Beliefs about AIDS drugs linked to risky sex, York study says


TORONTO, August 16, 2006 -- HIV-positive gay and bisexual men who believe current drug treatments make it more difficult to transmit the AIDS virus are much more likely to have risky sex than those who do not share this belief, a York University study has found.


Dr. Trevor Hart, a clinical psychologist and professor in York’s Department of Psychology, surveyed 554 gay and bisexual men who attended the 2005 Toronto Gay Pride Festival. The purpose of the study was to examine the relationship in Canada between risky sexual behaviour and beliefs about Highly-Active Anti-Retroviral Therapy (HAART) – the HIV/AIDS treatment cocktail that has been used so successfully since 1996 to prolong the lives of people living with HIV.


More than 81 per cent of those who participated in the survey were HIV-negative, 13.7 per cent were HIV-positive, and about five per cent were uncertain of their HIV status. They were asked about sex over the past six months with both short-term and longer-term partners. Risky sex was defined as unprotected insertive or receptive anal intercourse with partners of unknown or opposite HIV status.


“What we found was that HIV-positive men who believed the drugs make it much more difficult to transmit the virus were 3.5 to 10 times more likely to have unprotected sex with a partner whose HIV status was opposite to theirs, or unknown, than were the men who didn’t believe the drugs would prevent transmission,” says Hart.


The study shows there is a strong association between the beliefs about the drugs and risky sex – consistent with most American and other studies – although it is impossible to say whether the beliefs actually cause the risky sexual behaviour, says Hart. However, in contrast to most earlier studies, it also distinguishes between unprotected insertive and unprotected receptive sex.


It found, for example, that HIV-positive men who believed the drugs were effective at preventing transmission of the virus were six times more likely to have unprotected insertive sex with casual partners whose HIV status was negative or unknown. Among the much larger sample of men who were HIV-negative, those with the same beliefs about the drugs were three times as likely to have unprotected receptive sex with a longer-term partner whose status was positive or unknown.


The implications of the study’s findings are that some people who have these beliefs may be taking a little bit of knowledge about the HIV medications and relaxing their vigilance, says Hart.


“Gay and bisexual men are much better educated about AIDS than most heterosexuals, but we need to get the message out that while the drugs may reduce the risk of transmitting the virus, the viral load in a man’s genital tract may not be the same as in his blood sample,” says Hart. “So unprotected sex is still very risky for transmitting HIV.”




York University is the leading interdisciplinary research and teaching university in Canada. York offers a modern, academic experience at the undergraduate and graduate level in Toronto, Canada’s most international city.  The third largest university in the country, York is host to a dynamic academic community of 50,000 students and 7,000 faculty and staff, as well as 190,000 alumni worldwide. York’s 11 faculties and 23 research centres conduct ambitious, groundbreaking research that is interdisciplinary, cutting across traditional academic boundaries.  This distinctive and collaborative approach is preparing students for the future and bringing fresh insights and solutions to real-world challenges. York University is an autonomous, not-for-profit corporation.


For more information, please contact:


Janice Walls

Media Relations Coordinator

York University

416-736-2100, ext. 22101