Evidence implicating cocaine as a possible risk factor for HIV infection

Recent cocaine use and memory impairment in HIV

Both Human Immunodeficiency Virus (HIV) and cocaine use have been associated with impairment in neuropsychological functioning. The high comorbidity between HIV and cocaine use highlights the importance of ascertaining whether there is a compounding effect of cocaine use in individuals with HIV. Among neuropsychological domains impacted by HIV, verbal memory deficits have received substantial attention partly because they have been associated with declines in functional status in HIV positive individuals. We collected California Verbal Learning Test-II data from HIV participants who met lifetime diagnostic criteria of cocaine abuse and/or dependence (HIV/CocDx+, N = 80 & HIV/CocDx-, N = 30, respectively) and those with and without recent cocaine use, which was confirmed by toxicology analysis (HIV/Coc+, N = 56 & HIV/Coc-, N = 57, respectively). The Item Specific Deficit Approach (ISDA) was employed to determine any additional cocaine-associated deficits in encoding, consolidation, and retrieval, which attempts to control for potential confounding factors of memory such as attention. Using conventional methods of evaluating memory profiles, we found that the HIV/Coc + group demonstrated worse learning, immediate and delayed free recall, and recognition in contrast to the HIV/Coc - group; although using the ISDA, we found that encoding was the only significant difference between HIV/Coc + and HIV/Coc-participant, with HIV/Coc - performing better. Our data suggest that for individuals with HIV, cocaine use is associated with a temporary decline in verbal memory, is characterized by greater encoding deficits, and these effects may reduce with abstinence. Clinically, our findings suggest that reduced encoding is the likely contributor to verbal memory decline in HIV/Coc + and these effects are partially reversible-at least to the level of their HIV/Coc - counterparts.

The Longitudinal Effects of Non-injection Substance Use on Sustained HIV Viral Load Undetectability Among MSM and Heterosexual Men in Brazil and Thailand: The Role of ART Adherence and Depressive Symptoms (HPTN 063)

The effect of non-injection substance use on HIV viral load (VL) is understudied in international settings. Data are from HPTN063, a longitudinal observational study of HIV-infected individuals in Brazil, Thailand, and Zambia, with focus on men with VL data (Brazil = 146; Thailand = 159). Generalized linear mixed models (GLMM) assessed whether non-injection substance use (stimulants, cannabis, alcohol, polysubstance) was associated with VL undetectability. ART adherence and depressive symptoms were examined as mediators of the association. In Thailand, substance use was not significantly associated with VL undetectability or ART adherence, but alcohol misuse among MSM was associated with increased odds of depression (AOR = 2.75; 95% CI 1.20, 6.32, p = 0.02). In Brazil, alcohol misuse by MSM was associated with decreased odds of undetectable VL (AOR = 0.34; 95% CI 0.13, 0.92, p = 0.03). Polysubstance use by heterosexual men in Brazil was associated with decreased odds of ART adherence (AOR = 0.25; 95% CI 0.08, 0.78, p = 0.02). VL suppression appears attainable among non-injection substance users. Substance use interventions among HIV-positive men should address depression, adherence, and VL undetectability.

Active cocaine use is associated with lack of HIV-1 virologic suppression independent of nonadherence to antiretroviral therapy: use of a rapid screening tool during routine clinic visits

Clarifying the relationship between illicit drug use and HIV-1 virologic suppression requires characterization of both illicit drug use activity and adherence to antiretroviral therapy (ART). We developed a rapid clinical questionnaire to assess prior 7-day illicit drug use and ART adherence in a cross-sectional study among 1777 HIV-infected persons in care. Of these, 76% were male, 35% were African-American, and 8% reported injection drug use as their probable route of HIV-1 infection. Questionnaire-reported frequencies of cocaine and marijuana use within the previous 7 days were 3.3% and 12.1%, respectively. Over three quarters (77.8%) of participants were on ART, of whom 69.7% had HIV-1 virologic suppression (HIV-1 RNA<48 copies/mL). Univariate analyses revealed that compared to no use, cocaine and marijuana use were both associated with missed ART doses (P<0.01). Multivariable logistic regression analysis adjusting for nonadherence demonstrated that cocaine use was independently associated with failing to achieve virologic suppression (adjusted odds ratio (aOR): 0.46; 95% confidence interval (95% CI): 0.22-0.98) but marijuana use was not (aOR: 1.08; 95% CI: 0.72-1.62). This result strengthens the evidence of a direct effect of cocaine on virologic control, independent of nonadherence to ART.

Associations between use of crack cocaine and HIV-1 disease progression: research findings and implications for mother-to-infant transmission

Recent in vitro and in vivo research has suggested that cocaine has a direct effect on the pathogenesis of AIDS. These findings are confirmed by epidemiological studies linking the use of injected, inhaled, and smoked (crack) cocaine and indicators of HIV disease progression, even among adherent users of highly active antiretroviral therapy. Recent studies of vertical HIV transmission suggest that cocaine use may play a role in mother-to-child infection via alteration of maternal immune responses, enhanced viral replication in maternal immune cells, or alterations in the immune systems of neonates or infants. The purpose of this article is to review research conducted over the past several decades on associations between use of cocaine and HIV disease progression, especially among HIV+ women, and to explore its potential relevance for understanding mother-to-infant transmission of HIV.

A pilot study of community-friendly manual-guided drug counseling

Therapist training manuals that are more "community friendly" are needed to facilitate effectiveness testing and dissemination of treatments to community based setting. The aim of the current project was to create revised versions of individual drug counseling (IDC) and group drug counseling (GDC) treatment manuals for cocaine dependence and to conduct a preliminary study of their effectiveness. After changing the format and context of existing drug counseling manuals to have greater ease of use in the community, draft manuals were given to 23 community-based counselors for their feedback. Final versions were then used in a pilot randomized clinical trial involving 41 cocaine-dependent patients who received 3 months of either IDC + GDC or GDC-alone treatment. Counselors implemented the new treatment manuals with acceptable levels of adherence and competence. Outcome results indicated that substantial change in drug use was evident, but the amount of abstinence obtained was limited.

Chronic morphine exposure causes pronounced virus replication in cerebral compartment and accelerated onset of AIDS in SIV/SHIV-infected Indian rhesus macaques

Six morphine-exposed and 3 control male Indian rhesus macaques were intravenously inoculated with mixture of SHIV(KU), SHIV(89.6)P and SIV/17E-Fr. These animals were followed for a period of 56 weeks in order to determine CD4 and CD8 profile, viral loads in plasma and cerebrospinal fluid (CSF), relative distribution of 3 pathogenic viruses in blood and brain, binding as well neutralizing antibody levels and cellular immune responses. Both morphine-exposed and control macaques showed a precipitous loss of CD4+ T cells; control animals, however, showed a greater tendency to recover these cells than did their morphine-exposed counterparts. The plasma and CSF viral loads were significantly higher in morphine-exposed group than those in the control group. Four morphine-exposed animals succumbed to SIV/SHIV-induced AIDS at week 18, 19, 20 and 51; post-infection with neurological disorders was found in 3 of the 4 animals. At the end of the 56-week observation period, 2 morphine-exposed and 3 control animals were still alive. All 3 viruses replicated in the blood of both morphine-exposed and control macaques, but the cerebral compartment showed a selection phenomenon; only SIV/17E-Fr and SHIV(KU) successfully crossed the blood brain barrier (BBB). The morphine-exposed macaques further favored viral migration through the blood brain barrier (BBB). SIV/17E-Fr crossed the BBB within 2 weeks in both morphine-exposed and control macaques, whereas SHIV(KU) crossed the BBB more rapidly in morphine-exposed than in control macaques. Three morphine-exposed macaques (euthanized at weeks 18, 19 and 20) did not develop cellular or humoral immune responses, whereas the other 3 morphine-exposed and 3 control macaques developed both cellular and humoral immune responses.

Drug use and risk of HIV/AIDS on the Mexico-USA border: a comparison of treatment admissions in both countries

This study analyzes trends in treatment admissions and summarizes HIV/AIDS risk factors along the US-Mexican border. Data are presented at the national level and at the state level for states along the border. Client data also are compared for treatment programs located in sister cities on the Texas-Mexico border. These data show that methamphetamine admissions are increasing nationally and methamphetamine use is a major problem in the western states on both sides of the border. Use of Ice (smoked methamphetamine) has increased significantly. Use of crack (smoked cocaine) is a growing problem on the border, and injection is the primary route for using black tar heroin in this area. Each of these drugs is a risk factor, either from drug-influenced risky sexual behaviors or from sharing injection equipment. In addition, the availability of drugs on the border and patterns of risky behaviors among migrants mean that drug users on the border are at risk of HIV/AIDS, and this risk is expected to increase with the spreading methamphetamine epidemic and smoking of crack cocaine. Comparable data on HIV/AIDS are needed for further studies of the relationship of drug use and HIV/AIDS on the border.

The role of substance abuse in HIV disease progression: reconciling differences from laboratory and epidemiologic investigations

From the onset of the HIV/AIDS epidemic, the use of licit and illicit drugs has been investigated for its potential impact on HIV disease progression. Findings from a large number of laboratory-based studies indicate that drug abuse may exacerbate HIV disease progression; however, epidemiological studies have shown mixed results. This article presents a review of findings from both laboratory-based and epidemiologic investigations. In addition, we provide a careful evaluation of methodological strengths and limitations inherent to both study designs in order to provide a more nuanced understanding of how these findings may complement one another.

The relationship between non-injection drug use behaviors on progression to AIDS and death in a cohort of HIV seropositive women in the era of highly active antiretroviral therapy use

AIMS

To evaluate the effects of longitudinal patterns and types of non-injection drug use (NIDU) on HIV progression in the highly active antiretroviral therapy (HAART) era.

DESIGN

Women's Interagency HIV Study (WIHS), a prospective cohort study conducted at six US sites.

METHODS

Data were collected semi-annually from 1994 to 2002 on 1046 HIV(+) women. Multivariate Cox proportional hazards modeling was used to estimate relative hazards for developing AIDS and for death by pattern and type of NIDU.

FINDINGS

During follow-up, 285 AIDS events and 287 deaths, of which 177 were AIDS-related, were reported. At baseline, consistent and former NIDU was associated with CD4(+) counts of < 200 cells/microl (43% and 46%, respectively) and viral load > 40,000 copies/ml (53% and 55%, respectively). Consistent NIDU reported less HAART use (53%) compared with other NIDU patterns. Stimulant use was associated with CD4(+) cell counts of < 200 cells/microl (53%) and lower HAART initiation (63%) compared with other NIDU types. In multivariate analyses, progression to AIDS was significantly higher among consistent (RH = 2.52), inconsistent (RH = 1.63) and former (RH = 1.56) users compared with never users; and for stimulant (RH = 2.04) and polydrug (RH = 1.65) users compared with non-users. Progression to all-cause death was higher only among former users (RH = 1.48) compared with never users in multivariate analysis. NIDU behaviors were not associated with progression to AIDS-related death.

CONCLUSIONS

In this study, pattern and type of NIDU were associated with HIV progression to AIDS and all-cause mortality. These differences were associated with lower HAART utilization among consistent NIDU and use of stimulants, and poor baseline immunological and virological status among former users.