An examination of perceived norms and exchanging sex for money or drugs among women injectors in Baltimore,MD,USA

Abstract

Injection drug users who exchange sex for money or drugs may serve as a bridge group for transmitting HIV between injectors and non-injectors. While many individual characteristics have been linked to exchanging sex, little attention has been given to the influence of social network members. The present study assessed the relationship between exchanging sex and perceptions of peers’ sex exchange behaviour and attitude toward sex exchange. The sample was composed of 267 women heroin and cocaine injectors in Baltimore, MD, USA. The results indicate that women who believed that their friends exchanged sex were more twice as likely to exchange sex in the past 90 days (95% CI: 1.49–2.70). Also, participants who thought their peers disapproved of sex exchange were 20% less likely to exchange sex (95% CI: 0.67–0.95). These findings suggest the need for peer education interventions that promote norms about safer behaviours.

Keywords

exchanging sex injection drug use HIV social networks norms women

Introduction

Many injection drug users (IDUs) exchange sex for money or drugs.^1,2 IDUs who exchange sex may serve as a bridge group for transmitting HIV between injectors and non-injectors. Demographic factors like marital status, employment and homelessness have been linked to exchanging sex.^3,4 Exchanging sex is associated with increased rates of sexually transmitted infections,⁴ HIV seropositivity^5,6 and behaviours, which may promote HIV/STI transmission like higher number of sex partners, having sex with a crack or injection drug user.^4,7

Hoffman et al.⁸ reported that frequency of crack use was associated with increased sex exchange encounters among 1723 women across 22 US sites. In a Canadian study of women injectors, Spittal et al.⁹ found that sex exchange was associated with daily use of heroin and crack. Likewise, Booth et al.¹⁰ reported that crack smokers and injectors who smoked crack were more likely to report exchanging sex compared with injectors only.

The social environment may have profound effects on sexual risk behaviours. Social networks refer to the group of people that an individual interacts with such as friends, family members, sex partners and drug partners. Social networks play a role in HIV and sexually transmitted infections (STI) transmission¹¹ and are associated with sexual behaviours like multiple sex partners¹² and condom use.¹³ Latkin et al.¹⁴ found that social network composition is associated with exchanging sex among a sample of drug users. Individuals who exchanged sex reported a higher number of crack smokers and a lower number of kin in their social network.

Exchanging sex is often viewed as a deviant and stigmatized behaviour and although initiation may be influenced by peers or sexual partners, few studies have examined peer influences that may promote or maintain ongoing sexual exchanges. The present study seeks further understanding of how social networks influence behaviour through promotion of norms. Norms represent an individual's perception of the perceived prevalence (descriptive norms) and perceived approval (injunctive norms) of a behaviour among peers.¹⁵ Specific types of norms are often referred to in the literature such as partner norms, which refer to the perceptions of sexual partners’ views about a certain behaviour, such as the acceptability of condom use.

Norms have been associated with sex behaviours among drug users. Among Dutch drug users, Van Empelen et al.¹⁶ found that injunctive norms were significantly associated with intention to use condoms with steady partners, but not with casual partners. Descriptive norms did not predict intention to use condoms with steady or casual partners.

In a study of women drug-using commercial sex workers (CSWs) Johnston et al.¹⁷ found that injunctive and partner norms predicted intention to use condoms, but this relationship varied by drug use. Among non-injecting CSWs, both partner norms and injunctive norms were significantly associated with intention to use condoms. However, among injecting CSWs, only partner norm, not injunctive norm, was related to condom use intention.

Although research has demonstrated that condom use is influenced by norms, less attention has been given to the influence of norms on exchanging sex for money or drugs. The purpose of this study is to examine the relationship between peer injunctive and descriptive norms and exchanging sex in a sample of women injectors. We chose to focus on women only since compared with men, women are much more likely to provide sex in exchange for money or drugs.

Methods

Individuals included in this project were participants in the STEP into Action (STEP) program, an HIV prevention intervention for drug injectors (primary participants) and their social network members (network participants).

Eligibility for primary participants included (1) ≥18 years; (2) Baltimore resident; (3) no participation in other HIV or network studies in the past year; (4) frequent cocaine or heroin injection in the past three months and (5) willingness to talk to network members about HIV prevention. The eligibility criteria for network members included: (1) ≥18 years; and one of the following behaviours in the past six months: (2a) cocaine or heroin use; (2b) used drugs with primary participant; (2c) shared needles with primary participants; (2d) shared cookers with primary participant; (2e) primary participant gave drugs when network had no money or (2f) sex partner of primary participant.

After written informed consent was received, participants participated in face-to-face interviews. Participants also provided an oral sample to test for HIV antibodies using the OraSure collection device (OraSure Technologies, Inc. Bethlehem, PA, USA) All study protocols were reviewed and approved by the Johns Hopkins Bloomberg School of Public Health Institutional Review Board prior to implementation.

Measures

Data on several sociodemographic characteristics were collected. Participants reported the number of different people they had oral, vaginal or anal sex with in the past 90 days. Exchanging sex was assessed by asking participants if they had oral, vaginal or anal sex with someone in the past 90 days to get money or drugs. Drug use was measured by asking participants about the last time and frequency of injecting drugs and smoking crack. HIV status was determined through laboratory assessment of the Orasure sample.

Perceived descriptive norm was measured by ‘How many of your friends have sex or turn tricks to get money or drugs?’ The perceived injunctive norm was assessed with ‘How many of your friends would disapprove if you were to have sex or turn a trick to get money or drugs?’ Response options for both items were a five-point scale ranging from none to all of my friends. There was a significant, but modest, correlation between the two norms variables (r = -0.266, P < 0.001).

Analyses

From March 2004-2006, 1027 baseline interviews were completed. The present study was restricted to women participants who were sexually active in the past 90 days and injected heroin or cocaine in the past 6 months (n = 267). A multivariate logistic regression model was composed of demographic and drug characteristics that were at least marginally significant at the bivariate level (i.e. P < 0.10). We included both types of norms in the model simultaneously to assess their independent effect in the presence of each other. Since social network members may have similar perceptions and behaviours, we accounted for possible clustering of responses through general estimating equations.¹⁸

Results

Sample characteristics

The majority of the sample was African-American, HIV-negative, and had a low socioeconomic status (Table 1). Approximately one-third of participants (n = 108, 35.2%) reported exchanging sex for money or drugs in the past 90 days.

Data in Table 1 are a comparison of women who exchanged sex and women who did not exchange sex. Women who exchanged sex were younger (P < 0.05), and marginally less likely to be married or in a committed relationship (P < 0.10) and more likely to be homeless (P < 0.01). More women who exchanged sex reported injecting daily (P < 0.05) and smoking crack in the past 90 days (P < 0.10). Finally, exchangers reported a higher number of sexual partners compared with women who did not exchange sex (P < 0.001).

Table 1

Demographic and drug-related behaviour comparison of women injectors who exchanged sex with women injectors who did not exchange sex (n = 269)

Characteristic	Did not exchange sex (n = 161)	Exchanged sex (n = 108)	χ^*
Age: Mean (SD)^†	41.2 (7.7)	39.2 (7.2)	2.19^‡
Race: African-American	132 (80.0)	88 (81.5)	1.64
Married or in committed relationship^§	76 (47.2)	39 (26.1)	3.25
Education: high school diploma or higher	78 (48.4)	44 (40.7)	1.55
Employed at least part-time	14 (8.7)	9 (8.3)	0.01
Total Income <$500 in past 30 days	59 (37.1)	49 (45.4)	1.82
Been homeless in past 6 months^¶	44 (27.3)	49 (45.4)	9.30
HIV positive	10 (6.7)	9 (9.5)	0.98
Total number of sex partners in past 90 days: Mean (SD)^#	1.35 (0.06)	7.46 (1.14)	-5.36^‡
Daily injection^†	87 (54.0)	72 (66.7)	4.27
Daily crack use	76 (47.2)	52 (48.2)	0.02
Smoked crack in past 90 days^§	115 (71.4)	88 (81.5)	4.49

Chi-square test statistic

†

P <0.05

‡

t-statistic

P< 0.10

P< 0.01

P, 0.001

Perceived norms

Perceived norms data are shown in Table 2. Twenty percent of non-exchangers believed that none of their peers exchanged sex while only 5.6% of exchangers did. On the other hand, 12.9% of exchangers believed that all of their friends exchanged sex compared with 1.9% of non-exchangers.

Table 2

Comparison of perceived norms between women injectors who exchanged sex with women injectors who did not exchange sex (n = 269)

Perceived norm	Did not exchange sex (n = 161)	Exchanged sex(n = 108)
Number of friends who exchange sex
None	33 (20.1)	6 (5.6)
A few	92 (58.2)	37 (34.3)
About half	18 (11.4)	26 (24.1)
Most	12 (7.6)	25 (23.2)
All	3 (1.90)	14 (12.9)
Number of friends who disapprove of exchanging sex
None	31 (19.4)	35 (32.4)
A few	38 (23.8)	33 (30.6)
About half	8 (5.0)	9 (8.3)
Most	20 (12.5)	14 (12.9)
All	63 (39.4)	17 (15.7)

While 19.4% of non-exchangers thought that none of their friends disapproved of sex exchange 32.4% of exchangers did. Thirty-nine percent of non-exchangers believed all of their friends disapproved of sex exchange while 15.7% of exchangers did.

Multivariate analyses

Unadjusted and adjusted odds ratios are shown in Table 3. Participants who believed their peers exchanged sex (descriptive norms) were twice as likely to exchange sex (95% CI: 1.49–2.70). Likewise, participants who perceived that their peers disapproved of sex exchange were 21% less likely to exchange sex (95% CI: 0.67–0.95). The relationships between exchanging sex and the demographic and drug variables were attenuated in the multivariate models.

Table 3

Multivariate model comparing women injectors who exchanged sex for money or drugs in the past 90 days with women injectors who did not exchange sex (n = 269)

Variables	Unadjusted odds ratio	95% confidence interval	Adjusted odds ratio	95% confidence interval
Descriptive norms	2.36^*	(1.78, 3.14)	2.00^*	(1.49, 2.70)
Injunctive norms	0.72^†	(0.62, 0.85)	0.79^†	(0.67, 0.95)
Age	0.96^‡	(0.93, 0.99)	0.98	(0.94, 1.01)
Married/in committed relationship	0.63^§	(0.38, 1.04)	0.86	(0.49, 1.53)
Homeless in past 6 months	2.20^†	(1.34, 3.63)	1.48	(0.84, 2.62)
Smoked crack in past 90 days	1.76^§	(0.97, 3.20)	1.54	(0.75, 3.16)
Injected daily	1.70^*	(1.02, 2.83)	1.47	(0.82, 2.64)

P 0.001

†

P 0.001

‡

P 0.01

P 0.10

Discussion

In this sample of women injectors, exchanging sex was associated with perceived prevalence and peer approval. The majority of non-exchangers perceived that their friends did not approve of exchanging sex. However, about two-thirds of women who exchanged sex reported that half or more of their friends exchanged sex while 80% of non-exchangers reported a few or more of their peers did. In the multivariate models, individuals who believed that peers exchanged sex for money or drugs were more likely to exchange sex. Also, individuals who perceived that their peers disapproved of exchanging sex were significantly less likely to report exchanging sex. The data suggest that exchanging sex is perceived to be a common, normative behaviour.

The association between descriptive norms and exchanging sex was stronger than injunctive norms. These findings suggest that among women injectors the perceptions of what peers are doing is more influential than peers’ approval of a given behaviour. Research on drug users have led to a concept known as differential affiliation, which posits that similar individuals associate with each other (i.e. birds of a feather flock together). Latkin et al.¹⁹ found that crack smokers tend to associate with other crack smokers while heroin sniffers associate with other heroin sniffers. Given the level of stigma in the larger society, it is not surprising that women who exchanged sex are likely to associate with other individuals who exchange sex.

We examined norms as both an ordinal and categorical variable (data not shown). In each of the analyses, the same findings were revealed. These data suggest that it does not take many individuals to influence their peers. A small group of peers is sufficient to promote norms that encourage or maintain ongoing exchanges.

Our findings suggest that individual behaviour may be shaped by perceptions of peer behaviour. Prevention efforts targeted at IDUs, must capitalize on the strengths and benefits of utilizing social networks to influence behaviour. Interventions are needed that encourage individuals who exchange sex to reduce their risk behaviours and alter existing group norms that may promote exchange. Peer-led interventions can have a positive effect through promoting safer behaviours. Peer education has been successful among both drug users²⁰ and sex workers.²¹ In this model, individuals may be trained on options to substitute the need to exchange sex such as setting aside money or drugs for a future occasion or identifying a peer that they can depend on when they are in need of money or drugs. Peer educators can talk to their peers about these safer strategies. Peer-to-peer communication has been shown to influence perceived norms among injections.²² In addition to communication, peer educators can model safer behaviours. By modelling safer behaviours, they promote a belief that exchanging sex is not the norm of the group. Also, peer educators can promote norms that discourage others from engaging in sex exchange.

In addition to network interventions, structural intervention such as drug treatment and increased economic opportunities are also needed. By instituting these structural interventions, women may have less of a need to exchange sex for drugs or money to purchase drugs.

Future research is needed to determine types and characteristics of the peers who are most influential. Our study focused solely on friends. It is possible that another group such as sex partners or drug partners may also influence sex exchange behaviours. Research on norms pertaining to sexual behaviours, such as condom use, has demonstrated that partners may be more influential than peers.¹⁷

Several limitations of this study should be noted. First, the data were cross-sectional. Longitudinal studies are needed to determine how perceived norms predict sex exchange behaviours. In addition, injectors who participated in the study may not be representative of the general IDU population since participants were self-selected. Finally, the data were self-reported; thus, some responses, such as drug use behaviours, may have been influenced by social desirability. We attempted to limit this bias by using ACASI (audio computer assisted self interview) for items on risk behaviours, including exchanging sex.

This study has provided evidence of the interplay among sex and drug behaviours. Public health researchers need to consider both types of risks because any successful change in one type of behaviour may not make a huge difference if the individual is still practicing other risky behaviours.

Footnotes

Acknowledgements

This work was funded by the National Institute on Drug Abuse (grant number 1RO1 DA016555).

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