The results of the Russian PREVENT trial demonstrate that an HIV prevention intervention targeting sexual behaviors of alcohol and drug users is feasible in inpatient substance abuse treatment settings and suggest that it is effective in increasing any condom use. A clinically important intervention effect was observed in the hypothesized direction for the other primary outcome, a 3-month period of no unprotected sex; however, the effect was not statistically significant.
Identification of an effective sexual risk reduction program in Russia is particularly valuable, as heterosexual transmission is the next anticipated phase of the HIV epidemic driven heretofore by injection drug use [
47]. A limited number of HIV behavioral interventions are documented to be effective in this region of the world; few address sexual risk, and none address sex risk in individuals with addictions [
16,
48]. The Russian narcology hospital yielded a cohort with risky sexual behavior, confirming the need and providing a setting for an effective sexual risk reduction intervention addressing this high-risk population.
The Russian PREVENT intervention was developed based upon an existing model demonstrated to be efficacious in US STD clinic patients [
42] and recommended for dissemination by HIV prevention experts [
49,
50]. Few effectiveness studies have investigated whether an adapted STD prevention model can produce desired outcomes in new settings [
50]. Factors such as inadequate adherence to the originally evaluated programs or inadequate tailoring to the target population make these studies difficult to conduct [
50]. Contributing to the success of our adaptation was the likelihood that the adapted model was able to remain faithful to the core elements of the original efficacious model while still being culturally and contextually appropriate.
The intervention appeared to be more effective in alcohol-dependent patients than in drug-dependent patients. This finding is surprising, given the approximate 35% HIV prevalence among IDUs in the narcology hospitals and previous research suggesting that knowledge of positive HIV serostatus reduces unsafe sex [
27]. Of the 15 control participants who received brief post-test counseling due to their positive HIV infection status, 13 were IDUs; this exposure may have attenuated the difference in this relatively small subgroup analysis.
Russia's mass media campaign to encourage condom use may be valuable. However, agencies such as the World Health Organization and the US Centers for Disease Control and Prevention recommend that national HIV prevention efforts include both mass efforts (e.g. media) and intensive interventions targeted towards those at greatest risk for infection and transmission [
51,
52]. Targeted strategies that tailor interventions to personal HIV risk using a ‘teachable moment’ (i.e. a time of heightened personal risk perception, such as during an HIV or STD test) are believed to be particularly effective [
51,
53]. Such ‘intensive’ prevention interventions combined with HIV testing, such as the Russian PREVENT, may be particularly advantageous in populations who have very high HIV risk (e.g. substance-dependent people) [
54,
55].
Interestingly, exploratory analyses suggested that the intervention may be more effective at increasing the percentage of safe sex and no unprotected sex among those with less depressive symptoms. Future interventions should address the relationship of psychiatric comorbidities on HIV risk reduction.
When comparing the results of the current study with the RESPECT study, we observed similar magnitudes of effect for the outcome no unprotected sex; however, our study did not find a statistically significant effect on this outcome while the original study of 5758 subjects did. In RESPECT, subjects in the intervention arms were more likely to report no unprotected sex compared to the control arm at the 6-month visit [39% enhanced counseling versus 34% didactic messages; relative risk (RR) 1.14; 95% CI, 1.01-1.28; and 39% brief counseling versus 34% didactic messages; RR, 1.12; 95% CI, 1.00- 1.25]. The lack of statistical significance in the current study may be an issue of statistical power.
This study's findings are consistent with US research indicating that patients in detoxification centers are at high risk for STDs, including HIV, and that sexual risk reduction programs in these settings can be efficacious [
31,
32,
56]. A recent meta-analysis of US research demonstrated that more effective HIV prevention programs were comprised of comprehensive and fairly intensive program ‘packages’, including community-based out-reach, substance abuse treatment, sterile syringe access and enhanced HIV/STD counseling and testing [
32]. It is important to explore the utility of additional HIV prevention approaches for substance users that take into account the limited resources and existing systems available—as is the case for this study in Russia. This study provides insights not only on potential interventions for the Russian narcology hospital context; it also contributes to the growing work on the utility of brief risk reduction interventions for any patient in addiction treatment. Research up to this point has suggested some success, but has been inconclusive due to the small number of efficacy and effectiveness studies [
57,
58]. Notably, no previous comparable work has been conducted in eastern Europe.
At 3 months, there appeared to be an increase in safe sex in the control as well as the intervention group. Assessments conducted by telephone rather than ACASI showed improvements in sex risk behaviors in both the control and intervention groups (). This may have been due to factors such as exposure of the control participants to the extensive initial assessment, including an ACASI, availability of condoms (distributed to all subjects) or regression to the mean. Despite early changes, the control subjects' behavior returned toward baseline in the second 3 months, while the intervention group continued to improve. The findings of delayed sexual risk reduction effects observed in this study are consistent with previous HIV intervention research [
59-
62], and may perhaps be attributed to greater opportunity for intervention participants to change behavior over time [
61].
The study had some major strengths: demonstration that the PREVENT intervention could be implemented in two Russian narcology hospitals supports the strong likelihood for translation of this research into practice, and ability to engage this high-risk population at a ‘reachable moment’ (e.g. addiction treatment) in addition to a ‘teachable moment’. In St Petersburg, talented and well-trained personnel were available to provide the intervention, and similar personnel may exist elsewhere in these clinical settings. Another study strength was the heterogeneity of the research subjects in terms of gender, HIV status and substance use, supporting the notion that these results may be generalizable to the narcology patient population elsewhere.
The trial also had some limitations. Although impressive changes were reported using state-of-the-art methodology for assessing behavior change, behaviors were self-reported and participants could not be blinded to intervention status, allowing the possibility of social desirability bias. Although we were not able to obtain objective biological outcomes, we attempted to limit this bias by using ACASI technology and by using research associates who were not involved in delivering the intervention to assess outcomes. We were unable to address the number of safe sex acts with partners with discordant HIV serostatus, as we did not ask the subjects to identify the HIV serostatus of their sex partners. Also, the narcology hospital setting has a disproportionate number of men and a minority of HIV-infected patients, thus we were unable to address gender or HIV status in stratified analyses. Additionally, the international setting of this behavioral intervention study presented certain challenges to assessing the fidelity of the intervention as adapted to the Russian setting. Finally, our study was not designed to detect small-to-moderate treatment differences with high power. Moreover, adjustment for additional covariates resulted in further reduction of power. Nevertheless, all primary and secondary outcomes show clinically important differences in the hypothesized direction and the adjusted results are marginally significant for percentage of safe sex events and periods of unsafe sex, and statistically significant for any condom use.
In summary, this randomized controlled trial suggests that adaptation of a pragmatic, HIV prevention intervention may reduce risky sexual behaviors in substance-dependent patients attending Russian narcology hospitals. Dissemination of this effective intervention should be considered as a component of a broad strategy aimed at reducing HIV infections in eastern Europe and other settings.