Census of Patients Receiving Methadone Treatment in a General Practice

Physicians' attitudes towards office-based delivery of methadone maintenance therapy: results from a cross-sectional survey of Nova Scotia primary-care physicians

Background

Approximately 90,000 Canadians use opioids each year, many of whom experience health and social problems that affect the individual user, families, communities and the health care system. For those who wish to reduce or stop their opioid use, methadone maintenance therapy (MMT) is effective and supporting evidence is well-documented. However, access and availability to MMT is often inconsistent, with greater inequity outside of urban settings. Involving community based primary-care physicians in the delivery of MMT could serve to expand capacity and accessibility of MMT programs. Little is known, however, about the extent to which MMT, particularly office-based delivery, is acceptable to physicians. The aim of this study is to survey physicians about their attitudes towards MMT, particularly office-based delivery, and the perceived barriers and facilitators to MMT delivery.

Methods

In May 2008, facilitated by the College of Physicians and Surgeons of Nova Scotia, a cross-sectional, e-mail survey of 950 primary-care physicians practicing in Nova Scotia, Canada was administered via the OPINIO on-line survey software, to assess the acceptability of office-based MMT. Logistic regressions, adjusted for physician sociodemographic characteristics, were used to examine the association between physicians’ willingness to participate in office-based MMT, and a series of measures capturing physician attitudes and knowledge about treatment approaches, opioid use, and methadone, as well as perceived barriers to MMT.

Results

Overall, 19.8% of primary-care physicians responded to the survey, with 56% who indicated that they would be willing to be involved in MMT under current or similar circumstances; however, willingness was associated with numerous attitudinal and systemic factors. The barriers to involvement in MMT that were frequently cited included a lack of training or experience in MMT, lack of support services, and potential challenges of working with an MMT patient population.

Conclusions

Study findings provide valuable information to help facilitate greater involvement of primary-care physicians in MMT, while highlighting concerns around administration, support, and training. Even limited uptake by primary-care physicians would greatly enhance MMT access in Nova Scotia, particularly for methadone clients located in rural communities. These findings are applicable broadly, to any jurisdictions where office-based MMT is not currently available.

Just call it "treatment"

Although many in the addiction treatment field use the term "medication-assisted treatment" to describe a combination of pharmacotherapy and counseling to address substance dependence, research has demonstrated that opioid agonist treatment alone is effective in patients with opioid dependence, regardless of whether they receive counseling. The time has come to call pharmacotherapy for such patients just "treatment". An explicit acknowledgment that medication is an essential first-line component in the successful management of opioid dependence.

Harm reduction, hepatitis C and opioid pharmacotherapy: an opportunity for integrated hepatitis C virus-specific harm reduction

While harm reduction advocates, policy makers and practitioners have a right to be proud of the impact of interventions such as needle and syringe programmes on HIV risk, we can be less sanguine about the ongoing high levels of HCV transmission among injecting drug users (IDUs) and the expanding burden of hepatitis C virus (HCV)-related liver disease. In this Harm Reduction Digest Drs Byrne and Hallinan from the Redfern Clinic and Dr Dore from the National Centre in HIV Epidemiology and Clinical Research offer a model of integrated HCV prevention and treatment services within the setting of opioid pharmacotherapy. In their experience, this common-sense approach provides an opportunity to reduce the burden of HCV and improve overall patient management. They believe that the key elements of a HCV-specific harm reduction model include: regular HCV testing; clinical assessment and determination of need for HCV treatment referral; use of broader HCV treatment inclusion criteria; and flexibility in opioid pharmacotherapy dosing. In an environment when our macro harm reduction interventions seem to have, at best, modest impact on HCV transmission, good clinical practice may be our most effective strategy against the HCV epidemic. This paper provides some practical suggestions as to how this can be done.

Hepatitis C virus incidence among injecting drug users on opioid replacement therapy

OBJECTIVE

To determine hepatitis C virus (HCV) incidence among injecting drug users (IDUs) receiving opioid replacement therapy (ORT).

METHODS

A retrospective cohort study was established in a primary care drug dependency treatment clinic. The cohort included all IDUs who commenced ORT after January 1996 with an initial anti-HCV antibody negative result and repeat testing prior to July 2003. HCV incidence was estimated for all subjects, with further comparison among those with continuous versus interrupted ORT.

RESULTS

Fifty-four subjects were initially HCV antibody negative and had repeat testing. Five cases of HCV antibody seroconversion occurred during a total follow-up period of 131.1 person years (py), an incidence of 3.8/100 py (95% CI 1.2-8.9/ 100 py). Four seroconversions occurred in the subgroup with interrupted ORT (n=20), an incidence of 7.4/100 py (95% CI 2.0-18.9/100 py), compared with one seroconversion in the subgroup with continuous ORT (n=34), an incidence of 1.3/100 py (95% CI 0.03-7.3/100 py).

CONCLUSIONS

HCV incidence among IDUs receiving ORT in our clinic was relatively low. Those IDUs without interruptions to their treatment appeared to be at particularly low risk of HCV infection. These findings support the role of ORT in HCV prevention for IDUs.

Referral for chronic hepatitis C treatment from a drug dependency treatment setting

To examine rates and predictors of referral for hepatitis C virus (HCV) treatment and preliminary treatment outcomes in injecting drug users (IDUs) receiving opioid replacement treatment, a prospective clinical audit was undertaken in an inner city Sydney drug dependency treatment practice between December 2002 and November 2005. The majority of IDUs (178/237; 75%) were HCV antibody positive, of whom 170 were HCV treatment naïve with no absolute treatment contraindications. Among these 170 patients, 121 (71%) had chronic HCV. Based on risk factors for HCV disease progression, 63 of 121 (52%) chronic HCV patients were targeted for referral; these patients were older, had higher alanine aminotransferase levels and longer estimated duration of HCV infection. Of these 63 patients, 43 were referred to a hepatitis treatment clinic, and 27 attended during the audit period. Patients who attended for treatment assessment were more likely to have genotype 2 or 3 (p<0.001), but socio-behavioural factors were similar. Liver biopsy was performed in 20 patients, with moderate or greater fibrosis in 18 patients. Of 14 patients commenced on pegylated interferon-alpha and ribavirin therapy, one ceased treatment due to non-response, 10 have completed treatment, all with an end-of-treatment (n=4) or sustained virological response (n=6), and treatment is ongoing in three. The development of HCV treatment referral criteria has allowed prioritisation of patients for referral, potentially halving those that require early assessment. Preliminary HCV treatment outcomes are encouraging and highlight the potential for reducing liver disease burden in this patient population.

A 5-year evaluation of a methadone medical maintenance program

Methadone medical maintenance (MMM) is a model for the treatment of opioid dependence in which a monthly supply of methadone is distributed in an office setting, in contrast to more highly regulated settings where daily observed dosing is the norm. We assessed patient characteristics and treatment outcomes of an MMM program initiated in the Bronx, New York, in 1999 by conducting a retrospective chart review. Participant characteristics were compared with those of patients enrolled in affiliated conventional methadone maintenance treatment programs. Patients had diverse ethnicities, occupations, educational backgrounds, and income levels. Urine toxicology testing detected illicit opiate and cocaine use in 0.8% and 0.4% of aggregate samples, respectively. The retention rate was 98%, which compares favorably with the four other MMM programs that have been reported in the medical literature. This study demonstrates that selected patients from a socioeconomically disadvantaged population remained clinically stable and engaged in treatment in a far less intensive setting than traditional methadone maintenance.

Therapeutic thresholds in methadone maintenance treatment: a receiver operating characteristic analysis

Twenty-four-hour trough (R)- and (R,S)-methadone plasma concentrations were measured on 94 methadone maintenance treatment (MMT) patients classified as 'responders' or 'non-responders', based on urine toxicology evidence of recent illicit opiate use. Receiver operating characteristic (ROC) curves for daily dose, dose/bodyweight, and (R)- and (R,S)-methadone trough plasma concentrations were used to identify optimal thresholds; areas under the curve (AUC) were used to compare predictive power. Non-responders (n=37) had a lower mean dose (73 mg/day versus 147 mg/day; p<0.001), (R)-methadone concentration (136 ng/ml versus 223 ng/ml; p<0.005) and (R,S)-methadone concentration (266 ng/ml versus 409 ng/ml; p=0.001) than responders. On multivariate regression, duration of treatment and methadone dose were significantly associated with treatment response. After backward stepwise regression, each year of treatment increased the odds of abstinence from illicit opioid use by 34% (OR 1.34; 95% CI 1.14-1.57)); each 20mg of methadone dose by 36% (OR 1.36 CI; 95% CI 1.11-1.67). On ROC analysis, AUC for daily dose (0.77, 95% CI 0.68-0.87), dose/bodyweight (0.76, 95% CI 0.66-0.85), (R)-methadone (0.73, 95% CI 0.63-0.84) and (R,S)-methadone concentration (0.70, 95% CI 0.59-0.81) did not differ significantly. Dose/bodyweight, and trough plasma concentrations of (R)- or (R,S)-methadone were no better predictors of treatment response than daily dose, and did not improve the fit of the model for treatment outcome as judged by the likelihood ratio test (p=0.21, 0.88, and 0.97, respectively). Optimal therapeutic thresholds (sensitivity, specificity) were: daily dose 100mg/day (67%, 81%); (R)-methadone 200 ng/ml (51%, 78%); (R,S)-methadone 400 ng/ml (40%, 81%). Thresholds with specificity near 90% (dose 140 mg/day; (R)-methadone 250 ng/ml; (R,S)-methadone 500 ng/ml) may help guide dose titration for patients continuing to use illicit opiates.

Patterns of drug use among a sample of drug users and injecting drug users attending a General Practice in Iran

AIM

This study aimed to examine drug use, drug treatment history and risk behaviour among a sample of Iranian drug users seeking treatment through a general practice clinic in Iran.

METHODS

Review of medical records and an intake questionnaire at a large general practice in Marvdasht, Iran, with a special interest in drug dependence treatment. Records from a random sample of injecting drug users (IDU), non-injecting drug users (DU) and non-drug using patients were examined.

RESULTS

292 records were reviewed (34% IDU, 31% DU and 35% non-drug users). Eighty-three percent were males; all females were non-drug users. The mean age of the sample was 30 years. Of the IDU sample, 67% reported sharing a needle or syringe, 19% of these had done so in prison. Of those who had ever used drugs, being 'tired' of drug use was the most common reason for seeking help (34%). Mean age of first drug use was 20 years. The first drugs most commonly used were opium (72%), heroin (13%) and hashish/ other cannabinoids (13%). Three quarters reported having previously attempted to cease their drug use. IDU were more likely than DU to report having ever been imprisoned (41% vs 7%) and 41% to have used drugs in prison.

CONCLUSION

This study has shown that there is a need for general practice clinics in Iran to treat drug users including those who inject and that a substantial proportion of those who inject have shared needles and syringes, placing them at risk of BBVI such as HIV and hepatitis C. The expansion of services for drug users in Iran such as needle and syringe programs and pharmacotherapies are likely to be effective in reducing the harms associated with opium use and heroin injection.

Methadone treatment for opiate dependent patients in general practice and specialist clinic settings: Outcomes at 2-year follow-up

Few studies have investigated methadone treatment of opiate dependent patients in primary health care settings. Using a prospective cohort design, the study investigated outcomes at 1 and 2 years for 240 patients treated by general practitioners (n = 79) or drug clinics (n = 161) at sites across England. Mean daily methadone dose for both groups was 50 mg. Reductions in illicit drug use, injecting, sharing injecting equipment, psychological and physical health problems, and crime, were found in both groups at follow-up. Patients treated in general practitioner (GP) settings reported less frequent benzodiazepine and stimulant use, and fewer psychological health problems at follow-up. Alcohol use outcomes were poor for both groups. Differences in treatment practices were found for GPs and clinics. Results show substantial reductions in a range of problems behaviours, among unselected samples of opiate dependent patients treated in GP and in clinic settings, which are sustained to 1-year and 2-year follow-up.

Counseling as an intervention for the cocaine-abusing methadone maintenance patient

Using archival data from Bay Area Addiction Research and Treatment (BAART), a methadone treatment provider, this study examined the efficacy of the clinical intervention of counseling on cocaine use by BAART patients. California State Assembly Bill 2071 mandated that patients at methadone clinics be required to undergo a minimum of 50 minutes of counseling per month. Records of 179 patients continuously active in treatment beginning 12 months prior to (i.e., the baseline) and two years after AB 2071's implementation were reviewed. These patients were also identified as cocaine abusers. A pretest-intervention-posttest design was employed, with the increased counseling mandated by AB 2071 as the intervention. Cocaine abusers' urinalysis results during the one-year baseline were compared to the time period following AB 2071's implementation. The independent variable was the amount of counseling received and the dependent variable was cocaine use. The prediction was that cocaine-abusing methadone maintenance patients would have fewer cocaine positive urine analyses following AB 2071's implementation than in the 12-month baseline period preceding AB 2071. Results supported the main hypothesis that cocaine-abusing patients would show better improvement following AB 2071. Additionally, the actual amount of time in counseling was shown to lead to greater improvement in treatment for cocaine abusers. An important secondary finding was that heroin use was also negatively correlated to time in counseling. There were no gender differences in the response to the counseling treatment.

Access to narcotic addiction treatment and medical care: prospects for the expansion of methadone maintenance treatment

Methadone maintenance treatment (MMT) for opioid addiction is safe and effective but underutilized because of inaccessibility, under-financing and the stigma generally attached to maintenance therapies. In addition, cumbersome regulation of methadone prescription and treatment impedes the delivery of care and retards expansion of methadone maintenance into office practice settings. Exaggeration of the problem of methadone diversion further hinders development of MMT. Despite obstacles, methadone maintenance has been successfully expanded and extended into primary care settings abroad. Initial trials in the U.S. have shown that methadone maintenance in physician office-based settings yields positive results with some advantages over care in large methadone clinics. Alternatives to methadone, such as buprenorphine, are also being explored in primary care settings. With implementation of the NIH Consensus Statement on Effective Medical Treatment of Heroin Addiction, including training of primary care physicians, methadone maintenance treatment could reach many more patients, achieve higher success rates, and substantially reduce the deleterious effects of opioid addiction in the U.S.