MedPath

Behavioral Intervention to Reduce Sexual and Injection Risks Among Female Sex Workers Who Also Inject Drugs in Mexico

Phase 2
Completed
Conditions
HIV Infections
HIV
Interventions
Behavioral: Interactive injection and sexual risk intervention
Behavioral: Lecture-format presentation
Behavioral: Interactive Injection Risk Intervention
Behavioral: Interactive Sexual Risk Intervention
Registration Number
NCT00840658
Lead Sponsor
Steffanie Strathdee
Brief Summary

The investigators propose a highly efficient four-arm (factorial) trial to simultaneously test the efficacy of two behavioral interventions aimed at:

* increasing condom use in the context of ongoing drug use and

* decreasing needle and paraphernalia sharing

among female sex workers who also inject drugs in two Mexican-U.S. border cities: Tijuana and Ciudad Juarez.

Detailed Description

Our specific aims are:

* Aim 1: To evaluate the efficacy of a behavioral intervention to decrease sharing of syringes and injection paraphernalia among FSW-IDUs. We hypothesize that FSW-IDUs in the active experimental injection risk reduction condition will report: (a) less receptive and distributive needle sharing; (b) less sharing of injection paraphernalia; (c) obtaining syringes and injection paraphernalia from safer sources.

* Aim 2: To evaluate the efficacy of a behavioral intervention to increase condom use among FSW-IDUs in the context of ongoing drug use. We hypothesize that FSW-IDUs in the active experimental sexual risk reduction condition will: (a) report less unprotected vaginal and anal sex; and (b) have fewer incident cases of specific STIs.

* Aim 3: To evaluate the joint effects of these two behavioral interventions to increase condom use and reduce sharing of needles and syringes/injection paraphernalia among FSW-IDUs. We hypothesize that the joint effect of these interventions will generate greater risk reductions compared to either intervention alone.

* Aim 4: To determine the extent to which theoretically-important components of our interventions (i.e., self-efficacy, outcome expectancies, attitudes, intentions) represent underlying mechanisms of change in primary outcomes (i.e., sexual- and injection-related risk reductions).

* Aim 5: To explore subgroup differences in the efficacy of: a) the sexual risk reduction, and b) the injection risk reduction intervention based on background characteristics, contextual factors, social factors and intrapersonal factors.

Recruitment & Eligibility

Status
COMPLETED
Sex
Female
Target Recruitment
584
Inclusion Criteria
  • be biologically female
  • be at least 18 years old
  • report having exchanged sex for money, goods or drugs within the last month
  • report having injected drugs within the last month
  • report having unprotected vaginal or anal sex at least once in last 30 days
  • report sharing needles/syringes or other injection paraphernalia (i.e., cottons, cookers, water) at least once in the last month
  • live in Tijuana, Ciudad Juarez or its suburbs, as determined through municipal boundaries in each city
  • test HIV-negative at baseline
  • agree to receive antibiotic treatment for chlamydia, gonorrhea, syphilis trichomonas vaginalis or bacterial vaginosis if they test positive at baseline.
Exclusion Criteria

If women report:

  • consistent use of condoms for vaginal and anal sex with all male partners during the previous month
  • not being able to provide verification of injection drug use (i.e. track marks)
  • not sharing needles/syringes or paraphernalia at least once in the last month
  • being under 18 years of age
  • being male or transgender
  • being incapable of giving informed consent
  • planning to permanently move outside of the municipal boundaries of Tijuana or Ciudad Juarez within the next year.

Study & Design

Study Type
INTERVENTIONAL
Study Design
FACTORIAL
Arm && Interventions
GroupInterventionDescription
Group DInteractive injection and sexual risk interventionInteractive injection and sexual risk intervention: In each city, 75 women will participate in the 60 minute "Di No a las Jeringas Contaminadas" \['Say No to Contaminated Syringes'\] and "Di No Al Sexo Inseguro" \[Say No to Unsafe Sex'\] counseling session. This one-on-one intervention incorporates elements of MI and principles of Social Cognitive Theory and Theory of Reasoned Action (SCT/TRA) to address the context of both, a) unsafe injection sharing and the extent to which syringes and other injection paraphernalia is shared; and b) unsafe sex and condom use with clients, and associated risks (e.g., HIV (Human Immuno-deficiency Virus), STIs (Sexually Transmitted Infections), pregnancy).
Group ALecture-format presentationDidactic safer injection \& sexual activity education: In each city, 75 women will participate in a 60 minute lecture-format presentation and printed materials on safer sex and safer injection based on CDC guidelines for HIV counseling, testing, and referral and materials from Mexico's National Center for AIDS Studies (CENSIDA). In this component, there will be no theory-driven active skill building elements oriented towards safer sex or safer injection.
Group BInteractive Injection Risk InterventionInteractive injection risk intervention and didactic safer sex education: In each city, 75 women will participate in the 60 minute "Di No a las Jeringas Contaminadas" \['Say No to Contaminated Syringes'\] counseling session. This one-on-one intervention incorporates elements of motivational interviewing (MI) and principles of Social Cognitive Theory and Theory of Reasoned Action (SCT/TRA) to address the context of unsafe injection sharing and the extent to which syringes and other injection paraphernalia is shared. In addition, participants will be provided a lecture-format presentation on safer sex. However, in this component, there will be no theory-driven active skill building elements oriented towards safer sex.
Group CInteractive Sexual Risk InterventionInteractive sexual risk intervention and didactic safer injection education: In each city, 75 women will participate in the 60 minute "Di No Al Sexo Inseguro" \[Say No to Unsafe Sex'\] counseling session. This one on one intervention incorporates elements of MI and principles of Social Cognitive Theory and Theory of Reasoned Action (SCT/TRA) to address the context of unsafe sex and condom use with clients. In addition, participants will be provided a lecture format presentation on safer injection sharing. However, in this component, there will be no theory-driven active skill building elements oriented towards safer injection behavior.
Primary Outcome Measures
NameTimeMethod
Combined HIV/STI 12-month Incidence Rates of HIV, Syphilis, Chlamydia, Gonorrhea and Trichomonas Vaginalis.12 months, with measuring points at baseline and at 4, 8, and 12 months past baseline

Combined incidence for HIV/STI was calculated over the 12-month study period and included only those who a) had at least one follow-up visit and b) at baseline tested negative for HIV and any of the aforementioned STIs.

In the calculations we accounted for the time each participant spent at risk of HIV/any STI during the follow-up period, by using available information on each participant for each time point (i.e. baseline, 4-, 8-, and 12-months was used).

The analytic method used for this outcome analysis was Poisson regression with robust variance estimation. The outcome variable was a binary variable indicating whether a participant has contracted HIV or a new STI during the 12-month follow-up period. The primary factor of interest was the intervention group. The log ("time spent at risk of HIV/any STI") was used as an offset variable in order to account for the time spent at risk of HIV/any STI by each participant.

Secondary Outcome Measures
NameTimeMethod
Change (Baseline to 4-, 8-, and 12-months) in the Mean Number of Unprotected Sex Acts With Clients.12 months, with measuring points at baseline and at 4, 8, and 12 months past baseline

The analytic method used for a) was negative binomial regression with the number of unprotected sex acts with clients as the outcome variable and intervention group, time point (baseline, 4-, 8-, and 12-months), and the interaction between the two as the main effects of interest.

Change (Baseline to 4-, 8-, and 12-months) in the Proportional Odds of Higher Receptive Needle Sharing12 months, with measuring points at baseline and at 4, 8, and 12 months past baseline

For a) we asked: "In the past month, how often have you used a needle or syringe that you knew or suspected had been used before by someone else?" (possible responses: 1=never, 2=sometimes, 3=about half the time, 4=often, 5=always), with a higher response indicating a higher risk. The intervention effect was evaluated by conducting ordinal logistic regression, with the frequency of receptive needle sharing as the outcome variable and Group (Intervention vs. Control), Visit (Baseline, 4-months, 8-months, and 12-months) and the interaction term between the two (Visit\*Group) as the main effects. Our primary interest was the Visit\*Group interaction, with a significant corresponding p-value being indicative of an intervention effect.

Change (Baseline to 4-, 8-, and 12-months) in the Mean Score of the Injection Risk Index (IRI).12 months, with measuring points at baseline and at 4, 8, and 12 months past baseline

The injection risk index (IRI) was calculated by averaging the responses to the following five questions:

1. In the past month, how often have you used a needle or syringe that you knew or suspected had been used before by someone else?

2. In the past month, how often was a new syringe used to divide the drug?

3. In the past month, how often did you use a bottle-cap/spoon/cooker after someone else had used it?

4. In the past month, how often did you use a cotton filter for a needle after someone else had used it?

5. In the past month, how often did you use rinse water to clean needles after someone else had used it? The possible responses to the questions were coded as follows: 0=never, 1=sometimes, 2=about half the time, 3=often, 4=always. Before averaging the responses to the five questions, the responses to the second question were reversed coded to yield the same direction as the responses to the other four questions. IRI range: 0-20. Higher IRI--\>higher risk.

Trial Locations

Locations (2)

PrevenCasa, AC

🇲🇽

Tijuana, Baja California, Mexico

Sadec-Femap

🇲🇽

Ciudad Juarez, Chihuahua, Mexico

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