1. B. R. Simon Rosser, PhD, MPH & Syed Noor, PhD
Enema use among men who have sex with men: A behavioral epidemiologic study with implications for HIV prevention
B. R. Simon Rosser, PhD, MPH & Syed Noor, PhD
HIV/STI Intervention & Prevention Studies (HIPS) Program
Division of Epidemiology & Community Health
School of Public Health
University of Minnesota
21st World Congress on Sexual Health
Porto Allegre, Sept 21-24, 2013

2. Introduction Very little is known about enema use among MSM.
Studies have found it associated with both STI and HIV acquisition -possibly due to damaging the anal epithelium.
Research on microbicides for MSM make studying enema use particularly relevant.

3. Enema Use = Rectal Douching
Variety of commercial and home products
Saline, H2O, and
home mixes (e.g., soap)

4. Enema Use = Rectal Douching
Variety of practices in inserting the enema to flush the rectum before and/or after sex
But we lack empirical data of what and how enemas are being used for anal sex in MSM.

5. Methods
As part of a wider study, we conducted a sub-study on enema use. Participants: 4,992 MSM in 16 US cities, recruited from two large gay websites Typical online MSM sample: young, white (non Hispanic), well-educated, urban, liberal, in a relationship (53%), and HIV- (89%) Procedures: Online surveys in 2011.

6. Selected Key Results (N=4992 U.S. MSM)
Ever: Frequency of behavior: 52% MSM Current: 35% reported douching (88% before receptive anal sex and 28% after receptive anal sex)

7. Selected Key Results (N=4992 U.S. MSM)
Ever: Frequency of behavior: 52% MSM Current: 35% reported douching (88% before receptive anal sex and 28% after receptive anal sex)

8. Selected Key Results
When do you douche before sex? (N=2,221 douche before MSM)
13% mainly before unprotected RAI
70% before any RAI
17% only before protected RAI
When do you douche after sex? (N=704 douche after MSM)
40% mainly after unprotected RAI
49% after any RAI
10% mainly after protected anal sex
=> Douching appears to be used as an HIV prevention strategy

9. Key Results Type of products used: When? Most (66%) douche with water
24% add salt, soap or bacterial products
30% use commercially available products
Race/ethnicity differences found on products used
When?
Before sex: Mean 60 minutes (IQR: min)
After sex: Mean 30 min (IQR: min)

10. Why do MSM douche? (N=2,597 US MSM “douchers” online surveys, 2011)
Reason given for douching before sex %
Sex preparation 9
Hygiene/Cleanliness (to avoid feces) 64
Partner considerations 4
To clean out anything which might be transmissible 2
To avoid embarrassment 16
To get excited for anal sex 1
To flush out any left over ejaculate
To increase pleasure 3
Other reasons
Reason for douching after sex
55%
Transition from sex
28%
HIV/STI prevention
13%
Other 5%

11. Reasons given for NOT douching (N=4,301 US MSM online surveys, 2011)
We also asked MSM who don’t douche, why they don’t:
Reason for NOT douching before sex %
Don’t engage in anal sex 20
Don’t like it, find it painful or uncomfortable 6
I prefer sex to be spontaneous 46
I do not mind/prefer anal sex being “dirty”/”natural” 10
HIV/STI prevention 4
I don’t know about douching 27
Other

12. Multiple logistic regression models
Who is more likely to douche and when?
Person variables:
Higher income (p<.005)
Being a man of color (p<.005)
Being HIV positive (p<.001)
Being diagnosed with an STI, last 12 months (p<.01)
Behavioral variables:
Meeting partners online and offline (p<.001)
Being “versatile” (p<.001) or a “bottom” (p<.001)
Having 2+ unprotected anal sex partners (p<.001)
were each associated with recent enema use after adjusting for other variables.

13. Discussion
Significance: To the best of our review, this is the first large study of enema use among MSM to be conducted.

14. Key Conclusions
1-in-3 MSM douche regularly – this behavior is very common
Douching appears closely associated with HIV risk behavior, HIV+ status and STI diagnosis.
HIV+ MSM and STI+ MSM were more likely to report adding soap or antibacterial product to water before douching. Since lab studies have shown that water (and soap) damage the epithelium, this is potentially problematic.

15. Key conclusions 13% use enemas post-coitus for HIV prevention
27% non-users state they do not know about enemas
Need for education

16. Future Research Recommendations
Douching with water or water and soap may be a particular concern if it increases damage to the epithelium.
Development of a non-damaging, non-water based enema specifically for use before anal sex is recommended.

17. Implications for HIV prevention education
Risk elimination (“just say no”) – unlikely to be successful
Risk reduction (education on safer enema use) – needs science to identify the least toxic or non-toxic substance (e.g., iso-osmolar based enemas)
Caution: advocating for water based lubricant but warning about water based enemas appears contradictory

18. Limitations
Cross sectional study so causality and temporality cannot be assumed
Socially-sensitive topic where all data are self-report; rates are likely under-estimates
Sample is a large convenience sample not a representative one – generalizability of findings are not known.

19. Acknowledgements The SILAS grant is funded by NIAAA (AA01627001).
These results are in press: Noor, S.W., Rosser, B.R.S. (2014). Enema use among men who have sex with men: A behavioral epidemiologic study with implications for HIV/STI prevention. Archives of Sexual Behavior, in press.
The SILAS grant is funded by NIAAA (AA ).
(PI: Rosser).
Investigators, Staff and Consultants:
B. R. Simon Rosser, PhD
Sonya S. Brady, PhD
Michael Oakes, PhD
Rhonda Jones-Webb, PhD
Keith Horvath, PhD
Gunna Kilian, BA
Syed W. Noor, PhD
Joe Konstan, PhD
Derek Smolenski, PhD, MPH
Dale Carpenter, JD
Richard Weinmeyer, Mphil
Katherine Nygaard, MPH
J. Michael Wilkerson, PhD, MPH

20. B. R. Simon Rosser, PhD, MPH, LP rosser@umn.edu
Thank you and wishing
you good sexual health!
B. R. Simon Rosser, PhD, MPH, LP