Objective: To determine if an association exists in young men who have sex with men (MSM) between being under the influence of alcohol or drugs during sex and participation in sexual behaviors which increase the risk of human immunodeficiency virus (HIV).
Study Design: A total of 3492 young MSM were interviewed through the Young Men’s Survey, an anonymous, cross-sectional, multisite, venue-based survey conducted from 1994 through 1998 at 194 public venues frequented by MSM aged 15 to 22 years in 7 US cities.
Results: The majority of young MSM reported both receptive and insertive anal intercourse, and of these, approximately half reported not using condoms. Report of unprotected receptive anal intercourse at least once in the prior 6 months was associated with being under the influence of alcohol (adjusted odds ratio [AOR] = 1.5; 95% confidence interval [CI] = 1.2–1.8), cocaine (AOR = 1.6; 95% CI = 1.1–2.2), amphetamines (AOR = 1.5; 95% CI = 1.1–2.0) or marijuana during sex (AOR = 1.3; 95% CI = 1.1–1.6). Report of unprotected insertive anal intercourse at least once in the prior 6 months was associated with being under the influence of alcohol (AOR = 1.2; 95% CI = 1.0–1.5), cocaine (AOR = 1.5; 95% CI = 1.1–2.0) or amphetamines (AOR = 1.9; 95% CI = 1.4–2.6).
Conclusions: HIV prevention strategies for young MSM need to incorporate substance use risk reduction.
A large-scale survey of young men who have sex with men in 7 US cities found an association between reports of being under the influence of alcohol or certain illicit drugs during sex and unprotected insertive and receptive intercourse, which increases the likelihood of human immunodeficiency virus transmission.
From the *Department of Epidemiology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland; † Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia; ‡ Public Health–Seattle and King County, Seattle, Washington; § San Francisco Department of Public Health, San Francisco, California; ‖University of Texas, Southwestern Medical Center at Dallas, Dallas, Texas; ¶ Los Angeles County Department of Health, Los Angeles, California; #Florida Department of Health, Tallahassee, Florida; ** The New York Blood Center, New York, New York; and the †† New York City Department of Health, New York, New York. A complete listing of members of the Young Men’s Survey Study Group is provided below.
This study was funded by a cooperative agreement between the CDC and each participating site (Baltimore: 062/CCU20608-07; Dallas: U62/CCU606237; Los Angeles: U62/CCU906253-11; Miami: U62/CCU406219; New York: U62/CCU206208; San Francisco: U62/CCU906255; Seattle: U62/CCU0006260). We thank members of the Young Men’s Survey Study Group, who include: Atlanta, GA: Bradford N. Bartholow, MA, Robert S. Janssen, MD, John M. Karon, PhD, Duncan A. MacKellar, MA, MPH, Daniel H. Rosen, PhD, Gina Secura, MPH, and Linda A. Valleroy, PhD; Baltimore, MD: David D., Celentano, ScD, John B. Hylton, PhD, Frangiscos Sifakis, PhD, and Liza Solomon, DrPH; Dallas, TX: Anne C. Freeman, MSPH, Santiago Pedraza, Douglas A. Shehan, and Eugene G. Thompson, MS; Los Angeles, CA: Wesley L. Ford, MA, MPH, Bobby E. Gatson, Peter R. Kerndt, MD, MPH, and Susan Stoyanoff, MPH; Miami, FL: James A. Bay, PhD, John Kiriacon, MPH, Marlene LaLota, MPH, Thomas M. Liberti, and James M. Schultz, PhD; New York, NY: Vincent A. Guilin, BA, Beryl A. Koblin, PhD, and Lucia V. Torian, PhD; San Francisco, CA: Mitchell H. Katz, MD, Willi McFarland, MD, PhD, Guilliano N. Nieri, BA, and George F. Lemp, DrPH; Seattle, WA: Hanna Thiede, DVM, MPH, and Thomas E. Perdue, MPH. We also acknowledge the editorial assistance of Wendy W. Davis.
Ms. Stoyanoff is now with the Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California.
Correspondence: David D. Celentano, ScD, Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street (E-6008), Baltimore, MD 21205. E-mail: email@example.com.
Received for publication May 23, 2005, and accepted August 22, 2005.
SEXUAL RISK TAKING CAN BE profoundly influenced by a variety of factors. Two of these factors and their possible interaction are discussed in this paper. A chief situational factor for unprotected sexual intercourse is substance use or having sex under the influence of alcohol and drugs. One of the enduring findings in contemporary human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) research has been the association, especially in men who have sex with men (MSM), between unsafe sex and the use of alcohol and recreational drugs at the time of sexual intercourse.1–6
Another factor which influences sexual risk taking is age. Young gay and bisexual men born in the 1980s may not have experienced the profound effects of HIV on the gay community and were not exposed to HIV prevention campaigns focused on gay men. Indeed, Koblin et al.7 found in their sample of young MSM that subjects who expressed less concern with the seriousness of HIV infection were more likely to report 10 or more male partners in the previous 6 months than their more concerned peers. At the same time, high rates of unprotected anal intercourse (UAI) have been clearly documented among young MSM. Hays et al.8 found that 43% of MSM aged 18 to 25 years in midsized West Coast communities engaged in UAI in the prior 6 months, which is comparable to the 40% rate reported in Vancouver for MSM aged 18 to 30 years.9 Webster et al.10 found in their sample of young MSM in South Beach, FL, that 45% were engaging in UAI, whereas Dean and Meyer11 found that 37% of 18- to 24-year-old MSM in New York City participated in unprotected receptive anal intercourse. Other studies have shown an increase in the number of young MSM who are taking sexual risks. The San Francisco Young Men’s Health Study showed that the prevalence of UAI increased from 37% to 50% among a cohort of men aged 18 to 29 years between 1993 and 1997, half of whom reported that their partner was of unknown or discordant HIV status.12 Similarly, the San Francisco Stop AIDS Project showed an increase in UAI in young MSM from 32% in 1994 to 42% in 1997.13
Although both substance use and young age are correlated with taking sexual risks, there is little research on the association between alcohol and drug use in conjunction with sexual intercourse and sexual risk taking behavior in young MSM. Whereas studies have shown that 18% of young MSM report using drugs in their last sexual encounter14 and that a significant association exists in young MSM between “being high” and having UAI with a non–main partner,15 little is known about the extent to which sexual risk taking may be associated with being under the influence of different substances during sex. This report focuses on the association between being under the influence of alcohol or certain drugs during sex and unprotected sexual behavior in a large cross-sectional survey of 15- to 22-year-old MSM from cities across the United States. Understanding the influence of alcohol and/or drugs on sexual risk taking is a critical component of effective prevention efforts in this population.
Between 1994 and 1998, the Young Men’s Survey (YMS) was conducted in 7 cities in the United States following a common protocol16 to estimate the prevalence of HIV and risk behaviors among adolescent and young adult MSM. A venue-time strategy was used to sample the population because young MSM are difficult to reach through traditional household-sampling methods. The methods of YMS16,17 are briefly presented here.
YMS was conducted in Baltimore, MD; Dallas, TX; Los Angeles, CA; Miami, FL; New York, NY; the San Francisco Bay Area (San Francisco, Oakland, and San Jose, CA); and Seattle, WA. Young men were identified at public venues where young MSM gathered. The venues consisted of bars, dance clubs, businesses, social organizations, sex establishments, and neighborhood locations MSM frequented. In each city, we identified potential venues and time periods of high attendance through interviews with community informants, focus groups of young MSM, and systematic observation. Enumerations of young men were conducted at potential venues during high-attendance 4-hour time blocks (sampling periods) to construct monthly sampling frames. Venues and associated sampling periods were included in frames if the minimum number of eligible young men exceeded 6 in any 4-hour time period. Sampling frames were reviewed on a monthly basis, and venues were added or deleted, depending on this attendance criterion, as well as practical considerations (e.g., closings, safety). Each month, over 12 venues and associated time periods were randomly selected and scheduled for sampling in the upcoming month.
During each sampling event, staff counted all men who appeared to meet the study age criteria (15–22 years) as they entered a geographically designated area (e.g., an intersection, the entrance to a dance club). Young men were systematically approached and screened for eligibility. The study’s eligibility criteria were (a) being of the appropriate age group (i.e., between 15 and 22 years old), (b) residency in a defined geographic area, and (c) not having previously participated in the study. Eligible men who agreed to be interviewed were escorted to a van located nearby. After obtaining informed consent, an interviewer/counselor administered a standardized questionnaire, conducted HIV pretest counseling, obtained a blood specimen for HIV antibody testing, and provided referrals to medical and social services as needed. At the conclusion of the interview, participants were compensated $40 to $50 for their time and given appointments for HIV test results and posttest counseling 2 weeks later. Participants who could not complete the study at the time of recruitment were given interview appointments at an office within a few days.
Survey and blood test results were anonymous, linked only by a study identification number. We used HIV-1 antibody assays approved and licensed by the US Food and Drug Administration. The YMS protocol was approved by the institutional review boards of the Centers for Disease Control and Prevention and each participating study center.
To exclude duplicates, blood specimens of participants with the same date of birth and race were tested with the Miragen antibody-profile assay.18 Specimens with matching antibody profiles were considered to be duplicates. In such cases (n = 162), only data from the initial interview were used in our analyses.
The interviewer-administered survey included questions on demographics, frequency of attendance at selected venues, and sexual and drug behaviors in the past 6 months. Drug use was ascertained in the context of sex. Participants were asked whether they were ever under the influence of alcohol or a series of drugs during sex in the 6 months before the survey. These drugs included alcohol, marijuana, amphetamines and methylenedioxymethamphetamine (ecstasy), nitrites (“poppers”), cocaine, barbiturates, lysergic diethylamide (LSD), crack, and opiates. Unprotected sex was defined as not using condoms consistently during insertive or receptive anal sex or oral sex in the prior 6 months.
In this report, we restrict the statistical analysis to the 3492 young MSM who reported ever having sex with a man. In univariate analyses, we assessed associations between being under the influence of alcohol or drugs during sex in the last 6 months with receptive and insertive UAI and unprotected oral sex. Associations were assessed using χ2 statistics and calculation of odds ratios and their 95% confidence intervals (CIs). In multivariate analyses, we adjusted for city, race/ethnicity, age, number of male partners, and HIV serostatus of participants. We used multiple logistic regression to assess associations between our 3 outcomes (i.e., receptive UAI, insertive UAI, and unprotected oral sex) and each drug separately that was found to be significantly (P <0.05) associated with our outcomes in univariate analysis. In each separate analysis, we adjusted for city, age, race, number of male partners, and HIV serostatus. We report adjusted odds ratios (AOR) and 95% CI from the multiple logistic regression analyses. Homogeneity across cities between each of the 3 outcomes and their associated variables was assessed by the Breslow-Day test. Data from the 7 cities were pooled for insertive UAI and receptive UAI, due to observed homogeneity of associations. However, associations between marijuana use and unprotected oral sex varied significantly by city (P <0.05). Therefore, marijuana use was not assessed in its potential association with oral sex.
Of the original 38,522 men who appeared to be young and entered venue intercept areas during 1592 sampling events at 194 different venues in 7 cities, 3492 were ultimately enrolled in YMS.17 Thirty percent of participants were enrolled at street locations, 29% at dance clubs, 12% at bars, 10% at social organizations, 9% at businesses, 4% each at parks, bathhouses, or health clubs, and at other locations (e.g., beaches). Among eligible participants, more men enrolled at social organizations than other venues (79% versus 61%; P = 0.001), whereas fewer men enrolled at dance clubs than other venues (53% versus 66%; P = 0.001). Of the 3492 participants, 36% were white, 30% Hispanic, 17% black, 6% Asian, and 11% of mixed race/ethnicity or “other.” The ethnic composition varied by city (Table 1). Proportionally more Hispanics participated in Los Angeles, Miami, and New York, and proportionally more Asians participated in the San Francisco Bay Area and Seattle (Table 1). Proportionately more participants in Baltimore and New York were black, and proportionally more participants in Dallas and Seattle were white. Approximately one-half of respondents were 15 to 19 years of age. The overall HIV prevalence for study participants was 7.2% and ranged from a low of 2.2% in Seattle to a high of 12.1% in New York City.
Approximately equal proportions of MSM reported receptive and insertive anal intercourse (56.9% and 58.5%, respectively) in the 6 months before interview, with relatively little variation by city (Table 1). Oral intercourse was very common (88% overall), and 23.1% of participants reported 5 or more male partners in the prior 6 months, again with little city variation.
Alcohol use was commonly reported: approximately 43% of men reported being under the influence of alcohol during sex (Table 1). Marijuana was the most commonly used recreational drug (28.2%), ranging from 19.1% in Dallas to 38.2% in New York City. Amphetamine use was reported by 9.2% of participants, with infrequent use in New York City and more common use in Los Angeles, the San Francisco Bay Area, and Seattle. Cocaine use (8.7%) was most often reported in Miami (14.5%) and least often in the San Francisco Bay Area (5%). Use of poppers (8%) and ecstasy (7%) also showed regional variation, with poppers ranging from 3.2% in Baltimore to 12.6% in Seattle and ecstasy use ranging from 3.7% in Los Angeles and San Francisco to 12.2% in Dallas. Finally, use of crack cocaine and heroin was rarely reported in this sample.
Table 2a, b, and c presents the univariate and multivariate analyses of alcohol and drug use and sexual behavior. Table 2a presents the findings for substance use and receptive UAI. Of 1987 young MSM who gave a history of receptive anal intercourse in the prior 6 months, 53.6% reported that their partner did not always use a condom during receptive anal sex. Alcohol use before sex was associated with engaging in receptive UAI in univariate analysis (Table 2a). After adjusting for age, race, city, number of male partners, and HIV serostatus of the respondent, alcohol use remained a significant cofactor for receptive UAI. Among drugs examined, cocaine, poppers, amphetamines, and marijuana were each associated with increased odds of receptive UAI, and each (with the exception of poppers) maintained statistical significance in multivariate logistic regression (Table 2a). No increased risk was seen for ecstasy use or other rarely used drugs (barbiturates, LSD, crack cocaine, and heroin).
Of 2044 young MSM who reported insertive anal intercourse in the prior 6 months, 51% reported that they did not always use a condom during insertive anal sex. Men who reported drinking alcohol before sex were more likely to give a history of insertive UAI (Table 2b). After adjustment for demographics, number of male partners, and HIV serostatus, the magnitude of the association diminished, although it maintained marginal statistical significance. Among the drugs examined, amphetamine use was most strongly associated with insertive UAI. Other drugs associated with an increased risk of insertive UAI included cocaine, poppers, and ecstasy. In multivariate analysis (Table 2b), the association for an increased risk of insertive UAI was maintained for amphetamines and cocaine, whereas the effect of ecstasy and poppers was no longer statistically significant. No association was seen for unprotected insertive anal intercourse for marijuana use or “other” drugs in univariate or multivariate analysis.
Oral sex was reported by 3074 participants, almost all of whom (93.8%) reported not always using a condom during oral sex. Alcohol use before sex was associated with a significant risk of unprotected oral sex in univariate analysis (Table 2c) but was marginally associated with unprotected oral sex in multivariate analysis (Table 2c). Although a few drugs attained marginal significance for unprotected oral sex in univariate analysis, none retained significance after adjustment for age, race/ethnicity, city, number of male partners, or HIV serostatus.
A large proportion of our sample of young MSM in seven cities in the USA engaged in high-risk sexual practices that placed them at increased risk for acquiring HIV infection. Over half the participants recently had either insertive or receptive anal intercourse, and, of these, half did not consistently use condoms. Being under the influence of alcohol, marijuana, amphetamines or cocaine during sex was significantly associated in adjusted analysis with UAI. Our results concur with other large scale studies which show an association between substance use and UAI in younger15 and older MSM.19 At the same time, our study offers a unique profile of the risks associated with specific drugs. Young MSM should be cautioned not only about the increased risk of UAI, which is associated with alcohol and substance use, but also about the specific risks posed by certain drugs.
Use of alcohol and drugs may influence risky sexual behavior in young MSM in a number of different ways. Adolescents and young adults coming to terms with their sexual identity may use alcohol or other substances to cope with concerns about the implications of feeling attracted to same-sex individuals. Frequent binge drinking has been found to be significantly associated with same sex-attraction in adolescents,20 and gay, lesbian, and bisexual (GLB) youth are significantly more likely than their heterosexual peers to report lifetime and recent (past 30 days) substance use.21 At the same time, young MSM in the YMS who identified themselves as heterosexual or bisexual were more likely to use drugs at least once a week than young MSM who identified themselves as homosexual.22 For adolescents and young adult MSM who are still in the process of defining their sexual identities (two-thirds of the participants in YMS reported having had sex with both men and women17), alcohol and substance use may ease reservations about participating in certain sexual behaviors. Blake et al.21 found that GLB youth were more likely to report the use of alcohol or drugs before sex than their heterosexual peers, whereas McKirnan et al.23 observed that MSM who report using substances to help them escape awareness of HIV risk were more likely to participate in unprotected receptive anal intercourse.
The use of alcohol may also influence condom use. Alcohol disinhibition has been raised as a factor in lack of condom use, especially among youth.24 Alcohol may reduce the efficiency of decision making in that proximal cues such as sexual arousal are processed, whereas more distal cues such as HIV-prevention messages are ignored.25
Further, even though most participants were not of legal drinking age, the venues (i.e., bars and dance clubs) in which they congregate and which they may use to find casual partners are often associated with drinking. In MSM, alcohol use is strongly correlated with taking sexual risks.19,26,27 Greenwood et al.28 found a positive correlation between alcohol use and both frequent gay bar attendance and multiple sex partners. Seage et al.3 reported that MSM who ranged in age from 20 to 26 were significantly more likely to have UAI with a nonsteady partner after drinking and using drugs. Given that most MSM are not aware of the serostatus of their nonsteady partners,19 UAI in this situation is particularly risky. Thiede et al.,22 finding that young MSM who identified themselves as being “out” reported greater drug use, suggest that these young MSM are integrating themselves into urban gay culture, a lifestyle which typically involves settings in which drug and alcohol use are common.
“Recreational” drugs are associated with other specific risks. Amphetamine and cocaine use are correlated with cognitive impairment.29 Methamphetamine use is strongly associated with high-risk sexual behaviors in MSM,6 has become a central feature of sex clubs and “circuit” parties,30 and is frequently associated with polydrug use.31 Heavy methamphetamine polydrug users tend to be younger and engage in more unprotected sex with partners of unknown or serodiscordant status.31 MSM who use cocaine have more frequent anal intercourse and are less likely to be receptive to safer-sex messages.32 In our study, whereas only 8% of the YMS participants gave a history of cocaine use during sex, it remained a significant risk for unprotected sex after adjustment for known risk factors in multivariate analysis.
There are potential limitations which must be considered in drawing inferences from our findings. First, there was some nonparticipation bias associated with race/ethnicity and age. Asian Americans were less likely to participate and MSM of mixed race were more likely to participate in our study.17 Also, younger men were more likely to participate than older men. However, the relatively small proportion of Asian Americans and mixed-ethnicity participants and nearly equal numbers of men in both younger (15–19) and older (20–22) age groups probably do not overly affect the study associations. In all analyses, we adjusted the associations between substance use and demographic factors.
Second, sampling bias may play a minor role in drawing inferences from our findings. Many of our subjects were identified at bars, dance clubs, and other sites where substance and alcohol use, as well as risky sexual behaviors, can occur and may be more likely than in other settings. However, unpublished data from the San Francisco Young Men’s Health Study, a population-based household survey which showed that 91% of 18- to 23-year-old MSM had been to a “gay” bar in the past 6 months, have been cited17,33 as evidence that young MSM attending gay bars are a reasonably representative population of young MSM overall. Further, over half of the men enrolled in YMS were recruited in venues other than bars and dance clubs.
Third, factors which are unique to the individual or the situation may affect both substance use and sexual risk. An underlying personality trait, such as sensation seeking, may make both sexual risk taking and substance use more likely. Li et al.34 found this to be the case in their longitudinal study of young adolescents, whereas higher sensation-seeking scores in MSM35,36 have been correlated with both substance use and UAI. Partner type may also affect sexual risk-taking behavior. Rusch et al.37 found that in young MSM, partner type affected how different substances were used in different sexual situations.
Finally, this study, like any which measures self-reported behaviors, confronts an inevitable obstacle in suggesting a relationship between substance use and risky sexual behavior. Individuals may not always recall events correctly, especially events involving substance use. Cross-sectional studies are generally more likely to find an association between substance use and sexual risk behavior than event-level research and are often regarded as less reliable than episode-level research.2 There are, however, episode-level studies which have observed a significant association between substance use and UAI.38 Furthermore, the strength of associations observed in this study suggests that substance use in connection with sexual behavior presents a risk to young MSM that should not be ignored.
Results from this study reveal the environment of risk which can surround the sexual behavior of young MSM. More than half of the young MSM in our sample participated in unprotected receptive and insertive anal intercourse, whereas nearly all young MSM in our sample reported unprotected oral sex. At the same time, being under the influence of alcohol or marijuana during sex was common, and we found both to be associated with unprotected receptive anal intercourse, clearly the riskiest sexual practice for HIV acquisition. Although being under the influence of amphetamines or cocaine during sex was less common among our respondents, it was also significantly associated with UAI, both receptive and insertive. Clearly, prevention aimed at young MSM must reflect these realities. It has been suggested that the socialization process for young MSM involves both initiation into sexual practices as well as into substance use.39 Successful HIV prevention must consider the demands of these processes as well.
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