Abstract for: Using system dynamics to apply syndemic theory to women with and at-risk for HIV

Women in the United States are increasingly affected by HIV/AIDS, most commonly through heterosexual contact. Together childhood sexual abuse, emotional distress, substance use, violence, and financial hardship have been hypothesized to represent a syndemic: a set of mutually reinforcing health and social problems that interact and impose an increased burden on vulnerable populations. To date, models of HIV-related syndemics have predominantly assessed the linear or ‘additive’ relationships between syndemic constructs and outcomes (e.g., HIV-related high risk behaviors). We applied system dynamics modeling to assess the simultaneous interdependencies and feedback processes among these constructs. Our model was informed by applicable research literature, qualitative input from members of the Bronx Community Research Review Board, and previously collected cohort data describing women with a history of HIV-related high-risk behaviors (n=620). The final model demonstrates the causal influence of violent events and substance use on self-worth, emotional distress, and HIV-related high-risk sexual behaviors. Model output displays behavior of these constructs over a simulation period of 104 weeks (2 years), illustrating hypothetical clinically relevant profiles of women with and at-risk for HIV in the Bronx. Overall, the modeling fostered a critical understanding about patterns of interdependency among the syndemic variables unforeseen by general linear modeling.