The Context of HIV Risk Among Drug Users and Their Sexual Partners

eported lapses to unsafe RAS among men in the Chicago MACS/CCS
cohort, it does indicate that at least a portion of relapses to unsafe sex
occurs in conjunction with the return to use of a specific NMPD
historically associated with RAS among gay men (Mayer 1983). These
lapses, in turn, may be associated with a significant proportion of new
HIV infections given the high likelihood that the insertive partner is
already infected, and the possible facilitation of infection when poppers
are used during RAS.
Association of NMPD Use with Sexual Partners and Changes in
High-Risk Sex and Incidence of HIV Infection, Including Within-
Subject Event Analysis Studies. None of the three prospective cohort
studies summarized here employed a within-subject comparison of events
that involved or did not involve specific NMPD use. However, the
Toronto Sexual Contact Study recently published data showing that only
NMPD use with sexual partners, in contrast to NMPD use outside sexual
encounters, was associated with increased scores on a sexual risk index
that summarized all reported sexual encounters (Calzavara et al. 1993).
However, less than 10 percent of reported substance use in this cohort
was not associated with sexual encounters. In multivariate analyses, only
the use of poppers, marijuana, or alcohol during sexual encounters were
significantly associated with higher sexual risk scores. When their study
participants were asked whether drugs or alcohol had an effect on their
sexual behavior, 45 percent said “yes,” and the majority of those
respondents reported that they were more likely to have more partners,
more likely to have casual partners, and less likely to use condoms. In
the Chicago MACS/CCS cohort (Ostrow et al. 1993), incident
seroconversion was associated with popper and cocaine use, although
specific use of those NMPDs with sexual partners was not separately
examined.
Intervention Data Which Simultaneously Assesses Changes in
NMPD Use and HIV Risk-Taking. While studies that simultaneously
assessed the effects of behavioral interventions on both substance use and
HIV risk-taking behaviors might provide the most persuasive evidence
for a direct causal link between NMPD use and sexual behavior change
among men at risk of HIV infection, such data are essentially nonexistent.
However, the Chicago MACS/CCS series of studies examined behavioral
and psychosocial correlates of changes in popper use (Ostrow et al.
1991). Men remitting from popper use were at significantly lower anal
sexual risk levels, more likely to have participated in individual
psychotherapy, and more likely to report higher levels of social
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