Popular opinion leaders add no benefit to intensive HIV prevention

This article is more than 14 years old. Click here for more recent articles on this topic

HIV prevention using ‘popular opinion leaders’ is no more effective at reducing risky sexual behaviour and the incidence of sexually transmitted infections than prevention consisting of counselling, treating sexually transmitted infections, and condom provision, investigators report in the online edition of the Journal of Acquired Immune Deficiency Syndromes.

The prospective study was conducted in five countries with a high prevalence of HIV. The study’s findings were “contrary to expectations”, but the investigators believe that this was because of the intensive prevention offered to individuals in the control arm.

They note that such a level of prevention is often unaffordable in many resource-limited settings outside the context of clinical trials. By contrast, prevention programmes using popular opinion leaders have been shown to be highly cost-effective.

Glossary

control group

A group of participants in a trial who receive standard treatment, or no treatment at all, rather than the experimental treatment which is being tested. Also known as a control arm.

prospective study

A type of longitudinal study in which people join the study and information is then collected on them for several weeks, months or years. 

culture

In a bacteria culture test, a sample of urine, blood, sputum or another substance is taken from the patient. The cells are put in a specific environment in a laboratory to encourage cell growth and to allow the specific type of bacteria to be identified. Culture can be used to identify the TB bacteria, but is a more complex, slow and expensive method than others.

cost-effective

Cost-effectiveness analyses compare the financial cost of providing health interventions with their health benefit in order to assess whether interventions provide value for money. As well as the cost of providing medical care now, analyses may take into account savings on future health spending (because a person’s health has improved) and the economic contribution a healthy person could make to society.

matched

In a case-control study, a process to make the cases and the controls comparable with respect to extraneous factors. For example, each case is matched individually with a control subject on variables such as age, sex and HIV status. 

Peer education, involving the training and engagement of individuals from communities with a high risk of HIV to endorse prevention messages personally, has been shown to be help reduce risky sexual behaviour in some populations.

However, there is little information about the use of peer educators, or popular opinion leaders, in resource-limited settings.

Therefore, between 2002 and 2007, investigators from the US conducted a study in five countries with a high HIV prevalence to “evaluate rigorously” the use of such a prevention initiative.

Venues were selected in China, India, Peru, Russia and Zimbabwe. At all sites, screening and treatment for sexually transmitted infections were available, as were free or low-cost condoms. Half the sites were randomised to also provide a popular opinion leader intervention.

Follow-up lasted 24 months. At baseline, and then again after twelve and 24 months, all of the 18,147 individuals enrolled in the study were screened for HIV and other sexually transmitted infections, received extensive post-test counselling on each occasion and also underwent a 45-minute interview by a trained interviewer on sexual risk behaviour, alcohol and drug use, and symptoms of illness at each of the three follow-up visits.

Those randomised to the Community Popular Opinion Leader group of the study also received an intervention designed to mobilise the influence of local popular opinion leaders, who had undergone training in how to promote safer sex in everyday life amongst their usual contacts, tailored according to country and culture.

Interventions in the opinion leader arm took place in different settings according to country: trade school dormitories (Russia); urban wine shops (India); markets (China); barrios (Peru); villages (Zimbabwe). Venues within each country were randomised to the control arm or the intervention arm after matching for incidence of sexually transmitted infections.

The investigators compared reported rates of unprotected sex and new diagnoses of sexually transmitted infections (including HIV) between the two arms of the study.

At the end of the two years of the study, the proportion of individuals reporting unprotected sex had fallen by 33% in both study arms. Although the level of reduction varied between countries (11 to 64%), the use of popular opinion leaders was not shown to have an additional benefit in any of the settings.

Similarly, incidence of sexually transmitted infections fell by a comparable amount between the two arms of the study (approximately 20%).

However, closer analysis of the results showed that rates of genital herpes were lower in the popular opinion leader arm in both China (p = 0.012) and Russia (p = 0.016).

“Contrary to expectations, the community popular opinion leader intervention and its comparison condition produced similar, significant, and clinically relevant reductions in both STD incidence and self-reported extramarital unprotected sexual acts”, comment the investigators.

The investigators stress that the individuals in the comparison group had received intensive HIV and sexual health prevention services. It is important to note that the control arm did not represent the standard of care in existence in each country at that time. In China for example treatment for sexually transmitted infections is typically given in the form of Chinese herbal treatment dispensed by pharmacists, not antibiotic treatment.

Since the completion of the study, many of the components of the comprehensive prevention services available at the study sites have disappeared due to lack of funding. The investigators note that the ethics have been questioned of offering a comparison arm (in this case intensive counselling, testing and treatment) that cannot be sustained after the trial closes.

The investigators note that peer education programmes in the US have been shown to be highly cost-efficient. In the US, preventing any one HIV infection is estimated to have cost $40.

They suggest, “it is more likely to be feasible for a resource-poor community to sustain the community popular opinion leader intervention than the intensive AIDS comparison conditions.”

However, since this study did not compare intensive counselling and testing with the popular leader intervention alone, the potential impact of the latter intervention alone is unknown.

References

The NIMH Collaborative HIV/STD Prevention Trial Group. Results of the NIMH collaborative HIV sexually transmitted disease prevention trial of a community popular opinion leader intervention. J Acquir Immune Defic Syndr (advance online publication), 2010.