29 June 2021 

 A study of cisgender men and trans people who have sex with men has found that many of them know about PrEP, and commonly use it alongside other precautions to reduce the risk of getting HIV. The study participants had attended the Unity Sexual Health clinic in Bristol.

PrEP is a medication which reduces the risk of getting HIV. Until recently it was only available to people in the Impact trial or bought privately online but it has recently become freely available on the NHS to those who need it.

PrEP is highly effective at preventing HIV and is likely to have played a part in the dramatic decline in new HIV diagnoses in the UK among men who have sex with men. However, the rise in the use of PrEP may lead people to have more sex without a condom. This could cause an increase in other sexually transmitted infections (STIs), which can cause complications and increase antibiotic resistance.

Men who have sex with men and trans people who have sex with men who attended Unity Sexual Health were asked to complete an online questionnaire about why they went to the clinic, their sexual behaviour and views about PrEP. Some of these patients were also interviewed, to go into these issues in more detail. In all, 617 people who went to the clinic answered all of the questions and 24 were interviewed.

More than a third (35 per cent) of participants had taken PrEP before and, of those, 86 per cent were still taking it. Among non-PrEP users, 39 per cent didn’t know how to get it and 27 per cent couldn’t get a place on the Impact trial, even though 79 per cent were more at risk of HIV.

Among all those who didn’t have HIV or were unsure if they had it, 62 per cent were more likely to have unprotected anal sex with someone who they thought was HIV-negative if they themselves were using PrEP at the time.

Those interviewed were aware of PrEP and keen to use it. It was seen as ‘life-changing’, reducing their fear of acquiring HIV and anxiety about being tested for HIV, but the cost and it being hard to get stopped people using it more.

Interviewees used PrEP flexibly and also reduced their risk in other ways. They also knew about antibiotic resistance but still felt STIs were ‘curable’ at the moment. Knowing about antibiotic resistance rarely changed their decisions about sexual behaviour. But if antibiotic resistance became more widespread, they felt it may change their sexual behaviours.

Ava Lorenc from University of Bristol and NIHR ARC West and a lead author of the study, said: “Acknowledging the very positive aspects of HIV PrEP in terms of reduced risk and peace of mind for those taking it, this study shows the need for more public health messaging about STIs and antibiotic resistance.”

Dr Jane Nicholls, consultant in sexual health and HIV who led the study, said: “This study demonstrates that those who take PrEP are able to evaluate their own risk and use PrEP flexibly and appropriately. They do this not just for their own benefit, but to reduce the number of new HIV infections in the population as whole.

“We know that antibiotic resistance could make some STIs untreatable. If we can improve the public health messaging and involve PrEP users in shared decisions about testing and treatment, we could protect treatment options for the future.”

Dr Jeremy Horwood, from the NIHR Health Protection Research Unit in Behavioural Science and Evaluation at University of Bristol and co-author of the study, said: “Although PrEP awareness was high amongst clinic attendees in our study, those with a higher risk of acquiring HIV were more likely to report not knowing how to get PrEP as a common barrier to PrEP use. Improving access to PrEP  is an important step towards improving sexual health services for people at most risk of HIV infection.”

Paper: HIV pre-exposure prophylaxis (PrEP) knowledge, attitudes and perceptions of sexual health risk in an age of STI antimicrobial resistance by Ava Lorenc et al. Published in Sexually Transmitted Diseases.


Further information

About the NIHR Health Protection Research Unit [HPRU] in Behavioural Science and Evaluation at the University of Bristol 

The NIHR HPRU in Behavioural Science and Evaluation at University of Bristol is one of 14 HPRUs across England, part of a £58.7 million investment by the NIHR to protect the health of the nation. 

The NIHR HPRU in Behavioural Science and Evaluation is a partnership between Public Health England and University of Bristol, in collaboration with MRC Biostatistics Research Unit at the University of Cambridge and University of the West of England. 

Each NIHR HPRU undertakes high quality research that is used by PHE to keep the public safe from current and emerging public health threats.

About the NIHR 

The National Institute for Health Research (NIHR) is the nation’s largest funder of health and care research. The NIHR:

  • funds, supports and delivers high quality research that benefits the NHS, public health and social care
  • engages and involves patients, carers and the public in order to improve the reach, quality and impact of research
  • attracts, trains and supports the best researchers to tackle the complex health and care challenges of the future
  • invests in world-class infrastructure and a skilled delivery workforce to translate discoveries into improved treatments and services
  • partners with other public funders, charities and industry to maximise the value of research to patients and the economy.

The NIHR was established in 2006 to improve the health and wealth of the nation through research, and is funded by the Department of Health and Social Care. In addition to its national role, the NIHR supports applied health research for the direct and primary benefit of people in low- and middle-income countries, using UK aid from the UK government.