Faculty Bibliography

Risk networks can transmit HIV or other infections; social networks can transmit social influence and thus help shape norms and behaviors. This primarily-theoretical paper starts with a review of network concepts, and then presents data from a New York network study to study patterns of sexual and injection linkages among IDUs and other drug users and nonusers, men who have sex with men, women who have sex with women, other men and other women in a high-risk community and the distribution of HIV, sex at group sex events, and health intravention behaviors in this network. It then discusses how risk network microstructures might influence HIV epidemics and urban vulnerability to epidemics; what social and other forces (such as "Big Events" like wars or ecological disasters) might shape networks and their associated norms, intraventions, practices and behaviors; and how network theory and research have and may continue to contribute to developing interventions against HIV epidemics.

OBJECTIVES/OBJECTIVE:To examine gender differences in drug injection equipment sharing at injecting initiation. METHODS:Young injecting drug users (IDUs) in New York City February 1999-2003 were surveyed about injection risk behaviors and circumstances at initiation. Analyses were gender-stratified and excluded participants who initiated alone. Multiple logistic regression estimated adjusted odds ratios. RESULTS:Participants (n=249) were 66% male and 82% White. Mean initiation age was 19.2; mean years since initiating was 3.0. Women were significantly more likely to cite social network influence as a reason for initiating, to have male and sex partner initiators, and to share injecting equipment than men. Among women, sharing any injection equipment was associated with initiation by a sex partner and having > or =2 people present. Among men, being injected by someone else predicted sharing any injection equipment, while using a legally obtained syringe was protective. CONCLUSIONS:Social persuasion stemming from sexual and/or social relationships with IDUs may increase women's risk of sharing injection equipment at initiation, and consequently, their early parenteral risk of acquiring blood-borne infections. Interventions should focus on likely initiates, especially women in injecting-discordant sex partnerships, and IDUs (potential initiators).

We examine injecting and sexual risk correlates of hepatitis B (HBV) and hepatitis C (HCV) seroprevalence among new injecting drug users (IDUs) (age 18-30 years, injecting < or =6 years). Participants were interviewed/serotested (HIVab, HBVcAb, HCVab) in New York City, February 1999-February 2003. Gender-stratified, multivariate logistic regression was conducted. Participants (N=259) were: 68% male; 81% white. Women were more likely to test HCV seropositive (42% versus 27%) and men HBV seropositive (24% versus 12%); HIV seroprevalence was low (3%). Among both men and women, HBV seropositivity was associated with ever selling sex, and HCV seropositivity with ever having had infected (HIV, HBV or HCV) sex partners (among those ever sharing injecting equipment). Among women only, HBV seropositivity was associated with ever having had infected sex partners (regardless of ever sharing injecting equipment), and HCV seropositivity with > or =300 lifetime drug injections. Among men only, HCV seropositivity was associated with > or =40 lifetime number of sex partners (among those never sharing injecting equipment). In this new IDU sample, HBV and HCV seroprevalence differed by gender and were considerably higher than HIV seroprevalence. Early interventions, targeting injecting and sexual risks and including HBV vaccination, are needed among new IDUs to prevent HBV, HCV and, potentially, HIV epidemics.

"Social capital" has been critiqued as distracting attention from inequalities and policies that produce ill health. We support this critique insofar as social capital refers to the degree of trust and consensus in a locality, but find value in another dimension often included in the concept of social capital--social network ties and their associated communication patterns. We present a case study of Bushwick, a community of 100,000 people in Brooklyn NY, to suggest that the network aspect of "social capital" is useful to understand the active, on-the-ground processes by which residents of some neighborhoods beset by poverty, racial/ethnic subordination, and internal divisions (that themselves arise from inequalities and state policies) work out ways to defend their own and others' safety and health. We use a combination of population-representative survey data for young adults; sexual network survey data; and ethnography to show that Bushwick residents (including drug users and dealers) have used social network ties, communication, and normative pressures to reduce the extent to which they are put at risk by the drug trade and by drug-use-related HIV/AIDS in spite of conflicting interests, disparate values, and widespread distrust both of other community members and of dominant social institutions. This was done by "intravention" health communications, development of protective norms, informal negotiations, and other forms of adjustments within and among various groups--but it occurred in the absence of trust or consensus in this community. We conclude both (1) that social network interpretations of "social capital" might be better conceptualized in dialectic terms as collective action to survive in a harsh social order, and (2) that the social capital theory emphasis on trust and consensus as important causal factors for lowering drug-related risks at the community level may be a romanticized and erroneous perspective.

AIMS: To characterize heroin and cocaine users in New York City who have changed from injection to non-injection drug administration and to identify factors associated with long-term non-injection use. DESIGN: Two cross-sectional studies of heroin and cocaine users in New York City. SETTINGS AND PARTICIPANTS: New admissions were recruited at drug abuse treatment programs (2000-04) and respondent-driven sampling was used to recruit drug users from the community (2004). Both injecting and non-injecting drug users participated in each study. 'Former injectors' were defined operationally as people who had used heroin and/or cocaine in the 6 months prior to the interview and who had injected illicit drugs in the past, but whose most recent injection was more than 6 months before the study interview. 'Current' injectors were defined as people who had injected heroin and/or cocaine in the 6 months prior to the interview. MEASUREMENTS: A structured interview on drug use history was administered, and a serum sample was collected and tested for the human immunodeficiency virus (HIV). FINDINGS: A total of 104 former injectors was recruited for the drug abuse treatment program study, and 229 current injectors were recruited for the community recruitment study; 160 former injectors and 1731 current injectors were recruited from the drug abuse treatment study. Compared with the current injectors, former injectors were older and more likely to be African American. The former injectors reported long intervals since their most recent injection, a mean of 8 years in the drug abuse treatment program study and a mean of 12 years in the community recruitment study. The most common reasons for stopping injection drug use included concerns about health, social stigmatization and self-image, and preference for intranasal use as a route of drug administration. The results were highly consistent across the two studies. CONCLUSIONS: The transition from injection to non-injection use appears to be relatively stable behavior change for many former injectors, who report a decade or more without injecting. Developing a greater understanding of the transition from injection to stable non-injection drug use may provide insights into the natural histories of drug use and addiction.

BACKGROUND:Many heroin users do not inject drugs but may still be at risk of infection with human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV), via sexual or other noninjection-related activity. METHODS:Noninjecting heroin users (NIUs) in New York City who were recruited and prospectively followed during March 1996-February 2003 were tested for anti-HIV, anti-hepatitis B core antigen, and anti-HCV and were interviewed about their sexual and other noninjecting risk. A seroconversion is represented by the first positive test result after the last negative test result. Hazard ratios (HRs) (P<.05) were estimated by use of Cox proportional hazards regression. RESULTS:Of 253 HIV-negative participants, 2 seroconverted (0.29/100 person-years at risk [pyar]); of 184 HBV-negative participants, 16 (3.3/100 pyar); and, of 219 HCV-negative participants, 16 (2.7/100 pyar). Independent predictors of seroconversion were, for HBV, being a female who engages in unprotected receptive anal sex (HR, 6.8), having short-term sex partners (HR, 6.2), and being a male with male sex partners (HR, 5.7); for HCV, being a male who receives money/drugs for sex (HR, 5.6) and sharing noninjecting crack-use equipment (HR, 4.5). CONCLUSIONS:NIUs are at considerable risk of HBV infection via high-risk sex; and, for HCV, via high-risk sexual activity and the sharing of noninjecting crack-use equipment. Interventions in NIUs must seek to reduce high-risk sexual activity and the sharing of noninjecting drug-use equipment.

Community activism can be important in shaping public health policies. For example, political pressure and direct action from grassroots activists have been central to the formation of syringe exchange programs (SEPs) in the United States. We explored why SEPs are present in some localities but not others, hypothesizing that programs are unevenly distributed across geographic areas as a result of political, socioeconomic, and organizational characteristics of localities, including needs, resources, and local opposition. We examined the effects of these factors on whether SEPs were present in different US metropolitan statistical areas in 2000. Predictors of the presence of an SEP included percentage of the population with a college education, the existence of local AIDS Coalition to Unleash Power (ACT UP) chapters, and the percentage of men who have sex with men in the population. Need was not a predictor.

This paper discusses the user side of harm reduction, focusing to some extent on the early responses to the HIV/AIDS epidemic in each of four sets of localities-New York City, Rotterdam, Buenos Aires, and sites in Central Asia. Using available qualitative and quantitative information, we present a series of vignettes about user activities in four different localities in behalf of reducing drug-related harm. Some of these activities have been micro-social (small group) activities; others have been conducted by formal organizations of users that the users organized at their own initiative. In spite of the limitations of the methodology, the data suggest that users' activities have helped limit HIV spread. These activities are shaped by broader social contexts, such as the extent to which drug scenes are integrated with broader social networks and the way the political and economic systems impinge on drug users' lives. Drug users are active agents in their own individual and collective behalf, and in helping to protect wider communities. Harm reduction activities and research should take note of and draw upon both the micro-social and formal organizations of users. Finally, both researchers and policy makers should help develop ways to enable and support both micro-social and formally organized action by users.

OBJECTIVES/OBJECTIVE:We analyzed the relations of two 1990 dimensions of racial residential segregation (isolation and concentration) with 1998 injection drug use prevalence among Black adult residents of 93 large US metropolitan statistical areas (MSAs). METHODS:We estimated injection drug use prevalence among Black adults in each MSA by analyzing 3 databases documenting injection drug users' encounters with the health care system. Multiple linear regression methods were used to investigate the relationship of isolation and concentration to the natural logarithm of Black adult injection drug use prevalence, controlling for possible confounders. RESULTS:The median injection drug use prevalence was 1983 per 100000 Black adults (interquartile range: 1422 to 2759 per 100000). The median isolation index was 0.48 (range: 0.05 to 0.84): in half the MSAs studied, the average Black resident inhabited a census tract where 48% or more of the residents were Black. The multiple regression model indicates that an increase of 0.50 in the isolation index was associated with a 23% increase in injection drug use prevalence among Black adults. Concentration was unrelated to the outcome. CONCLUSIONS:Residential isolation is positively related to Black injection drug use prevalence in MSAs. Research into the pathways linking isolation to injection drug use is needed.

OBJECTIVE: To compare HIV prevalence among injecting and non-injecting heroin and cocaine users in New York City. As HIV is efficiently transmitted through the sharing of drug-injecting equipment, HIV infection has historically been higher among injecting drug users. DESIGN: Two separate cross-sectional surveys, both with HIV counseling and testing and drug use and HIV risk behavior questionnaires. METHODS: Injecting and non-injecting heroin and cocaine users recruited at detoxification and methadone maintenance treatment from 2001-2004 (n = 2121) and recruited through respondent-driven sampling from a research storefront in 2004 (n = 448). RESULTS: In both studies, HIV prevalence was nearly identical among current injectors (injected in the last 6 months) and heroin and cocaine users who had never injected: 13% [95% confidence interval (CI), 12-15%] among current injectors and 12% (95% CI, 9-16%) among never-injectors in the drug treatment program study, and 15% (95% CI, 11-19%) among current injectors and 17% (95% CI, 12-21%) among never injectors in the respondent driven sampling storefront study. The 95% CIs overlapped in all gender and race/ethnicity subgroup comparisons of HIV prevalence in both studies. CONCLUSIONS: The very large HIV epidemic among drug users in New York City appears to be entering a new phase, in which sexual transmission is of increasing importance. Additional prevention programs are needed to address this transition.