Intensive and targeted PEP counselling leads to less risky sex afterwards, fewer HIV infections

This article is more than 13 years old. Click here for more recent articles on this topic

People at higher risk of HIV infection who take post-exposure prophylaxis benefit from an intensive programme of risk reduction counselling, American researchers report in the 1 July issue of Clinical Infectious Diseases. Participants made durable changes to their sexual behaviour and were less likely to have acquired HIV infection one year later.

The PEP counselling was based on detailed discussion of the sexual risks participants were taking. However other new research indicates that in the setting of routine clinical care for people with HIV in the UK, some clinicians are barely scratching the surface when it comes to asking about their patients’ sexual health and sexual risks.

Counselling for people taking PEP

Researchers in San Francisco wished to measure the impact of providing risk reduction counselling to people taking post-exposure prophylaxis (PEP) to prevent HIV infection. They measured changes in sexual behaviour one year later.

They randomised 457 people receiving PEP to either receive two sessions of standard counselling, or an enhanced programme of five counselling sessions.


post-exposure prophylaxis (PEP)

A month-long course of antiretroviral medicines taken after exposure or possible exposure to HIV, to reduce the risk of acquiring HIV.

risky behaviour

In HIV, refers to any behaviour or action that increases an individual’s probability of acquiring or transmitting HIV, such as having unprotected sex, having multiple partners or sharing drug injection equipment.

non-inferiority trial

A clinical trial which aims to demonstrate that a new treatment is not worse than another. While the two drugs may have comparable results in terms of virological response, the new drug may have fewer side-effects, be cheaper or have other advantages. 

statistical significance

Statistical tests are used to judge whether the results of a study could be due to chance and would not be confirmed if the study was repeated. If result is probably not due to chance, the results are ‘statistically significant’. 


A detailed research plan that describes the aims and objectives of a clinical trial and how it will be conducted.

The standard counselling intervention consisted of two sessions of 20 to 30 minutes each, individually tailored on the basis of social cognitive theory, motivational interviewing, and coping effectiveness training.  In the first session, the counsellor and participant explored the details and context of the risk exposure and developed a written risk reduction plan. At the second session a week later, the baseline HIV test result was given. The participant was asked about risk behaviour in the past week and the effectiveness of the risk reduction plan, which was adjusted if necessary.

People receiving the enhanced intervention received the same two sessions, as well as three further sessions, during which difficulties in implementing the plan were explored, contextual factors (such as particular places or emotions) that led to high or low risk behaviour were identified and an increasingly personal risk reduction plan was developed. (A detailed protocol for the five sessions is freely available on the journal’s website).

Adherence counselling was also separately provided on three occasions.

Almost all participants were men, and PEP had commonly been prescribed after unprotected anal sex (80.1%), unprotected vaginal sex (7.5%) or oral sex to ejaculation (5.9%) in the previous 72 hours. Four out of ten people receiving PEP knew that their partner was HIV-positive.

To assess the impact of the two styles of counselling, the behaviour of participants was assessed at the time of taking PEP and one year later.

When the data for all participants were analysed together, the extra intervention appeared to provide a modest benefit, but perhaps one that could not justify the cost of its provision.

The study’s primary outcome was change in the number of unprotected anal or vaginal sex acts. In the six months before taking PEP, participants had had unprotected sex an average of 5.5 times. In people who received two counselling sessions, this dropped by a mean of 1.8, while those getting the extra sessions had 2.3 fewer unprotected sex acts.

The results are more interesting if we only look at those individuals who were taking more sexual risks to begin with. A fifth of the participants had had unprotected sex four or more times in the six months before taking PEP, and the extra counselling had much more impact in this group.

In terms of the primary outcome, those with higher risk receiving the standard two sessions had a reduction in 7.0 unprotected sexual acts, whereas in those getting the extra sessions the average reduction was 13.2 acts.

Whereas 31.5% of higher-risk individuals receiving the standard intervention felt the need to come back for a second course of PEP within a year, this was case in 17.1% of those receiving five sessions.

And most importantly, fewer people were HIV-positive one year later. Among those with higher risk who received two sessions, 12.3% seroconverted. In those who received five sessions, 2.4% did so. (These infections are likely to be due to risk behaviour in the months after taking PEP, not the failure of PEP to prevent infection).

The researchers say that while, overall, two session counselling is non-inferior, this is not the case for those who have taken greater sexual risks. “For riskier individuals the three additional sessions may be necessary for risk behaviours to decrease,” they say.

Clinicians providing PEP need to take a sexual history in order to target additional counselling at those who would benefit from it.

While PEP can provide a benefit to individuals, the authors say that PEP will only make a public health impact “if it is targeted, used as a tool to leverage additional interventions, and the lessons learned from this study are adopted.”

Do clinicians discuss sexual behaviour with patients?

Meanwhile, an audit from the HIV clinic at Guy’s and St Thomas’ in London has found that only a minority of HIV-positive patients seen for follow up had recently had their sexual history reviewed by their HIV clinician. This is despite British HIV Association guidelines recommending that a sexual history should be taken every six months (and a full sexual health screen offered every twelve months).

Researchers audited the medical records of 60 newly diagnosed people and 90 patients attending for routine HIV care. Whereas a sexual history was recorded for 88% of newly diagnosed people, this was only the case for 37% of people attending for follow-up.

Different questions were asked of gay men and heterosexual people. Gay men were more likely to be asked about the number of sexual partners, the type of sex act and about sexual health check-ups, but tended not to be asked about having regular partners, the HIV status of regular partners and disclosing HIV status to regular partners. (These differences were all statistically significant).

None of the heterosexuals were asked about anal sex.

The researchers suggest that HIV clinicians should do more to assess their patients’ onward transmission risk and to provide behavioural interventions.


Roland ME et al. A Randomized Noninferiority Trial of Standard Versus Enhanced Risk Reduction and Adherence Counseling for Individuals Receiving Post-Exposure Prophylaxis Following Sexual Exposures to HIV. Clinical Infectious Diseases 53: 76-83, 2011. (Full text freely available online).

Soni O et al. Preventing onward HIV transmission in routine HIV care: low levels of evaluation of risk behaviour in HIV-infected patients. Sexually Transmitted Infections (published online ahead of print), 2011. doi:10.1136/sti.2010.049064