Independent effects of HIV infection and cocaine dependence on neurocognitive impairment in a community sample living in the southern United States

Abstract

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.

Sex differences in HIV effects on visual memory among substance-dependent individuals

“…By contrast, we found no evidence of selective visual memory impairment among HIV+ cocaine-dependent men, consistent with previous reports of varying neurocognitive effects of cocaine use among primarily male HIV+ participant samples (Durvasula et al, 2000; Meade, Conn, Skalski, & Safren, 2011; but cf. Meade, Towe, Skalski, & Robertson, 2015). More basic and clinical studies are needed to characterize the increased risk of neurocognitive impairment among HIV+ cocaine-dependent women in more detail and to address the question of whether this vulnerability is HIV-specific; we note that regardless of HIV serostatus, women are more vulnerable to stimulant addiction than men: The addiction literature indicates that women escalate their use of stimulants more rapidly, and relapse more readily, than men (Becker & Hu, 2008; Greenfield, Back, Lawson, & Brady, 2010).…”

Dopamine Increases CD14+CD16+ Monocyte Transmigration across the Blood Brain Barrier: Implications for Substance Abuse and HIV Neuropathogenesis

“…Studies suggest that in some human immunodeficiency virus-1 (HIV) infected individuals, the development of HIV associated neurocognitive disorders (HAND) is accelerated and/or its severity increased with substance abuse, in the absence or presence of prescribed combination antiretroviral therapy (cART) (Rippeth et al, 2004; Hauser et al, 2007; Buch et al, 2012; Meyer et al, 2013; Weber et al, 2013; Meade et al, 2015). The mechanisms by which substance abuse contributes to HIV neuropathogenesis are not completely understood.…”

“…Substance abuse is also associated with poor adherence to prescribed cART (Arnsten et al, 2002; Hinkin et al, 2007) and with increased HIV neuropathogenesis (Rippeth et al, 2004; Hauser et al, 2007; Buch et al, 2012; Meyer et al, 2013; Weber et al, 2013; Meade et al, 2015). Drugs of abuse, including cocaine and methamphetamine, increase extracellular concentrations of dopamine in the CNS (Volkow et al, 2009).…”

Cocaine dependence does not contribute substantially to white matter abnormalities in HIV infection

“…A recent meta-analysis concluded that cocaine users perform worse than controls on a range of neuropsychological tests (Spronk et al , 2013). Moreover, prior studies have demonstrated that chronic cocaine use is associated with greater neurocognitive impairment in HIV-infected persons (Meade et al , 2011; Meade et al , 2015; Nath et al , 2001). DTI studies provide preliminary evidence that chronic cocaine use is associated with reduced FA, particularly in the corpus callosum and frontal and parietal lobes, but cocaine does not appear to affect MD (Kelly et al , 2011; Lane et al , 2010; Lim et al , 2002; Lim et al , 2008; Ma et al , 2009; Ma et al , 2015; Moeller et al , 2005; Moeller et al , 2007; Romero et al , 2010).…”