Ugandan study shows little evidence of increase in risky sex after HIV treatment roll out

The introduction of antiretroviral therapy in Uganda has been accompanied by only modest changes in sexual risk behaviour, investigators report in an advance online publication of the journal AIDS.

A research team lead by Dr Leigh Anne Shafter of the Ugandan Research Unit on AIDS monitored the sexual behaviour of both HIV-positive and HIV-negative individuals between 2002 and 2009.

Reported risky sexual behaviour fell around the time people started HIV treatment, but within two years started to increase again. However, the investigators stress that behaviour in 2008 was no more risky than it was before treatment with anti-HIV drugs was initiated.

Towards the end of the study, there was a slight increase in the rate of risk reported by HIV-negative individuals.

The investigators believe their findings show that HIV-prevention targeted at both infected and uninfected individuals is warranted, and therefore urge policy makers to “intensify messages” about sexual risk for both groups.

Studies looking at the impact of HIV therapy on sexual risk taking have produced conflicting results and are often limited by their short duration of follow-up. In addition, Most of the research has focused on HIV-positive patients, and it is unclear if the availability of effective treatment means that uninfected individuals are taking more risks.

Antiretroviral therapy became widely available in Uganda in 2004. A prospective study conducted between 2002 and 2009 in the south west of the country allowed researchers to monitor changes in sexual behaviour before and after the introduction of treatment.

The study sample included 669 individuals. They were aged between 15 and 85 years at the time of their recruitment, the majority (54%) being in the 25-44 age group.

A total of 455 individuals were HIV-positive and 55% of these patients started antiretroviral therapy.

Every three months participants were interviewed by the investigators about their sexual risk behaviour. They were asked to report new partners, and state their total number of partners, frequency of sex, rates of condom use, and indicate if had had intercourse in exchange for money or goods.

Among patients with HIV “sexual behaviour 2 or more years after ART [antiretroviral therapy] initiation was not significantly more risky than it was 2 or more years before ART for any indicator.”

Reported number of sexual partners, new casual partners, and frequency of sex all fell in the year after therapy was started. There were slight increases thereafter, but two or more years after the initiation of treatment reported risk behaviour was not significantly higher than that seen in the period two years before treatment was started.

Moreover, condom use with casual partners increased significantly after treatment was started. The investigators attribute this to “increased counselling intensity.”

However, only 17% of patients with a CD4 cell count below 50 cells/mm³ reported using condoms with casual partners. A similar proportion of individuals with very low CD4 cell counts also reported exchanging sex for money or goods. This worried the investigators, who think “poverty and the need for food may drive people with advanced HIV disease to more risky sexual behaviour at times when they are ill and highly infectious.”

Findings concerning the sexual behaviour of HIV-negative individuals were mixed. Risky sexual behaviour appeared to decline when the rollout of antiretroviral therapy started. The mean number of casual partners fell between 2002 and 2004, but by 2008 had increased significantly (p = 0.03). By late 2008, there was an increase of borderline significance in the number of reported recent sex partners.

The investigators comment, “the HIV uninfected population is substantially larger than the HIV-infected population. If risky behaviour among this population increases…then this behaviour will affect the impact ART has on the HIV epidemic.” They therefore call for prevention to targeted at “both HIV-infected and uninfected people.”