Publication Abstract Display
Type: Published Abstract
Title: Learning impairments on the California Verbal Learning Test are related to methamphetamine abuse and HIV status.
Authors: Cherner M, Ellis R, Marcotte T, Heaton R, Grant I, and the HNRC Group
Year: 2000
Publication: Journal of the International Neuropsychological Society
Volume: 6 Issue: 2 Pages: 232
Abstract:Stimulant abuse and quinolinic acid (QA) are known to cause excitotoxic damage to the basal ganglia, through their actions on dopaminergic and NMDA receptors respectively. QA is an endogenous excitotoxic substance that is associated with inflammatory processes of the central nervous system and has been shown to be produced by macrophages of HIV infected persons. The present study examines per formance on a measure of learning and memory, the California Verbal Learning Test (CVLT), in persons infected with HIV, persons with a history of methamphetamine abuse, and persons with both HIV infection and methamphetamine abuse. Fifty-two study participants (10 HIV10 Meth1, 30 HIV10 Meth2, 6 HIV20 Meth1, and 8 HIV20 Meth2) were administered the CVLT as par t of a larger assessment battery at the HIV neurobehavioral Research Center in San Diego, CA. Meth1 participants had ceased using the drug at least 15 days prior to the assessment and showed negative urine toxicology screens. Groups did not differ with respect to age, education, or ethnic distribution. There was a greater propor tion of women in the HIV10 Meth2 group. Group differences on the various learning and memory measures of the CVLT were analyzed using ANOVA. The relationship of QA from cerebrospinal fluid (CSF ) and CVLT was examined with linear regression analysis. Significant group differences emerged on measures of Total Learning and Short Delay Free Recall, with trends in Short Delay Cued Recall, Long Delay Free Recall, and Long Delay Cued Recall. In every case, a stairstep effect was observed, with the HIV10 Meth1 group per forming worst, followed by the HIV20 Meth1, HIV10 Meth2, and the HIV20 Meth2 performing best. There were no significant group differences in recognition or discriminability measures. Levels of CSF QA also showed a stairstep increase, with the HIV10 Meth1 group showing highest levels followed by the HIV20 Meth1, HIV10 Meth2, and HIV20 Meth2. However, CSFQA levels were not independently related to per formance on the CVLT. Findings suggest a combined brain insult of HIV infection and methamphetamine abuse resulting in increasing impairments in learning and memory. Future studies need to address biological mechanisms and evidence of anatomical damage underlying these deficits.

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