Transcript Rectal Lubricant Use & Incident STIs at 9 US STD Clinics

Rectal Lubricant Use &
Incident STIs
at 9 US STD Clinics
1UCLA
Fielding School of Public Health, 2UCLA David Geffen School of
Medicine, 3Dept. of Epidemiology & Public Health, Miller School of
Medicine, University of Miami, 4Division of Infectious Diseases,
University of Miami, 5Los Angeles Gay and Lesbian Center, 6WhitmanWalker Health, Washington, DC, 7Department of Psychiatry, University
of Pittsburgh School of Medicine, 8University of Washington Center for
AIDS & STDs, 9Mailman School of Public Health, Columbia University
IRMA WEBINAR: June 5, 2014
Pamina M. Gorbach1,2,
Heather A. Pines1 ,
Daniel J. Feaster3,
Marjan Javanbakht1 ,
Zoilyn Gomez3, Jose
Castro4, Robert Bolan5
Sarah Henn6, Antoine
Douaihy7, Matthew
Golden8, and Lisa
Metsch3,9
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)
Age group (years)**
18-24
25-29
30-34
≥ 35
> High school education***
Unemployed*
Ecstasy (past 6 months) **
Crack cocaine*
Mean age (years) (SD)**
N
137
140
83
140
241
148
70
9
31.1
Rectal STI/Syphilis
(n=72)
%
27.4
28.0
16.6
28.0
48.2
29.7
14.0
1.8
9.3
N
33
20
13
6
17
33
20
5
26.7
%
45.8
27.8
18.1
8.3
23.6
45.8
27.8
6.9
6.6
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, 521.79)
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?
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…