1. Age differences in high pre alence of se al
prevalence sexual
concurrency and concurrent UAI among
US MSM
Eli S Rosenberg, Christine M Khosropour, Patrick S Sullivan
2011 National HIV Prevention Conference
8/15/2011
Department of Epidemiology
Emory University Rollins School of Public Health
Atlanta, GA

2. round [1]: HIV and MSM
V prevalence among MSM is high and MSM continue to bear the
V prevalence among MSM is high and MSM continue to bear the
rden of HIV incidence in the US
ck MSM continue to be overrepresented among new infections
reasing HIV incidence among young MSM is most driven by
i HIV i id MSM i td i b
rease among young black MSM
asons for both racial disparity and increase in incidence among
ung MSM remain unclear
xual network factors such as sexual concurrency have been
ggested as drivers of HIV disparities among MSM
t d di f HIV di iti MSM

3. round [2]: Concurrency, illustrated
person has sex with A, B, C
A
B
C
time
Serial monogamy
other situation:
A
B C
time

4. round [3]: Concurrency: definition
verlapping sexual partnerships where sexual intercourse
th one partner occurs between two acts of intercourse with
th t b t t t fi t ith
other partner.”
Consultation on Concurrent Sexual Partnerships
Consultation on Concurrent Sexual Partnerships
UNAIDS. Nairobi, Kenya, 2009

5. ds [1]:
Checking In: a national web‐based study of
MSM aged ≥ 18 years, having ≥ 1 male sex
MSM aged ≥ 18 years having ≥ 1 male sex
partner in the p12m, and recruited from social
networking websites.
networking websites
Participants completed an online questionnaire
hat included:
• Dyadic behaviors for up to 5 sex partners in the p6m
• A calendar‐based partnership timing module

6. ds [2]: Analysis objectives
What is the period prevalence of sexual
oncurrency in the previous 6 months?
oncurrency in the previous 6 months?
What differences, if any, exist by participant age?

7. s [1]: Participants included in analysis
4,138 answered questions about male sex within the p6m
4,138 answered questions about male sex within the p6m
619 (15%) had no sex in p6m
3,519 (85%) had a sex partner within the p6m
3,519 (85%) had a sex partner within the p6m
989 had 1 sex partner
989 h d 2,530 had > 1 sex partner
2 30 h d
15,782 partner triads for
p
concurrency calculations
MSM included in analysis:
ce/ethnicity: 53% white, 17% black, 14% Hispanic
edian age:
edian age: 27 years (IQR: 22 –
27 years (IQR: 22 – 38)
lf‐reported HIV status: 68% HIV‐, 10% HIV+, 22% untested/unknown

8. s [1a]: Concurrency is a triadic‐level phenomenon
An individual with partners yields
3 potentially concurrent triads.
3 potentially concurrent triads

9. s [2]: Concurrency, by age group
with any concurrent partnerships, p6m
Age: 18 – 19
18 20
20– 24 25
25 – 29 30
30 – 39 40
40 – 49 50 +
50 +
(n = 310) (n = 861) (n = 545) (n = 585) (n = 471) (n = 236)
n 34 % 41 % 43 % 46 % 52 % 47 %
(n = 218) (n = 630) (n = 378) (n = 427) (n = 347) (n = 179)
with >1
49 % 57 % 61 % 62 % 70 % 62 %
ers
lder men significantly more likely than younger men to
g y y y g
ave concurrent partners (both trend p < .0001)

10. s [3]: Biological relevance: concurrent UAI, by age group
with any concurrent UAI triad, p6m (UAI with both partners)
Age: 18 – 19 20– 24 25 – 29 30 – 39 40 – 49 50 +
(n = 252) (n = 691) (n = 458) (n = 474) (n = 376) (n = 196)
n 16 % 13 % 14 % 17 % 21 % 18 %
(n = 171) (n = 475) (n = 301) (n = 331) (n = 262) (n = 140)
with >1
23 % 19 % 20 % 25 % 31 % 26 %
ers
h levels of concurrent UAI, with modest but significant
erences by age (p = 0.007, 0.008)
erences by age (p = 0 007 0 008)

11. s [4]: Triadic findings: concurrency and concurrent UAI, by age group
urrency and UAI among triads of MSM with > 1 partner
Age: 18 – 19 20– 24 25 – 29 30 – 39 40 – 49 50 +
(n = 1,533) (n = 4,216) (n = 2,715) (n =3,404) (n = 2,633) (n = 1,281) adj. p
ent triad 29% 30% 32% 36% 39% 38% 0.0002
6m among:
rent triads 38% 27% 28% 26% 36% 37% p
ncurrent triads
ncurrent triads 18% 17% 16% 19% 24% 21% interaction
Prevalence OR 2.8 1.8 1.9 1.5 1.8 2.3 0.10
ociation between concurrency and UAI
viously undocumented compound risk
valent by age group
sociation between concurrency and UAI, across all ages
OR [95% CI]
alence OR 1.9 [1.7, 2.1]

12. usions:
SM reported a high prevalence of concurrency , particularly
p g p y,p y
ong those ≥ 30 years old
• May be attributable to different norms on monogamy
SM also reported a high prevalence of concurrent UAI
sociation between triadic concurrency and UAI suggests
nt risk that requires further characterization
omparing MSM to heterosexuals in the US :
At least 4x more concurrency among MSM
+ the greater transmission efficiency of UAI
= more expected transmission among MSM, despite
more expected transmission among MSM despite

13. ance:
ontributions
First estimates of concurrency from a large, national study of MSM and
of concurrent UAI at individual and triadic levels
While prevalence is high, concurrency may be modifiable, potentially
While prevalence is high concurrency may be modifiable potentially
making it a high‐impact target in the MSM epidemic.
mitations
Individual‐level analyses allow measurement of the extent of
concurrency and associated factors, but cannot be directly related to
concurrency and associated factors but cannot be directly related to
incidence

14. Thanks!!
se stop by our other Checking In presentations:
cruitment and Retention of Racial/Ethnic Minorities in an Online HIV
ehavioral Risk Study of MSM
ehavioral Risk Study of MSM
Christine Khosropour ‐ Vancouver/Montreal @ 3:30
‐home HIV testing of MSM Enrolled in an Online HIV Behavioral Risk Study
h HIV t ti f MSM E ll d i O li HIV B h i l Ri k St d
Christine Khosropour ‐ Vancouver/Montreal @ 3:30
What Extent is Serosorting Intentional among MSM in the United States?
Erin Kaufman – Poster #054M, Monday
work supported by NIH grants:
R01HD067111 RC1MD004370
RC1MD004370