1A 1 Factors Associated with Clusters of Risk Behaviors Among Men Who Have Sex with Men (MSM) and Men Who Have Sex with Men and Women (MSMW) with Early Syphilis (ES) in Los Angeles County (LAC), 2010-2012

Tuesday, June 10, 2014: 10:45 AM
Grand Ballroom A/B/C/D1
Ryan Murphy, MPH, PhD and Amy Wohl, MPH, PhD, Division of HIV and STD Programs, Los Angeles County Department of Public Health, Los Angeles, CA

Background:  Identifying geographic and demographic factors associated with clusters of risk behaviors among persons with early syphilis(ES) can guide the development and implementation of targeted interventions within large and diverse communities.

Methods:  4,178 ES cases were reported in Los Angeles County(LAC) in 2010-2012 among MSM/MSMW.  Using latent class analysis(LCA), we identified subgroups within these cases based on responses to dichotomous measures of risk behavior during the past 12 months: anonymous sex, 4 or more sexual partners, substance use(SU), substance use during sex(SUDS) and trading sex for drugs/money.  The probability of a respondent’s membership within a certain risk behavior subgroup was predicted by age, race/ethnicity, MSMW vs. MSM, co-infection with HIV and service planning area(SPA).    

Results:  A five-subgroup model of risk behavior provided the best fit to the data.  Subgroups included: 1)no identified risk, 2) sex with anonymous or many partners without SU, 3)SUDS + many partners + anonymous partners, 4) SUDS + anonymous partners and 5) sex trade.  The prevalence of each subgroup among total ES cases was 33.0%, 48.2%, 10.6%, 6.7% and 1.5%, respectively.  Relative to Whites, African Americans and Latinos were more likely to be classified into the “no identified risk” and “SUDS + anonymous partners” subgroups.  MSMW with ES were more likely than MSM with ES to trade sex for drugs/money.  MSM/MSMW living in South Los Angeles(SPA 6) were more likely than those living in the Metro area(SPA 4) to be in the “no identified risk” group, which consisted of sex with known and fewer partners and sex without substance use.

Conclusions:  The data suggest that a large proportion of minority MSM/MSMW with ES, many of whom reside in SPA 6, acquired the infection through a pattern of behavior that is unlikely to be detected during a routine evaluation of sexual risk.