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

2. Situational association studies examine the frequency of high-risk
sexual behaviors and also examine the extent to which sexual
activities occur in conjunction with NMPD use. These studies
establish the occurrence of high-risk sex and of sex while using drugs
or alcohol, but do not determine if high-risk sex is more likely to
occur when drugs or alcohol are used.
3. Event analysis studies examine sexual behaviors and NMPD use in
specific sexual encounters. While these studies can assess the
temporal association of high-risk sexual behaviors and drug or
alcohol use, they share the limitations in terms of causal inference of
the other two categories of studies. Yet, event analysis studies are
useful in distinguishing circumstantial within-person associations.
None of the seven event analysis studies involving gay/bisexual men
cited by Leigh and Stall demonstrated a significant difference in the
likelihood of risky sex when NMPDs were used, and only one study
found an association between drinking and UAI (McCusker et al. 1990).
The most recently published event analysis studies of gay/bisexual men,
from the multisite Project Sigma of Great Britain (Weatherbum et al.
1993) and the Talking Sex Project of Toronto (Myers et al. 1992), also
failed to detect any differences in the incidence of unprotected receptive
or insertive anal intercourse between events involving the use or nonuse
of alcohol or NMPDs, respectively. The general failure of event analysis
studies to confirm a link between NMPD use in specific sexual
encounters and risky sexual behaviors does argue for possible underlying
interpersonal personality or character factors, rather than circumstantial
factors, as underlying the NMPD-risky sex associations documented
below.
MECHANISMS AND THEORIES OF ASSOCIATIONS BETWEEN
NMPD USE AND HIGH-RISK SEXUAL BEHAVIOR AMONG
GAY/BISEXUAL MEN
Leigh and Stall conclude that “it is clear that there is a positive
relationship between substance use and high risk sex; what is less clear is
the level at which this link exists.... findings from these studies are
consistent with a number of explanations-causal, correlational, and
confounding” (p. 1038). To the extent that any specific underlying
mechanisms have important HIV prevention implications, they need to be
considered as priorities for future research efforts. It is important to keep
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