Sex partner selection, social networks, and repeat sexually transmitted infections in young men: a preliminary report

The sexual networks of racially diverse young men who have sex with men

Young men who have sex with men are at increased risk for HIV. Research with older men and high-risk populations suggests that network dynamics may contribute to the spread of infectious disease and HIV, but little is known about the sexual networks of young men who have sex with men. Utilizing a unique dataset, this study presents novel descriptive data about the sexual networks of racially diverse 17- to 23-year-old young men who have sex with men. Additionally, individual, partner, and network characteristics of these young men who have sex with men were examined as potential drivers of HIV, STI, and unprotected intercourse. Results indicated several partner- and network-level factors associated with HIV and associated outcomes.

Local public health systems and the incidence of sexually transmitted diseases

OBJECTIVES

We examined the associations of local public health system organization and local health department resources with county-level sexually transmitted disease (STD) incidence rates in large US health jurisdictions.

METHODS

We linked annual county STD incidence data (2005-2008) to local health department director responses (n = 211) to the 2006 wave of the National Longitudinal Study of Local Public Health Systems, the 2005 national Local Health Department Profile Survey, and the Area Resource File. We used nested mixed effects regression models to assess the relative contribution of local public health system organization, local health department financial and resource factors, and sociodemographic factors known to be associated with STD incidence to county-level (n = 307) STD incidence.

RESULTS

Jurisdictions with local governing boards had significantly lower county-level STD incidence. Local public health systems with comprehensive services where local health departments shoulder much of the effort had higher county-level STD rates than did conventional systems.

CONCLUSIONS

More integration of system partners in local public health system activities, through governance and interorganizational arrangements, may reduce the incidence and burden of STDs.

Results of a randomized controlled trial of a peer mentor HIV/STI prevention intervention for women over an 18 month follow-up

Despite numerous behavioral interventions designed for women, rates of HIV and STIs are increasing. Interventions are needed that reach a large number of at-risk individuals. This study was a randomized clinical trial of a HIV/STI behavioral intervention conducted in Baltimore, MD, USA. Heterosexual women (n = 169) completed a baseline and three semiannual follow-up visits. Participants were randomized into a standard of care comparison condition or a Peer Mentor condition. At the 6-month follow-up, Peer Mentors were less likely to have multiple sex partners [AOR: 0.28 (95% CI: 0.13, 0.63)]. At the 18 month follow-up assessment, Peer Mentors increased their condom use during vaginal [AOR: 0.47 (95% CI: 0.25, 0.87)] and anal sex [AOR: 0.24 (95% CI: 0.09, 0.68)] as well as with main [AOR: 0.41 (95% CI: 0.21, 0.77)] and non-main partners [AOR: 0.33 (95% CI: 0.14, 0.79)]. Peer education is a sustainable approach to change risky sexual behaviors.

Longitudinal associations among relationship factors, partner change, and sexually transmitted infection acquisition in adolescent women

OBJECTIVES

New sex partners put adolescents at increased risk for sexually transmitted infections (STIs), even when these sex partners are nonoverlapping. Although the risk of partner change is well described, little is known about its antecedents. We prospectively examined associations between relationship characteristics, partner change, and subsequent STI during intervals of "serial monogamy."

METHODS

As part of a longitudinal study, 332 adolescent women were interviewed and tested for gonorrhea, chlamydia, and trichomonas every 3 months for up to just over 6 years. Interviews covered partner-specific relationship characteristics and sexual behaviors. The quarterly interval, a 3-month period bracketed by interviews and STI testing, was the unit of analysis. We examined associations among relationship factors, partner change, and subsequent STI using a series of mixed regression models, controlling for age, STI at Time 1, and condom nonuse.

RESULTS

Age, lower relationship quality, and lower levels of partner closeness to friends and family predicted partner change from Time 1 to Time 2. In turn, partner change was associated with acquisition of a new STI at Time 2. Although relationship factors did not exert a direct effect on STI at Time 2, they improved partner change-STI model fit. Similar patterns were seen with each organism.

CONCLUSION

Relationship factors drive partner change, which in turn contributes to STI acquisition. STI prevention research may need to focus on the relationship antecedents to partner change, in addition to the partner change itself.

High-risk sexual behaviours and genital chlamydial infections in high school students in Southern Taiwan

Summary

The objective of this study was to determine the prevalence of high-risk sexual behaviours and sexually transmitted infections (STIs) and associated risk factors in Taiwanese high school students. Students in grades 10 and 11 (mean age: 15.9 ± 0.9; range: 13–20 years) at two schools were recruited. An anonymous online real-time computer-assisted self-interviewing questionnaire was designed to assess demographic factors and sexual behaviours. Urine specimens were tested for genital chlamydial and gonococcal infections. The same survey and screening was conducted one year later on the same group of students. Overall, 670 individual students (993 visits) were enrolled with 323 students in both surveys. Twenty-seven percent had had sexual intercourse, and more than three quarters (79%) of them had engaged in high-risk sexual behaviours. Having friends using drugs increased the odds of practicing high-risk sexual behaviours (odds ratio [OR] 1.99, 95% CI: 1.13 to 3.50). Among 182 sexually active students, 8.8% had chlamydial (female: 12.5%; male: 5.3%) and 1.1% had gonococcal infections. Having sex with someone met on the Internet was the most significant risk factor for acquiring chlamydia (OR 8.14, 95% CI: 2.82 to 23.51). In conclusion, this adolescent population reported high prevalence of high-risk sexual behaviours and had a high prevalence of chlamydia supportive of a potential epidemic of STIs and HIV.

Egocentric network data provide additional information for characterizing an individual's HIV risk profile

OBJECTIVE

We investigated the hypothesis that partner-specific characteristics are important to improve an individual's risk characterization.

DESIGN

It has been shown that the egocentric network structure is important to establish a person's risk for infection.

METHODS

The study was cross-sectional in its design and enrolled 1231 volunteers at one HIV testing site in Rio de Janeiro, Brazil, and applied an adapted ego-network questionnaire. Each individual was interviewed about their own risk factors and those related to up to 10 sex partners. We used the dyadic data analysis method in which each relationship forms a record. Two receiver operator characteristic curves were generated, and the ability to correctly predict volunteers' HIV serostatus based on a model with characteristics of volunteers and sex partners and another with only volunteers' characteristics was evaluated.

RESULTS

Partner-related variables were associated with HIV serostatus both for men and women. The model with volunteer/sex partners' characteristics performed better in discriminating between HIV-positive and negative volunteers only for men but not for women. The c statistic for men volunteers was 0.82 [95% confidence interval (CI) 0.77-0.87] for the volunteer alone model and 0.88 (95% CI 0.86-0.91) for the combined model (P = 0.03). The values for women were 0.75 (95% CI 0.65-0.86) and 0.78 (95% CI 0.71-0.85), respectively (P = 0.71).

CONCLUSION

Ego-network theory-based approaches provide additional information for characterizing risk for HIV infection among men.

Comparison of sexual partnership characteristics and associations with inconsistent condom use among a sample of adolescents and adult women diagnosed with Chlamydia trachomatis

BACKGROUND

This analysis compared characteristics of female adolescent and adult sexual partnerships and related these characteristics to inconsistent condom use.

METHODS

Data are from a study of 126 women with prevalent chlamydia infections who reported information about 172 sexual partnerships in the previous 3 months. Characteristics of sexual partnerships included type of partner (main vs. other), duration of sexual relationship (<3 months vs. > or =3 months), partner age difference (<2 years older vs. > or =2 years older), and two scale measures: overlap of social networks (a measure based on how well the participant knew her partner's friends, for example) and intimacy.

RESULTS

Compared with adult partnerships, adolescent partnerships were of shorter duration and had less social overlap but were more likely to be classified by the participants as main partnerships. Among adolescents, longer partnership duration was not associated with higher intimacy, yet higher intimacy was significantly correlated with inconsistent condom use.

CONCLUSIONS

These differences suggest that adolescent females perceive and characterize their sexual relationships differently from adults. This, in turn, may have implications for risk of sexually transmitted infections (STIs). Prevention efforts for adolescents, including interventions and counseling, should consider the nature of their sexual partnerships.

African-American female adolescents who engage in oral, vaginal and anal sex: "doing it all" as a significant marker for risk of sexually transmitted infection

African-American female adolescents who engaged in vaginal sex only (N = 272) were compared to adolescents who engaged in two types (vaginal plus oral or anal; N = 295) and three types (vaginal, oral and anal; N = 144) on a constellation of other sexual risk behaviors (SRBs) and on sexually transmitted infections (STIs). Adjusted contrasts among groups revealed that adolescents who engaged in two and in three types of sex as compared to those who engaged in vaginal sex only were more likely to engage in six of the seven SRBs, but were just as likely to have a STI. One SRB, having >/= 4 lifetime sex partners, was in turn associated with STI. Two-way interactions indicated that having a casual sex partner and having multiple sex partners in the last 60 days increased the likelihood of STI, but only for adolescents who engaged in all three types.

Variations in sexual risks in drug users: emerging themes in a behavioral context

Drug users are an especially complex population among those studied in HIV risk behavior research. Although injection drug use accounts for over one third of the cumulative HIV transmission in the United States, the scope of the direct and indirect impacts of all drug use is difficult to quantify, especially in relation to attributing HIV to drug use directly, via parenteral exposures, or indirectly, through unsafe sex. Important behavioral issues such as social and drug network overlaps, partner selection, and the combinations of illicit drugs with erectile dysfunction medications have added complexity to the study of sexual behavior in drug users. This review covers recent substantive research in the United States and Canada on current themes in sexual risk behavior in injection drug and non-injection drug users. We address gender, situational, and sexual preference factors that may influence sexual behaviors affecting HIV risk by class of drug and route of administration. Special attention is paid to minority populations, both sexual and racial/ethnic, as their marginalized role in contemporary society places special barriers to risk reduction.

Chlamydial and gonococcal reinfection among men: a systematic review of data to evaluate the need for retesting

This study aimed to systematically review and describe the evidence on chlamydia and gonorrhoea reinfection among men, and to evaluate the need for retesting recommendations in men. PubMed and STI conference abstract books from January 1995 to October 2006 were searched to identify studies on chlamydia and gonorrhoea reinfection among men using chlamydia and gonorrhoea nucleic acid amplification tests or gonorrhoea culture. Studies were categorised as using either active or passive follow-up methods. The proportions of chlamydial and gonococcal reinfection among men were calculated for each study and summary medians were reported. Repeat chlamydia infection among men had a median reinfection probability of 11.3%. Repeat gonorrhoea infection among men had a median reinfection probability of 7.0%. Studies with active follow-up had moderate rates of chlamydia and gonorrhoea reinfection among men, with respective medians of 10.9% and 7.0%. Studies with passive follow-up had higher proportions of both chlamydia and gonorrhoea reinfections among men, with respective medians of 17.4% and 8.5%. Proportions of chlamydia and gonorrhoea reinfection among men were comparable with those among women. Reinfection among men was strongly associated with previous history of sexually transmitted diseases and younger age, and inconsistently associated with risky sexual behaviour. Substantial repeat chlamydia and gonorrhoea infection rates were found in men comparable with those in women. Retesting recommendations in men are appropriate, given the high rate of reinfection. To optimise retesting guidelines, further research to determine effective retesting methods and establish factors associated with reinfection among men is suggested.

Sexual behaviors after universal screening of sexually transmitted infections in healthy young women

OBJECTIVE

To prospectively study the relationship between diagnosis of sexually transmitted infections (STIs) at entry to U.S. Marines recruit training and subsequent sexual behaviors during vacation.

METHODS

Of all women entering recruit training (June 1999-June 2000), 2,157 (94%) voluntarily enrolled. At baseline, women received universal screening for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis and treatment and counseling for positive STIs. Recruit training (13 weeks) precluded any social activities. Unrestricted vacation followed (median 10 days). After training resumed (3 weeks), questionnaires and repeat STI screening were administered. Multivariable logistic regression examined STI diagnosis at baseline as a predictor for risky sexual behaviors at vacation and STI-positive diagnosis after vacation.

RESULTS

The study was completed by 1,712 (79%) women (median age 18 years); 1,038 reported sexual activity during vacation; 71% used condoms inconsistently; 19% had casual partners. At baseline, 152 (15%) tested STI-positive. Baseline STI diagnosis was unrelated to inconsistent condom use, nonmonogamous partnerships, or multiple partnerships. However, women testing STI-positive at baseline were more likely to test STI-positive after vacation (adjusted odds ratio 3.74, 95% confidence interval 2.10-6.65). Baseline STI diagnosis predicted casual partnerships among women aged 19-21 years (adjusted odds ratio 2.48, 95% confidence interval 1.12-5.50).

CONCLUSION

Substantial numbers of women engaged in risky sexual behaviors after universal STI screening and counseling. Compared with STI-negative women, STI-positive women were at increased risk for subsequent STI acquisition regardless of their similar behaviors. As universal STI screening is increasingly implemented, follow-up care will likely be required to further reduce risky behaviors and address network-level factors.

LEVEL OF EVIDENCE

II.

Age-bridging among young, urban, heterosexual males with asymptomatic Chlamydia trachomatis

OBJECTIVES

To determine the prevalence of age-bridgers among urban males aged 14-24 years, asymptomatically infected with chlamydia and to determine factors that distinguish age-bridgers from non age-bridgers. An index was defined as an age-bridger if within 2 months, he had had at least two sexual partners who differed from him in age by > or =2 years.

METHODS

Infected males provided data about themselves and up to four sexual partners in the past 2 months. Bivariate and multivariable logistic regression was used in the analysis.

RESULTS

The prevalence of age bridging was 21% in Baltimore and 26% in Denver. In both cities, in bivariate analysis, age-bridgers and their partners engaged in significantly more risky sexual behaviours. In adjusted multivariable analysis after controlling for number of sexual partners, age bridging was associated with having a sexual partner in the past 2 months, who, at time of last sexual intercourse, was drinking.

CONCLUSION

Age-bridgers represented major proportions of the study populations and, along with their sexual partners, were more likely to engage in risky sexual behaviours. Male age-bridgers may be key players in the transmission of sexually transmitted infections among youth linking age-disparate sexual networks.