SEXUALLY TRANSMITTED DISEASES (STDs) are more likely to be acquired by adolescents than adults and the sequelae are especially problematic and costly in female adolescents.1 Because of a combination of biologic factors (e.g., cervical ectopy) and social factors (e.g., greater prevalence of STDs among their sex partners), African American adolescent females are particularly likely to be infected with an STD.1–3 Further, African American adolescent females living in the Southern United States experience disproportionately high rates of STDs.1,4–8 These infections contribute to multiple sequelae (e.g., pelvic inflammatory disease, infertility, pre- and postnatal complications) and exacerbate the risk of acquiring HIV through sexual intercourse.3,9,10
To enhance STD prevention efforts, an ongoing assessment of personal and contextual factors that may predispose adolescents to the acquisition of STDs is essential.11–13 Such assessment forms the basis for the design of intervention programs. Assessment efforts should be ongoing because each new generation of adolescents may be somewhat different from their predecessors. Moreover, although a socioecological approach to assessment efforts has been cited as an important strategy for identifying a diverse range of factors that may affect adolescents’ HIV-risk and acquisition of STDs, many studies to date continue to examine personal characteristics only while failing to expand the scope beyond the individual level.11
Methodological improvements in assessments must also occur on an ongoing basis. For example, the majority of past efforts have used one or more measures of condom use as the proxy for risk of STD acquisition.14 One problem with this approach is that condom use is only one of many behaviors that may ultimately determine the collective risk of STD acquisition.15 Further, misclassification bias may occur in the assessment of adolescents’ condom use behaviors.16,17 Fortunately, the advent of urine-based nucleic acid amplification assays has made the detection of 3 sexually transmitted infections (Trichomonas vaginalis, Chlamydia trachomatis, and Neisseria gonorrhoeae) relatively easy while providing excellent sensitivity and specificity.18–20 Thus, in addition to proxy measures, when resources allow and when it is feasible, studies of adolescents’ antecedents to STD acquisition should use laboratory confirmed acquisition. Accordingly, the purpose of this study was to identify risk factors associated with laboratory confirmed STD prevalence among low-income African American adolescent females living in a high-risk urban area of the Southern United States. Potential risk factors were selected based on findings from previous studies and represented a range of factors from the personal-level to the peer level.
Participants were 715 African American adolescent females enrolled in a randomized trial of an HIV prevention program. Only data collected at baseline (before any intervention occurred) were used for this study. Recruitment sites were an urban, publicly funded, STD clinic, a teen clinic based in a large public hospital, and a family planning clinic (all clinics were located in the same urban area of the South). From March 2002 through August 2004 project recruiters approached potential participants as they came to the clinic. Recruiters screened the female teens to assess their eligibility. Adolescents were eligible to participate if they were African American females, 15–21 years old, and reported sexual activity in the previous 60 days. Exclusion criteria were being married, pregnant, or attempting to become pregnant. Of 1558 screened, 874 adolescents were eligible and were asked to participate in the study. The study achieved an 82% baseline participation rate (N = 715). The Institutional Review Board at Emory University approved the study protocol before implementation.
Data collection included an audio-computer assisted self-interview (A-CASI) lasting about 60 minutes and a self-collected vaginal swab for NAAT to detect T. vaginalis, C. trachomatis, and N. gonorrhoeae. Participants were compensated in the amount of $50 for their completion of these procedures.
Based on evidence suggesting the possibility of decreased reporting bias,21 measures were assessed using A-CASI. By providing a voice track that delivered each question to adolescents through headphones, A-CASI technology may have reduced problems that otherwise would have been posed by illiteracy. For the current study, we selected variables that spanned from the personal- level to the peer and relational-levels and which have been empirically related to either sexual risk behavior or STD acquisition among adolescents.11–13 The psychometric properties for scale measures are presented in Table 1.
Personal Risk Factors.
Depressive symptomatology was measured using the shortened version of the Center for Epidemiologic Studies.22 STD/HIV-associated knowledge was measured with an index published by Sikkema et al.23 Previous studies suggest that sexual adventurism may be related to STD acquisition.24 We assessed sexual adventurism by asking participants if they had ever engaged in anal sex (yes or no) and how much they agreed with 9 sexually adventuristic statements, (e.g., “sex with a new partner is exciting to me”). Participants’ age, whether adolescents were currently using oral contraceptives and whether they had used marijuana and alcohol in the past 60 days were also assessed. Oral contraceptive use has been inversely associated with condom use thereby suggesting a similar relationship to STD acquisition.25,26 Moreover, oral contraceptive use may be an important control variable given the tendency for most combinations pills to exacerbate cervical ectopy thereby increasing susceptibility to STDs26 and alcohol and marijuana use have been shown to co-occur with STD acquisition.27,28 Finally, we assessed several sexual behaviors that have been related to STD acquisition such as the age at which they first had sex, whether they had used a condom at last sexual intercourse and the number of times they had not used a condom in the past 14 days.
Peer and Relational Risk Factors.
The bottom portion of Table 1 displays 4 risk factors and their respective psychometric information. Perceived peer support was measured by a 3-item subscale developed by Zimet et al.29 We also assessed whether participants had negative peer influences such as ever belonging to a gang, which may put them at greater risk of STDs.30 Power in relationships was adopted from Pulerwitz et al.31 Fear regarding consequences from condom negotiation with a sex partner and frequency of communication with a sex partner were both measured using scales adopted from previous studies.32–34 Other relational factors included asking adolescents whether they currently had a casual sex partner, whether they have sex with partners who are (on average) at least 2 years older than themselves and the number of sex partners they had in the past 60 days. These factors each have well established associations with unprotected sex35–38 whereas number of sex partners has been associated with risk of STD acquisition.38,39
Adolescents were instructed in the correct procedure for collecting a vaginal swab specimen using a model of the vagina to teach the correct technique. They were then asked to self-collect a vaginal swab specimen that was subsequently evaluated for T. vaginalis, C. trachomatis, and N. gonorrhoeae. T. vaginalis was assayed using the BDProbeTec ET Culturette Direct Dry Swab System (BD, Franklin Lakes, NJ).20 C. trachomatis and N. gonorrhoeae were initially assayed using the Abbott LCx Probe System (Abbott Laboratories, Abbot Park, IL).18 However, in September of 2002 (after testing 102 participants), this Abbot assay was discontinued, and we began using the BDProbeTec ET C. trachomatis and N. gonorrhoeae Amplified DNA assay (Becton Dickinson and Company, Sparks, MD).40
All continuous variables were assessed for normality by calculating their degree of skewness and kurtosis. Skewness and kurtosis ratios exceeding an absolute value of 2.0 were considered to be an indication of a nonnormal distribution (SPSS, v.14.0, Chicago, IL). Subsequently, all nonnormal continuous variables that were positively skewed were transformed by computing the logarithm; negatively skewed variables were reflected first (i.e., values were subtracted from the highest value of the scale plus 1), transformed by computing the logarithm and then rereflected to maintain the same direction of the original scale. The exception to this procedure was the measure of depression, which was dichotomized using the clinical cutoff score of 7 or less versus a score of 8 or more (with the latter indicating depressed affect).22 Associations between dichotomous risk factors variables and the outcome measure were assessed by the use of prevalence ratios, their 95% confidence intervals, and their respective P values. Associations between continuous risk factor variables and the outcome measure were assessed by independent samples t tests.
Variables achieving a screening level of significance (P <0.10) at the bivariate level were entered into a hierarchal multiple logistic regression model, using a forward stepwise method. The first block was designated to contain the control variables (age and number of sex partners in the past 60 days) if they achieved screening significance. The second block was designated to contain the remaining variables that achieved significance at the screening level. The logistic regression model was used to calculate adjusted odds ratios, their 95% confidence intervals, and corresponding P values of the predictors that remained significant in the multivariate analysis. Log-transformed variables included in the multivariate model were interpreted as 1% unit increase in the continuous variable scores would be associated with an increase/decrease of (unstandardized regression coefficient/100) risk for testing positive.
Characteristics of the Sample
Average age of the adolescents was 17.8 years (standard deviation = 1.72). The majority (65.3%) was students currently attending school. Nearly one-third (29.4%) of the sample reported having a paying job. The median level of education fell between grades 10 and 11. Overall, 206 adolescents (28.8%) tested positive for at least 1 of the 3 STDs: 17.6% adolescents tested positive for C. trachomatis, 12.9% tested positive for T. vaginalis, and 4.9% tested positive for N. gonorrhoeae. Adolescents (22.7%) tested positive for 1 STD, 5.7% tested positive for 2 STDs, and 0.4% tested positive for all 3.
Table 2 displays bivariate findings for the dichotomous personal- level risk factors. Of note, the obtained prevalence ratio for contraceptive use was protective indicating that those using oral contraceptives had a lower prevalence of STDs (the opposite of our expectation). Results of the t tests (not shown in table) indicated that adolescents testing positive were marginally younger (t(711) = 1.82, P = 0.07) and had less STD knowledge (t(713) = 2.32, P = 0.02) than those who tested negative. There was no differences between groups in age of sexual debut (t(709) = 1.45, P = 0.15) or sexual adventurism (t(713) = 0.48, P = 0.63).
Table 3 displays bivariate findings for the peer and relational-level risk factors. As shown, 1 of the 3 dichotomous measures achieved the screening level of significance. Results for the t tests (not shown in table) indicated that adolescents testing positive had more fear of consequences of condom use negotiation (t(713) = 3.04, P = 0.003) and perceived higher support from their peers (t(713) = 2.34, P = 0.02). There were no differences in number of sex partners in the past 60 days (t(711) = 1.30, P = 0.20), the frequency of communication about sex (t(713) = 0.76, P = 0.45) or power in relationships (t(712) = 0.77, P = 0.44).
The results from the multivariate logistic regression indicated that the model was significant (χ2 with 11 df = 55.52, P <0.00001) and achieved an outstanding fit with the data (Goodness of Fit χ2 with 8 df = 4.70, P = 0.79). Only 3 factors retained their significance. The strongest factor was whether adolescents had ever belonged to a gang. Compared with those who had never belonged to a gang, those who had were about 4.2 times more likely to test positive for at least 1 STD (95% CI = 2.16–9.44, P <0.001). Also, adolescents’ level of fear pertaining to condom use negotiation was positively and significantly related to testing positive such that a 50% increase in fear scores (e.g., going from a score of 10–15) resulted in twice as much risk of testing positive (B = 1.98, P = 0.005). Finally, adolescents’ perceived level of social support was also significantly and positively related to testing positive such that a 50% increase in peer social support scores (e.g., going from a score of 3–4.5) resulted in a 66% increase in testing positive for an STD (B = 1.32, P = 0.001).
Reduction of STDs is included in the Healthy People 2010 objectives. Before strides in this area can be made, ongoing assessments of various risk factors from multiple levels of influence and among varying populations most at risk must be made. The findings from this study are important because they are based on prevalence of laboratory-confirmed STDs, our sample is at heightened risk for STDs and the results expand our understanding of risk to contextual influences. Our results provide evidence suggesting that future interventions designed to address reductions in STD prevalence among African American adolescent females should include efforts that also consider the social-relational context in which these diseases are acquired.
Among our sample of African American adolescent females, we found a high prevalence of laboratory-confirmed STD (28.8%). A most notable finding is that contrary to what we would have expected, in the presence of peer and relational variables none of the personal-level risk factors included in our model achieved multivariate significance. One plausible explanation is that a more complex mediation model comprises these risk factors. Using mediation terms, it may be that the personal-level factors (the independent variables) may be causing the peer and relational level factors (the mediating variables), which in turn affect STD outcomes (dependent variable). Future studies should expand upon this possibility and test the strength of this model. If supported, the findings would suggest the utility of designing interventions that expand upon a focus of individual-level characteristics only and that seek to directly affect the social and relational aspects of these adolescents’ lives. Historically, the STD epidemic has been viewed largely as a personal-level phenomenon.11 Subsequently, many intervention efforts have targeted personal-level factors (e.g., condom use, knowledge, self-efficacy) as a means of achieving significant behavioral change. Yet, as our results suggest, merely examining personal-level determinants in isolation provides a limited perspective on a complex issue and, furthermore, precludes a more in-depth understanding of how social variables (e.g., peers, relationships) may be independently associated with STD risk behaviors in the presence of these other personal-level factors.
Most behavioral intervention programs targeting adolescents at risk have implemented programs designed to affect personal-level variables (e.g., decision-making, knowledge, skill-building).11,41 Although intervention programs that expand the focus beyond personal-level variables may look markedly different, it is important to note that these types of interventions may still be deemed “individual-level” approaches as they would target individuals (e.g., sex partners, peers) who exert significant influence on female adolescents’ behavior and sexual health. For example, such programs could be designed to involve current male sex partners. Involving male sex partners in an intervention makes sense given the lack of control females have in certain safer sex behaviors such as condom use. Negotiating the use of condoms with a sex partner may be problematic for some female adolescents especially those who are in power imbalanced relationships with their male partners.31,36,37,42 In fact, we found that fear of negative consequences following condom negotiation is associated with an increased risk for STD providing further support to involve male partners in an intervention program. Thus, a dyadic intervention could address more effectively these salient relational influences associated with STD risk and protective behaviors while also transferring the burden to initiate STD-protective behaviors from one person to the dyad.
Our findings also suggest that other peer-level factors may be beneficial foci for the design of interventions aimed to reduce STD risk among young African American females. The finding that history of gang involvement was strongly associated with STD prevalence is consistent with several other studies.13,30 Although a small percentage of girls in this study reported ever belonging to a gang, those who were involved in a gang were at increased odds of having an STD. Essentially, gangs are social groups organized around delinquent and antisocial behaviors.43 As such, being a member of a gang especially a female member of a gang increases the chance of victimization.44 With gang initiation practices such as being “sexed in” (i.e., having sex with multiple male gang members) and norms that view females as being sexually available and promiscuous, it stands to reason that being a gang member would heighten the risk for an STD. Previous research suggests that for young adolescent girls living in impoverished neighborhoods, ironically, belonging to a gang confers protection from crime, abusive families, and other gangs43,44 where the advantages far outweigh the disadvantages. Advantages include excitement, money-making opportunities, and peer relationships whereas the disadvantages would be possible victimization.44 Consequently, attempting to prevent girls from joining a gang may necessitate community-level or societal-level approaches that move beyond a focus on the individuals who live in the girls’ sphere of influence. Such approaches would include designing structural interventions that seek to alter the modifiable environments in which these girls live.
A significant related finding was that overall, regardless of gang involvement, greater perceived social support from peers was related to greater likelihood of testing positive for an STD. Previous research has found that family social support and social support in general is a protective factor for engaging in high risk behavior and acquiring STDs.45,46 Our measure of social support consisted of items tapping into adolescents’ perceptions of support from their friends only (e.g., “My friends really try to help me,” “I can count on my friends when things go wrong,” and “I have friends I can share my joys and sorrows with”). Thus, although this finding appears counterintuitive, it may be related to the qualities of the peer networks in which some of these adolescents girls inhabit. One potential explanation may be found from previous research, which has identified the significant influence of core social networks on the transmission of STDs within the network and to others who may be peripherally connected.47 Core social networks in this instance may comprise people who are linked through sexual contacts and who engage in high-risk behaviors. Adolescent females in this study who perceived higher levels of social support from their peers may be imputing their support from social networks that either involve people who are engaging in higher-risk sexual behaviors or who are sexually connected to another core group, who in turn engage in sexual risk behaviors and/or who have high incidence of STDs. This finding lends support for conducting a social network analysis that would assist in the mapping and measuring of relationships and flows between people who may be transmitting STDs. Social network analysis, although not novel, is an important epidemiologic approach and still provides a method for enhancing our understanding of the interaction of personal risk taking and the social context, which in turn can lead to more effective interventions.47–50
Taken together, these findings suggest the strong influence peers have on STD outcomes among this population. Whether the peer support stems from belonging to a gang or from conventional social networks is not necessarily the issue because both are related to a heightened increase of STD acquisition. These results imply that prevention programs designed to reduce STDs among this population must incorporate activities to affect the underlying direct contextual influences stemming from peer interactions as well as the indirect influences of neighborhoods and family on gang involvement as they are collectively contributing to STDs.
These findings are limited by the validity of the self-reported measures. Also, the study was based on a sample of economically disadvantaged African American adolescents. Therefore, the findings may not apply to other African American adolescent females or adolescent females from other racial/ethnic groups or different socioeconomic strata. Further research is needed with diverse adolescent populations. Also, we purposefully selected and limited the number of assessed correlates. This process was necessary to avoid the statistical power problems that can easily occur when an excessive number of correlates are entered into a regression model. Further studies, using these and other measures of personal and social correlates, are warranted.
A high percentage of young African American adolescent females face the reality of acquiring an STD including HIV unless programs can effectively reduce their risk. Although a challenge, the results from this study suggest placing interventions at levels that transcend the individuals directly affected. Such interventions could include male sex partners, attempt to identify sexual networks51,52 and would target peer influences and other factors related to joining a gang. This type of contextual focus may offer hope for ameliorating the escalating rates of STDs among this population.
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