What you need to know
Researchers looked at all studies that examined methamphetamine use and its impact on people who are using medications for opioid use disorder (MOUD). The analysis compared people on MOUD who used methamphetamine and those who did not. All studies showed that patients were more likely to discontinue MOUD treatment if they used methamphetamine. Those who used methamphetamine more often were more likely to discontinue MOUD treatment than those who used it less often. There are limited treatment options for individuals who use methamphetamine and opioids together, so emphasis should be placed on developing, implementing and evaluating such services.
What is this research about?
Opioid use has been growing over the past decades in North America, resulting in a record high number of drug poisoning deaths. There has also been an increase in the use of stimulant drugs such as methamphetamine and cocaine.
In North America, medications for opioid use disorder (MOUD) usually include methadone with or without buprenorphine and naloxone. MOUD has been shown to reduce substance use, drug-related crime, risk of illnesses such as HIV and hepatitis C, and death.
People who stay on MOUD have a lower risk of using drugs, being hospitalized, engaging in criminal activity and dying. However, few people with opioid use disorder start this treatment, and less than half of those who do continue for longer than six months.
Given the rise in methamphetamine and opioid co-use, the related morbidity and mortality, and the importance of staying on MOUD, researchers decided to examine the potential impact methamphetamine use might have on the likelihood of continuing MOUD.
What did the researchers do?
The researchers looked at all studies that examined methamphetamine use. Studies were included if all participants were receiving MOUD. The analysis compared two groups: individuals who were using methamphetamine and individuals who did not use methamphetamine.
What did the researchers find?
They identified eight studies. All studies showed that patients receiving MOUD were more likely to discontinue treatment if they used methamphetamine. Those who used methamphetamine more often were more likely to discontinue MOUD than those who used it less often.
The researchers note that given the ongoing and evolving opioid poisoning crisis, MOUD services need to identify clients who use methamphetamine as it is an important risk factor for dropping out of treatment. Those who use both methamphetamine and opioids should be encouraged to start MOUD and should receive education on the increased risk of dropping out of treatment. There are limited treatment options for individuals who use methamphetamine and opioids together, so emphasis should be placed on developing, implementing and evaluating such services.
Limitations of the research
The researchers identified several study limitations. The analysis included a small number of studies. The studies also used different measures of methamphetamine use, and no studies examined co-occurring opioid and methamphetamine use disorder. In addition, MOUD formulations and programming were different from one jurisdiction to another.
How can you use this research?
This study has useful information for substance use program planners and service providers as it offers valuable insights into the need to provide services for people who use both methamphetamine and opioids. It also highlights the need to develop, implement and evaluate effective and accessible services for people who use methamphetamine and opioids together.
About the researchers
Cayley Russell1, Justine Law1, Sameer Imtiaz1, Jürgen Rehm1,2,3,4,5,6,7, Bernard Le Foll3,8,9,10 and Farihah Ali1
- Centre for Addiction and Mental Health (CAMH) & Ontario Node, Institute for Mental Health Policy Research, Canadian Research Initiative in Substance Misuse, Toronto, Canada
- Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
- Institut Für Klinische Psychologie Und Psychotherapie, Technische Universität Dresden, Germany
- Department of International Health Projects, Institute for Leadership and Health Management, Moscow, Russia
- Center for Interdisciplinary Addiction Research, Department of Psychiatry and Psychotherapy, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Department of Pharmacology and Toxicology & Department of Family and Community Medicine, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
- Translational Addiction Research Lab, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Waypoint Research Institute, Waypoint Center for Mental Health Care, Penetanguishene, Ontario, Canada