Direct and Indirect Effects of Heavy Alcohol Use on Clinical Outcomes in a Longitudinal Study of HIV Patients on ART
In a cohort of patients receiving care for HIV, we examined longitudinally the impact of past 30-day frequency of heavy drinking (consuming 5+ drinks on one occasion) on HIV-related (detectable viral load and CD4+ T cell count) and non-HIV-related (hemoglobin and biomarkers of kidney function and liver fibrosis) clinical outcomes and the extent to which these effects were due to reduced antiretroviral therapy (ART) adherence. Data came from the Study to Understand the Natural History of HIV/AIDS in the Era of Effective Therapy. Between March 2004 and June 2006, 533 individuals receiving ART were recruited and followed every 6 months for six years. Using longitudinal mediation analysis, we estimated natural direct effects (NDE) of heavy drinking frequency (never, 1–3 times, or 4+ times in the past 30 days) on clinical outcomes and natural indirect effects (NIE) mediated via ART adherence. A one-level increase in heavy drinking frequency had a significant negative NDE on CD4+ T-cell counts (-10.61 cells/mm3; 95 % CI [-17.10, -4.12]) and a significant NIE through reduced ART adherence of -0.72 cells/mm3 (95 % CI [-1.28, -0.15]), as well as a significant NIE on risk of detectable viral load (risk ratio = 1.03; 95 % CI [1.00, 1.05]). Heavy drinking had a significant detrimental NIE on a combined index of 5-year mortality risk and detrimental NDE and total effect on a biomarker of liver fibrosis. Heavy drinking has deleterious effects on multiple clinical outcomes in people living with HIV, some of which are mediated through reduced ART adherence.
KeywordsAlcohol HIV Adherence Viral load Liver function VACS Index
This work was supported by the Centers for Disease Control and Prevention contract numbers 200-2002-00,610, 200-2002-00611, 200-2002-00612, 200-2002-00613, 200-2007-23633, 200-2007-23634, 200-2007-23635, and 200-2007-23636. Additional support was provided by grant number P01 AA019072 from the National Institute on Alcohol Abuse and Alcoholism, grant number T32 DA016184 from the National Institute on Drug Abuse, and the Lifespan/Tufts/Brown Center for AIDS Research (CFAR) grant number P30 AI042853.
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflicts of interest.
The findings and conclusions from this review are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
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