Background: Prior studies have established that methamphetamine and HIV can have additive deleterious effects on neurocognitive functioning, but there has been relatively little research on other stimulants like cocaine. This study investigated the effects of cocaine and HIV on neurocognitive impairment in a large, well-characterized sample. Methods: The sample included 193 adults across four groups: HIV-positive cocaine users (n= 48), HIV-negative cocaine users (n= 53), HIV-positive non-drug users (n= 60), and HIV-negative non-drug users (n= 32). Cocaine users met criteria for lifetime dependence and had past-month cocaine use. A comprehensive battery assessed substance abuse and neurocognitive functioning. Results: Participants were mostly male (66%) and African-American (85%), with a mean age of 46.09 years. The rate of global impairment was 33%, with no significant main effects across groups on likelihood of impairment. There were main effects for cocaine on processing speed and executive functioning, with cocaine users having greater impairment (F= 9.33 and F= 4.22, respectively), and for HIV on attention, with HIV-infected persons having greater impairment (F= 5.55). There was an interaction effect for executive functioning, with the three patient groups having greater impairment than controls (F= 5.05). Nonparametric analyses revealed significant additive impairment in the presence of both HIV and cocaine for processing speed. Conclusions: While cocaine does not appear to increase vulnerability to global HIV-associated neurocognitive impairment, it does have independent adverse effects on executive functioning and processing speed. Given prior evidence that domain-specific deficits predict real-world impairments, our results may help explain the poorer behavioral and functional outcomes observed in HIV-infected cocaine users.
Bibliographical noteFunding Information:
This study was funded by grants K23-DA028660 , T32-AI007392 , and F31-DA035131 from the United States National Institutes of Health . We are grateful to the UNC Center for AIDS Research (P30-AI50410) for its assistance with patient recruitment. The NIH had no further role in study design, data collection, analysis and interpretation of data, writing the report, or in the decision to submit the paper for publication.
© 2015 Elsevier Ireland Ltd.
- Cocaine dependence
- Drug abuse
- HIV-associated neurocognitive disorders
- Neurocognitive impairment