Clinical Textbook of Addictive Disorders 3rd ed - R. Frances, S. Miller, A. Mack (Guilford, 2005) WW

19. HIV/AIDS and Substance Use Disorders 415SUBSTANCE USE AND RISK OF HIV INFECTIONA variety of exposure and host factors influence seroconversion and diseaseprogression. These may include altered baseline host immune capacity and viralload in the seropositive person. The presence of host-concurrent infections,most notably viral (Herpes simplex, cytomegalovirus, the hepatitides) and bacterialinfections in the bloodstream (endocarditis, others), may contribute toaltered immunity. In the case of skin or mucosal ulcerations or inflammationfrom repeated injection sites or sexually transmitted diseases, breaches canafford easy entry of microorganisms. Clearly, some practices in drug use and sexualbehavior carry more risk than others for disease transmission. In general,infections have increased prevalence in substance-using populations, and sincesubstance users often do not restrict their use to a single drug, some risk effectsmay be synergistic.Heroin use by injection is a key element in the progression of the HIV epidemic.IDUs, as well as other substance abusers, have further increased risk dueto social and sexual contact with other high-risk individuals. Use of otheragents contributes substantially to behavioral risk through disinhibiting effectson the primary modes of transmission: sexual contact and injecting druguse (Booth, Kwiatkowski, & Chitwood, 2000; Woods et al., 1996). Stall,McKusick, Wiley, Coates, and Ostrow (1986) found that homosexual men withhigh-risk sexual behaviors were at least twice as likely to use drugs during sexualencounters as men considered at low risk for HIV exposure. Stimulant users,particularly, crack cocaine smokers and injecting stimulant users (cocaine,amphetamine), incur considerable risk for HIV. Cocaine injectors inject morefrequently to maintain a quickly decaying “high.” As with other disinhibitingdrugs, users are apt to engage in risky sexual behavior fueled by these drugs’stimulant properties. Consistent with an earlier report, Seidman, Sterk-Elifson,and Aral (1994), in a national study of 27,000 current drug users, found thatsexual risk behaviors for HIV transmission were significantly higher in crackcocaine smokers and crack-smoking IDUs than in nonsmoking IDUs, and thatthe alarmingly low rate of condom use (< 20%) was additionally associatedwith concurrent alcohol use (Booth et al., 2000). Female substance abusersare at particular risk for transmission through sexual risk behaviors (Booth,Koester, & Pinto, 1995), which include turning to commercial sex work as aprimary means of support. The use of crack cocaine is a strong predictor of riskysexual behaviors among women (Hoffman, Klein, Eber, & Crosby, 2000). Alcoholabuse has been increasingly recognized as a major cofactor in HIV transmissionrisk. Higher alcohol consumption in homosexual and bisexual men hasbeen associated with increased HIV seroconversion (Penkower et al., 1991)and NIDU ambulatory alcoholics had higher than expected HIV seroprevalencerates associated with more risky sexual behaviors (Avins et al., 1994).