A Bidirectional Relationship between Smoking and HIV in the Era of Antiretroviral Therapy (ART)

Background: The potential effect of smoking on HIV and response to antiretroviral therapy has been explored. Yet, the interactions between smoking and HIV, particularly, the impact of antiretroviral (ARTs) to variability in biochemical markers of cigarette smoking is currently unknown. Methods: A longitudinal study was conducted to determine interactions between smoking and HIV, the impact of antiretroviral, and the variability in the biochemical markers of cigarette smoke exposure. Four hundred and twenty people living with HIV (PLWH) were recruited into 4 equal groups based on HIV and smoking status. Findings: Half of the participants were smokers. Analyses confirmed that smokers had higher viral loads compared to non-smokers. Unsurprisingly, cotinine levels between ART and non-ART recipients tended to differ (233 ± 22 vs. non-ART=200 ± 36 ng/ml, p=0.09). Females with irregular menstrual cycles exhibited higher cotinine levels (410 ± 85 vs. 202 ± 32 ng/ml, p=0.02). Multivariate analyses confirmed that ARTs, females with irregular cycles, and number of packs predict cotinine levels. Conclusion: To our knowledge, this is the first study to identify a plausible interaction between HIV medication and nicotine metabolism. However, findings agree with the concept that both are metabolized by the CYP1A2 and CYP3A4 enzyme system.