Continued heroin use during methadone treatment: relationships between frequency of use and reasons reported for heroin use

Impact of a methadone maintenance therapy pilot in Vietnam and its role in a scaled-up response

BACKGROUND

As a dual response to the HIV epidemic and the high level of injecting drug use in Vietnam, the Ministry of Health (MOH) initiated a pilot methadone maintenance therapy (MMT) program in Hai Phong and Ho Chi Minh City (HCMC) in early 2009. The objectives of the pilot were to provide evidence on whether MMT could be successfully implemented in Vietnam and scaled up to other localities.

METHODS

A prospective study was conducted among 965 opiate drug users admitted to the pilot. Data on demographic characteristics, sexual behaviors, substance use behaviors (including heroin use), and blood-borne virus infection (HIV, hepatitis B, and hepatitis C) were collected at treatment initiation and then again at 3-, 6-, 9-, 12-, 18-, and 24-month intervals thereafter.

RESULTS

Twenty-four months after treatment initiation, heroin use as measured by urine test or self-report had reduced from 100 % of participants at both sites to 14.6 % in Hai Phong and 22.9 % in HCMC. When adjusted for multiple factors in Generalized Estimating Equations (GEE) logistic regression modeling, independent predictors of continued heroin use after 24 months of MMT in HCMC were the following: poor methadone adherence (adjusted odds ratio (AOR) = 3.7, 95 % confidence interval (CI) 1.8-7.8); currently on antiretroviral treatment (ART) (AOR = 1.8, 95 % CI 1.4-2.4); currently on TB treatment (AOR = 2.2, 95 % CI 1.4-3.4); currently experiencing family conflict (AOR = 1.6, 95 % CI 1.1-2.4); and currently employed (AOR = 0.8, 95 % CI 0.6-1.0). For Hai Phong participants, predictors were the following: currently on ART (AOR = 2.0, 95 % CI = 1.4-3.0); currently experiencing family conflict (AOR = 2.0, 95 % CI = 1.0-3.9); and moderate adherence to methadone (AOR = 2.1, 95 % CI = 1.2-1.9). In Hai Phong, the percentage of participants who were employed had also increased by end of study from 35.0 to 52.8 %, while in HCMC the level remained relatively unchanged, between 52.2 and 55.1 %.

DISCUSSION

Study findings were used in multiple fora to convince policymakers and the public on the significant and vital role MMT can play in reducing heroin use and improving quality of life for individuals and families. Four years after this study was completed, Vietnam had expanded MMT to 162 clinics in 44 provinces serving 32,000 patients.

Characterizing opioid withdrawal during double-blind buprenorphine detoxification

BACKGROUND

Prescription opioid (PO) abuse has become an urgent public health issue in the United States. Detoxification is one important treatment option, yet relatively little is known about the time course and severity of opioid withdrawal during buprenorphine detoxification.

METHODS

This is a secondary analysis of data from a randomized, placebo-controlled, double-blind evaluation of 1, 2, and 4-week outpatient buprenorphine tapers among primary prescription opioid (PO) abusers. The aim is to characterize the time course and severity of buprenorphine withdrawal under rigorous, double-blind conditions, across multiple taper durations, and using multiple withdrawal-related measures (i.e., self-report and observer ratings, pupil diameter, ancillary medication utilization). Participants were PO-dependent adults undergoing buprenorphine detoxification and biochemically-verified to be continuously abstinent from opioids during their taper (N = 28).

RESULTS

Participants randomly assigned to the 4-week taper regimen experienced a relatively mild and stable course of withdrawal, with few peaks in severity. In contrast, the 1- and 2-week taper groups experienced stark increases in withdrawal severity during the week following the last buprenorphine dose, followed by declines in withdrawal severity thereafter. The 4-week taper group also reported significantly fewer disruptions in sleep compared to the other experimental groups. When predictors of withdrawal were examined, baseline ratings of "Expected Withdrawal Severity" was the most robust predictor of withdrawal experienced during the taper.

CONCLUSION

Data from this trial may inform clinicians about the expected time course, magnitude, and pattern of buprenorphine withdrawal and aid efforts to identify patients who may need additional clinical support during outpatient buprenorphine detoxification.

Predictors of non-use of illicit heroin in opioid injection maintenance treatment of long-term heroin dependence

AIMS

To investigate baseline and concurrent predictors of non-use of illicit heroin among participants randomized to injectable opioids in the North American Opiate Medication Initiative (NAOMI) clinical trial.

METHODS

NAOMI was an open-label randomized controlled trial comparing the effectiveness of injectable diacetylmorphine and hydromorphone for long-term opioid-dependency. Outcomes were assessed at baseline and during treatment (3, 6, 9, 12months). Days of non-use of illicit heroin in the prior month at each follow-up visit were divided into three categories: Non-use; Low use (1 to 7days) and High use (8days or more). Tested covariates were: Sociodemographics, Health, Treatment, Drug use and illegal activities. Mixed-effect proportional odds models with random intercept for longitudinal ordinal outcomes were used to assess the predictors of the non-use of illicit heroin.

RESULTS

139 participants were included in the present analysis. At each follow-up visit, those with non-use of illicit heroin represented 47.5% to 54.0% of the sample. Fewer days of cocaine use (p=0.074), fewer days engaged in illegal activities at baseline (p<0.01) and at each visit (p<0.01), less money spent on drugs (p<0.001), days with injection opioid or oral methadone treatment (p<0.001) and total mg of injectable opioids taken (p<0.001), independently predicted lower use of illicit heroin.

CONCLUSIONS

The independent effect of several concurrent factors besides the injection of opioid dose suggests benefits from the clinic that go beyond the provision of the medication alone. Thus, this supervised model of care presents an opportunity to maximize the beneficial impact of medical and psychosocial components of the treatment on improving outcomes associated with non-use of illicit heroin.

Patterns of abstinence or continued drug use among methadone maintenance patients and their relation to treatment retention

The efficacy and effectiveness of methadone maintenance treatment (MMT) in the medical management of opioid addiction has been well-established, but treatment outcomes are compromised by the continued use of licit and illicit drugs during MMT. The present study examined the relationship between in-treatment illicit drug use and retention and dropout of 604 MMT patients in Washington, D.C. Sixty-eight percent of patients did not test positive for an unprescribed drug during the study period. Of patients who tested positive for an illicit drug during the baseline period, 55% tested positive for cocaine, 44% for opiates, 23% for THC, 20% for benzodiazepines, 7% for PCP, and 4% for amphetamines. Those testing positive were three times more likely to leave treatment than those who did not test positive. Testing positive for one drug doubled the rate of attrition; testing positive for multiple drugs quadrupled the risk of attrition. Non-prescribed opioid or benzodiazepine use was a predictor of MMT dropout, but prescribed opioid or benzodiazepine use was not. Continued illicit drug use poses significant risk for subsequent premature termination of MMT. Assertive clinical management of continued illicit drug use could provide mechanisms to enhance MMT retention and long-term recovery outcomes.

Predictors of non-prescribed opioid use after one year of methadone treatment: an attributable-risk approach (ANRS-Methaville trial)

BACKGROUND

The effectiveness of methadone as an opioid maintenance treatment (OMT) for opioid dependence has been widely demonstrated. However many patients continue to use other opioids while on methadone treatment. Studies assessing avoidable cases of continued non-prescribed opioid use during methadone treatment are sparse.

METHODS

At 12 months of treatment (M12), 158 subjects had available data on opioid use, measured using the Opiate Treatment Index. We identified variables associated with non-prescribed opioid use at M12, using a univariate logistic regression and two multivariate models, one incorporating only pre-treatment variables, the second adding the in-treatment variables. We also calculated attributable fractions for risk factors.

RESULTS

At M12, 32.3% of the patients had used non-prescribed opioids during the previous month. A good patient-physician relationship was the most influential factor associated with not using non-prescribed opioids after one year. Living with a heroin user after one year of treatment, using cocaine during treatment and hazardous alcohol consumption at enrolment were all associated with an increased risk of non-prescribed opioid use at M12. Analysis of attributable fractions indicated that living with a heroin user at M12 accounted for 21% of patients reporting non-prescribed opioid use at M12, while the lack of a good relationship with the physician accounted for 26%.

CONCLUSIONS

The attributable risk approach suggests that continued non-prescribed opioid use by a considerable proportion of individuals could potentially be reduced by improving patient-physician relationships, enhancing care for co-dependent patients and encouraging patients to modify their social network.

Persistence of heroin use despite methadone treatment: poor coping self-efficacy predicts continued heroin use

AIM

To evaluate the association between coping self-efficacy and persistent use of heroin by patients enrolled in a methadone treatment program.

DESIGN AND METHODS

Cross-sectional survey. One hundred and ninety-one patients attending outpatient methadone clinics in South-East England, United Kingdom. Validated questionnaires were used to assess drug use (Maudsley Addiction Profile), alcohol use (Alcohol Use Disorders Identification Test), mental health (Hospital Anxiety and Depression Scale) and coping self-efficacy (brief 8-item Drug Taking Confidence Questionnaire).

RESULTS

Half of the participants (95/191) reported heroin use in the preceding 14-day period. Heroin use during methadone treatment was associated with financial problems (P = 0.008), spending time with other drug users (P < 0.001), cocaine use (P = 0.002), low mood (P = 0.002) and dissatisfaction with the daily methadone dose (P = 0.014). Compared with 'Heroin-abstinent' patients, the 'Heroin' group reported significantly lower mean coping self-efficacy scores (t = 9.8, d.f. = 182, P < 0.001, effect size 1.17). After correcting for the effects of co-variants in a logistic regression model, the main determinants of persistent heroin use were 'coping self-efficacy' [B -0.05; standard error (SE) 0.008; Wald 36.6; odds ratio (OR) 0.95, 95% confidence interval (CI) 0.94, 0.97; P < 0.001] and 'dissatisfaction with methadone dose' (B 0.93; SE 0.46; Wald 4.1; OR 2.5, 95% CI 1.03, 6.25; P = 0.042). Satisfaction with methadone dose showed no association with self-efficacy. DISCUSSION AND CONCLUSIONS; While heroin use during methadone treatment can partly be explained by inadequate dosing, our data suggest a more complex picture with significant contribution from poor coping self-efficacy. Efforts aimed at enhancing and maintaining the patients' self-efficacy and social skills are likely to improve heroin and other drug use outcomes with added benefits for treatment completion rates and the throughput of methadone programs.

The North American Opiate Medication Initiative (NAOMI): profile of participants in North America's first trial of heroin-assisted treatment

The North American Opiate Medication Initiative (NAOMI) is a randomized controlled trial evaluating the feasibility and effectiveness of heroin-assisted treatment (HAT) in the Canadian context. Our objective is to analyze the profile of the NAOMI participant cohort in the context of illicit opioid use in Canada and to evaluate its comparability with patient profiles of European HAT studies. Recruitment began in February 2005 and ended in March 2007. Inclusion criteria included opioid dependence, 5 or more years of opioid use, regular opioid injection, and at least two previous opiate addiction treatment attempts. Standardized assessment instruments such as the European Addiction Severity Index and the Maudsley Addiction Profile were employed. A total of 251 individuals were randomized from Vancouver, BC (192, 76.5%), and Montreal, Quebec (59, 23.5%); 38.5% were female, the mean age was 39.7 years (SD:8.6), and participants had injected drugs for 16.5 years (SD:9.9), on average. In the prior month, heroin was used a mean of 26.5 days (SD:7.4) and cocaine 16 days (SD;12.6). Vancouver had significantly more patients residing in unstable housing (88.5 vs. 22%; p < 0.001) and higher use of smoked crack cocaine (16.9 days vs. 2.3 days in the prior month; p < 0.001), while a significantly higher proportion of Montreal participants reported needle sharing in the prior 6 months (25% vs. 3.7%; p < 0.001). In many respects, the patient cohort was similar to the European trials; however, NAOMI had a higher proportion of female participants and participants residing in unstable housing. This study suggests that the NAOMI study successfully recruited participants with a profile indicated for HAT. It also raises concern about the high levels of crack cocaine use and social marginalization.

Self administration of cocaine in monkeys receiving LAAM acutely or chronically

Polydrug abuse remains a common problem among opioid abusers as well as patients in opioid maintenance programs. Although cocaine abuse has been reported in patients receiving methadone, the incidence of cocaine use in patients receiving l-alpha-acetylmethadol (LAAM) has not been well established. The goal of this study was to determine whether acute or chronic administration of LAAM modified the reinforcing effects of cocaine using a self-administration procedure in rhesus monkeys. Four monkeys responded under a fixed ratio (FR) 30 schedule to receive i.v. infusions of cocaine (0.0032-0.32 mg/kg/infusion) in the absence of other treatment, after acute LAAM administration (0.1-1.0 mg/kg, s.c.), and during daily administration of 1.0 mg/kg of LAAM. Cocaine maintained self-administration responding that exceeded responding maintained by saline; acutely administered LAAM had small and variable effects on self administration of cocaine. Daily LAAM administration increased the number of infusions received of at least one dose of cocaine. These studies indicated that LAAM administration did not attenuate the reinforcing effects of cocaine, suggesting that LAAM would not likely alter cocaine abuse in patients undergoing treatment for opioid abuse.

Dextroamphetamine for cocaine-dependence treatment: a double-blind randomized clinical trial

A properly implemented agonist treatment regimen should improve retention and reduce illicit drug use. Cocaine-dependent subjects (N = 128) were enrolled in a 12-week randomized, double-blind, placebo-controlled trial. In the multistage dosing design, subjects initially received placebo (PBO) or 15 to 30 mg of dextroamphetamine sulfate, sustained-release capsules. At week 5, the dose doubled to 30 mg or 60 mg for active groups. Subjects attended the clinic twice a week, provided urine samples, obtained medication, and had one behavioral therapy session a week. Retention was best for the 15- to 30-mg group, whereas the proportion of benzoylecgonine-positive urine screens was, from lowest to highest, 30 to 60 mg, 15 to 30 mg, and PBO at study end. Dosing must be refined. The results provide support for additional examination of the agonist model in psychostimulant-dependence treatment.

Different forms of heroin and their relationship to cook-up techniques: data on, and explanation of, use of lemon juice and other acids

Recent reports of the use of lemon juice in the preparation of heroin for injection have failed to recognize the importance of the different forms of heroin (in the form of the salt or the base) and the impact of this on the chemical manipulation required before injection. One hundred and four opiate addicts in London were interviewed about the forms of heroin (white, brown, etc) and their relationship to cook-up techniques (use of heat and acid). White heroin was typically prepared with water and heat; brown heroin was prepared with acid (citric acid or Vitamin C (ascorbic acid) or lemon juice) and heat; pharmaceutical heroin was prepared with water only (i.e. neither acid nor heat). On the last occasion of heroin use, brown heroin had been the form most commonly used, with over 90% of the sample using citric acid or vitamin C. Lemon juice was rarely used, and heat was almost universally applied in conjunction with lemon juice.

Heroin-induced suppression of saccharin intake in water-deprived and water-replete rats

Rats suppress intake of a saccharin conditioned stimulus (CS) when paired with an aversive unconditioned stimulus such as lithium chloride. This phenomenon is referred to as a conditioned taste aversion (CTA). Rats also suppress intake of a saccharin CS when paired with a rewarding sucrose solution and when paired with a drug of abuse. Although the suppressive effects of drugs of abuse have long been interpreted as CTAs, evidence suggests that rats may suppress intake of the saccharin CS following taste-drug pairings because they are anticipating the rewarding rather than the aversive properties of the drug. Oddly, however, while all other drugs of abuse tested suppress intake of a gustatory CS, the highly reinforcing drug, heroin, is reportedly ineffective. The present study reexamined this issue in both water-deprived and water-replete rats using procedures that sustain both morphine- and cocaine-induced suppression of CS intake. The results showed that heroin greatly reduced CS intake following saccharin-heroin pairings and that this effect was less variable when assessed in water-replete subjects. When taken with other reports, these data suggest that rats suppress intake of a saccharin CS in anticipation of the availability of all drugs of abuse tested.

Cost of drug use and criminal involvement before and during methadone treatment

AIMS

To examine criminal behaviour in methadone clients as a function of expenditure on illicit drugs. To quantify the benefit of treatment for this group and to identify individuals who do not reduce criminal behaviour or substance use as a consequence of treatment.

DESIGN

Cross-sectional examination of key methadone-treatment variables (age, methadone dose and length of time in treatment), and self-reported levels of spending on illicit drugs before and during methadone treatment.

SETTING

All interviews were conducted in the community-based treatment centre of the Maudsley's addiction treatment services in South London.

PARTICIPANTS

One hundred consecutive opiate-dependent attenders at a community treatment clinic.

MEASUREMENTS

Data were collected using a self-report questionnaire and treatment characteristic data were collected from clinical case notes.

FINDINGS

There was a major overall reduction in spending on illicit drugs from before treatment to during treatment, consistent with previous findings; however, 15% of the sample either showed no change or actually increased their spending after entry to treatment. This group did not differ in terms of key treatment characteristics (age, methadone dose and length of time in treatment) and there was no significant correlation between levels of spending before and during treatment.

CONCLUSIONS

Despite substantial overall benefit, there is a subgroup of individuals for whom long-term treatment, even on high range doses of methadone, has no beneficial effect on criminal activity or drug use. Further research is required to establish the dynamics of this indirect treatment-benefit, and to explore the apparent resistance to treatment of the criminal behaviour of a small sub-group.