Associations of Sex Work Modality Classifications with Condom and Substance Use Behaviors Among Women Who Exchange...

Women who exchange sex for drugs or money (WES) are disproportionately affected by HIV, particularly in the United States. We used latent class analysis to identify distinct groups, or classes, of sex work modalities (ways in which women find their exchange sex partners) and assess differences between class membership and behaviors associated with HIV transmission. Data are from the 2016 National HIV Behavioral Surveillance (NHBS) cycle focused on heterosexuals at increased risk for HIV infection (HET). Four cities participated in a pilot study exploring a subset of WES. All participants (n = 1,392) were recruited using respondent-driven sampling (RDS). We identified four distinct classes of sex work modalities and calculated posterior class probabilities for the four-class model. Based on the distinct patterns observed between classes, we labeled class 1 "drug network," class 2 "social ties," class 3 "online and escort services," and class 4 "unstructured sex work"; 26.5% of women were in the drug network class, 15.2% in the social ties class, 5.1% in the online and escort services class, and 53.2% in the unstructured sex work class. Women in the drug network class reported higher odds of engaging in substance use and condomless sex behaviors compared to women in other classes of sex work modalities. Findings suggest there are differential risk profiles associated with sex work modality membership. Ways in which women find their exchange sex partners (i.e. sex work modalities) should be considered when designing prevention programs tailored to women at increased risk for HIV infection.