Decision making among HIV+ drug using men who have sex with men: A preliminary report from the Chicago Multicenter AIDS Cohort Study

Abstract

HIV+ substance-dependent individuals (SDIs) make significantly poorer decisions than HIV– SDIs, but the neurocognitive mechanisms underlying this impairment have not been identified. We administered the Iowa Gambling Task (IGT), a measure of decision making under uncertain risk, and the Cups Task, a measure of decision making under specified risk, to a group of 56 HIV+ and 23 HIV– men who have sex with men (MSMs) with a history of substance dependence enrolled in the Multicenter AIDS Cohort Study. The IGT provides no explicit information regarding the contingencies for each possible choice, and the probability of each outcome remains ambiguous at least for the early trials; in contrast, the Cups Task provides explicit information about the probability of each outcome. The HIV+ group made significantly poorer decisions on the IGT than the HIV– group. Cups Task performance did not differ significantly between HIV– and HIV+ groups. Exploratory analyses of the IGT data suggested that HIV+ subjects tended to perform more poorly during the early learning phase when uncertainty about specific outcomes was greatest. Additionally, performance on the final two trial blocks was significantly correlated with Stroop Interference scores, suggesting that IGT performance is driven increasingly by executive control during the later portion of the task. Potential cognitive mechanisms to be explored in later studies are discussed, including impairment in implicit learning processing.

Keywords:

• HIV
• Drug abuse
• Decision making
• Executive function
• AIDS
• Neurocognition

Acknowledgments

We thank Kate Lindsay, Carmon Houston, Theresa Keeley, Margarita Aguilar, Susheel Reddy, and John Phair. Supported by HHS R03 DA025977 to Eileen M. Martin. The Chicago Multicenter AIDS Cohort Study (MACS) is supported by UOI-AI-35039 (PI Steve Wolinsky).

Notes

¹This was with the exception of participants who tested positive for cannabis. This test result did not necessarily indicate use within 1–2 days prior to testing because of the longer time for elimination of THC metabolites.