Methadone Detoxification Programs Research Articles

Opioid overdose in the age of fentanyl: Risk factor differences among subpopulations of overdose survivors

BackgroundAlthough fentanyl is the drug most frequently implicated in overdose deaths, the association between overdose risk and attitudes and behaviors surrounding fentanyl in opioid-using communities has remained understudied. Possible subpopulation differences in fentanyl-related overdose risk remain equally unexamined. This paper addresses these gaps by exploring the association between overdose and fentanyl-related attitudes/behaviors in three subpopulations of overdose survivors. MethodsIn this cross-sectional study, we sampled 432 individuals who currently or recently used opioids from New Jersey methadone and acute residential detoxification programs. Using multinomial regression analysis, we compared overdose risk factors, including fentanyl-related attitudes/behaviors, of those who never overdosed with three subgroups of overdose survivors who experienced: 1. recent overdoses occurring after, but not before, fentanyl expansion; 2. past overdoses occurring before, but not after, fentanyl expansion; 3. persistent overdoses occurring before and after fentanyl expansion. ResultsForty percent of respondents had knowingly used fentanyl and 38% deliberately sought overdose-implicated drugs. Respondents with persistent overdoses represented under 10% of the sample but accounted for 44% of all lifetime overdoses (x̅ =8.03 vs. 1.71 for the full sample). This was also the only subgroup for whom PTSD (AOR=3.84; 95%CI=1.45–10.16; p=.01) and fentanyl-seeking (AOR=1.50; 95% CI=1.16–1.94; p=.01) were significant overdose risk factors. Those with recent overdoses engaged in frequent drug combining (AOR=2.28; 95% CI=1.19–6.98; p=.05), which could have led to inadvertent fentanyl use. Those with past overdoses were not at overdose risk from fentanyl-seeking or drug combining and had rates of methadone treatment comparable to rates of those with no overdoses. ConclusionHarm reduction strategies will need to address consumers’ evolving drug preferences as fentanyl continues to saturate local drug markets. Targeting comprehensive interventions, including mental health treatment, to the small group of opioid users with longstanding overdose histories may reduce the burden of overdose in opioid-using communities.

Treatment outcome predictors in flexible dose-duration methadone detoxification program.

Methadone detoxification is among the widely used treatment programs for opioid dependence. The aims of this study were to identify which patient baseline factors and treatment regimen features are predictors of the treatment outcome in an outpatient flexible dose-duration methadone detoxification program. We studied 126 opioid dependents in a naturalistic nonexperimental clinical setting. The patients were assessed for baseline demographic characteristics, and drug abuse characteristics. Treatment regimen features were recorded during the program. Successful treatment completion was defined as the last daily dose of methadone being less than 15 mg, negative urine analysis in the last two weeks of treatment, and based on the final clinician-client's decision. Out of 126 patients, 60 patients completed detoxification successfully. Younger age, longer duration of the opioid abuse, and higher subjective opiate intoxication severity before treatment entry were all significantly associated with negative treatment outcome. Among treatment regimen features, higher maximum methadone dose had a marginally significant independent effect on treatment failure. Patients with maximum methadone dose of more than 75 mg per day had around ten times worse success rate when compared to those who received lesser doses. The study findings could be used to predict treatment outcome and prognosis in a more individualized and patient-tailored approach in the real clinical setting. Guideline development for treatment selection and outcome monitoring in addiction medicine based on similar studies could enhance treatment outcome in clinical services.

Using Acceptance and Commitment Therapy During Methadone Dose Reduction: Rationale, Treatment Description, and a Case Report

Many clients who undergo methadone maintenance (MM) treatment for heroin and other opiate dependence prefer abstinence from methadone. Attempts at methadone detoxification are often unsuccessful, however, due to distressing physical as well as psychological symptoms. Outcomes from an MM client who voluntarily participated in an Acceptance and Commitment Therapy (ACT)–based methadone detoxification program are presented. The program consisted of a 1-month stabilization and 5-month gradual methadone dose reduction period, combined with weekly individual ACT sessions. Urine samples were collected twice weekly to assess for use of illicit drugs. The participant successfully completed the program and had favorable drug use outcomes during the course of treatment, and at the 1-month and 1-year follow-ups. Innovative behavior therapies, such as ACT, that focus on acceptance of the inevitable distress associated with opiate withdrawal may improve methadone detoxification outcomes.

A randomized trial of 6-month methadone maintenance with standard or minimal counseling versus 21-day methadone detoxification

Background Important questions remain regarding the necessary duration and intensity for methadone treatment to be effective. Methods As part of a clinical trial of tuberculosis chemoprophylaxis [Batki, S.L., Gruber, V.A., Bradley, J.M., Bradley, M., Delucchi, K., 2002. A controlled trial of methadone treatment combined with directly observed isoniazid for tuberculosis prevention in injection drug users. Drug Alcohol Depend. 66 283–293. doi:10.1016/S0376-8716(01)00208-3], patients with opioid dependence were recruited from an outpatient 21-day methadone detoxification program and were randomly assigned to one of three treatment conditions: (1) continuation in 21-day methadone detoxification; (2) transfer to 6-month methadone maintenance with only minimal counseling; or (3) transfer to 6-month methadone maintenance with standard twice monthly counseling and as-needed social work and psychiatric services. Both the 6-month maintenance treatments were followed by 1.5 months of detoxification. Urine drug tests and self-report measures were collected at baseline, months 1–6, and month 8.5. Results Compared to 21-day methadone detoxification, 6-month methadone maintenance with either minimal or standard counseling resulted in fewer opiate positive urine tests and days of self-reported heroin and alcohol use. There was no change in cocaine use or other outcome measures. The increased counseling available in the standard counseling condition did not appear to reduce heroin use further than the minimal counseling condition, in contrast to the effect found for more structured counseling in long-term methadone maintenance (McLellan et al., 1993). Conclusions Six months of methadone maintenance, even with minimal counseling, reduces heroin and alcohol use more than 21-day methadone detoxification.

Drug Treatment Outcomes for Persons on Waiting Lists

This study examined treatment access and outcomes for persons placed on drug abuse treatment waiting lists. Participants (n = 170) were recruited when they entered either a methadone detoxification program or a day treatment program, and were waiting for methadone maintenance or residential treatment, respectively. Participants were interviewed at baseline and 2-months follow-up. Excluding the index treatment episode, 73% received some treatment during the follow-up period. Mixed effects regression was used to compare short-term outcomes for clients who did and did not enter treatment following the index episode. We found increased drug problems, over time, for all participants. Those enrolled in treatment at follow-up reported higher employment problems (collapsed across time) compared with those not in treatment. Last, participants enrolled in any subsequent treatment showed a decrease in psychiatric problems over time, while those not enrolled in subsequent treatment showed an increase in psychiatric problems. Participants who entered treatment within 60 days after being placed on a waiting list showed improvement on psychiatric measures but not on substance abuse measures.

Violence and aggression in the Drug Treatment Centre Board.

We sought to determine the prevalence of and the factors associated with violent and aggressive incidents among clients attending an out-patient methadone stabilisation and detoxification programme in Dublin. We retrospectively examined all incident report forms over a two-year period. We also obtained information on demographics, main drug of abuse, timing and location of the incident as well as psychiatric and physical comorbidity among the perpetrators from case note review. Two hundred and ninety-five incidents occurred over the study period. The overall rate of violence and aggression was 85 per 1,000 clients attending the centre per year. Most incidents involved verbal abuse. Females were significantly more likely to be involved in assaults compared to males. A high proportion of clients (80%) who were physically aggressive tested positive for benzodiazepine medication. Levels of recorded violence have remained stable however racial abuse has increased in recent years. The relatively low overall rate of violence suggests that existing measures have helped reduce the number of aggressive and violent incidents in the centre. Most of the victims were either doctors, nursing staff or general assistants. This finding reflected their respective roles in the centre, which included limit setting and dealing with positive drug screens among clients.

Profiles of Self‐Reported HIV‐Risk Behaviors Among Injection Drug Users in Methadone Maintenance Treatment, Detoxification, and Needle Exchange Programs

Injection drug use has accounted for more than one third of acquired immune deficiency syndrome cases in the United States. The purpose of this study was to compare the demographic characteristics, types, and frequency of human immunodeficiency virus (HIV)-risk behaviors among injection drug users (IDUs) recruited from a needle exchange program (NEP), methadone maintenance treatment (MMT), and detoxification (detox) program. A cross-sectional, correlational design was used to determine whether the selected HIV-risk behaviors and demographic characteristics of IDUs varied by site of recruitment. SAMPLE AND MEASUREMENTS: Confidential questionnaires were completed by 445 IDUs in Philadelphia, Pennsylvania. Data analysis revealed that HIV sexual and injection-risk behavior varied by recruitment site. Subjects recruited from the NEP were more likely to engage in HIV-risk behaviors than subjects recruited from the MMT or detox sites. Interventions occurring in program and treatment sites need to be sensitive to various demographic characteristics and behaviors if they are to reach those at highest risk of HIV infection. Targeting HIV prevention interventions based upon risk group membership alone (e.g. IDUs) fails to address the distinct risk behaviors and demographic characteristics of enrollees in different programs.

Drug Treatment Needs of Hispanic Drug Users in Long Beach, California

The objective of this study is to investigate differences between Hispanic and non-Hispanic drug users in Long Beach, CA, with respect to drug use, HIV risk behaviors, and drug treatment experience and to explore the dissimilarities between Hispanic drug users who identify their family origin as Mexican American compared to those who identify their family origin as Mexican. We recruited 1,728 drug users into an HIV risk reduction intervention; of these, 404 were Hispanic. The Risk Behavior Assessment (RBA) was used to collect information on demographics, drug and sex risk behaviors, and drug treatment experience. Hispanic drug users are significantly more likely to inject drugs than non-Hispanic drug users and were found to have a higher mean number of injections in the last 30 days. Hispanic drug users were more likely to have taken part in drug treatment programs, specifically methadone detoxification and maintenance programs. Self-identified Mexican drug users were less likely to have ever attended a drug treatment program than were Mexican-American drug users. Greater availability of drug treatment programs for monolingual and bilingual Hispanic injectors is needed.

Methadone at tapered doses for the management of opioid withdrawal.

Despite widespread use in many countries of tapered methadone for detoxification from opiate dependence, the evidence of efficacy to prevent relapse and promote lifestyle change has not been systematically evaluated. To determine whether tapered methadone is effective to manage withdrawal from opioids. We searched: the Cochrane Controlled Trials Register (Issue 1, 2000), MEDLINE (OVID 1966-2000), EMBASE (1980-2000); scan of reference list of relevant articles; personal communication; conference abstracts; unpublished trials from pharmaceutical industry; Internet (NIDA, Clinical Trials.org, BMJ). All randomised controlled trials which focus on the use of tapered methadone (length of treatment max 30 days) versus all other pharmacological detoxification treatments, placebo and different modalities of methadone detoxification programs for the treatment of opiate withdrawal. Trials including patients with additional diagnoses such as benzodiazepine dependence were also eligible. One reviewer (LA) assessed studies for inclusion and undertook data extraction. Inclusion decisions and the overall process were confirmed by consultation between reviewers. Qualitative assessments of the methodology of eligible studies were carried out using validated checklists. Where possible analysis was carried out according to the "intention to treat" principles. 20 studies were included in the review, with 1357 people randomised. 10 studies compared methadone with adrenergic agonists, 7 studies compared different modalities of methadone detoxification, 2 studies compared methadone with other opioid agonists, 1 study compared methadone with chlordiazepoxide one with placebo. The conclusions of the 10 studies that compared methadone with adrenergic agonists showed no substantial clinical difference of the two treatments in terms of retention in treatment, degree of discomfort and detoxification success rates. The conclusions of the 6 studies that compare different methadone reduction schedules, showed that different types of methadone withdrawal schedule produce different responses in terms of time course of withdrawal, the severity of withdrawal response and possibly in terms of subsequent engagement with treatment. Regarding the studies that compare methadone with other opioid agonists, in Sorensen 1982 methadyl acetate performed similarly to methadone on most process and outcome measures, while in Tennant 1975, methadone reduced severity of withdrawal and had fewer drop-outs than did a propoxyphene group. In Drummond 1989, using chlordiazepoxide vs methadone, the results suggest that the two drugs had similar results in terms of overall effectiveness.San 1992 compared methadone with placebo and found more severe withdrawal and more drop outs in the placebo group. The results indicate that tapered methadone and other medications used in the included studies are effective in the treatment of the heroin withdrawal syndrome, although symptoms experienced by subjects differed according to the medication used and the program adopted. It seems that regardless of which medication is selected for heroin detoxification, the rates of subsequent heroin abstinence are about equal. This suggests that the medications are similar in terms of overall effectiveness. Improvements were achieved when other services such as counseling and other supporting services were offered contemporaneously with detoxification. Data from literature are hardly comparable; programs vary widely with regard to duration, design and treatment objectives, impairing the application of meta-analysis. Results of many outcomes could not be summarised because they were presented either in graphical form or provided only statistical tests and p-values. For most studies standard deviation for continuous variables were not provided. The studies included in this review confirm that slow tapering with temporary substitution of long acting opioids, accompanied by medicaopioids, accompanied by medical supervision and ancillary medications can reduce withdrawal severity. Nevertheless the majority of patients relapsed to heroin use. However this cannot be considered a goal for a detoxification as heroin dependence is a chronic, relapsing disorder and the goal of detoxification should be to remove or reduce dependence on heroin in a controlled and human fashion and not a treatment for heroin dependence.

Alpha 1-acid glycoprotein (AAG) and serum protein binding of methadone in heroin addicts with abstinence syndrome.

To quantify serum protein levels and protein-binding of methadone in vitro in heroin-addicted patients showing objective signs of heroin abstinence. Serum samples were obtained from patients (n = 27) hospitalized to participate in a methadone detoxification program and from healthy volunteers (n = 21). The severity of the abstinence syndrome was assessed before blood sampling using a standardized scale. Concentrations of both albumin and alpha1-acid glycoprotein (AAG) were measured in all serum samples. The protein-binding of alpha1-methadone was determined by the ultrafiltration technique and the unbound concentration was measured by liquid scintillation counting. The mean of the AAG concentrations was significantly increased in patients showing signs of withdrawal while the albumin concentrations did not change. Also, the unbound methadone was significantly decreased in this group when compared to the control. A positive correlation (Pearson r = 0.48; p < 0.005) indicates that AAG levels rise during abstinence as the score of withdrawal symptoms increases. Additionally, pooled data from all individuals show the binding of methadone to be related to AAG (r = 0.46; p < 0.05) levels and not to albumin. The observed changes in protein-binding in abstinence individuals suggest the need for increased dosages of methadone when such patients are treated. Levels of AAG or protein-binding appear to be components of the interindividual variance observed in the response to methadone treatment, hence these variables could be included in future kinetic and dynamic studies.

Homelessness and Gender in Out-of-Treatment Drug Users

This study examines 5225 out-of-treatment crack users and drug injectors drawn from five different geographic areas to examine selected factors associated with homelessness. Of these crack users, 27% considered themselves undomiciled, and 60% had previously entered some type of drug treatment. Logistic regression found that substance abusers who were married, female, and persons of color were less likely to be without a home when other variables were controlled. Trading sex for money and perceived chance of getting acquired immunodeficiency syndrome (AIDS) were associated positively with homelessness, while participating in methadone detoxification and methadone maintenance programs seemed to offer some protection from homelessness.

A pilot study to determine the usefulness of the urinary excretion of methadone and its primary metabolite (EDDP) as potential markers of compliance in methadone detoxification programs.

Fourteen subjects (selected on the basis of compliance with the methadone-maintenance program prescribed by the consultant psychiatrist in charge of their treatment) undergoing opiate detoxification by methadone-replacement therapy were studied to determine if a relationship exists between the dose of methadone prescribed and the urinary excretion of methadone and/or its primary metabolite, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP). After the derivation of this relationship, it was hoped that the urinary concentrations of methadone and/or EDDP could be used as a noninvasive technique to monitor the methadone compliance of 56 drug abusers. Despite statistically significant correlations (p<0.001) between methadone dose and urine concentrations of methadone and EDDP, the large variation in concentrations measured in the urine of drug abusers negated the possibility of any clear-cut relationship being confirmed. However, it may be possible to use excretion data to monitor individual compliance but only through long-term monitoring of individual subjects to establish their own intraindividual variation in excretion patterns.

A lasting public health response to an outbreak of HIV infection in a Scottish prison?

Between April and June 1993, 8 cases of acute clinical hepatitis B infection and 2 seroconversions to HIV infection were detected among drug injecting inmates of HM Prison Glenochil in Scotland. To prevent the further spread of infection, an initiative which involved counselling and voluntary attributable HIV testing was conducted over a 10-day period commencing at the end of June. A team of 18 counsellors and phlebotomists was brought together rapidly as part of a unique organizational exercise in the field of public health. Fourteen cases of HIV infection were identified of which 13 were almost certainly infected in Glenochil. Following the exercise, a range of harm reduction measures for injecting prisoners was introduced; these included the availability of hepatitis B vaccine, provision of bleach tablets which could be used to clean injecting equipment, a methadone detoxification programme, increased training for prison officers and improved access to drug and harm minimization counselling for inmates. By mid-1996 all these measures had been sustained and several could be found in many other prisons throughout Scotland. Follow-up investigations showed no evidence of epidemic spread of HIV during the 12 months after the initiative. While the frequency of injecting and needle/syringe sharing may have decreased over the last 3 years, these activities are still being reported and it is highly likely that transmissions of bloodborne infections, in particular hepatitis C, continue to occur. The surveillance and prevention of infections associated with injecting drug use in the prison setting remain a high public health priority.

Wound botulism associated with black tar heroin among injecting drug users.

Wound botulism (WB) is a potentially lethal, descending, flaccid, paralysis that results when spores of Clostridium botulinum germinate in a wound and elaborate neurotoxin. Since 1988, California has experienced a dramatic increase in WB associated with injecting "black tar" heroin (BTH), a dark, tarry form of the drug. To identify risk factors for WB among injecting drug users (IDUs). Case-control study based on data from in-person and telephone interviews. Case patients (n=26) were IDUs who developed WB from January 1994 through February 1996. Controls (n=110) were IDUs newly enrolled in methadone detoxification programs in 4 counties. Factors associated with the development of WB. Among the 26 patients, the median age was 41.5 years, 15 (58%) were women, 14 (54%) were non-Hispanic white, 11 (42%) were Hispanic, and none were positive for the human immunodeficiency virus. Nearly all participants (96% of patients and 97% of controls) injected BTH, and the mean cumulative dose of BTH used per month was similar for patients and controls (27 g and 31 g, respectively; P=.6). Patients were more likely than controls to inject drugs subcutaneously or intramuscularly (92% vs 44%, P<.001) and used this route of drug administration more times per month (mean, 67 vs 24, P<.001), with a greater cumulative monthly dose of BTH (22.3 g vs 6.3 g, P<.001). A dose-response relationship was observed between the monthly cumulative dose of BTH injected subcutaneously or intramuscularly and the development of WB (chi2 for linear trend, 26.5; P<.001). In the final regression model, subcutaneous or intramuscular injection of BTH was the only behavior associated with WB among IDUs (odds ratio, 13.7; 95% confidence interval, 3.0-63.0). The risk for development of WB was not affected by cleaning the skin, cleaning injection paraphernalia, or sharing needles. Injection of BTH intramuscularly or subcutaneously is the primary risk factor for the development of WB. Physicians in the western United States, where BTH is widely used, should be aware of the potential for WB to occur among IDUs.

A lasting public health response to an outbreak of HIV infection in a Scottish prison?

Summary: Between April and June 1993, 8 cases of acute clinical hepatitis B infection and 2 seroconversions to HIV infection were detected among drug injecting inmates of HM Prison Glenochil in Scotland. To prevent the further spread of infection, an initiative which involved counselling and voluntary attributable HIV testing was conducted over a 10-day period commencing at the end of June. A team of 18 counsellors and phlebotomists was brought together rapidly as part of a unique organizational exercise in the field of public health. Fourteen cases of HIV infection were identified of which 13 were almost certainly infected in Glenochil. Following the exercise, a range of harm reduction measures for injecting prisoners was introduced; these included the availability of hepatitis B vaccine, provision of bleach tablets which could be used to clean injecting equipment, a methadone detoxification programme, increased training for prison officers and improved access to drug and harm minimization counselling for inmates. By mid-1996 all these measures had been sustained and several could be found in many other prisons throughout Scotland. Follow-up investigations showed no evidence of epidemic spread of HIV during the 12 months after the initiative. While the frequency of injecting and needle/syringe sharing may have decreased over the last 3 years, these activities are still being reported and it is highly likely that transmissions of bloodborne infections, in paticular hepatitis C, continue to occur. The surveillance and prevention of infections associated with injecting drug use in the prison setting remain a high public health priority.

Interrogative suggestibility in opiate users.

The present study investigated interrogative suggestibility in opiate users. A group of patients undergoing a methadone detoxification programme in an in-patient drug treatment unit (Detox group, n = 21), and a group of residents who had come off drugs and were no longer suffering from withdrawal syndrome (Rehab group, n = 19) were compared on interrogative suggestibility and various other psychological factors. Significant differences were found between the two groups, with the Detox group having more physical and psychological problems, and a higher total suggestibility score in comparison with the Rehab group. These findings are discussed in relation to the context of police interrogations and the reliability of confessions made by suspects and witnesses dependent on opiates.

Prevalence and Pattern of Benzodiazepine Abuse and Dependence Among Patients in a Methadone Detoxification Programme: A Repeated Cross-Sectional Analysis (Benzodiazepine Abuse Among Opiate Addicts)

This study was a repeated cross-sectional analysis of records of admissions to an in-patient methadone detoxification programme in two twelve-month matched periods, four years apart. The objectives were to identify changes in prevalence and pattern of benzodiazepine abuse and dependence among opiate addicts between the first (baseline) and second (follow-up) study periods. Prevalence rate of benzodiazepine abuse increased from 11.8% at baseline to 36% at follow-up, and the rates for benzodiazepine dependence at baseline and follow-up were 4.5% and 15.4% respectively. The following significant changes between the two study periods were also observed: Age of first benzodiazepine use, temazepam use, combined use of multiple benzodiazepines, injecting behaviour, use of barbiturates and cannabis, severity of dependence, and rate of treatment completion. The need to routinely assess methadone detoxification patients for benzodiazepine abuse and dependence on admission is underscored.

The relationship of counselor and peer alliance to drug use and HIV risk behaviors in a six-month methadone detoxification program

The purpose of this study was to examine the relationship of treatment outcomes in opioid detoxification to levels of counselor and peer alliance. Forty-one subjects were recruited from a larger, 180-day study of psychosocial treatment. Beginning at day 90 subjects completed monthly measures of alliance. Outcome measures included treatment retention, drug use, and self-reported HIV risk. Measures of alliance were found to be internally consistent and moderately stable over time. During the final 30 days of the methadone taper, higher levels of both types of alliance were associated with less use of illicit opioids. Alliance with counselor was associated with less frequent needle sharing. For subjects who could be located for 30-day follow-up, greater alliance with peers was associated with more frequent HIV (sexual) risk behaviors. Results suggest that treatment outcome may be improved through approaches that address a patient's alliance with both counselor and peers.

Tuberculosis Transmission in Methadone Maintenance Programs

To the Editor. —We recently reported 1 that among homeless injection drug users in San Francisco, Calif, there was an increased risk for tuberculosis (TB) infection among those who had ever been in a methadone program. At that time we were unable to distinguish subjects who had been in methadone maintenance programs from those who had been in short-term (≤21 days) methadone detoxification only. We have now reexamined this question in a large group of 2774 homeless and unstably housed persons. A total of 632 subjects had skin test results, were negative for the human immunodeficiency virus (HIV), and had used injection drugs. One hundred of these had been in methadone treatment programs. We grouped the 632 subjects as follows: (1) those who had never been in any methadone treatment programs, (2) those who had ever been in methadone detoxification programs only, and (3) those who had ever been in

HIV seroconversion in intravenous drug users in San Francisco, 1985-1990.

To examine the HIV seroconversion rate, risk factors for seroconversion, and changes in risk behavior over time in intravenous drug users (IVDU) in San Francisco, 1985-1990. Observational study. All methadone maintenance and 21-day methadone detoxification programs in San Francisco. A total of 2351 heterosexual IVDU, of whom 681 were seronegative at first visit and seen at least twice ('repeaters'). HIV seroconversion rates, risk factors for seroconversion, and changes in behavior. The HIV seroconversion rate in repeaters was 1.9% per person-year (ppy) of follow-up [2.1% in women versus 1.7% in men (not significant); 4% in African Americans versus 1% in whites (P = 0.006); 3.9% ppy in the first third of the study, 1.2% in the second (P = 0.007), and 1.9% in the last (not significant)]. Risk factors for seroconversion were five or more sexual partners per year [hazard ratio (HR) = 2.6; P = 0.02], use of shooting gallery ever (HR = 2.9; P = 0.02), and less than 1 year (lifetime) in methadone maintenance (HR = 2.7; P = 0.02). Self-reported intravenous cocaine use fell from 33 to 15% over 5 years, shooting gallery use fell from 19 to 6%, and the proportion with five or more sexual partners fell from 25 to 10%. Bleach use rose to 75% of needle-sharers. The 1985-1990 HIV seroconversion rate in IVDU (1.9% ppy) was comparable to that in San Francisco cohorts of homosexual men (1.4% ppy). A decline in HIV seroconversion coincided with changes in risk behavior. Stable attendance of methadone maintenance was highly protective: the seroconversion rate in subjects with 1 year or more in methadone was 12% ppy.