Neuropsychological Consequences of HIV and Drug Ause

Accurate assessment of the functional consequences of human immunodeficiency virus (HIV) infection and drugs of abuse are critical as large populations are afflicted with both. Both are interdependent epidemics with important socioeconomic consequences. Experimental studies in animal models and in vitro clearly indicate that HIV and drugs of abuse cause increased neurodegeneration, glial cell activation and enhanced HIV replication. Nevertheless, most epidemiological studies and neurocognitive studies from the pre-HAART era failed to show any evidence of combined effects of HIV and drugs of abuse. However, these studies provided valuable insight into potential confounding factors in the study of these populations and helped identify sensitive neurocognitive tests for this population. Recent studies show that there is a clear additive effect of the infection and several of the drugs of abuse, although each of the drugs of abuse may have different types of effects on the brain. We propose that future studies should identify neuroimaging and biological surrogate markers to monitor these populations and we discuss therapeutic strategies simultaneously aimed at treating drug addiction and providing neuroprotection.