(Reproduced courtesy of Jon Faine Program, ABC Radio Melbourne).
Study reveals condom use not linked with increase in STIs among men using PrEP.
A recent study highlighted by Alfred Health and Burnet Institute research, has shown a 20 per cent increase in sexually transmitted infections (STIs) among men using HIV pre-exposure prophylaxis (PrEP) in a large Victorian PrEP study, PrEPX. The findings, published today in the prestigious Journal of the American Medical Association (JAMA) found, somewhat surprisingly, that condom use was not a significant predictor of acquiring an STI when using PrEP, and that STI risk was influenced more by numbers of casual partners and group sex.
The research used data from almost 3000 participants in PrEPX. The PrEPX Study was led by The Alfred hospital, with support from the Victorian Government, and Thorne Harbour Health (formerly the Victorian AIDS Council). Results were collated through the Australian Collaboration for Coordinated Enhanced Sentinel Surveillance of STIs and BBVs (ACCESS).
PrEP is a highly effective medication that can reduce HIV transmission by up to 99 per cent in people who are at risk of HIV infection. One of the concerns related to PrEP has been that it may lead to an increase in STIs if people reduce their condom use when they commence PrEP.
Among the key findings:
- In the study sample, PrEP was associated with a significant increase in STIs. The increase was also associated with participants in the study being tested for STIs more often as part of their regular PrEP prescribing clinic visits
- STIs were highly concentrated among a quarter of study participants who accounted for the majority of diagnoses
- This group experienced high rates of STI reinfection
- Participants reporting higher numbers of sex partners and participation in group sex were at greater risk of STIs
- Condom use made no significant difference in rates of STIs among the study participants.
Lead author, Burnet PhD student Michael Traeger, said the study findings suggest that STI prevention campaigns should not focus solely on condom use, but also on reducing the time to STI diagnosis and treatment through frequent testing.
“It’s important to understand that when people start taking PrEP, they also get tested more frequently, so STIs are more likely to be detected anyway,” Mr Traeger said.
“But as PrEP uptake increases, identifying individuals most at risk of STIs will become increasingly important for informing effective and focused STI prevention.”
The Principal Investigator of the PrEPX Study and co-senior author, Associate Professor Edwina Wright, an infectious diseases physician and clinical researcher at The Alfred, Monash University, and Co-Head of the HIV Elimination Program at Burnet Institute, said the findings are a rebuttal to the backlash against PrEP users for reducing condom use.
“The findings are also important because they highlight the need to target our sexual health messaging about STI risks to a relatively small proportion of PrEP users to help reduce their STI rates. We need to address these findings by engaging in more research to prevent STIs including STI vaccines and antibiotics that may prevent STIs,” Associate Professor Wright said.
Burnet Head of Public Health and co-senior author, Professor Mark Stoové said the strength of this research centred on the innovative use of surveillance data.
“Being able to identify STI risk down to an individual patient level provides findings that are internationally novel and paints a more informative picture for policy and practice than previous studies have been able to achieve,” Professor Stoové said.
“This study will be part of the evidence that I think will inevitably change guidelines in other jurisdictions to facilitate more frequent, quarterly testing.”
Thorne Harbour Health CEO Mr Simon Ruth added: “This study highlights that PrEP is more than a pill for HIV prevention. It’s a highly effective sexual health strategy that includes quarterly STI testing that interrupts the onward transmission of other STIs.
“We now have an opportunity to further assist gay men in looking after their sexual health by exploring more targeted strategies for those at higher risk of STIs.”
Key media contacts:
Head, Communications, Burnet Institute
Mob: 0403 755 082
Manager, External Affairs and Media, Alfred Health
Mob: 0410 404 737