Couple-based risk counselling reduces rates of unprotected sex in HIV-negative drug-using couples, investigators from New York report in the on-line edition of the Journal of Acquired Immune Deficiency Syndromes.
Results of the study also showed that the counselling had a positive impact on drug-using behaviours.
The investigators believe their findings “provide robust evidence of efficacy of the couple-based HIV prevention intervention.”
Drug users are a high-risk group for HIV and other sexually transmitted infections. Injecting drug use poses the risk of the transmission of HIV and other blood-borne infections, and rates of unprotected sex are high among drug-using populations.
These risks are especially prevalent in couples where one or both partners use drugs. A number of studies have shown that couple-based counselling can reduce HIV risk behaviours. However, no study has previously looked at the efficacy of this intervention in HIV-negative heterosexual drug-using couples.
Therefore, between 2005 and 2010 investigators from Columbia University, New York, undertook a randomised controlled trial involving 282 HIV-negative heterosexual drug-using couples.
The couples were randomised into three arms.
- Those in the first received couple-based risk reduction counselling.
- Couples in the second arm also received risk-reduction counselling, but on an individual basis.
- The couples in the third arm acted as a control population and received general health promotion information, focusing on diet, exercise, access to health services, and screening for chronic diseases.
Most of the couples were recruited via street outreach. The interventions consisted of seven sessions lasting two hours which were delivered on a weekly basis. The impact of the interventions on unprotected sex and rates of sexually transmitted infections was assessed immediately after the interventions were completed and then six and twelve months later.
Participation rates were high and between 66% and 76% of couples attended all seven counselling sessions. Moreover, there was a high retention rate with 87% completing the post-intervention assessment and 76% the twelve-month assessment.
“The high participation, attendance and retention rates achieved in this trial demonstrate the feasibility of engaging impoverished street-based drug users, who remain at very high risk of HIV/STIs in a couple-based behavioral intervention,” comment the investigators.
There was a high prevalence of risky behaviour at baseline. Only one partner was required to have a history of recent drug use for the couple to be eligible to participate in the study. However, 82% reported that they had used drugs in the month before enrollment, 16% said they had injected drugs in the previous 90 days, and one-third of individuals had recently had sex outside their relationship.
Over the entire study period, there was a 30% reduction in the incidence of unprotected sex reported by participants who received risk-reduction counselling compared to those to were in the control arm.
Moreover, rates of unprotected sex were 29% lower for couples who received couple-based risk counselling compared to those who had individual risk-reduction counselling.
Risk reduction counselling had a significant impact on sexual risk behaviour immediately after the conclusion of the intervention (individual risk reduction [IRR] = 0.58; 95% CI, 0.38-0.88) and six months later (IRR = 0.70; 95% CI, 0.54-0.92).
Analysis was then restricted to the two risk-reduction arms. This showed that couple-based counselling had a significant effect on rates of unprotected sex at month six (30% reduction; IRR = 0.70; 95% CI, 0.51-0.96) and month twelve (41% reduction; IRR = 0.59; 95% CI, 0.35-0.99).
“These results suggest that when couples receive the intervention together, they are more likely to improve and sustain positive predictive behaviors over time compared to when one partner receives the intervention alone,” write the authors.
There were 23 incident sexually transmitted infections during the study and only one participant seroconverted for HIV.
The investigators also found that risk-reduction counselling had a “promising effect” on rates of injecting drug use.
“These findings draw attention to an effective intervention strategy that can be scaled up for drug-involved couples in harm reduction programs,” conclude the investigators, “a couple-based approach to primary prevention of HIV that addresses both drug and sexual risks and targets low income, urban, active drug users may help curb the HIV epidemic in the US and may have dissemination potential to address the global HIV epidemic.”