Ricky N. Bluthenthal

Sexual transmission of HIV-1 among injection drug users in San Francisco, USA: risk-factor analysis

BACKGROUND Many new HIV-1 infections in the USA occur in injection drug users (IDUs). HIV-1seroconversion of IDUs is mainly associated with injection-related risk factors. Harm- reduction programmes concentrate on injection-risk behaviour. We aimed to establish whether injection or sexual risk factors, or both, were associated with HIV-1antibody seroconversion of street-recruited IDUs in San Francisco, from 1986 to 1998. METHODS IDUs were enrolled every 6 months from four community sites. We did a nested case-control study comparing 58 respondents who seroconverted between visits with 1134 controls who remained seronegative. Controls were matched with cases by sex and date. Adjusted odds ratios and 95% CI were calculated for men and women by use of conditional logistic regression. FINDINGS Men who had sex with men were 8.8 times as likely to seroconvert (95% CI 3.7-20.5) as heterosexual men. Women who reported having traded sex for money in the past year were 5.1 times as likely as others to seroconvert (95% CI 1.9-13.7). Women younger than 40 years were more likely to seroconvert than those 40 years or older (2.8 [1.05-7.6]), and women who reported having a steady sex-partner who injected drugs were less likely to seroconvert than other women (0.32 [0.11-0.92]). INTERPRETATION HIV-1 seroconversion of street-recruited IDUs in San Francisco is strongly associated with sexual behaviour. HIV-1risk might be reduced by incorporation of innovative sexual-risk-reduction strategies into harm-reduction programmes.

High Prevalence of Abscesses and Cellulitis Among Community-Recruited Injection Drug Users in San Francisco

The prevalence of and risk factors for abscesses and cellulitis were investigated among a community sample of injection drug users (IDUs). Participants were interviewed, and those with symptoms were examined. Of 169 IDUs, 54 (32%) had abscesses (n=35), cellulitis (n=5), or both (n=14); 27% had lanced their own abscesses; and 16% had self-treated with antibiotics they purchased on the street. IDUs who skin-popped (injected subcutaneously or intramuscularly) were more likely to have an abscess or cellulitis than those who had injected only intravenously (odds ratio, 4.9; 95% confidence interval, 2.2-11). The likelihood of abscesses and cellulitis increased with frequency of skin-popping and decreased with increasing duration of injection drug use. Abscesses are extremely prevalent among IDUs in San Francisco. Skin-popping is a major risk factor, and self-treatment is common.

The Effect of Syringe Exchange Use on High-Risk Injection Drug Users: A Cohort Study

Objective:To determine whether syringe exchange program use is associated with cessation of syringe sharing among high-risk injection drug users. Design and methods:Between 1992 and 1996, street-recruited injection drug users were interviewed and received HIV testing and counseling semi-annually, as part of a dynamic cohort study. We examined a cohort of 340 high-risk injection drug users for whom two observations, 6-months apart, were available and who reported syringe sharing at the first interview. Multivariate logistic regression analysis was performed to determine the relationship between syringe exchange program use and cessation of syringe sharing, while controlling for confounding factors. Results:At follow-up interview, 60% (204 of 340) reported quitting syringe sharing. High-risk injection drug users who began using the syringe exchange program were more likely to quit sharing syringes [adjusted odds ratio (AOR), 2.68; 95% confidence interval (CI), 1.35–5.33], as were those who continued using the syringe exchange program (AOR,1.98; 95% CI, 1.05–3.75) in comparison with non-syringe exchange program users, while controlling for confounding factors. Conclusions:The initiation and continuation of syringe exchange program use among high-risk injection drug users is independently associated with cessation of syringe sharing. Syringe exchange program use can be an important component in reducing the spread of blood-borne infectious diseases among high-risk injection drug users.

Predictors and Prevention of Nonfatal Overdose Among Street-Recruited Injection Heroin Users in the San Francisco Bay Area, 1998–1999

OBJECTIVES This study sought to determine prevalence of and risk factors for nonfatal recent overdose among street-recruited injection heroin users. METHODS From August 1998 through July 1999, 1427 heroin injectors were recruited from 6 inner-city neighborhoods in the San Francisco Bay Area, Calif, and interviewed. Factors hypothesized to be associated with recent overdose were analyzed with logistic regression. RESULTS Of the 1427 participants, 684 (48%) had had an overdose, 466 (33%) had experienced 2 or more overdose events, and 182 (13%) had had a recent overdose. In multiple logistic regression, being younger (adjusted odds ratio [OR] for each year of increasing age = 0.95; 95% confidence interval [CI] = 0.94, 0.97), having been arrested 3 or more times in the past year (adjusted OR = 2.50; 95% CI = 1.61, 3.87), drinking 4 or more alcoholic drinks per day (adjusted OR = 2.05; 95% CI = 1.37, 3.05), and having participated in methadone detoxification during the past year (adjusted OR = 1.47; 95% CI = 1.03, 2.09) were independently associated with recent overdose. Being homeless; identifying as gay, lesbian, bisexual, or transgender; having spent 5 or more years in prison or jail; and having engaged in sex work also were associated with recent overdose. CONCLUSIONS Targeted interventions that decrease risk for overdose are urgently needed.

HIV seroprevalence among street-recruited injection drug and crack cocaine users in 16 US municipalities.

OBJECTIVES This study deter- mined human immunodeficiency virus (HIV) seroprevalence and factors associated with HIV infection among street-recruited injection drug users and crack cocaine smokers. METHODS An analysis was performed on HIV serologies and risk behaviors of 6402 injection drug users and 3383 crack smokers in 16 US municipalities in 1992 and 1993. RESULTS HIV seroprevalence was 12.7% among injection drug users and 7.5% among crack smokers. Most high-seroprevalence municipalities (>25%) were located along the eastern seaboard of the United States. In high-seroprevalence municipalities, but not in others, HIV seroprevalence was higher for injection drug users than for crack smokers. Among injection drug users, cocaine injection, use of speedballs (cocaine or amphetamines with heroin), and sexual risk behaviors were independently associated with HIV infection. Among crack smokers, sexual risk behaviors were associated with HIV infection. CONCLUSIONS Injection drug users and crack smokers are at high risk for HIV infection.

Impact of law enforcement on syringe exchange programs: A look at Oakland and San Francisco

Drug paraphernalia and prescription laws make syringe exchange programs (SEPs) illegal in most states in the U.S. Nonetheless, SEPs have been started in 25 states and the District of Columbia as of September 1995. In some states like California and New Jersey, SEPs have operated despite police arrest of volunteers and clients. We examine the impact of police action and threat on SEPs by comparing an underground syringe exchange site (SES) in West Oakland to a tolerated SES in the Fillmore neighborhood of San Francisco. The following data sources are utilized: demographic and service utilization data from Alameda County Exchange (ACE) in West Oakland and Prevention Point Needle and Syringe Exchange (PPNSE) in the Fillmore, San Francisco; demographic and syringe exchange utilization information collected from street-recruited samples of injection drug users (IDUs) in West Oakland and the Fillmore; and participant observation of SES in these two communities. We found that police action and the threat of police action in West Oakland decreased utilization of SEP by IDUs, limited the number and diversity of volunteers at SES, and inhibited the operation and expansion of SEP.

Collateral damage in the war on drugs: HIV risk behaviors among injection drug users

Abstract Objective: To determine whether two key War on Drugs policies, the criminalization of syringes and the disqualification of drug users from the Supplemental Security Income (SSI) program, are associated with injection-related human immunodeficiency virus (HIV) risk behaviors among injection drug users (IDUs). Methods: IDUs were interviewed regarding HIV risk behaviors, drug use, and criminal activities in six San Francisco Bay Area communities in 1996 and followed through 1997 ( n =1257). Multivariate analysis was conducted to examine the association between concern about arrest while carrying drug paraphernalia and injection-related risk behaviors. Regarding SSI, respondents were interviewed before (1996) and after (1997) drug and alcohol addicts were disqualified from SSI ( n =88). Bivariate analysis was conducted comparing IDUs who lost SSI benefits with those who retained benefits. Results: Among our study sample, 32% of IDUs reported being concerned about possible arrest while carrying drug paraphernalia. In multivariate analysis, concerned IDUs were over one-and-a-half times more likely to share syringes than IDUs not concerned (adjusted odds ratio=1.74; 95% confidence interval=1.24, 2.44). Regarding SSI, 60% (53/88) of baseline SSI recipients had lost benefits by their follow-up interview. IDUs who lost benefits were more likely to participate in illegal activities (48 vs. 27%; P P P

Drug Paraphernalia Laws and Injection-Related Infectious Disease Risk among Drug Injectors:

Drug paraphernalia laws in 47 U.S. states make it illegal for injection drug users (IDUs) to possess syringes. It has been suggested that these laws lead to syringe sharing by deterring IDUs from carrying their own syringes. We examined the relationship between concern about arrest while carrying drug paraphernalia and injection-related risk behaviors among street-recruited IDUs in Northern California. In 1996, 424 IDUs were interviewed, of whom 76 percent were African American, 36 percent were female, and 15 percent were HIV positive. Thirty-five percent (150) reported concern about being arrested while carrying drug paraphernalia. In multivariate analyses that controlled for potential confounders, IDUs concerned about being arrested were significantly more likely than other IDUs to share syringes (adjusted odds ratio [AOR] =2.28; 95 percent confidence interval [Cl]=1.19, 4.34) and injection supplies (AOR= 3.23; 95 percent Cl=2.03, 5.13). These data suggest that decriminalizing syringes and needles would likely result in reductions in the behaviors that expose IDUs to blood borne viruses.

Use of an illegal syringe exchange and injection-related risk behaviors among street-recruited injection drug users in Oakland, California, 1992 to 1995:

OBJECTIVE To determine factors associated with syringe and injection supply sharing among injection drug users (IDUs) in a community with an illegal underground syringe exchange program (SEP). METHODS From 1992 to 1995, semiannual cross-sectional samples of IDUs were recruited in Oakland, California. To account for multiple observations from the same individual, we used general estimating equations with logit transformations to determine factors associated with sharing syringes and other injection supplies. RESULTS 1304 IDUs were interviewed; 684 (53%) returned for more than one interview. 2830 interviews were available for analysis. SEP use increased and syringe and supply sharing declined from 1992 to 1995 among study participants. In multivariate analysis, SEP users were less likely to share syringes than non-SEP users (adjusted odds ratio [AOR] = 0.57; 95% confidence interval [CI] = 0.46-0.72). SEP use was not significantly associated with the sharing of injection supplies (AOR = 0.85; 95% CI = 0.68-1.07). Syringe sharing and injection supply sharing were significantly less likely to occur among African American and HIV-positive IDUs. CONCLUSIONS These data suggest that illegal SEPs can be effective HIV prevention programs. Lower rates of syringe-based risk behaviors among African American and HIV-positive IDUs are encouraging.

Sexual Risk Among Injection Drug Users Recruited from Syringe Exchange Programs in California

Objective: The objective of this study was to examine correlates of sexual risk among injection drug users (IDUs). Study: A total of 1445 IDUs were recruited from California syringe exchange programs. Results: Consistent condom use was independently related to being HIV-positive, having multiple sex partners, not having a steady partner, not sharing syringes, and not injecting amphetamines for men; and engaging in sex work, not sharing syringes, and not having a steady partner for women. Having multiple recent sexual partnerships that included a steady partner was related to engaging in sex work, speedball injection, and amphetamine use among men; and younger age, having had a sexually transmitted disease (STD), engaging in sex work, and using alcohol among women. Having heterosexual anal sex was related to having had an STD, having multiple sexual partners, using amphetamines, and syringe-sharing for men; and younger age and amphetamine use for women. Conclusions: Comprehensive prevention interventions addressing multiple sexual and injection risk behaviors are needed for IDUs.