Rectal Lubricant Use & Incident STIs at 9 US STD Clinics 1 UCLA Fielding School of Public Health, 2 UCLA David Geffen School of Medicine, 3 Dept. of Epidemiology & Public Health, Miller School of Medicine, University of Miami, 4 Division of Infectious Diseases, University of Miami, 5 Los Angeles Gay and Lesbian Center, 6 Whitman- Walker Health, Washington, DC, 7 Department of Psychiatry, University of Pittsburgh School of Medicine, 8 University of Washington Center for AIDS & STDs, 9 Mailman School of Public Health, Columbia University IRMA WEBINAR: June 5, 2014 Pamina M. Gorbach 1,2, Heather A. Pines 1, Daniel J. Feaster 3, Marjan Javanbakht 1, Zoilyn Gomez 3, Jose Castro 4, Robert Bolan 5, Sarah Henn 6, Antoine Douaihy 7, Matthew Golden 8, and Lisa Metsch 3,9

Introduction Lubricant (lube) used during receptive anal intercourse (RAI) may affect the acquisition of rectal sexually transmitted infections (rSTIs/syphilis) 1 We assessed the association between lube use during RAI and the acquisition of rSTIs/syphilis among HIV-negative men who have sex with men (MSM) attending STD clinics in the United States.

Methods Data were collected as part of Project AWARE, a randomized controlled trial of HIV testing and counseling conducted at 9 US STD clinics At the 6 month visit in 2010, 951 MSM completed a web-based survey on lube use in addition to the behavioral risk ACASI and were tested for rectal chlamydia, rectal gonorrhea, and syphilis (rSTIs/syphilis) Multivariable logistic regression was used to examine the association between the rSTIs/syphilis at that the 6 month visit and: The frequency of lubricant use during RAI (past month) The types of lubricant used most often during RAI (past month)

Results Of the MSM enrolled in Project AWARE who completed their 6 month visit (N=951), 572 (60%) were HIV-negative and reported having receptive anal intercourse (RAI) in the past month Of these men 12.6% (n=72) were diagnosed with rSTI/syphilis at their 6 month visit In the past 6 months, men reported a mean of 6.2 (SD=13.3) anal intercourse (AI) partners, and 2.6 (SD=9.9) partners with whom condoms were not used during AI In the prior month, men reported using lube during a mean of 82% of RAI acts (median 100%) and condoms during a mean of 54% of RAI acts (median 67%)

Characteristics of HIV-negative MSM enrolled in Project AWARE who reported RAI during the past month by rectal STIs/syphilis diagnosis at the 6 month visit (N=572). No Rectal STIs (n=500) Rectal STI/Syphilis (n=72) Age group (years)**N%N% ≥ > High school education*** Unemployed* Ecstasy (past 6 months) ** Crack cocaine* Mean age (years) (SD)**

Top 10 lubes reported by HIV-negative MSM enrolled in Project AWARE who reported RAI during the past month “Which one of these lubricants did you use MOST often in the past month during receptive anal sex” (N=454)?

Factors associated with rectal STIs/syphilis diagnosis among HIV-negative MSM at the 6 month visit in Project AWARE > High school education (AOR 0.46, 95% CI 0.23, 0.91) Number of male AI partners last 6 months (AOR 1.01, 95% CI 1.00, 1.03) An interaction of age by lube use during RAI (always in past month) – lube use not a risk factor (protective) at younger age groups but in older age groups it IS a risk…examples below… 20 years (AOR 0.32, 95% CI 0.13, 0.81) 35 years (AOR 8.94, 95% CI 1.06, 75.83) 40 years (AOR 27.03, 95% CI 1.40, ) Models controlled for site, substance use, number of RAI acts with condom use, HSV2 at baseline

Association between lube type used most often during RAI in the past month rectal STIs/syphilis diagnosis at the 6 month visit: HIV-negative MSM in Project AWARE

Discussion This is our second study to show an association between rectal STIs/syphilis and lubricant use for men who have sex with men By collecting more detailed data on lubricant use, focusing only on HIV-negative men, and embedding our study in a larger prospective study, these results move our understanding of lubricant use and its relationship with rSTIs forward by identifying a type of lubricant that is associated with incident rSTs and a variable pattern by age

Discussion – Silicone? Other behaviors confounding the relationship between the use of silicone-based lubricants and rectal STIs/syphilis? There were significantly more men who used silicone-based lubricants most often among those reporting use of some “party drugs” like GHB, poppers, powdered cocaine, tranquilizers/barbiturates, prescription drugs and Viagra Multivariable models did not show a significant association between substance use and rSTIs/syphilis, but trending in the positive direction and may have been significant with greater power Could not test for an interaction between substance use and age Silicone-based lubricants are known to having a longer duration of activity than other types of lubricant, which could allow for longer duration and/or repeated sexual events while under the influence of substances Silicone-based lubricants may adhere more to the rectal tissue…possible unmeasured effects that may also enhance infectivity of rSTIs? Silicone used more frequently by those reporting most frequent condom use.

Discussion The association we observe with age and lubricant use may be explained by two factors 1)Lubricant use may have a cumulative effect on the rectal epithelium, such that it may take many applications and years of use to result in enhanced risk for rSTIs 2)Older men may have a thinner rectal epithelial cellular lining, which may be more vulnerable and pliable than that of younger men, resulting in different lubricant absorption rates or enhanced sloughing of rectal epithelial during RAI These are just conjectures…future relationship is needed…