About two-thirds of addicted individuals had decisional capacity to provide consent to participation in research, a recent study found. Ethical considerations for this population include the following:
- Some treatment providers wrongly assume substance abusers are unable to give consent.
- Potential participants who present for a study while intoxicated or in acute withdrawal cannot provide informed consent.
- Researchers need to test appropriate treatments for the wide range of disorders that affect persons with substance use disorders as well as the general population.
When researchers assessed the capacity of addicted individuals to provide consent to research, they found that about two-thirds of participants had decisional capacity.1
“There is a big misconception that substance abusers are not able to make rational decisions, and therefore do not have the capacity to consent,” says William W. Stoops, PhD, associate professor at the University of Kentucky’s College of Medicine in Lexington.
Many treatment providers avoid obtaining meaningful consent from substance users, however. “The thinking is that their ‘disease’ makes consent impossible. There is no scientific evidence to support this idea,” says Robert Walker, MSW, LCSW, assistant professor of behavioral science at University of Kentucky Center on Drug and Alcohol Research.
Misconceptions about substance users’ capacity to give consent are commonplace among treatment providers, elected officials, and the general public, notes Walker. “However, among those who either do research or who are more experienced with these disorders, there is recognition that substance users can give consent both to treatment and to research,” he says.
There are ethical concerns involving enrolling any individual without decisional capacity in a research study regardless of whether they have a substance use disorder, says Barbara S. McCrady, PhD, director of the University of New Mexico’s Center on Alcoholism, Substance Abuse, and Addictions in Albuquerque.
“The one area of unique concern would revolve around an individual’s ability to understand research requirements related to substance use, need for ongoing care within a study, and understanding the limits of an experimental treatment,” says McCrady.
She gives the example of a long-acting form of naltrexone, an opiate antagonist administered as a monthly injection. When the medication is active, the risk of an opiate overdose is mitigated, but that effect lasts only about a month. “If a participant in a study of this medication does not understand that the injection is effective only for a month, he or she could be at risk for an opiate overdose without realizing it,” says McCrady.
Potential participants who present for a study intoxicated or in acute withdrawal cannot provide informed consent, notes McCrady. The long-term effects, particularly of alcohol, on comprehension and memory can also make it difficult to provide informed consent. “If a research protocol requires that participants abstain from the use of alcohol or other drugs, concerns about ability to sustain abstinence also have some merit,” says McCrady.
Counterbalancing these concerns, however, is the importance of developing and testing appropriate treatments for the wide range of disorders that affect persons with substance use disorders as well as the general population, says McCrady.
“To test treatments only on a non-affected population raises the specter of not knowing the potential risks and benefits of a treatment with a substance use disorder-affected population,” she says.
There are multiple important reasons to include persons with substance use disorders in scientific research, says McCrady. These include the following:
- to better understand the etiology, course, and resolution of these problems;
- to test potential prevention and intervention strategies;
- to understand the epidemiology of substance use disorders.
“Persons with substance abuse disorders often are excluded from biomedical research studies that are focused on physical and psychiatric illnesses other than substance use disorders,” says McCrady. Some reasons for this include the following:
- the possibility of alcohol or drug use complicating response to treatments being tested,
- • concerns about the number of co-occurring physical and psychological problems these individuals might have, and
- • concerns about the likelihood of the individual complying with experimental treatment regimes.
“Given the high mortality and morbidity rates among persons with substance use disorders, as well as the economic and social costs of substance use disorders, to exclude them from research would violate, at a minimum, the principle of justice,” says McCrady.
It is vital that researchers remain actively concerned with their research subjects and revisit informed consent with them throughout the research process, advises Stoops. This makes it possible to detect if an enrolled subject lacks capacity to consent.
“This shouldn’t be a standard just for research with substance abusers, though,” says Stoops. “It should be a standard for all research subjects.”
The University of Kentucky’s institutional review board’s procedure states that where subject capacity is impaired, a legally authorized representative must give consent to research either “in the person’s best interest” or as a “substituted judgment” about the procedure. “In the latter case, the legally authorized representative makes a decision as he or she thinks the person would have done, had he or she had decisional capacity,” says Walker.
Stoops says that excluding substance abusers from research, unless they would be harmed from participation, can violate the ethical principle of justice. This is especially true if substance abusers can benefit from the overall research findings.
“Of course, researchers need to ensure that substance users are able to provide consent to participate, and are not unduly influenced or coerced to participate,” says Stoops. Stoops uses the criteria of understanding, appreciation, reasoning, and expression of a choice when obtaining consent from the substance abusers he enrolls in research studies.
“Researchers enrolling substance abusers need to do their best to ensure participants have the capacity to provide consent, just as they would for ‘normal’ volunteers,” he says.
This could involve sobriety testing and an active discussion with subjects to assess their ability to meet criteria of understanding, appreciation, reasoning, and expression of a choice. “I could imagine a scenario where someone who lacks capacity to consent could slip through,” says Stoops. “But I would encourage investigators to put adequate safeguards in place to minimize this possibility.”
- Moran-Sanchez I, Luna A, Sanchez-Munoz A, et al. Decision-making capacity for research participation among addicted people: a cross-sectional study. BMC Med Ethics. 2016; 17(1):3.
- Barbara S. McCrady, PhD, Director, Center on Alcoholism, Substance Abuse, and Addictions, University of New Mexico, Albuquerque. Phone: (505) 925-2388. Fax: (505) 925-2301. Email: email@example.com.
- William W. Stoops, PhD, Associate Professor, University of Kentucky College of Medicine, Lexington. Phone: (859) 257-5383. Fax: (859) 257-7684. Email: firstname.lastname@example.org.
- Robert Walker, MSW, LCSW, Assistant Professor of Behavioral Science, University of Kentucky Center on Drug and Alcohol Research. Email: email@example.com.