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. Author manuscript; available in PMC: 2017 Jul 1.
Published in final edited form as: Subst Abus. 2016 Jan 5;37(3):387–391. doi: 10.1080/08897077.2015.1135225

Characteristics of methadone maintenance treatment patients prescribed opioid analgesics

Matthew C Glenn 1, Nancy L Sohler 3, Joanna L Starrels 1,2, Jeronimo Maradiaga 1, John J Jost 1, Julia H Arnsten 1,2, Chinazo O Cunningham 1,2
PMCID: PMC4935628  NIHMSID: NIHMS795083  PMID: 26731299

Abstract

Background

Opioid analgesic use and disorders have dramatically increased among the general American population and those receiving methadone maintenance treatment (MMT). Most research among MMT patients focuses on opioid analgesics misuse or disorders; few studies focus on MMT patients prescribed opioid analgesics. We describe demographic, clinical, and substance use characteristics of MMT patients prescribed opioid analgesics and compare them to MMT patients not prescribed opioid analgesics.

Methods

We conducted a cross-sectional secondary data analysis using screening interviews from a parent study. From 2012–2015, we recruited adults from 3 MMT Bronx clinics. Questionnaire data included: patterns of opioid analgesic use, substance use, comorbid illnesses, and demographic characteristics. Our main dependent variable was patients’ report of currently taking prescribed opioid analgesics. To compare characteristics between MMT patients prescribed and not prescribed opioid analgesics, we conducted chi-squared tests, t-tests, and Mann-Whitney U tests.

Results

Of 611 MMT patients, most reported chronic pain (62.0%), HCV infection (52.1%), and currently using illicit substances (64.2%). Of the 29.8% who reported currently taking prescribed opioid analgesics, most misused their opioid analgesics (57.5%). Patients prescribed (versus not prescribed) opioid analgesics were more likely to report HIV infection (aOR=1.6, 95% CI: 1.1–2.3) and chronic pain (aOR=7.6, 95% CI: 4.6–12.6).

Conclusion

Among MMT patients primarily in three Bronx clinics, nearly one-third reported taking prescribed opioid analgesics. Compared to patients not prescribed opioid analgesics, those prescribed opioid analgesics were more likely to report chronic pain and HIV infection. However, between these patients, there was no difference in illicit substance use. These findings highlight the complexity of addressing chronic pain in MMT patients.

Introduction

Opioid analgesic use and disorders have dramatically increased over the past decade1. This is true for the general population and for those receiving methadone maintenance treatment (MMT). Among patients newly entering MMT programs, 67% and 82% used opioid analgesics within the previous month and year, respectively2,3, and up to 52% sought treatment primarily for opioid analgesics use disorders2–4. Most research examining opioid analgesic use in MMT patients focuses on opioid analgesics misuse or disorders.2–5 However, few studies have specifically focused on MMT patients who are prescribed opioid analgesics.

A contributing factor to opioid analgesic use among MMT patients may be the high prevalence and severity of pain. Up to 61% of MMT patients experience chronic pain6,7 and often the chronic pain is severe7,8. Indeed, MMT patients with chronic pain have higher rates of prescribed and illicit opioid analgesic use than those without chronic pain6. This may occur because MMT patients have a low tolerance for pain9–11, and they may request that providers prescribe opioid analgesics for their pain, or they may self-medicate with illicit opioid analgesics. However, providers may be weary of prescribing opioid analgesics to patients with opioid use disorders12–14. Because of the challenges in balancing the treatment of MMT patients’ opioid use disorder and chronic pain, wide variability exists in providers’ treatment strategies12. Further, minimal data exist to guide providers’ decisions about prescribing opioid analgesics15.

To better understand prescription opioid analgesic use among MMT patients, we sought to describe the demographic, clinical, and substance use characteristics of MMT patients prescribed opioid analgesics and compare them to MMT patients who were not prescribed opioid analgesics.

Methods

To compare characteristics of MMT patients prescribed versus not prescribed opioid analgesics, we conducted a cross-sectional secondary data analysis using screening interviews collected between June 2012 and June 2015 from a parent study. The study was registered in ClinicalTrials.gov (NCT01376570) and approved by the Albert Einstein College of Medicine Institutional Review Board. All participants provided oral informed consent.

Parent study

The ongoing parent study is a randomized trial to test the efficacy of an abstinence-based contingency management intervention on HIV outcomes16,17. The target population is HIV-infected active drug users (opioids or cocaine) who are receiving HIV treatment but who have suboptimal HIV outcomes. The intervention consists of providing escalating financial incentives that are contingent on abstinence (urine samples free of opiates, oxycodone, and cocaine). The control condition consists of providing performance feedback based on urine toxicology results. Participants have 44 research visits over a 7-month period, and data sources include urine samples, blood samples, pill counts, and medical record data.

Initially, the parent study’s recruitment efforts focused on targeting patients in three MMT clinics. These clinics, which are affiliated with an academic institution in the Bronx, make up the second largest substance abuse treatment program in New York, providing MMT to over 4200 opioid-dependent adults. Most MMT patients in these clinics are racial/ethnic minorities, male, and live under the federal poverty line. Recruitment efforts in these three clinics include: 1) study staff approaching patients in MMT clinic waiting rooms; 2) brochures and flyers posted in MMT clinics and surrounding communities; and 3) MMT clinic providers referring patients. Because of recruitment challenges, recruitment efforts were expanded to include: targeting patients at an affiliated HIV clinic, providing incentives for participants to refer their peers, and placing advertisements in a local newspaper.

Eligibility criteria for the parent study include: 1) at least 18 years of age; 2) fluency in English or Spanish; 3) HIV infection; 4) taking highly active antiretroviral therapy for at least 16 weeks; 5) less than 100% adherence to antiretroviral therapy; 6) most recent HIV viral load > 40 copies/mL; 7) (a) opioid-dependence and receiving opioid agonist treatment, or (b) cocaine abuse or dependence; 8) in the prior month, (a) self-reported cocaine or heroin use or (b) misuse of prescription opioid analgesics; and 9) at least one urine toxicology test positive for opiates, oxycodone or cocaine during the 4-week run-in period. Exclusion criteria for the parent study include: 1) inability to give informed consent; 2) inability to follow the research protocol; 3) current chronic pain syndrome that requires prescription opioid analgesics for at least one month; 4) three or more hospitalizations over the prior 6-month period; and 5) missing more than 4 of the 8 research visits during the 4-week run-in period.

Participants for the current analysis

For this analysis, we included participants who underwent screening interviews with the parent study and met the following criteria: 1) at least 18 years of age, 2) fluent in English or Spanish, 3) self-reported currently receiving MMT, and 4) provided complete data on prescribed opioid analgesic use and pain. Of the 1155 individuals screened by the parent study, 611 met these criteria and are included in this analysis.

Data collection and measures

Interviews were conducted face-to-face in a private room or via telephone, and responses were directly entered into a database by study staff. The 31-question interview was based on previously validated questionnaires and lasted approximately 10 minutes18–21. Questionnaire domains included: patterns of opioid analgesic use; substance use; substance abuse treatment; comorbid illnesses, including chronic pain; and demographic characteristics.

Outcome variable

We considered patients to be currently prescribed opioid analgesics if they gave an affirmative response to the following two questions: “In the past month have you taken any prescription painkillers that were either prescribed or not prescribed to you? (By painkillers, I mean percocet, oxycontin, codeine, vicodin, dilaudid, morphine and other similar medications)” and “Were any of those prescription painkillers prescribed to you?” Patients giving any other combination of responses were considered to be not currently prescribed opioid analgesics.

Other variables

To assess misuse of prescribed opioid analgesic, patients were asked, “In the past month, have you used more of your prescription painkiller, that is, taken a higher dosage, than is prescribed for you?” and “In the past month, have you used your prescription painkiller more often, that is, shorten the time between dosages, than is prescribed for you?”18. To determine illicit opioid analgesic use, patients who gave an affirmative response to the question “In the past month have you taken any prescription painkillers that were either prescribed or not prescribed to you?” were also asked “Were any of those prescription painkillers not prescribed to you?” Those answering affirmatively were considered to have illicit opioid analgesic use. To determine other illicit substance use, patients were asked about heroin, cocaine, and marijuana use within the previous 30 days19. Those who reported using a substance in the previous 30 days were considered current users of that substance. To assess alcohol use, patients were asked how often they had a drink containing alcohol20. Those who reported never having a drink containing alcohol were categorized as not using alcohol; all others were considered alcohol users. Patients were asked the number of cigarettes they smoked on a typical day. Those reporting zero cigarettes were considered to not use cigarettes; all others were considered cigarette users. Methadone maintenance treatment duration was determined by asking patients how long they have been in a MMT program. To determine comorbid illnesses, patients were asked if they had HIV infection, hepatitis C viral (HCV) infection, and diabetes. To determine chronic pain, patients were asked if they had a pain condition that caused pain on most days and lasted at least 3 months21. Sociodemographic characteristics included age, gender (male, female, transgender), and race/ethnicity (Hispanic, non-Hispanic black, non-Hispanic white, non-Hispanic other).

Data analysis

To compare characteristics between MMT patients prescribed opioid analgesics and those not prescribed opioid analgesics, we first conducted bivariate analyses with chi-squared tests for categorical variables and t-tests or Mann-Whitney U tests for continuous variables. To identify characteristics that were independently associated with prescribed opioid analgesic use, we then created a logistic regression model including characteristics that had p<0.20 on bivariate analyses (race/ethnicity, HIV infection and chronic pain). Analyses were conducted using STATA version 10.

Results

Of the 611 MMT patients, the mean age was 51.5 years, and most were Hispanic (61.5%) and male (61.5%; See Table 1). Most reported a chronic pain condition (62.0%), half reported HCV infection (52.1%), and many reported HIV infection (41.5%). Illicit substance use was common; 22.3% reported illicit opioid analgesic use, 36.8% heroin use, 34.9% cocaine use, and 29.6% marijuana use. Overall, 64.2% reported using at least one illicit substance. Prescribed opioid analgesic use was reported by 29.8%, and of these patients, most reported using their prescribed opioid analgesics in higher dosages or more frequently than prescribed (57.5%). In addition, of those prescribed opioid analgesics, illicit opioid analgesic (24.2%), heroin (33.5%), cocaine (35.9%), and marijuana (27.5%) use were common.

Table 1.

Characteristics of methadone maintenance treatment patients prescribed and not prescribed opioid analgesics

Characteristics Total
N (%)		 Prescribed opioid analgesics, N (%)
(N=611) Yes (N=182) No (N=429)
Demographic characteristics
Age (mean years ± SD) 51.5 + 8.6 51.9 ± 7.7 51.4 + 9.0
Male 376 (61.5) 111 (61.0) 265 (61.8)
Race/ethnicity
 Hispanic
 Non-Hispanic black
 Non-Hispanic white
 Non-Hispanic other
376 (61.5)
156 (25.5)
60 (9.8)
19 (3.1)
112 (61.5)
56 (30.8)
7 (3.9)*
7 (3.9)
264(61.5)
100 (23.3)
53 (12.4)
12 (2.8)
Clinical characteristics
HIV infection 253 (41.5) 93 (51.4)* 160 (37.3)
Hepatitis C virus infection 318 (52.1) 90 (49.7) 228 (53.2)
Diabetes 102 (16.7) 26 (14.3) 76 (17.7)
Chronic pain condition lasting at least 3 months 379 (62.0) 162 (89.0)** 217 (50.6)
Duration of methadone maintenance treatment (median months, IQR) 48.7 (12.2, 133.8) 60.8 (12.2, 133.8) 48.7 (12.2, 188.8)
Patterns of prescribed opioid analgesic use
Prescribed opioid analgesics taken in higher doses than prescribed – 86 (48.0) –
Prescribed opioid analgesics taken more frequently than prescribed – 81 (45.3) –
Prescribed opioid analgesics taken in higher doses or more frequently than prescribed – 103 (57.5) –
Current substance use
Cigarettes 529 (86.6) 157(86.3) 372 (86.7)
Alcohol 289 (47.5) 80 (44.4) 209 (48.8)
Illicit opioid analgesic 136 (22.3) 44 (24.2) 92 (21.5)
Heroin 225 (36.8) 61 (33.5) 164 (38.2)
Cocaine 213 (34.9) 65 (35.9) 148 (34.5)
Marijuana 181 (29.6) 50 (27.5) 131(30.5)
Any Illicit substancea 392 (64.2) 114 (62.6) 278 (64.8)
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Missing data: 3 for patterns of opioid analgesic use, 3 for alcohol use, 1 for cocaine use, 1 for HIV infection, 1 for hepatitis C viral infection

*

p<0.005

**

p<0.001

a

Use of illicit opioid analgesics, heroin, cocaine, or marijuana

Compared to MMT patients not prescribed opioid analgesics, those prescribed opioid analgesics were more likely to report HIV infection (37.3% vs. 51.4%, p<0.005) and chronic pain (50.6% vs. 89.0%, p<0.001) and less likely to be non-Hispanic white (12.4% vs. 3.9% p<0.005). In multivariate analysis, HIV infection (aOR=1.6, 95% CI: 1.1–2.3) and chronic pain (aOR=7.6, 95% CI: 4.6–12.6) remained significantly associated with prescribed opioid analgesic use.

Discussion

Among methadone maintenance treatment patients in primarily three Bronx clinics, nearly one-third reported they were currently prescribed opioid analgesics. Of these patients, the majority reported misusing their prescribed opioid analgesics. Similar to MMT patients not prescribed opioid analgesics, most who were prescribed opioid analgesics reported using illicit substances. Compared to those not prescribed opioid analgesics, patients prescribed opioid analgesics were more likely to report a chronic pain condition and HIV infection. Our findings highlight the complexity of addressing chronic pain in MMT patients, most of whom have ongoing illicit substance use while taking prescribed opioid analgesics.

To our knowledge, only two other studies have characterized prescribed opioid analgesic use among MMT patients22,23. Although both of these studies were conducted in Canada, where the delivery of MMT is vastly different than in the US, our findings are similar. In our study, 29.8% of MMT patients were prescribed opioid analgesics, which is similar to the 18% and 34% of MMT patients prescribed opioid analgesics in Ontario and British Columbia, respectively. In our study, the vast majority of MMT patients taking prescribed opioid analgesics reported chronic pain, and half had comorbid conditions that contribute to chronic pain, such as HIV and hepatitis C virus infection. Similar to our findings, Nosyk and colleagues also found that among MMT patients, prescription opioid analgesics use was associated with medical comorbitiy19. Because we did not ask patients about the provider prescribing opioid analgesics, we are unsure if opioid analgesics were prescribed by providers within or outside of the MMT programs. However, Canadian studies report that the majority of opioid analgesics prescribed to MMT patients were from non-MMT providers19,20. In the US, because MMT and medical treatment tend to be delivered in separate facilities by separate providers24, MMT providers are likely to be unaware of patients’ prescribed opioid analgesic use, and medical providers prescribing opioid analgesics are often unaware of MMT25. Given the challenges of simultaneously treating chronic pain and opioid use disorders, coordinated and integrated care are important strategies that can address these challenges and are recommended by national treatment guidelines26. Additionally, these strategies of coordinating or integrating treatment of medical and substance-related illnesses have been associated with improved outcomes in prior studies22–28. Coordination and integration of care can vary depending on settings, and can include shared treatment plans between providers, or management of both chronic pain and opioid use disorders by one provider.

Our study adds to the literature by describing high levels of prescribed opioid analgesic misuse along with high levels of illicit substance use among MMT patients prescribed opioid analgesics. In addition, the simultaneous use of prescribed opioid analgesics with other illicit substances, including heroin, illicit opioid analgesics, cocaine and marijuana, is concerning. The addition of prescribed opioid analgesics to methadone and other illicit opioids may place patients at increased harm due to the risk of overdose29,30. Being prescribed opioids did not appear to protect patients from, nor increase risk of using heroin or illicit opioid analgesics. Taken together, our findings highlight the challenges providers face when treating opioid dependence, especially among patients with a high prevalence of chronic pain and other comorbid illnesses.

This study has limitations. Our sample was a convenience sample of patients predominantly receiving treatment from three Bronx MMT clinics, and because it was part of a larger study, we particularly targeted HIV-infected patients. Therefore, we cannot determine prevalence of prescribed opioid analgesic use or illicit substance use, and our findings may not be generalizeable to other settings or geographic regions. All data were self- reported and were not verified by medical records or biological specimens. Finally, for this analysis, because we used a cross-sectional study design and a brief questionnaire, we cannot determine causality between prescribed opioid analgesic use and illicit substance use. We are also limited in our ability to examine nuances related to specific types and severity of chronic pain, characteristics of the prescribed opioid analgesics, and other unmeasured factors.

Among patients receiving methadone maintenance treatment in three Bronx clinics, nearly one-third reported taking prescribed opioid analgesics. Among these patients, chronic pain, prescribed opioid analgesic misuse, and illicit substance use were prevalent. Treatment of opioid dependence remains challenging, particularly given the burden of chronic pain and comorbid illnesses, and common use of prescribed opioid analgesics.

Acknowledgments

This study was supported by R01DA032110, K24DA036955, R25DA023021, K23DA027719 and the Center for AIDS Research at the Albert Einstein College of Medicine and Montefiore Medical Center (NIH AI-51519). The funding agencies had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Footnotes

Author Contributions: MCG contributed to data collection and writing the manuscript. NLS contributed to research conception and design, and revision of the manuscript. JLS contributed to revision of the manuscript. JM and JJJ contributed to data collection and revision of the manuscript. JHA contributed to research conception and design, and revision of the manuscript. COC contributed to research conception and design, data analysis, interpretation of results, and revision of the manuscript.

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