficiency virus (HIV) infection and situation of drug consumption on neuropsychological impairment in asymptomatic HIV-positive (HIV+) former intravenous drug users (IVDUs) of Spanish nationality.
Background: Currently, we have no data about neuropsychological impairment in asymptomatic HIV+ IVDUs taking into account different situations of drug consumption.
Method: A neuropsychological evaluation was made of four groups of IVDUs: 33 abstinent HIV+ IVDUs, 21 methadone-maintained HIV+ IVDUs, 27 abstinent HIV-negative (HIV2) IVDUs, and 21 methadone-maintained HIV2 IVDUs. Their neuropsychological impairment rates were determined taking as a reference the performance of 23 HIV2 subjects without history of drug abuse.
Results: The rate of neuropsychological impairment of methadonemaintained HIV+ patients (48%) and that of those in abstinence (24%) is greater than that of HIV2 subjects in a similar condition (19% and 11%). The impairment rate of the methadone-maintained HIV+ group is significantly greater than that of the abstinent HIV+. Methadonemaintained HIV+ subjects with neuropsychological impairment have fewer education years than those not impaired; likewise, the percentages of subjects with significant immunodepression, detectable viral load, and without antiretroviral treatments are higher among methadonemaintained subjects with neuropsychological impairment.
Conclusions: This study emphasizes the association of asymptomatic HIVinfection with neuropsychological impairment in IVDUs and reveals the importance of the drug consumption situation in relation to this risk, being methadone-maintained IVDUs more likely to suffer from it. This fact seems to be related to the worsening of the infection and its treatment and to educational level.