Impact of Behavioral Drug Abuse Treatment on Sexual Risk Behaviors: An Integrative Data Analysis of Eight Trials Conducted Within the National Drug Abuse Treatment Clinical Trials Network

External validity of analogue sexual risk laboratory data

This article presents data on the external validity of an alcohol administration study of sexual decision-making in men who have sex with men (MSM) ages 21-50. Men (N = 135) randomized to alcohol (blood alcohol concentration [BAC] = .075%) or water control conditions reported intentions to engage in condomless anal intercourse (CAI) in response to video vignettes. Following the experiment participants provided 6 weeks of experience sampling method (ESM) data assessing intoxication, sexual arousal, partner relationship, and sexual behavior. Laboratory CAI intentions were hypothesized to predict future CAI behavior, and associations were hypothesized to be conditional upon sexual arousal and intoxication contextual factors as well as laboratory beverage condition. The hypotheses were partially supported. CAI intentions were correlated with subject proportions of days engaging in CAI (r = .29). A multilevel analysis indicated, on average, CAI intention predicted increased probability of CAI versus anal intercourse with a condom (relative risk ratio [RRR] = 1.43). There was mixed evidence of CAI intentions effects being conditional upon laboratory condition as well as arousal and intoxication contextual factors. Graphs of conditional marginal effects identified regions of significance. Effects of CAI intention for men in the alcohol condition on the CAI versus No Sex contrast were significant when sexual arousal was elevated. CAI intentions for men in the water control condition predicted a higher probability of CAI versus anal intercourse with a condom when intoxication was moderately elevated and/or arousal moderately low. The results support the external validity of alcohol administration experiments of sexual decision-making among MSM and, reciprocally, provide support for the validity of ESM assessment of sexual behavior. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Effect of alcohol exposure on the efficacy and safety of tenofovir alafenamide fumarate, a major medicine against human immunodeficiency virus

Human immunodeficiency virus (HIV) continues to be a major health concern. AIDS-related deaths (acquired immunodeficiency syndrome) have decreased recently, but chronic liver disease is now a major cause of mortality among HIV patients. Widespread alcohol use is recognized to be a major contributing factor. Tenofovir alafenamide fumarate (TAF), one of the most used HIV drugs, requires hydrolysis followed by phosphorylation to produce tenofovir diphosphate, the ultimate anti-HIV metabolite. Carboxylesterase-1 (CES1), established to hydrolyze TAF, is known to catalyze transesterification in the presence of ethanol. The aim of the study was to test the hypothesis that metabolism-based interactions between TAF and ethanol negatively impact both efficacy and safety of TAF. To test this hypothesis, the metabolism of TAF was determined in human primary hepatocytes and with a large number of human liver samples (S9 fractions) in the presence or absence of ethanol. The metabolism was monitored by LC-MS/MS (liquid chromatography with tandem mass spectrometry) and the level of CES1 or CES2 was determined by Western blotting. Consistent with the hypothesis, TAF underwent transesterification in the presence of ethanol accompanied by decreased hydrolysis. The formation of tenofovir diphosphate (the therapeutically active metabolite) was significantly decreased. In addition, TAF but not its hydrolytic metabolite, was found to increase intracellular lipid retention, and the increase was enhanced by ethanol. These findings conclude that alcohol consumption, beyond commonly accepted poor adherence to HIV medications, directly impacts the efficacy and safety of TAF.

An application of agent-based modeling to explore the impact of decreasing incarceration rates and increasing drug treatment access on sero-discordant partnerships among people who inject drugs

BACKGROUND

People who inject drugs (PWID) lag behind other key populations in HIV care continuum outcomes. The impacts of criminal justice reform and increasing drug treatment access on HIV have been underexplored.

METHODS

We developed agent-based models (ABM) of sexual partnerships among PWID and non-PWID, and injection equipment-sharing partnerships among PWID in five US cities (Baltimore, Boston, Miami, New York City, San Francisco) over 3 years. The first set of ABM projected changes in partnership discordance among PWID as a function of decreasing ZIP code-level incarceration rates. The second set projected discordance as a function of increasing ZIP code-level drug treatment access. ABM were parameterized and validated overall, and by city and PWID race/ethnicity (Black, Latino, White) using National HIV Behavioral Surveillance data, administrative ZIP code-level data, surveillance reports and prior literature. Informed by research on prisoner release and community-level HIV prevalence, reductions in incarceration rates were fixed at 5% and 30% and respectively projected to increase ZIP code-level HIV prevalence by 2% and 12%. Increases in drug treatment access were fixed at 30% and 58%.

RESULTS

In each city, a 30% reduction in ZIP code-level incarceration rates and 12% increase in ZIP code-level HIV prevalence significantly increased sero-discordance among at least one racial/ethnic group of PWID by 1-3 percentage points. A 5% reduction in incarceration rates, and 30% and 58% increases in drug treatment access, led to isolated significant changes in sero-discordance among Black and White PWID that were less than 1 percentage point.

CONCLUSION

Reductions in incarceration rates may lead to short-term increases in sero-discordant partnerships among some PWID by increasing community-level HIV prevalence. Efforts to increase HIV testing, engagement in care and community reintegration post release, should be strengthened in the wake of incarceration reform. Additional research should confirm these findings and explore the lack of widespread impacts of drug treatment in this study.