Risk factors for methadone outside treatment programs: implications for HIV treatment among injection drug users

The impact of relaxing restrictions on take-home doses during the COVID-19 pandemic on program effectiveness and client experiences in opioid agonist treatment: a mixed methods systematic review

BACKGROUND

The COVID-19 pandemic led to an unprecedented relaxation of restrictions on take-home doses in opioid agonist treatment (OAT). We conducted a mixed methods systematic review to explore the impact of these changes on program effectiveness and client experiences in OAT.

METHODS

The protocol for this review was registered in PROSPERO (CRD42022352310). From Aug.-Nov. 2022, we searched Medline, Embase, CINAHL, PsycInfo, Web of Science, Cochrane Register of Controlled Trials, and the grey literature. We included studies reporting quantitative measures of retention in treatment, illicit substance use, overdose, client health, quality of life, or treatment satisfaction or using qualitative methods to examine client experiences with take-home doses during the pandemic. We critically appraised studies using the Mixed Methods Appraisal Tool. We synthesized quantitative data using vote-counting by direction of effect and presented the results in harvest plots. Qualitative data were analyzed using thematic synthesis. We used a convergent segregated approach to integrate quantitative and qualitative findings.

RESULTS

Forty studies were included. Most were from North America (23/40) or the United Kingdom (9/40). The quantitative synthesis was limited by potential for confounding, but suggested an association between take-home doses and increased retention in treatment. There was no evidence of an association between take-home doses and illicit substance use or overdose. Qualitative findings indicated that take-home doses reduced clients' exposure to unregulated substances and stigma and minimized work/treatment conflicts. Though some clients reported challenges with managing their medication, the dominant narrative was one of appreciation, reduced anxiety, and a renewed sense of agency and identity. The integrated analysis suggested reduced treatment burden as an explanation for improved retention and revealed variation in individual relationships between take-home doses and illicit substance use. We identified a critical gap in quantitative measures of patient-important outcomes.

CONCLUSION

The relaxation of restrictions on take-home doses was associated with improved client experience and retention in OAT. We found no evidence of an association with illicit substance use or overdose, despite the expansion of take-home doses to previously ineligible groups. Including patient-important outcome measures in policy, program development, and treatment planning is essential to ensuring that decisions around take-home doses accurately reflect their value to clients.

The risk assessment of relapse among newly enrolled participants in methadone maintenance treatment: A group-LASSO based Bayesian network study

Background

Relapse is a great barrier to improving the effectiveness of methadone maintenance treatment (MMT). Participants with different treatment durations could vary in their compliance with MMT, which may lead to different levels of relapse risk. This study aims to identify the risk factors for relapse and assess the relapse risk of MMT participants of different treatment durations.

Method

This retrospective study used data collected from seven MMT clinics in Guangdong Province, China, from January 2010 to April 2017. Newly enrolled participants who received 6 (n = 903) and 12 (n = 710) months of consecutive treatment with complete data were included. We selected significant risk factors for relapse through the group lasso regression and then incorporated them into Bayesian networks to reveal relationships between factors and predict the relapse risk.

Results

The results showed that participants who received 6-month treatment had a lower relapse rate (32.0%) than those of 12-month treatment (39.0%, P < 0.05). Factors including personal living status and daily methadone dose were only influential to those who received the 6-month treatment. However, age, age at the initial drug use, HIV infection status, sexual behaviors, and continuous treatment days were common factors of both durations. The highest relapse risk for those after the 6-month treatment was inferred as 66.7% while that of the 12-month treatment was 83.3%. Farmers and those who have high accessibility to MMT services may require additional attention.

Conclusion

It is necessary to implement targeted interventions and education based on the treatment durations of participants to decrease the relapse rate. Meanwhile, those about HIV/sexually transmitted infection prevention and anti-narcotics should be held in the whole process.

Risk factors for prescription drug diversion among people living with HIV: a systematic scoping review

BACKGROUND

In addition to numerous infections and frequent pain constantly affecting people living with HIV (PLWH), various risk factors might contribute to prescription drug diversion. The purpose of the study is to map existing evidence on risk factors contributing to prescription drug diversion among PLWH.

METHODS

Arksey and O'Malley's framework and the recommendation by Levac et al. (2010) guided this study. We searched for relevant literature from the following databases: PubMed; Google Scholar; EBSCOhost (Academic Search Complete, MEDLINE and Newspaper Source), Cochrane, WHO, HIV, ScienceDirect and Open Access Theses and Dissertations. Studies reporting evidence on risk factors contributing to prescription drug diversion and published in the period January 1996 to July 2017 were included. Thematic content analysis was performed to summarize the findings.

RESULTS

The search identified 734 studies. After full-text screening of the eligible studies, risk factors contributing to prescription drug diversion among PLWH were reported in 20 included studies. It was found that there is limited research on prescription drug diversion among PLWH in low-middle-income countries (LMICs). Risk factors contributing to prescription drug diversion were being a substance user or substance dependent; being male; young in age; being stigmatized; not disclosed HIV status; diagnosed with mental health problems; being HIV infected; poor health and well being; being White; being homeless or not owing a home; having low educational level; having history of diversion, misuse or abuse; in possession of addictive prescriptions; being unemployed and living in high neighbourhood disorder.

CONCLUSION

Evidence shows that there is limited research on prescription drug diversion among PLWH in LMICs. The study findings show that the risk factors contributing to prescription drug diversion are related with risk factors for HIV transmission and infection.

PROSPERO REGISTRATION NUMBER

CRD42017074076.

Prescription drug diversion among people living with HIV: a systematic scoping review

OBJECTIVES

Globally, people living with HIV (PLWH) are at greater risk for various infections and chronic pain, therefore, vulnerable to prescription drug diversion which might negatively impact HIV care. The study purpose is to gather evidence on prescription drug diversion among PLWH.

STUDY DESIGN

This is a systematic scoping review.

METHODS

Arksey and O'Malley's framework and recommendation by Levac et al. were used to guide this study. Literature was searched in PubMed, Google Scholar, EBSCOhost (Academic Search Complete, MEDLINE and Newspaper Source) and Open Access Theses and Dissertations. Studies reporting evidence of prescription drug diversion from January 1996 to July 2017 were included. Thematic content analysis was performed to summarize data on the prevalence.

RESULTS

Twenty-nine studies were eligible for data synthesis. Twenty-six studies were conducted in the United States of America (USA), one study in France and two multicountry studies; one study in Kenya and Uganda and the other study in Botswana, Kenya, Malawi, South Africa; Zimbabwe, India, Thailand, Brazil and the USA. Research evidence shows high prevalence of prescription drug diversion for analgesics and antiretroviral drugs; meanwhile, stimulants and erectile dysfunction drugs were the least diverted drugs among PLWH. There is a research gap in low- to middle-income countries (LMICs) investigating prescription drug diversion among PLWH.

CONCLUSION

Our findings reveal that diversion of various prescription drug classes among PWLH exists. There is lack of research in LMICs. We recommend research in LMICs where there is high HIV prevalence.

PROSPERO REGISTRATION NUMBER

CRD42017074076.

Non-prescribed use of methadone and buprenorphine prior to opioid substitution treatment: lifetime prevalence, motives, and drug sources among people with opioid dependence in five Swedish cities

Background

Opioid substitution treatment (OST) with methadone or buprenorphine is the most effective means of treating opioid dependence. If these substances are used by people who are not undergoing OST, they can however carry serious risks. This article examines the lifetime prevalence, motives, and drug sources for such use, as well as geographical differences in these variables.

Methods

Structured interviews were conducted with 411 patients from 11 OST clinics in five Swedish cities. The researchers carried out 280 interviews on-site, while 131 interviews were conducted by specially trained patients through privileged access interviewing. Data were analyzed by frequency and average calculations, cross-tabulations, and χ² tests.

Results

The lifetime prevalence of non-prescribed use was 87.8% for methadone, 80.5% for buprenorphine, and 50.6% for buprenorphine/naloxone. Pseudo-therapeutic motives—avoiding withdrawal symptoms, staying clean from heroin, detoxification, or taking care of one’s own OST—were commonly cited as driving the use, while using the drugs for euphoric purposes was a less common motive. Most respondents had bought or received the substances from patients in OST, but dealers were also a significant source of non-prescribed methadone and buprenorphine. Geographical differences of use, motives, and sources suggest that prescription practices in OST have a great impact on which substances are used outside of the treatment.

Conclusions

Experiences of non-prescribed use of methadone and buprenorphine are extremely common among those in OST in southern Sweden. As the use is typically driven by pseudo-therapeutic motives, increased access to OST might decrease the illicit demand for these substances. Buprenorphine/naloxone has a lower abuse potential than buprenorphine and should therefore be prioritized as the prescribed drug. Supervised dosage and other control measures are important provisions in the prevention of drug diversion and non-prescribed use among people not undergoing OST.

Diversion of methadone and buprenorphine from opioid substitution treatment: the importance of patients' attitudes and norms

AIMS

Methadone and buprenorphine diversion by patients in opioid substitution treatment (OST) is a poorly understood phenomenon. We study the norms and attitudes on diversion among OST patients, including the role these norms and attitudes play as diversion risk factors. We also study whether perceived quality of care, social bonds to treatment staff, and deterrence can be associated with diversion.

METHODS

Structured interviews were conducted with 411 patients from eleven OST programs. In total, 280 interviews were done on site by the researchers, while 131 interviews were conducted through peer interviewing by specially trained patients. The data was analyzed through frequency- and averages-calculations, cross-tabulations, and logistic regression analysis.

RESULTS

Most patients consider diversion as mostly positive (83.7%), morally right (76.8%), and without any significant risk of detection (66.9%). Individual differences in norms and risk perceptions may play a role in explaining variations in diversion; patients who consider it right to share medication with friends report higher treatment-episode diversion than other patients (OR 1.455, p = 0.016). Patients who perceive control measures as effective report lower diversion than other patients (OR = 0.655, p = 0.013). Furthermore, data indicate that patients who are satisfied with the care and service are less prone to engage in diversion. Social bonds with treatment staff seem to be less importance.

CONCLUSIONS

The norm system described by patients resemble Bourgois' 'moral economy of sharing' concept-not sharing drugs with friends in withdrawal is considered unethical. Efforts to decrease diversion may focus on lifestyle-changing interventions, and reducing black market demand for illicit medications by expanding access to treatment.

Illicit use of opioid substitution drugs: prevalence, user characteristics, and the association with non-fatal overdoses

BACKGROUND AND AIMS

Diversion of opioid substitution drugs (OSD) is of public concern. This study examined the prevalence, frequency, and predictors of illicit OSD use in a group of injecting drug users (IDUs) and assessed if such use was associated with non-fatal overdoses.

METHODS

Semi-annual cross-sectional interviews conducted in Oslo, Norway (2006-2013), from 1355 street-recruited IDUs. Hurdle, logistic, and multinomial regression models were employed.

RESULTS

Overall, 27% reported illicit OSD use in the past four weeks; 16.8% methadone, 12.5% buprenorphine, and 2.9% both drugs. Almost 1/10 reported at least one non-fatal overdose in the past four weeks, and roughly 1/3 reported such experience in the past year. Use of additional drugs tended to be equally, or more prevalent among illicit OSD users than other IDUs. In terms of illicit OSD use being a risk factor for non-lethal overdoses, our results showed significant associations only for infrequent buprenorphine use (using once or less than once per week). Other factors associated with non-fatal overdoses included age, education, homelessness, as well as the benzodiazepines, stimulants, and heroin use.

CONCLUSIONS

Users of diverted OSD may represent a high-risk population, as they used more additional drugs and used them more frequently than other IDUs. However, illicit OSD use may be less harmful than previously assumed. After accounting for an extensive set of covariates, only infrequent illicit buprenorphine use, but not methadone use, was associated with non-fatal overdoses.

Prevalence and correlates of street-obtained buprenorphine use among current and former injectors in Baltimore, Maryland

OBJECTIVES

There are few systematic assessments of street-obtained buprenorphine use from community-based samples in the United States. The objective of this study was to characterize the prevalence, correlates, and reasons for street-obtained buprenorphine use among current and former injection drug users (IDUs) in Baltimore, Maryland.

METHODS

In 2008, participants of the ALIVE (AIDS Linked to the IntraVenous Experience) study, a community-based cohort of IDUs, were administered a survey on buprenorphine. Street-obtained buprenorphine represented self-reported use of buprenorphine obtained from the street or a friend in the prior three months.

RESULTS

Six hundred and two respondents were predominantly male (65%), African-American (91%), and 30% were HIV-positive. Overall, nine percent reported recent street-obtained buprenorphine use, and only 2% reported using to get high. Among active opiate users, 23% reported recent use of street-obtained buprenorphine. Use of buprenorphine prescribed by a physician, injection and non-injection drug use, use of street-obtained methadone and prescription opiates, homelessness, and opioid withdrawal symptoms were positively associated, while methadone treatment, health insurance, outpatient care, and HIV-infection were negatively associated with recent street-obtained buprenorphine use in univariate analysis. After adjustment, active injection and heroin use were positively associated with street-obtained buprenorphine use. Ninety-one percent reported using street-obtained buprenorphine to manage withdrawal symptoms.

CONCLUSIONS

While 9% reported recent street-obtained buprenorphine use, only a small minority reported using buprenorphine to get high, with the majority reporting use to manage withdrawal symptoms. There is limited evidence of diversion of buprenorphine in this sample and efforts to expand buprenorphine treatment should continue with further monitoring.

Illicit use of methadone and buprenorphine among adolescents and young adults in Sweden

BACKGROUND

Illicit use of methadone and buprenorphine has been described as a growing problem in Sweden in recent years, and has been associated with an increased drug-related mortality. Critics claim that the substances have become popular among adolescents and that they function as a gateway to heroin use. The aim of this study is to investigate, firstly, the extent to which illicit use of methadone and buprenorphine occurs among adolescents and young adults in Sweden, and secondly, at what stage in a user's drug career these substances tend to appear.

METHODS

The study is based on surveys and structured interviews on drug use among various populations of young people, in addition to qualitative interviews with 86 informants who, in their professional capacity, encounter adolescents or young adults who are using illicit drugs.

RESULTS

Illicit use of methadone and buprenorphine is rare among young people in Sweden. According to high school surveys, less than 0.1% have tried these substances. Among young drug users in general, few have tried the substances, and there is nothing to indicate that they act as gateway drugs. Among adolescents and young adults with severe drug problems, however, the illicit use of methadone and buprenorphine is more common (54% in a compulsory care sample). These substances normally enter the drug career late, and few use them as their main drug of choice. Other prescription drugs, like benzodiazepines and tramadol, are used by adolescents to a far greater extent. Diversion and illicit use of methadone and buprenorphine is not seen as a serious problem by the professionals interviewed. A general view is that the substances are mainly used by people with a heroin or polydrug addiction, often for "self-medication" purposes. However, several informants express concern that methadone and buprenorphine may cause fatalities among young drug users without an opioid tolerance.

CONCLUSIONS

Illicit use of methadone and buprenorphine among young drug users is not a widespread problem in Sweden. Harm-reduction measures should target drug users with more severe problems, among whom illicit use of methadone and buprenorphine is more common and pose a medical risk. Illicit use of other prescription drugs, which are less controlled and more widely used by young people, is an important issue for further research.

The nature of methadone diversion in England: a Merseyside case study

Background

Methadone maintenance treatment (MMT) is a key element in treatment for opiate addiction; however concerns about the diversion of methadone remain. More current empirical data on methadone diversion are required. This research investigated the market for diverted methadone in Merseyside, UK, in order to provide a case study which can be transferred to other areas undertaking methadone maintenance treatment on a large scale.

Methods

Questionnaires were completed (in interview format) with 886 past year users of methadone recruited both in and out of prescribing agencies. Topic areas covered included current prescribing, obtaining and providing methadone, reasons for using illicit methadone and other drug use.

Results

Large proportions of participants had obtained illicit methadone for use in the past year with smaller proportions doing so in the past month. Proportions of participants buying and being given methadone were similar. Exchange of methadone primarily took place between friends and associates, with 'dealers' rarely involved. Gender, age, whether participant's methadone consumption was supervised and whether the aims of their treatment had been explained to them fully, influenced the extent to which participants were involved in diverting or using diverted methadone.

Conclusion

Methadone diversion is widespread although drug users generally do not make use of illicit methadone regularly (every month). The degree of altruism involved in the exchange of methadone does not negate the potential role of this action in overdose or the possibility of criminal justice action against individuals. Treatment agencies need to emphasise these risks whilst ensuring that treatment aims are effectively shared with clients to ensure adherence to treatment.

Correlates of non-medical prescription drug use among a cohort of injection drug users in Baltimore City

Despite reports of increasing non-medical prescription drug use, relatively few studies have systematically evaluated the prevalence and correlates of non-medical prescription drug use, particularly in populations that might be especially vulnerable (e.g., injection drug users [IDUs]). We examined factors associated with non-medical prescription drug use among a community-based cohort of current and former IDUs in Baltimore (The ALIVE Study). We conducted a cross-sectional analysis of data from cohort participants that responded to a survey that included questions on non-medical prescription drug use between 2005-06 (n=1320). Non-medical prescription drug use was considered to be use of any of the following: Opiates (Oxycontin, Percocet), Benzodiazepines or Clonidine, purchased on the street and taken orally within the last six months. Data on other covariates of interest (e.g., demographics, substance use, general health) was obtained through a standardized interview. The median age was 46 years; 66% were male, 85% were African-American. Twenty one percent reported any non-medical prescription drug use; 12% reported using more than one drug. Non-medical use of opiates was most common (17%). In multivariate analysis, non-medical prescription drug use was significantly associated with Caucasian race (prevalence ratio [PR]: 1.79), self-reported bodily pain (PR: 1.58), hazardous alcohol use (PR: 1.47), marijuana use (PR: 1.65), non-injection cocaine/heroin use (PR: 1.70), diverted use of buprenorphine (PR: 1.51) or methadone (PR: 2.51), and active injection drug use (PR: 3.50; p<0.05 for all). The association between bodily pain and non-medical prescription drug use was stronger among persons that were not using substances (marijuana, injecting drugs, snorting/smoking heroin, cocaine, using crack) as compared to those using these substances. The high prevalence of non-medical prescription drug use among this population warrants further research and action. Information on the risks of nonmedical prescription drug use especially overdose, should be incorporated into interventions targeted at IDUs.

Uses of diverted methadone and buprenorphine by opioid-addicted individuals in Baltimore, Maryland

This study examined the uses of diverted methadone and buprenorphine among opiate-addicted individuals recruited from new admissions to methadone programs and from out-of-treatment individuals recruited from the streets. Self-report data regarding diversion were obtained from surveys and semi-structured qualitative interviews. Approximately 16% (n = 84) of the total sample (N = 515) reported using diverted (street) methadone two-three times per week for six months or more, and for an average of 7.8 days (SD = 10.3) within the past month. The group reporting lifetime use of diverted methadone as compared to the group that did not report such use was less likely to use heroin and cocaine in the 30 days prior to admission (ps <.01) and had lower ASI Drug Composite scores (p <.05). Participants in our qualitative sub-sample (n = 22) indicated that street methadone was more widely used than street buprenorphine and that both drugs were largely used as self-medication for detoxification and withdrawal symptoms. Participants reported using low dosages and no injection of either medication was reported.

Methadone metabolism and clearance are induced by nelfinavir despite inhibition of cytochrome P4503A (CYP3A) activity

BACKGROUND

Methadone plasma concentrations are decreased by nelfinavir. Methadone clearance and the drug interactions have been attributed to CYP3A4, but actual mechanisms of methadone clearance and the nelfinavir interaction are unknown. We assessed nelfinavir effects on methadone pharmacokinetics and pharmacodynamics, intestinal and hepatic CYP3A4/5 activity, and intestinal P-glycoprotein transport activity. CYP3A4/5 and transporters were assessed using alfentanil and fexofenadine, respectively.

METHODS

Twelve healthy HIV-negative volunteers underwent a sequential crossover. On three consecutive days they received oral alfentanil plus fexofenadine, intravenous alfentanil, and intravenous plus oral methadone. This was repeated after nelfinavir. Plasma and urine analytes were measured by mass spectrometry. Opioid effects were measured by pupil diameter change (miosis).

RESULTS

Nelfinavir decreased intravenous and oral methadone plasma concentrations 40-50%. Systemic clearance, hepatic clearance, and hepatic extraction all increased 1.6- and 2-fold, respectively, for R- and S-methadone; apparent oral clearance increased 1.7- and 1.9-fold. Nelfinavir stereoselectively increased (S>R) methadone metabolism and metabolite formation clearance, and methadone renal clearance. Methadone bioavailability and P-glycoprotein activity were minimally affected. Nelfinavir decreased alfentanil systemic and apparent oral clearances 50 and 76%, respectively. Nelfinavir appeared to shift the methadone plasma concentration-effect (miosis) curve leftward and upward.

CONCLUSIONS

Nelfinavir induced methadone clearance by increasing renal clearance, and more so by stereoselectively increasing hepatic metabolism, extraction and clearance. Induction occurred despite 50% inhibition of hepatic CYP3A4/5 activity and more than 75% inhibition of first-pass CYP3A4/5 activity, suggesting little or no role for CYP3A in clinical methadone disposition. Nelfinavir may alter methadone pharmacodynamics, increasing clinical effects.

[Effect of distinct sociodemographic variables on progression of HIV infection in a cohort of drug users]

OBJECTIVE

To analyze whether the effectiveness of combined antiretroviral therapy in delaying progression to AIDS and death is affected by social inequities in a cohort of HIV-positive injecting drug users (IDUs).

METHODS

A cohort of 3,122 HIV-positive IDUs identified in the AIDS Information and Prevention Centers of the autonomous region of Valencia was analyzed, with further follow-up in 1,876. Progression to AIDS and death after seroconversion were calculated by Kaplan-Meier estimation according to sociodemographic variables (age, sex, education, marital status, length of addiction). Cox regression models were also fitted.

RESULTS

No significant differences were observed according to the variables considered when analyzing time to AIDS development. Evaluation of survival time revealed that individuals with further follow-up showed an excess of mortality (HR = 1.35; 95%CI: 0.20-1.54). For individuals without follow-up, mortality risk was reduced in those with secondary school education (HR = 0.51; 95%CI: 0.35-0.74) and with university education (HR = 0.41; 95%CI: 0.18-0.93) compared with those with no education. When individuals with follow-up were analyzed, the differences lost significance for those with secondary school education (HR = 0.92; 95%CI: 0.72-1.19) and university education (HR = 0.62; 95%CI: 0.35-1.11).

CONCLUSIONS

The mortality excess found in IDUs with lower educational levels, especially among those not seeking healthcare in the initial period after being identified as HIV-positive, highlights the need for interventions aimed at facilitating access to health systems, especially among the socially disadvantaged.

Infrequent illicit methadone use among stimulant-using patients in methadone maintenance treatment programs: a national drug abuse treatment clinical trials network study

We sought to determine the prevalence, patterns, and correlates of past-month illicit methadone use and history of regular illicit use among stimulant-using methadone maintenance treatment patients. We obtained self-reported information on illicit methadone use from 383 participants recruited from six community-based methadone maintenance programs. Overall, 1.6% of participants reported illicit use in the past month, and 4.7% reported a history of regular use. Younger age and history of outpatient psychological treatment were associated with increased odds of past-month illicit use. Illicit methadone use among patients in maintenance programs is infrequent; however, a number of factors may increase risk of illicit use.