CROI 2015 Program and Abstracts

Abstract Listing

Poster Abstracts

1030 CanWe Trust Self-Reported CondomUse? Association Between Reporting Bias and STIs Hongjie Liu University of Maryland, College Park, College Park, MD, US

Background: Self-reported condom use has been used for three decades in behavioral research. However, reporting bias and its association with sexually transmitted infections (STIs) including HIV have seldom assessed in large-scale studies. The objectives of this study were to use a biologic measure to validate self-reported condom use and to investigate if reporting bias was associated with syphilis among older female sex workers (FSWs) in China. Methods: The study was conducted among 1,245 older FSWs who were 35 years old and older in three cities (about 400 per each). Respondent-driving sampling was used to recruited study subjects. Prevalent and active syphilis was tested in blood samples. Prostate-specific antigen (PSA) was tested in vaginal secretion samples. The presence of PSA indicates unprotected sex. If an older FSW reported having had no sex in the past 24 hours and PSA was present, she was classified as having a discordant report on no sex. Similarly, if an older FSW reported having had only protected sex in the past 24 hours, but PSA was present, she was classified as having a discordant report on protected sex. Results: The prevalence of syphilis was 23% (95%CI: 21-26%) and the rate of active syphilis was 10% (95%CI: 9-12%) among older FSWs. Among 493 older FSWs who reported having had no sex in the past 24 hours, 135 were tested positive for PSA, resulting the proportion of discordant report in no sex was 27%. Among 445 older FSWs who reported having used condoms for every sexual intercourse, 166 were tested positive for PSA, i.e., the proportion of discordant report in protected sex was 37%. After controlling for confounding variables, older FSWs who had prevalent syphilis were more likely to have discordant report in no sex [prevalence ratio (PR) = 1.77; 95%CI, 1.29-2.42)] and in protected sex (PR =1.56; 95%CI, 1.14-2.14) than those who did not have prevalent syphilis. Similarly, older FSWs who had active syphilis were more likely to have discordant report in no sex (PR =1.94; 95%CI, 1.37-2.74) and in protected sex (PR =1.65; 95%CI, 1.12-2.43) than those who did not have active syphilis. Similar results were presented in separated analyses across the three study sites.

Conclusions: Self-reported condom use has strong reporting bias and may not be used as an outcome to measure effectiveness of STI interventions as the bias is also associated with occurrence of STIs. PSA test provides a valid bio-approach for assessing actual condom use and can be used in large scale studies. 1031 Prevalence and Correlates of Exchange Sex Among Low-Income Heterosexual Women in 21 US Cities Catlainn Sionean ; Rashunda Lewis; Lina M. Nerlander; Gabriela Paz-Bailey On behalf of the NHBS Study Group US Centers for Disease Control and Prevention (CDC), Atlanta, GA, US Background: Female sex workers and other women who exchange sex for money or drugs are at increased risk for HIV infection in many countries; however, little is known about exchange sex among women in the United States. We used data from the 2010 heterosexual cycle of the National HIV Behavioral Surveillance System (NHBS), a cross-sectional survey conducted in 21 US cities with high AIDS prevalence, to estimate the percentage of female participants who received money or drugs from a man in exchange for sex and compare their HIV-related behaviors with those among women who had not exchanged sex. Methods: Heterosexuals of low socioeconomic status were recruited via respondent-driven sampling, interviewed, and tested for HIV infection. Analyses were limited to female participants with valid interview and HIV test results. We used generalized estimating equations (GEE) to test for associations between exchange sex as the outcome and HIV- related behaviors adjusted for recruitment chain, demographics and network size. We present adjusted prevalence ratios (aPR) and 95% confidence intervals (CI). Results: Among 5507 female participants, 19% had exchanged sex during the past 12 months, among whom the median number of male sex partners during the past 12 months was 6. In multivariable analyses, exchange sex was more common among women who, during the past 12 months: had been homeless (aPR=1.38, 95% CI: 1.24-1.53) vs. not; had been arrested (aPR=1.17, 95% CI: 1.03-1.33) vs. not; used crack cocaine (aPR=1.45, 95% CI: 1.28-1.63) vs not; had been diagnosed with an STD (aPR=1.36, 95% CI: 1.22-1.51) vs. not; had vaginal sex without a condomwith 6 or more partners (aPR=2.07, 95% CI: 1.62-2.65) vs. none; had 2 or more new partners (aPR=2.35 95% CI: 1.98-2.79) vs. none; and women whose last sex partner was at least 10 years older (aPR=1.58, 95% CI: 1.40-1.77) vs. not, was HIV+ or of unknown status (aPR=1.20, 95% CI: 1.07-1.35) vs. negative, had ever been incarcerated (aPR=1.25, 95% CI: 1.11-1.40), or ever had sex with another man (aPR=1.16, 95% CI: 1.04-1.30). Exchange sex was not independently associated with HIV testing, HIV infection, or injection drug use. Conclusions: Among low-income women sampled from select US cities with high rates of poverty and HIV, exchange sex was common overall and particularly among those whose economic circumstances, behaviors, and sex partners indicate increased risk for HIV infection. HIV prevention efforts may be enhanced by outreach to heterosexual women who exchange sex.

Poster Abstracts

605

CROI 2015