National Institute on Drug Abuse
Director's Report to the National Advisory Council on Drug Abuse
September, 1998
Research Findings
AIDS Research
Hepatitis A (HAV) Among Homosexual Men and Injection Drug Users: More Evidence for Vaccination
Serum samples from 300 IDUs, 300 homosexual men and 300 blood donors were tested for the presence of total antibody to Hepatitis A virus (anti-HAV). Anti-HAV was detected in 66% of IDUs, 32% of homosexual men, and 14% of blood donors. Anti-HAV was not significantly associated with high-risk drug-using behaviors (p>.10), but was more prevalent among IDUs with annual incomes <$5000 (p<.02). The data indicate that IDUs are at increased risk for HAV infection but that factors related to low socioeconomic status contribute more to the occurrence of HAV infection among IDUs than does injection drug use. Data also indicate that IDUs and persons at risk for injection drug use should receive HAV vaccine. Villano, S.A., Nelson, K.E., Vlahov, D. et al., Clin. Infect. Dis., 25, pp.726-728, 1997.
Persistence and Clinical Significance of Hepatitis G Virus (HGV) Infections in Injecting Drug Users
To determine the prevalence of HGV infection and its association with liver disease, HGV RNA was assessed in the most recent serum sample for 246 long-term IDUs and in prior specimens for those found HGV-RNA positive. HGV RNA was detected at the most recent visit in 15%. Of those found positive, 82% also had HGV-RNA positive serum samples at all prior visits occurring a median of 6.1 years earlier. HGV-positive IDUs were younger and had fewer years duration of drug use, suggesting that HGV RNA had previously been cleared. Serial samples from 29 short-term IDUs detected HGV RNA in 9 (31%) and in 56%of those HGV infection cleared. No differences were detected in serum levels of liver-related enzymes among HGV RNA-positive vs. HGV RNA-negative IDUs (p>.20). These data indicate that HGV infection is not associated with hepatic inflammation, and that HGV clearance occurs after many acute infections but uncommonly in persons who remain RNA-positive years after exposure. Thomas, D.L., Nakatsuji, Y., Shih, J.W. et al., J. Infect. Dis., 176, pp. 586-592, 1997.
The Influence of Drug Use Patterns on the Rate of CD4+ Lymphocyte Decline Among HIV Infected IDUs
An analysis to assess the relationship between injecting drug use patterns (e.g., frequency, duration, continuous vs. intermittent) and the rate of CD4+ lymphocyte decline (change in CD4 count per month as compared with previous CD4 count) was performed in a cohort of active IDUs. Among 605 IDUs, the median initial CD4 count was 513 and the mean change in CD4 count was -3.2 cells x 10(6)/l per month. The rate of CD4 decline was higher in those with a higher level of CD4 (p<.01) and greater with length of drug use (p<.01), but did not vary by injection frequency or injection intensity by drug type, or by pattern of administration (intermittent vs. continuous). Although animal studies have suggested that the pattern of drug administration and episodes of withdrawal or overdose might have an impact on the rate of CD4 decline, injection patterns by self-report were not associated with the rate of CD4 decline in this study of active injectors. Lyles, C.M., Margolick, J.B., Astemborski, J. et al., AIDS, 11, pp.1255-1262, 1997.
Unique Volume Presents Findings from the NIDA CA on Women's Drug Use and HIV Risk
A recent volume brings together empirical findings from NIDA's multisite CA research program which highlight a number of factors related to HIV infection among women who inject drugs and/or smoke crack cocaine, or who are the sex partners of individuals who use these drugs. Bringing their risk factors to light is timely and critical at this point in the epidemic, when women's vulnerability to HIV disease is becoming increasingly apparent. Worldwide, women account for 42% of adults living with HIV/AIDS, but women's acquisition of the virus has begun to grow more rapidly than it has for men. Drug use is well recognized as playing a major role in the spread of this disease: up to 46% of women's AIDS cases have been directly attributed to injection drug use and as much as 18% to women's heterosexual contacts with injection drug users. The papers in this volume are presented in five major sections: an overview of findings and research needs on women drug users and HIV prevention; HIV risk behavior change of female drug users; single CA site descriptions; contextual variables in women's HIV risk behaviors; gender differences in HIV risk behavior and health status of drug users; and a unique population of women at risk -- women who trade sex for money and drugs. Stevens, S.J., Tortu, S., and Coyle, S.L. (Eds.). Women, Drug Use, and HIV Infection. Binghamton, N.Y.: Haworth Medical Press, 1998 (co-published simultaneously as Women and Health, 27 (_), 1998).
Special Issue Devoted to HIV Prevention for Injection Drug Users
Recently, a special supplement on HIV prevention for injection drug users was published by the Journal of Acquired Immune Deficiency Syndrome and Human Retrovirology. Edited by David Vlahov, Ph.D. of Johns Hopkins School of Hygiene and Public Health and T. Stephen Jones, M.D. of the Centers for Disease Control and Prevention, the supplement focuses on issues related to use of sterile syringes as an HIV prevention measure by drug users who continue to inject. A number of NIDA-sponsored researchers contributed articles to the supplement, including Drs. C. McCoy, L. Metsch, D. Chitwood et al., who assessed the frequency of multiperson use of needles, syringes, cookers, cotton, and water relative to the transfer of blood and blood-borne infections in approximately 4,000 IDUs. They report that nearly two-thirds of potential exposures to blood-borne infections among the IDUs were from multiperson use of cookers, cotton, and water, indicating the importance of considering all drug preparation and injection practices that could allow transfer of blood-borne infections among IDUs at parenteral transmission in any intervention programs. Drs. R. Heimer, K. Khoshnood, J. Guydish, and B. Junge contributed an article on the effects of syringe exchange programs on syringe use and reuse. They used multiple methods to estimate injections per syringe by SEP clients in San Francisco, Chicago, Baltimore, and New Haven, and found that SEP participation was significantly associated with increases in once-only use of syringes. The findings add to the weight of evidence which shows that SEPs reduce the transmission of syringe-borne infections such as HIV and hepatitis. Drs. P. Keyl, L. Gruskin, K. Casano et al., describe findings from their study on community attitudes toward Needle Exchange Programs (NEPs) in Baltimore. They conducted household interviews with a random sample of residents in six census tracts in the city, and found that, even though 72% of the respondents thought NEPs would attract IDUs to the neighborhood, 65% favored NEPs and 47% favored pharmacy sales without prescriptions. Factors independently associated with acceptance of NEPs were the perceptions that they decrease the numbers of discarded needles on the street, do not encourage a person to inject drugs, and decrease the incidence of HIV. Jones, T.S. and Vlahov, D. (Eds.). Journal of Acquired Immune Deficiency Syndromes and Human Retrovirology: HIV Prevention for Injection Drug Users, 18(supplement 1), July 1998.
Psychosocial Interventions and the Prevention of HIV Risk Behaviors in IDUs
Researchers examined the scientific evidence on the effectiveness of psychosocial interventions in reducing the risk of infection with HIV in IDUs. They reviewed 19 published studies on the effectiveness of individual counseling, HIV testing, group interventions, street outreach, and a "social" intervention designed to change norms for safer behaviors. Eight of 15 studies that examined behavioral outcomes provided evidence of the effectiveness of an experimental intervention, compared with a control or comparison group. Yet, there were a number of competing hypotheses which may have explained the findings (e.g., participation in an intervention evaluation itself may be a valuable intervention). The researchers discuss the importance of examining the efficacy of health risk assessment when developing interventions, and the need to develop unobtrusive measures and to assess the impact of behavioral assessments when evaluating them. Because a substantial proportion of subjects receiving interventions report unacceptably high levels of risk behaviors, more potent interventions are needed, such as those designed to change the norms of entire communities of drug users concerning safer injection and safer sex. Gibson, D.R., McCusker, J., and Chesney, M. Effectiveness of Psychosocial Interventions in Preventing HIV Risk Behavior in Injecting Drug Users. AIDS, 12, pp. 919-929, 1998.
Condom Use Among Filipina Sex Workers
Until fairly recently, the Philippines did not witness the epidemic proportions of the AIDS virus that have been seen in certain parts of Asia such as Thailand and India; however, recent statistics indicate that there may be 18,000 adult carriers of the AIDS virus in the Philippines. Furthermore, commercial sex work promotes the spread of HIV, and there are about 265,000 sex workers in the Philippines. Findings are presented from the baseline assessment of a community-based HIV/STD prevention intervention among registered commercial sex workers (N = 1394) and managers of the establishments that employ them in the Philippines in this study. The primary goal of the intervention is to promote safer sexual practices among Filipina sex workers. The sex workers' knowledge, attitudes, behaviors, and perceptions of establishment policies concerning HIV prevention were assessed. Results indicated that most establishments do not have clear policies and practices for condom use between the sex workers and their clients. The best predictor for use of condoms with clients was whether condoms were available at the establishment. The findings point to the importance of an intervention that stresses changes in establishment policies and expectations as a means of reducing risk behaviors associated with HIV/STD transmission. Morisky, D.E., Tiglao, T.V., Sneed, C.D., Tempongko, S.B., Baltazar, J.C., Detels, R., & Stein, J.A. The Effects of Establishment Practices, Knowledge and Attitudes on Condom Use Among Filipina Sex Workers. AIDS Care, 10, pp. 213-220, 1998.
Drug-Involved Women Prefer Female-Controlled Protection from HIV and Other STDs
A multisite research project was initiated in 1996 to examine the acceptability of the female condom among women at high risk for HIV and other STDs and determine its potential utility as an additional risk-reduction tool for drug-involved women. Six research sites that were part of the collaborative, cross-site NIDA CA participated in the study: San Antonio, St. Louis, Washington, DC, Rio de Janeiro, Lexington/Louisville, and Raleigh/Durham. The study sought to introduce the female condom to a large sample of women drug users, to explore its acceptability as a risk-reduction device among these women, and to examine correlates of its use. This article reports findings from three of the six sites: San Antonio, St. Louis, and Rio de Janeiro. All of the female respondents participated in a female condom education program, and were asked to report their experiences at two points of contact. Outcome data indicated that a sizable proportion of the women who were followed up reported use of the female condom on one or more occasions of heterosexual contact, and that many women preferred the female condom to the male condom in terms of overall satisfaction, suggesting that there is a viable role for this device in the HIV prevention field. Surratt, H.L., Wechsberg, W.M., Cottler, L.B., Leukefeld, C.G., Klein, H., and Desmond, D.P. Acceptability of the Female Condom Among Women at Risk for HIV Infection. American Behavioral Scientist, 41(8), pp. 1157-1170, May 1998.
Street Research with Cocaine Users in Brazil Reported as Feasible and Effective
Researchers assessed the impact of an HIV risk reduction program on risky behaviors in a population of street cocaine users in Rio de Janeiro, Brazil. Pre- and post-intervention data were collected, and changes in the frequency of drug use, sexual risk behaviors, and other life-situation variables were examined. Participation in the program was associated with a significant decrease in the average number of days of cocaine use and a significant increase in employment and income. Significant increases in condom use were also documented. The data suggest that this population of street cocaine users was capable of understanding the severity of AIDS as well as learning and applying specific risk-reduction techniques to their behavior. The results further demonstrate the feasibility of conducting street research among an at-risk population of cocaine users in Brazil and in other countries in which there is little tradition of research with out-of-treatment drug users. McBride, D.C., Inciardi, J.A., Surratt, H.L., et al. The Impact of an HIV Risk-Reduction Program Among Street Drug Users in Rio de Janeiro, Brazil. American Behavioral Scientist, 41(8), pp. 1171-1184, May 1998.
Rational Model Links Needs, Impoverishment, and an Increase in HIV Risk Behaviors
Researchers considered a rational model where the needs of the HIV+ population are met by individual resources, plus public resources, and network resources (contributions by family and friends). They examine the argument made by some economists that since HIV transmission is embedded in a pattern of risk, the fact that AIDS shortens the life expectancy of the chronically indigent amounts to an economic (if not an ethical) boon as a cost-containment mechanism for social welfare expenditures. The rational model suggests otherwise because, as levels of social welfare expenditures or public transfers decrease and fail to meet the needs of HIV+ persons, the risky behavior and HIV infection rate among network altruists spiral upward as they become impoverished in meeting the shortfall in public transfers. The emotional dynamics of networks (family, friends) are potentially an important resource in the construction of an adequate public response to social problems. Bell, D.C., Richard, A.J., Montoya, I.D., et al. Social Network Utility and the Economics of Risk: The Case of HIV. Journal of Economic Behavior and Organization, 33, pp. 195-205, 1998.
Amphetamine, Substance Use and Its Relationship to Depression, Anxiety, and Isolation Among Youth Living With HIV
In a series of three papers, drug use and correlates were examined in youth living with HIV (YLH). Amphetamine use, other HIV-related risk acts, T-cell counts, emotional distress, coping style, and symptoms of HIV were examined in 337 HIV+ youth aged 13 to 24 (20% female; 22% African American, 27% Anglo, 35% Latino) from four cities (LA, NY, San Francisco, and Miami). One third of youth were found to have engaged in amphetamine use in their lifetime, and 21% of youths reported current use (i.e. in the last three months). Compared to non-users, users initiated other drug use at younger ages, used more types of drugs, reported more emotional distress, and employed escape coping significantly more often. Substance use pervaded the lives of these YLH. Among this sample, males had used more drugs, more often, and for longer periods than females. However, there had been major reductions in use. Being male, having high emotional distress, and having fewer negative social supports were significantly associated with greater reductions in substance use. The longer an individual had been diagnosed seropositive tended to be associated with reductions in use (p=.06). Compared to non-users, users also had more sexual partners and more sexual encounters. While users and non-users do not differ on physical symptoms or whether they have been diagnosed with AIDS, users of amphetamines report significantly higher T-cell counts than non-users. Despite poor psychosocial functioning, amphetamine users were found to have higher T-cell counts than other YLH. The continued high-risk profile of transmission acts among users suggests that preventive interventions must target specific drugs used by YLH. As the number of youths infected with HIV rises, secondary prevention programs are needed to help youths living with HIV meet three goals:
1) increase self-care behaviors, medical adherence, and health-related interactions; 2) reduce transmission acts; and 3) enhance their quality of life. Based on modifications of the social action model, a small group intervention was developed and tested in this population. Rotheram-Borus, M.J., Mann, T., and Chabon, B. Amphetamine Use Among Youths Living with HIV. AIDS Education and Prevention, In Press; Rotheram-Borus, M.J., Murphy, D.A., Swendeman, D., Chao, B., Chabon, B., Zhou, S., and Birnbaum, J. Substance Use and its Relationship to Depression, Anxiety, and Isolation Among Youth Living with HIV. International Journal of Behavioral Medicine, In Press; Rotheram-Borus, M.J., and Miller, S. Secondary Prevention for Youths Living with HIV. AIDS Care, 10(1), pp. 17-34. 1998.
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