Abstract
In recent years, increasing attention and research has been placed on how to better engage people living with HIV/AIDS (PLHIV) in the HIV care continuum, as treatment for HIV/AIDS is now extremely effective. However, several marginalized populations continue to be disproportionately affected by the virus, hampering efforts to end the epidemic. Substance users remain one of the most difficult groups to engage and retain in HIV care and often have unsuppressed poorly controlled HIV infection as a result of inadequate antiretroviral (ART) adherence. Research shows substance users are also more likely to have multiple co-occurring social syndemics and engage in risky behaviors, putting them at increased risk for coinfection, faster disease progression, and onward HIV transmission. Consistent evidence indicates that economic disparity is a driving force of the HIV epidemic in the US and is limiting success at each step of the care continuum. Food insecurity is an extreme form of social and economic disparity, linking various social and structural constructs, and has been shown in the literature to affect multiple health and HIV-related outcomes. Of growing interest is whether food insecurity independently predicts HIV medication adherence, and how this relationship may look and change over time. This dissertation introduces three novel methods to analyze the potentially causal relationship between food insecurity and HIV medication adherence longitudinally in a sample of hospitalized PLHIV who use substances. Specifically, Aim/Paper #1 used machine learning to identify important predictors of food insecurity, which informed propensity score weighting in Aim/Paper #2, which analyzed the relationship of interest using a marginal structural model to establish potential causality. In Aim/Paper #3, the concurrent and reciprocal relationships between food insecurity and HIV medication adherence were analyzed over time using a cross-lagged panel model to examine reciprocal patterns of influence. Ultimately, this dissertation hopes to contribute to the growing evidence that addressing PLHIV’s food security needs may be an integral and innovative approach to improving engagement and retention in the HIV care continuum in an effort to ending the HIV epidemic.