Finding Sex Partners On-Line: What’s the Risk for STI Finding Sex Partners On-Line: What’s the Risk for STI? Might There be a Benefit? Alia Al-Tayyib, PhD and Cornelis Rietmeijer, MD, PhD Denver Public Health Department Denver, CO

Why all the hype? The Internet has provided a new environment for seeking and meeting sexual partners Soliciting sexual partners on-line is becoming more prevalent, particularly in some groups This behavior has been implicated in increased risk for STI and HIV infection

Current State of Knowledge Previous studies have evaluated Internet sex partners as an outcome Comparisons made between persons seeking sex on the Internet to persons who were not seeking sex on the Internet Focus has been on men who have sex with men (MSM)

What’s the issue? Unclear from existing literature whether seeking sexual partners on the Internet is simply a marker of high risk sexual behavior or whether it actually increases one’s risk taking behaviors resulting in STI/HIV infection

Objective To assess the association between reporting sex with Internet partners and current infection with Chlamydia trachomatis (Ct) and Neisseria gonorrhoeae (GC)

Methods Electronic medical record review of patients attending the Denver Metro Health Clinic August 2006 to September 2007 Retrospective case-control study Analysis limited to patients who were tested for Ct or GC during their clinic visit New diagnosed HIV infection and early syphilis were also considered

Main Measures Case: any patient testing positive for Ct or GC between August 2006 and September 2007 Control: any patient testing negative for Ct or GC during same period Main exposure: self-reported sexual encounters with partners met via the Internet Ever vs. Never Restricted to Ever: past 4 months vs. > 4 months

Other Measures Demographics Sexual behaviors History of STI Race Age Condom use with non-main partner Number of partners past 3 months History of STI History of Ct History of GC Current HIV status

Analysis A-priori decision made to examine data separately by sexual orientation Multivariable modeling using generalized linear models with log link and binomial error distribution Unadjusted odds ratios and 95% CI Adjusted odds ratios and 95% CI A backwards elimination, change-in-estimate strategy was used to assess confounding

Study Flow

Sex with Internet Partners MSM N (%) MSW Women < 4 months 465 (25.2) 173 (2.7) 76 (1.6) 4 – 12 months 158 (8.5) 64 (1.0) 26 (0.6) > 12 months 186 (10.1) 119 (1.8) 52 (1.1) Never 1038 (56.2) 6097 (94.5) 4549 (96.7)

Demographics

Sexual Behaviors

STI History and HIV Status

Association Between Internet Partner and Current Ct/GC Infection MSM (N=1838) OR (95% CI) MSW (N=6180) Women (N=4538) Unadjusted Internet partner Ever Never 0.92 (0.70, 1.20) 1.0 (ref) 0.59 (0.42, 0.81) 0.57 (0.32, 1.01) Adjusted >--------< 0.74 (0.53, 1.03)* 0.66 (0.37, 1.18)* NOTES: *adjusted for race

Association Between Internet Partner and Current Ct/GC Infection MSM (N=809) OR (95% CI) MSW (N=356) Women (N=154) Unadjusted Internet partner Past 4 months > 4 months 1.21 (0.80, 1.85) 1.0 (ref) 0.53 (0.27, 1.02) 1.96 (0.63, 6.15) Adjusted 0.93 (0.60,1.46)* >--------< 1.89 (0.57,6.32)** NOTES: *adjusted for number of partners last 3 months **adjusted for number of partners last 3 months and race

Limitations Cross-sectional chart review of a clinic-based convenience sample All behavioral assessments conducted in the context of routine clinical interview Single question asking whether a person had sex with a person first met on the Internet Do not know the specifics of the Internet sites

Conclusions Sexual encounters with partners met on the Internet may not be as risky as previously thought May actually be protective in some groups

Acknowledgements Internet and STD Center of Excellence Mary MacFarlane Rachel Kachur Clinical staff at DMHC

Thank You