Risk behaviours by type of concurrency among young people in three STI clinics in the United States.
BACKGROUND
Concurrent sexual partnerships can increase sexually transmissible infections (STI) transmission on a population level. However, different concurrency types may be associated with differential risks for transmission. To investigate this, we describe the prevalence and correlates of four specific concurrency types.


METHODS
Between 2001 and 2004, 1098 young adults attending three STI clinics were interviewed and tested for STIs. Characteristics associated with concurrency types were identified using logistic regression.


RESULTS
Approximately one-third of respondents reported reactive (34%), transitional (36%), compensatory (32%) and experimental (26%) concurrency. Among men, reactive concurrency was associated with not identifying as heterosexual, drug use and having sex the same day as meeting a partner. Among women, reactive concurrency was associated with African-American race and having >3 lifetime partners. Transitional concurrency was associated with >3 lifetime partners for men and women. Among men, compensatory concurrency was associated with African-American race; among women, there were no associations with compensatory concurrency. Among men, experimental concurrency was associated with >3 lifetime partners and having sex the same day as meeting a partner. Among women, experimental concurrency was associated with not identifying as heterosexual, drug use and having sex the same day as meeting a partner.


CONCLUSIONS
All concurrency types were common in this population and each was associated with a set of demographic and risk factors. Reactive and experimental concurrency types were associated with other high-risk behaviours, such as drug use.
Department of Epidemiology, University of California, Los Angeles, CA 90024, USA. khess@ucla.edu
Kristen L
KL
Hess
Pamina M
PM
Gorbach
Lisa E
LE
Manhart
Bradley P
BP
Stoner
David H
DH
Martin
King K
KK
Holmes
D000328:Adult; D001294:Attitude to Health; D005006:Ethnicity / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D012309:Risk-Taking; D018571:Sentinel Surveillance; D017678:Sex Distribution; D012725:Sexual Behavior / Q000706:statistics & numerical data*; D012747:Sexual Partners; D012749:Sexually Transmitted Diseases / Q000453:epidemiology*; D019966:Substance-Related Disorders / Q000453:epidemiology; D014481:United States / Q000453:epidemiology; D047568:Unsafe Sex / Q000706:statistics & numerical data; D055815:Young Adult