Risk for HIV/Sexually Transmitted Disease and the Influence of Alcohol Consumption among Young Methamphetamine Users in Northern Thailand

Transcription

1 Risk for HIV/Sexually Transmitted Disease and the Influence of Alcohol Consumption among Young Methamphetamine Users in Northern Thailand By: Rajesh Panjabi, MPH Candidate Capstone Advisor: Dr. David Celentano Department of Epidemiology Bloomberg School of Public Health Johns Hopkins University May 3 rd, 2006

2 Abstract Context: Worldwide, it is estimated that 38 million people abuse amphetamine-type stimulants. Widespread methamphetamine (MA) abuse, particularly among youth, is a major public health problem in Thailand. There is limited research on the intersection between MA use and sexually transmitted diseases (STD). Additionally, there is limited knowledge of the combined effects of alcohol and MA on STDs and sexual risk taking behaviors in this setting. Objective: To investigate risks for STD among young MA users in northern Thailand and to understand whether these risk factors vary by different patterns of alcohol consumption. Design: Cross-sectional survey with biological sample collection of six STDs (HIV-1, syphillis, Neisseria Gonorrhoeae, Chlamydia Trachomatis, Herpes Simplex Virus-2 and Trichomonas Vaginalis). Setting: Chiang Mai Province, northern Thailand. Participants: Young (ages years) active using index MA users and members of their drug and sexual networks (N=552) who were participants in a randomized behavioral intervention. Main outcome measures: Prevalence and risk factors for STDs for overall sample and by frequency of alcohol consumption. Analysis: Univariate and multivariate logistic regression to determine unadjusted and adjusted odds ratios for putative risk factor for any STD for the overall sample and by different patterns of alcohol consumption. Results: Overall, 35.5% of participants were age 20 or older, with age ranging from 18 to 25 years, 401 (75.7%) were male, with 208 (39.3%) currently enrolled in school. The prevalence for any STD, any ulcerative STD (HSV-2 or syphilis) and HIV were 29.6%, 7.4% and 1.06%, respectively. Among all MA users, independent risk factors for prevalent STD were age 20 years or older (OR, 1.56 for age 20 vs. age < 20; 95% CI, ), more lifetime sexual partners (OR, 3.94 for 2-7 vs. 1 lifetime sexual partner; 95% CI, ; OR, 7.6 for 8 vs. 1 lifetime sexual partner; 95% CI, ), and frequent MA use (OR, 1.9 for MA use 4 times weekly vs. MA use < 4 times weekly; 95% CI, ). STD risk factors, including drug and sexual risk profiles, differed by frequency of alcohol consumption. Compared to infrequent alcohol consumers, those who consumed alcohol frequently were older (p=0.001), more likely to be male (p=0.002), used MA more frequently in the past month (p=0.038), and had a higher number of lifetime sexual partners (p=0.0002). Among infrequent alcohol consumers age 20 years or older (OR, 1.98 for age 20 vs. age < 20; 95% CI, ) and more lifetime sexual partners (OR, 2.79 for 8 vs. 1 lifetime sexual partner; 95% CI, ) were predictive of STD. Among frequent alcohol consumers, STD was independently associated with more lifetime partners (OR, 1.76 for 8 vs. 1 lifetime sexual partner; 95% CI, ). Conclusions: A high prevalence of STD and associated drug and sexual risk factors among young, active MA users in Northern Thailand was observed with higher sexual and drug risk profiles among those using alcohol frequently. Integrated, social network-based risk reduction programs targeting MA drug and alcohol dependence as well as HIV/STD transmission among young MA users should be developed.

3 Introduction Worldwide, it is estimated that 38 million people abuse amphetamine-type stimulants 1. Nearly 60 percent of consumers of ATS, including methamphetamine (MA), live in east and Southeast Asia 1. Several political and economic factors affect the spread of MA use in the region. The increasing availability of ATS precursor chemicals, pervasive production facilities based primarily in Burma, and clandestine trafficking networks are particularly salient perpetuating influences 1-3. In northern Thailand, MA abuse disproportionately affects adolescents and young adults, among whom recent reports estimate MA use of over 40% by male and 19% by female students 4. Widespread MA abuse, particularly among youth, is a serious public health problem in Thailand, but its relevance to epidemics of sexually transmitted diseases (STDs) and HIV remains unclear. Known as Ya Ba, or crazy medicine in Thai, long-term and regular MA use can lead to loss of control and compulsive behavior 5. Persistent use can cause irritability, aggressiveness and hallucinations 5. While less studied, associations between MA use and risky sexual behavior have also been documented 6. For example, Beyrer et al. (2003) found that MA users in Northern Thailand had higher sexual risk profiles for HIV than general population estimates of Thai youth 7. The MA epidemic in Thailand has the potential to propagate the spread of STD and HIV, particularly among young marginalized populations, diminishing national prior successes in HIV prevention. Understanding STD risk among MA users may be further complicated by polydrug use, another area about which little is known in northern Thailand. Clustering of alcohol use and

4 MA abuse has been observed among youth and adolescents elsewhere. For instance, Wu et al. found young American alcohol abusers to be 29 times as likely as nonusers of alcohol to use multiple club drugs, including MA 8. A survey of middle school students in New York showed that alcohol use was highly predictive of MA use 9. Dual alcohol abuse among MA users may be especially pertinent to their HIV and STD risk since the literature supports an independent association between alcohol consumption and sexually transmitted diseases 10,11. The current study aims to further investigate risks for STD among young MA users in northern Thailand and seeks to understand whether these risk factors vary by different patterns of alcohol consumption. Methods Study Population Between April 18, 2005 and January 10, 2006, 552 young MA users living in Chiang Mai Province, Thailand and members of their sexual and drug use networks were actively recruited for the study. Data for this cross-sectional study were obtained from a survey and biological specimens collected at baseline as part of an ongoing randomized behavioral intervention trial. Briefly, the trial aims to assess the effectiveness of peer education and HIV voluntary counseling and testing (VCT) versus HIV VCT alone in reducing drug use and sexual risk behavior as well as incident STD and HIV among active MA users and members of their drug and sexual networks.

5 The MA using index participants and their network members were recruited from three sources. The participants were recruited from a cohort of over 500 active MA users in follow-up in another study described in detail elsewhere 12 ; from MA users in the community; and through snowball sampling. Index participants were recruited if they: (1) could provide written informed consent; (2) used MA at least three times in the past three months; 3) had sex at least three times in the past three months; 4) could bring in sex or drug network members identified in the baseline interview, and (4) were willing to provide prevention outreach education to network members; and (5) were 18 years of age or older. Index participants were excluded if they were: (1) unwilling to provide locator information; (2) unable to participate in the group due to psychological disturbance, cognitive impairment, or threatening behavior; or (3) concurrently enrolled in another HIV or drug use intervention study. Network members were recruited if they could (1) provide written informed consent; (2) were named by index participant as a network member; (3) were 18 years of age or old. Network members were excluded if they were unwilling to provide locator information or displayed psychological or cognitive impairment. Data Collection Survey Instrument

6 Overall, 552 active MA using index participants and their drug and sexual network members were eligible for and enrolled in the study. After obtaining informed consent, behavioral and biological data were obtained. Baseline surveys were administered by trained interviewers and lasted roughly one hour. The questionnaire was based on extensive formative, ethnographic research as well as questions previously used in our research with drug users in Thailand 12. The instrument ascertained: demographic information including age, sex, educational level and current occupation; recent drug use history, such as types and progression of drugs used during the past three months, drugs used and their modes of administration, injection practices, procurement of needles and other injection equipment and drugs, needle hygiene and needle sharing practices, typical patterns of and behaviors during drug use (in particular, use of drugs in groups and locations of drug use) and changes in drug practices; and sexual practices, including lifetime and recent partners, including men and women, specific sexual acts with each type of partner (vaginal, anal and oral intercourse), condom use with each type of partner, frequency of visits to sex workers (both male and female) recently as well as reported condom use at those occasions, and experience as a sex worker or trading sex for money, drugs or survival (shelter, food, protection). STD Serology Serum samples were obtained by trained nurses and tested for six STDs (HIV-1, Syphillis, Neisseria Gonorrhoeae, Chlamydia Trachomatis, Herpes Simplex Virus-2 and Trichomonas vaginalis). Laboratory facilities met all CLIA certifications. Participants provided a serum specimen that was tested for HIV antibody by enzyme-linked immunosorbent assay (ELISA) using licensed commercially available reagents (Vironostica HIV Uni-form II plus 0, Organon Teknika).

7 Reactive ELISA specimens were tested with gel-particle agglutination (GPA) test for antibodies to HIV, (Serodia-HIV, Fujirebio Inc. Japan). Specimens tested positive in both antibody tests were considered HIV-positive. GPA-non-reactive specimens were confirmed by Western blot using licensed commercially available reagents (HIV Blot 2.2, Genelabs Diagnostics, Singapore). Syphilis antibodies were detected by a rapid plasma regain (RPR) (SyphScreen, Shield Diagnostics, UK), and reactive specimens were confirmed by a Serodia- TP-PA (Passive Particle Agglutination Test for Detection of Antibodies to Treponema pallidum, Funirebio Inc. Japan). Chlamydia and gonorrhoea were detected using the polymerase chain reaction method (Amplicor PCR Diagnostics, Roche Diagnostics Systems, Inc.). HSV-2 type-specific antibody assays were performed with a commercially available indirect enzyme-linked immunosorbent assay (ELISA) IgG assay (HerpesSelect; Focus Diagnostics [formerly known as Focus Technologies], Cypress, CA). The diagnosis of Trichomonas Vaginalis was made using the InPouch culture system. InPouch specimens were read within 15 minutes of collection and then 2 more times in a 5-day period. Specimens were incubated at 37 C in the interim. All patients received pre- and posttest counseling for HIV and other STDs and were offered treatment of STIs according to guidelines from the World Health Organization 13. Measures The dependent variable of interest, any STD, was defined as testing positive for any of the six aforementioned STDs at the time of the study. The key independent measure was frequency of alcohol consumption. Participants were considered infrequent alcohol

8 consumers if they drank alcohol 3 days/week in the previous month and frequent alcohol consumers if they drank alcohol 4 days/week in the previous month. Frequency of alcohol consumption was used as a proxy measure for levels of alcohol abuse. To check this assumption, the proportion of those testing positive for alcoholism by the CAGE questionnaire, a well-established clinical tool for assessing problem drinking, were calculated for infrequent and frequent alcohol consumers 14,15. Based on these criteria, participants had confirmed alcoholism if they responded yes to at least three of the following four questions: 1) Have you ever felt you should cut down on your drinking?; 2) Have people annoyed you by criticizing your drinking?; 3) Have you ever felt bad or guilty about your drinking?; 4) Have you ever drunk alcohol first thing in the morning to steady your nerves or to get rid of hangover? Statistical Analysis Of the enrolled 552 participants, those who had never used MA (n = 12) and whose last use of MA was at least 3 months prior (n = 10) were deleted, yielding 530 active MA users for analysis. Demographic, drug use, sexual behavior characteristics and STD prevalence were compared by frequency of alcohol consumption using Pearson s chi-squared tests and Fisher s exact test for categorical variables and t-test for equality of means for continuous variables. Univariate and multivariate logistic regression techniques were used to determine unadjusted and adjusted odds ratios with 95% confidence intervals for correlates of any STD separately for infrequent and frequent alcohol consumers. For multivariate modeling, age, sex, age at first sexual intercourse, condom use in past 30 days, lifetime sexual partners,

9 current school enrollment, whether MA use affected sexual desire and frequency of MA use were initially included and analyzed using a step-wise backward logistic regression analysis. Finally, a multiple logistic regression analysis was conducted on the entire sample, to determine independent risk factors for STD. Statistical Analysis was performed using STATA version 9.0 (College Station, TX). Results Demographic, Drug Use and Sexual Behavior Characteristics of Study Population Table 1 displays the sample (N=530) demographic characteristics, drug use patterns, and sexual risk behaviors. Overall, 188 (35.5%) were age 20 or older, with age ranging from 18 to 25 years, 401 (75.7%) were male, 429 (80.9%) had not completed high school, with 208 (39.3%) currently enrolled in school. Participants reported initiating MA use at a mean age of 15 (SD = 1.9), with 72 (13.6%) using MA four times or more per week in the prior month. Someone else had usually bought MA or gave it freely to the participant, at 51.1% and 16.8%, respectively. MA was purchased by the participant or obtained through dealing drugs for 29.1% and 3.0% of the study population, respectively. By CAGE questionnaire criteria, 252 (48.0%) had confirmed alcoholism. Characteristics related to the drug economy are also recorded. Of the sample, 270 (50.9%) had ever sold MA, 243 (45.9%) had been paid from delivering drugs. Of the 209

10 (data missing for n=321) responding about incarceration history, 139 (65.1%) responded affirmatively. Participants reported high levels of sexual activity. Virtually all respondents (99.6%) had ever had sexual intercourse, with mean age at first sexual intercourse at 15.5 years (SD = 1.7), and 488 (92.1%) had had casual sex in the prior 12 months. The mean number of lifetime sexual partners was 12.6 (SD = 16.3) with a wide range of 1 to over 95 (data missing for n=2). Over 45% (241) had 8 or more lifetime sexual partners. Of the 530 MA users, 457 (86.2%) had sex in the prior 30 days, with 90 (19.7%) of these always using condoms during sex in this period. For 350 (66%) MA users, drinking was a usual activity after MA use. For 302 (57%) MA users, sex was a usual activity after MA use. Additionally, 182 (24.7%) reported that MA use increased their sexual desire in the prior 3 months. Finally, the number testing positive for any STD was 157 (29.6%), any ulcerative STD (HSV-2 or syphilis) was 39 (7.4%) and HIV (n=470) was 5 (1.06%) [data not shown]. Characteristics of MA Users who Consume Alcohol Frequently vs. Infrequently Overall, 271 (51.1%) of participants consumed alcohol frequently ( 4 days/wk). Compared to infrequent alcohol consumers, those who consumed alcohol frequently were older (p=0.001), more likely to be male (p=0.002), and less likely to be currently in school (p=0.017). Differences in drug use patterns also existed. Frequent alcohol users started using

11 MA at an earlier age (p=0.003), used MA more frequently in the past month (p=0.038), and more likely to show symptoms of dependence (p=0.000) than MA users who consumed alcohol infrequently. With respect to sexual behavior, frequent alcohol consumers started having sex earlier (p=0.005), had higher numbers of lifetime sexual partners (p=0.0002), and more usually drank (p=0.000) and had sex (p=0.01) after MA use than those drinking alcohol infrequently. Frequent alcohol users were also more likely to participate in the drug economy, with higher rates of ever selling MA (p=0.000), ever being paid from delivering drugs (p=0.01) and lifetime incarceration (p=0.001) than infrequent alcohol users. Finally, frequent alcohol users had higher rates of any STD (p=0.000) and ulcerative STD (p=0.044). Correlates of STD by Frequency of Alcohol Consumption and Overall Table 2 displays unadjusted and adjusted risk factors for STD among infrequent alcohol consumers. In univariate analysis, among infrequent alcohol users, a higher prevalence of STD was associated with age 20 years or older, using MA four or more times weekly in the prior month, less than always condom use in the past month, sex being a usual activity after MA, and more lifetime sexual partners. Table 3 displays unadjusted and adjusted risk factors for STD among frequent alcohol consumers. Among frequent consumers of alcohol, a higher STD prevalence was associated with being female and sex being a usual activity after MA. In multivariate analysis, independent risk factors for STD among infrequent alcohol consumers were age 20 years or older versus less than age 20 years (Adjusted Odds Ratio [AOR], 1.98 for age 20 vs. age < 20; 95% Confidence Intervals (CI), ) and having

12 eight or more lifetime sexual partners versus one sexual partner (AOR, 2.79 for eight or more vs. one lifetime sexual partner; 95% CI, ). Always using condoms versus less than always during sex in the prior month was independently associated with protection against STD (AOR, 0.34; 95% CI, ) among infrequent alcohol consumers. Among frequent alcohol consumers, multivariate analysis showed STD to be independently associated with having eight or more lifetime sexual partners versus one sexual partner (OR, 1.76; 95% CI, ). Being male versus female yielded an independent protective effect against STD (OR, 0.37; 95% CI, ) among frequent alcohol consumers. Finally, independent risk factors for prevalent STD among all MA users, regardless of alcohol consumption frequency are displayed in Table 4. Among all MA users, independent risk factors for STD were age 20 years or older versus less than age 20 years (AOR, 1.56; 95% CI, ), having between two to seven versus one lifetime sexual partner (AOR, 3.94; 95% CI, ), having eight or more versus one lifetime sexual partner (AOR, 7.6; 95% CI, ), and using MA four or more times versus less than four times weekly in prior month (AOR, 1.9; 95% CI, ). Being male versus female (AOR, 0.48; 95% CI, ) and always using condoms versus less than always during sex in prior month (AOR, 0.52; 95% CI, ) were independently protective against STD among all MA users. Discussion

13 The current study found a high prevalence of STD among young active MA users and members of their drug and sexual networks in northern Thailand. High sexual risk profiles may help explain this finding. Indeed, the strongest independent predictor of STD in this population was having more lifetime sexual partners. We observed strikingly high levels and early onset of sexual activity among this group of drug users, with less than 20% reporting consistent recent condom use. Additionally, for most, sex was a usual activity after MA use. These findings suggest, as other studies have, that MA use is associated with increased sexual activity 6. Despite a low HIV prevalence (1.06%) for a population of drug users in Thailand, the observed high sexual risk profiles give cause for concern about an HIV and STD epidemic among this group. Should these young, highly sexually active networks of MA users ever become consistently exposed to populations with higher HIV and STD prevalence, then the spread of HIV and other STDs could rapidly expand. Thus, social network-based harm reduction interventions targeted at reducing drug use and STD risk throughout may be best placed to preclude an explosive transmission of HIV and STDs among this group. Such community-based interventions have been effective at reaching marginalized drug using populations at high risk for STDs and HIV in a variety of social and cultural contexts These results also have important implications for drug rehabilitation and HIV/STD prevention programs. Overall, frequent MA use was found to be highly associated with STD risk (Table 4), with those using MA four or more times weekly being 1.9 times more likely than those who use MA less than four times weekly. These findings further suggest that high MA use is detrimental not only for mental health, but also for protecting against sexually transmitted disease. Effective, long-term treatment of MA dependence could thus yield

14 benefits for mental health and potentially the reduction of STD transmission among frequent MA users. Unfortunately, such treatment does not exist. However, even before effective MA drug treatment becomes available, drug rehabilitation centers caring for MA dependents can take action to reduce the risk of STD among this population by incorporating STD prevention programming into drug treatment. Likewise, programs primarily concerned with preventing STD and HIV among frequent MA users should incorporate efforts to reduce MA dependence. Programs and policies that dually promote MA dependence rehabilitation and STD prevention may be effective, as they have been elsewhere, at reducing STD and HIV risk among young, active MA using populations in Thailand Schools, which nearly 40% of these MA users currently attend, may be an appropriate setting in which to develop such comprehensive programming. We also found segregation on demographic, drug use and sexual behavior patterns as well as STD risks among this group by level of alcohol consumption. MA users who frequently used alcohol were different demographically and engaged in more extreme drug use and risky sexual behavior than infrequent users of alcohol (Table 1). Compared to infrequent alcohol users, frequent alcohol consumers in this MA using group can largely be characterized as being older and more male with higher levels of MA abuse and more lifetime sexual partners. This affirms observations from other reports that indicate clustering of alcohol abuse among MA using populations 8,9. Overall, it is also apparent that frequent alcohol users had a higher STD prevalence, though this difference was not significant after adjustment for age, sex, recent condom use, frequency of MA use and lifetime sexual partners. In multivariate analysis, differences in independent STD predictors by frequency of alcohol consumption existed (Table 2-3), but a greater number of lifetime sexual partners was most

15 strongly predictive of STD in both groups. These findings suggest that while MA users who frequently use alcohol may not have significantly higher STD rates, they do have a more risky drug use and sexual behavior profile than those who use alcohol less frequently. Thus, MA dependence treatment and STD prevention programs may need to give additional attention to young MA users also affected by alcohol abuse. Other key findings regard drug trade activities (Table 1). A less studied aspect of drug using populations, information about the drug economy may inform the design of drug control policies. Data from our study suggests that young Thai MA users routinely participate in the drug trade. Of all MA users half had sold MA and nearly half had received money from dealing drugs. Frequent alcohol users in this population were even more likely to engage in these drug trade activities than those using alcohol infrequently. Furthermore, nearly 70% of all MA users obtained MA from someone else. These findings underscore the economic determinants of MA abuse and suggest a decentralized pattern of MA distribution in Thailand, where petty trade and micro-level sales are thought to be pervasive 7. Researchers have shown that taking part in the drug economy places drug users in a position to influence others 24. These findings further suggest that peer outreach programs employing social network-based, drug reduction interventions could be especially useful for addressing MA drug dependence in Thailand. Such interventions would be a humane alternative to past Thai MA drug control policies, such as the repressive war on drugs, which resulted in widespread human rights abuses including thousands of extrajudicial killings 25. Some study limitations must be considered. First, the study was limited by only having crosssectional data on correlates and prevalence of STD and HIV. Thus, temporality of exposure

16 and outcome could not be ensured. Second, since the study did not use probability sampling to recruit its participants, the findings presented here may not be applicable to all young MA users. However, the findings here do yield important information about STD risks and prevalence among young, treatment-seeking MA users and their drug and sexual networks in northern Thailand. Finally, measures of alcohol use other than consumption frequency may have been more appropriate for assessing variations in STD risks by alcohol use among this population. Others researchers have suggested that incorporating daily alcohol consumption quantity may lead to more accurate measurement of level of alcohol abuse 26. While information on quantity of consumption was not available in our study, the measure of frequency used did show a statistically significant association with the CAGE, a wellestablished screening tool for problem drinking 15 (Table 1), indicating its potential validity as a measure of level of alcohol abuse. In conclusion, we observed a high prevalence of STDs and associated drug and sexual risk factors among young, active MA users in Northern Thailand. Additionally, poly-drug use of alcohol among this population was associated with higher risk profiles for drug use, sexual behavior and drug trade activities. Integrated risk reduction programs targeting MA drug and alcohol dependence as well as HIV/STD transmission among young MA users should be developed. Network-based harm reduction interventions may be especially effective, particularly when addressing the drug economy-related activities of the MA using populations they serve.

17 References 1. World Drug Report United Nations Office for Drug Control and Crime Prevention. United Nations Publications. Geneva, Switzerland, Sherman SG, Aramrattana A, Celentano DD. Researching the effects of the Thai war on drugs: public health research in a human rights crisis. (In press). 3. US Department of State. International narcotics control strategy report, Department of State, Washington D.C. 4. Sattah MV, Supawitkul S, Dondero TJ, et al. Prevalence of and risk factors for methamphetamine use in northern Thai youth: results of an audio-computer-assisted selfinterviewing survey with urine testing. Addiction 2002; 97: Comer SD, Hart CL, Ward AS, et al. Effects of repeated oral methamphetamine administration in humans. Psychopharmacology (Berl) 2001; 155: Molitor F, Truax SR, Ruiz JD, Sun RK. Association of methamphetamine use during sex with risky sexual behaviors and HIV infection among non-injection drug users. West J Med 1998; 168(2): Beyrer C, Razak MH, Jittiwutikarn J, et al. Methamphetamine users in northern Thailand: changing demographics and risks for HIV and STD among treatment-seeking substance abusers. International Journal of STD & AIDS 2004; 15: Wu L, Schlenger WE, Galvin DM. Concurrent use of methamphetamine, MDMA, LSD, ketamine, GHB, and flunitrazepam among American youths. Drug and Alcohol Abuse (In press). 9. Goldsamt LA, O Brien J, Clatts MC, McGuire LS. The Relationship Between Club Drug Use and Other Drug Use: A Survey of New York City Middle School Students. Substance Use & Misuse, 40: Cook RL, Clark DB. Is there an association between alcohol consumption and sexually transmitted diseases? A Systematic Review. Sex Transm Dis 2005; 32(3): Ericksen KP, Trocki KF. Sex, alcohol and sexually transmitted diseases: A national survey. Fam Plann Perspect 1994; 26: Razak MH, Jittiwutikarn J, Suriyanon V, et al. HIV prevalence and risks among injection and non-injection drug users in northern Thailand: Need for comprehensive HIV prevention program. JAIDS 2003;33: World Health Organization. Guidelines for the management of sexually transmitted infections. Available at:

18 Accessed April 16, S.A. Maisto, G.J. Connors and J.P. Allen, Contrasting self-report screens for alcohol problems: a review. Alcohol Clin Exp Res 19 6 (1995), pp J.T. Hays and W.A. Spickard, Jr., Alcoholism: early diagnosis and intervention. J Gen Intern Med 2 6 (1987), pp Sivaram S, Johnson S, Bentley ME et al. Sexual health promotion in Chennai, India: key role of communication among social networks. Health Promot Int Dec;20(4): Sivaram S, Srikrishnan AK, Latkin CA et al. Development of an opinion leader-led HIV prevention intervention among alcohol users in Chennai, India. AIDS Educ Prev Apr;16(2): Amirkhanian YA, Kelly JA, Kabakchieva E, et al. A randomized social network HIV prevention trial with young men who have sex with men in Russia and Bulgaria. AIDS 2005 Nov 4; 19(16): Latkin CA, Forman V, Knowlton A, et al. Norms, social networks, and HIV-related risk behaviors among urban disadvantaged drug users. Soc Sci Med Feb; 56(3): Latkin CA. Outreach in natural settings: the user of peer leaders for HIV prevention among injecting drug users networks. Public Health Rep Jun; 113 Suppl 1: Nebelkopf E, Penagos M. Holistic Native network: integrated HIV/AIDS, substance abuse, and mental health services for Native Americans in San Francisco. J Psychoactive Drugs Sep; 37(3): Aguilera S, Plasencia AV. Culturally appropriate HIV/AIDS and substance abuse prevention programs for urban Native youth. J Psychoactive Drugs Sep; 37(3): Runn RA, Lee MA, Callahan DB, et al. Integrating hepatitis, STD, and HIV services into a drug rehabilitation program. Am J Prev Med Jul; 29(1): Sherman SG, Latkin CA. Drug users involvement in the drug economy: implications for harm reduction and HIV prevention programs. J Urban Health Jun; 79(2): Human Rights Watch Thailand Not Enough Graves: The War on Drugs, HIV/AIDS, and Violations of Human Rights. Retrieved April 27, 2006, from Dawson DA. Methodological Issues in Measuring Alcohol Consumption. Alcohol Research & Health 2003; 27(1):18-29.

19 Table 1: Demographic, Drug, Sexual Behavior and STD Characteristics of Study Population and by Frequency of Alcohol Use (n=530) Characteristic p-value Total (%) Infrequent Alcohol Consumption * Frequent Alcohol Consumption* Total 530 (100.0) 259 (48.9) 271 (51.1) Demographic Variables Age (35.5) 74 (28.6) 114 (42.1) p = Sex Male 401 (75.7) 181 (69.9) 220 (81.2) p = Education Less than High School 429 (80.9) 215 (83) 214 (79) High School or more 101 (19.1) 44 (17) 57 (21) p = Current Student 208 (39.3) 115 (44.4) 93 (34.3) p = Drug Use Factors Mean Age (SD), 1 st MA Use 15.0 (1.9) 15.2 (1.8) 14.7 (1.9) p = Average MA Use, past 30 days Less than 4 times/week 458 (86.4) 232 (89.6) 226 (83.4) Four times or more per week 72 (13.6) 27 (10.4) 45 (16.6) p = Method of MA Purchase Someone else bought 271 (51.1) 134 (51.7) 137 (50.6) Self-Purchase 154 (29.1) 71 (27.4) 83 (30.6) Someone gave for free 89 (16.8) 48 (18.5) 41 (15.1) p = From Dealing Drugs 16 (3.0) 6 (2.3) 10 (3.7) Confirmed Alcoholism by DSM-IV Criteria 252 (48.0) 96 (37.1) 156 (57.6) p = Sexual Risk Factors Ever had Sexual Intercourse 528 (99.6) 257 (99.2) 271 (100) p = Mean age at First Sexual Intercourse (SD) 15.5 (1.7) 15.7 (1.7) 15.3 (1.7) p = Had Casual Sex in past 12 months 488 (92.1) 100 (41.5) 119 (48.2) p = Used Condoms During Sex, past 30 days 457 (86.2) Always 90 (19.7) 50 (22.5) 40 (17) Less than Always 367 (80.3) 172 (77.5) 195 (83) p = Lifetime Partners i, Mean (SD) 12.5 (16.3) 9.7 (14.5) 15.1 (17.6) p = (8.2) 36 (14.1) 7 (2.6) (46.0) 128 (50.0) 114 (42.2) p = (45.8) 92 (35.9) 149 (55.2) Sex is a Usual Activity after MA Use 302 (57.0) 133 (51.4) 169 (62.4) p = 0.01 Drinking is a Usual Activity after MA Use 350 (66.0) 139 (53.7) 211 (77.9) p = MA Use Increased Sexual Desire, past 3 mo. 128 (24.2) 64 (24.7) 64 (23.6) p = Drug Economy Ever Sold MA 270 (50.9) 105 (40.5) 165 (60.9) p = Ever Paid from Delivering Drugs 243 (45.9) 104 (40.1) 139 (51.3) p = 0.01 History of Incarceration ii 139 (65.1) 53 (53.5) 83 (75.5) p = Sexually Transmitted Disease (STD) Any STD 157 (29.6) 57 (22) 100 (36.9) p = Any Ulcerative STD iii 39 (7.4) 13 (5) 26 (9.6) p = *Infrequent alcohol consumption 3 days/wk. Frequent alcohol consumption 4 days/wk i. Data missing (n=2); ii. Data missing (n=321); iii. Ulcerative STD includes HSV-2, syphilis.

20 Table 2. Unadjusted and Adjusted Risks for Prevalent STD among MA users who Consume Alcohol Infrequently Characteristic Number Tested STD Positive (%) Crude OR (95% CI) Adjusted OR (95% CI) Age < (17.8) (32.4) 2.21 (1.19, 4.09) 1.98 (1.02, 3.84) Sex Female (26.9) 1.0 Male (19.9) 0.67 ( 0.36, 1.25) Education Less than High School (20.5) 1.0 High School or more (29.6) 1.63 (0.79, 3.39) Current Student No (25) 1.0 Yes (18.3) 0.67 (0.37, 1.23) Average MA Use, past 30 days Less than 4 times per week (20.3) times or more per week (37) 2.32 (1.0, 5.39) Condom Use, past 30 days Less than Always (28.5) Always 50 7 (14) 0.41 (0.17, 0.97) 0.34 (0.14, 0.83) Sexual Partners (Lifetime) (5.6) (18.8) 3.92 (0.88, 17.5) (33.7) 8.64 (1.95, 38.3) 2.79 (1.47, 5.31) Had Casual Sex (Past 12 months) No (22) 1.0 Yes (21) 0.94 (0.51, 1.76) After MA Sex is not a usual activity (15.9) 1.0 Sex is a usual activity (27.8) 2.04 (1.11, 3.76)

21 Table 3. Unadjusted and Adjusted Risks for Prevalent STD among MA Users who Consume Alcohol Frequently Characteristic Number Tested STD Positive (%) Crude OR (95% CI) Adjusted OR (95% CI) Age < (33.8) (41.2) 1.38 (0.84, 2.27) Sex Female (54.9) Male (32.7) 0.4 (0.22, 0.74) 0.37 (0.19, 0.72) Education Less than High School (38.8) 1.0 High School or more (29.8) 0.67 (0.36, 1.26) Current Student No (41) 1.0 Yes (29) 0.59 (0.34, 1.01) Average MA Use, past 30 days Less than 4 times per week (35.4) times or more per week (44.4) 1.46 (0.76, 2.79) Condom Use (Past 30 days) Less than Always (39) 1.0 Always (27.5) 0.59 (0.28, 1.26) Sexual Partners (Lifetime) (28.6) (32.5) 1.2 (0.22, 6.49) (40.3) 1.7 (0.32, 8.97) 1.76 (1.01, 3.09) Had Casual Sex (Past 12 months) No (35.2) 1.0 Yes (38.7) 1.16 (0.69, 1.95) After MA Sex is not a usual activity (28.4) 1.0 Sex is a usual activity (42) 1.82 (1.08, 3.1) Table 4. Independent Risk Factors for Prevalent STD among all MA users Risk Factors Adjusted Odds Ratio P Values (95% CI) Age (1.02, 2.40) Male 0.48 (0.30, 0.77) Sexual Partners (Lifetime) (1.13, 13.8) (2.17, 26.6) Always Condom Use (past (0.29, 0.77) days) MA Use 4 times/wk 1.90 (1.06, 3.39) 0.03