Studies among MSM

Comparisons between groups before and after testing available

Some studies of sexual behaviour in MSM started before HIV testing was available, allowing comparisons of sexual behaviour before and after VCT was established.

A study from the United States followed a cohort of homosexual men from 1984, before HIV testing was available, until 1986 when HIV testing was available (Coates et al., 1987³⁰⁸). Men who were aware of their HIV status were significantly less likely to practise unsafe sex (12% of seropositive men, 18% of seronega-tive men and 27% of untested men practised unsafe sex). All groups had, however, started to change their sexual behaviour before HIV testing became available. All reported significantly higher rates of unprotected sexual intercourse before HIV testing was available (48% who ultimately tested positive, 49% who did not test and 41% who ultimately tested negative).

A study from the Netherlands also showed that MSM had started to change their sexual behaviour prior to VCT being made available (van Griensven et al., 1989³⁰⁹). They also showed that seropositive MSM were more likely to use condom during anal intercourse (with both steady and casual partners) than were seroneg-ative and untested MSM.

Inconclusive studies

Several studies suggested that although there were considerable reductions in risky sexual behaviour over time these were not clearly associated with VCT.

A study from Canada followed a cohort of homosexual men from 1984-1987 (Schechter et al., 1988³¹⁰). Following VCT, the annual number of sexual partners fell for both those with seropositive and seronegative test results and there was a marked increase in condom use. More seronegatives than seropositives reported no condom used during anal intercourse with regular partners (45.7% versus 23.4%) and with casual partners (15.9% versus 1.5%). (There was, however, no control group of untested). Asmall group of people who had the largest number of casual sexual partners was also the most likely not to be using condoms with these partners. Although marked risk reduction was noted for MSM who were aware of their HIV status, a few men continued to put themselves at extremely high risk.

A study from Chicago showed that all MSM decreased risky sexual behaviour but there was no significant difference between men who were aware of their HIV status and those who were not (Ostrow et al., 1989³¹¹).

A study from the United States compared MSE who were aware of their HIV status, with men who had been tested but declined to receive their test result (Doll et al., 1990³¹²). Both groups had access to risk-reduction information. In both groups there was a significant decline in unsafe sexual behaviour, but these declines were independent of knowledge of HIV status and actual serostatus.

In a longitudinal study of 139 MSM from Boston, all groups (seropositive, seronegative and untested) showed a decline in risky sexual behaviour, but there was no difference between the groups (Zapa et al., 1991³¹³).

Twenty-two seropositive MSM, twenty-two seronegative MSM and twelve men who were tested (but did not want to know their HIV status) were surveyed one week and six months after testing (Huggins et al., 1991314). All three groups altered their sexual behaviour, with no significant difference between the groups.

A study from four cities in the United Kingdom also showed no evidence for decreasing risky sexual behav-iour following VCT (Dawson et al., 1991³¹⁵).

In a study from 16 small cities in the United States there were mixed findings (Roffman et al., 1995³¹⁶). Although MSM who had undergone VCT reported more condom use and had more protected penetrative sexual acts than untested MSM, they also had a significantly greater number of sexual partners. Therefore, overall untested and tested MSM reported a similar number of unprotected sexual acts.

Declines in risky sexual behaviour, associated with VCT

Several early studies do, however, show significant decreases in risk behaviour associated with VCT, with seropositive men showing greater reduction in risk behaviour than seronegative men or men who are unaware of their HIV status. It is suggested that learning about being seropositive had a greater impact on changing behaviour and showed that seronegative men were still putting themselves at risk from infection.

In a study from Baltimore, United States 1 001 MSM were offered VCT (Fox et al., 1987³¹⁷). Of those, 670 elected to have VCT and 311 declined (the two groups had similar baseline characteristics). All were coun-selled about safer sex. In all groups unsafe sexual practices declined, although disclosure of a seronegative test result led to a significantly smaller decline in these sexual activities

In Boston, MSM who tested seropositive were more likely to have protective sexual behaviour than seoneg-ative or untested men (McCusker et al., 1988³¹⁸)

Three cohort studies (Cohn et al., 1988³¹⁹, Zones et al., 1986³²⁰, McKusick et al., 1990³²¹) and three cross-sectional studies also showed an association between VCT and reduction in risky sexual behaviour (Valdiserri et al., 1988³²², Frazer et al., 1988³²³, Ross 1988³²⁴).

Long-term studies, however, have shown that initial changes in sexual behaviour following VCT may be difficult to maintain. In a study from the United States, at two years 47% of people had “relapsed” (not used safer sex practices) at least once (Abid et al., 1991³²⁵).