Ask the Expert: Dependence vs. Addiction
A patient with chronic low back pain has asked to be taken off her opioid. When asked why, she said it’s because she’s tired of her family telling her she’s just an addict. She is a compliant patient who has been taking 60 mg of sustained-release morphine twice a day for the past year. Over that time, she has been able to significantly improve her function, but, of course, she’s dependent on the opioid. She’s gone to physical therapy and she exercises regularly, and her urine drug test results have been good. What do I tell her?
First, chronic use of several classes of drugs, including some prescription drugs, results in physical dependence. The body adjusts to the ongoing presence of these substances such that when they are suddenly stopped, a specific withdrawal syndrome results. The withdrawal syndrome from abruptly stopping the antidepressant paroxetine (Paxil) includes nausea, dizziness, paresthesias, and anxiety and the withdrawal syndrome from suddenly stopping prednisone can be severe, and includes weakness, fatigue, hypotension, weight loss, nausea, and vomiting. Similarly, if the patient described above were to run out of her morphine, she would likely experience abdominal cramps, a runny nose, lacrimation, diarrhea, goose bumps, etc.
These withdrawal syndromes are physiological responses to the absence of the specific drugs. Simply tapering the drug, rather than stopping it abruptly, can prevent this condition. All physicians are aware of the need to taper prednisone if it has been prescribed in high dose for more than a few days. No one thinks that people who use paroxetine or prednisone chronically are addicted to those drugs. They are physically dependent on them.
Features of Addiction
Addiction is a different process. According to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV-TR),1 addiction (although they use a different term for it) has several features, most of them relating to pathologic behaviors. Characteristics of any addiction include:
- Loss of control (that is, taking the drug in larger amounts or over a longer period than intended).
- Continuing to take the drug despite significant adverse consequences;
- Preoccupation with obtaining, using, or recovering from the effects of the substance.
Usually all of these characteristics are present if the person is addicted.
The confusion regarding opioids arises because various drugs that can be abused, including opioids, can cause both physical dependence and addiction. Drug addicts not only exhibit the above behaviors, but they also are subject to a distinct withdrawal syndrome if they stop using their drug. They are both addicted to, and physically dependent on, their drug.
Opioid Use Disorder
Second, because the term “addiction” is considered pejorative, the authors of the DSM-IV-TR decided not to use the term at all—instead they substituted the word “dependence.” The term addiction never appears in the DSM-IV. Instead, the official designation for a heroin or prescription drug addict in the manual is “opioid dependent.” An unfortunate result of this is that if a physician, recognizing that his patient is on a high enough opioid dose (for example about 60 mg or more of morphine per day) to be at risk for withdrawal symptoms if he or she stopped the opioid suddenly, writes “opioid dependent” in the patient’s chart, another provider reviewing the chart is likely to conclude that he is dealing with a drug addict! This confusion of terms is why it is not possible to tell whether the writer of the above question, who asserts that his or her patient is “dependent” on her morphine, considers his patient to be addicted to morphine (which is very unlikely), or only physically dependent on it (extremely likely).
Fortunately, the recently published Fifth Edition of the DSM (DSM-5)2 has helped alleviate the “opioid dependence” confusion by renaming opioid addiction as “opioid use disorder.” The current reference book continues to avoid the word addiction, except the section on substance abuse is now termed “Substance-Related and Addictive Disorders.” At the beginning of this section the authors state: “The essential feature of a substance use disorder is a cluster of cognitive, behavioral, and physiological symptoms indicating that the individual continues using the substance despite significant substance-related problems. . . Overall, the diagnosis of a substance use disorder is based on a pathological pattern of behaviors related to use of the substance.
Regarding the actual diagnostic criteria, here is what the DSM-5 authors say about the only 2 physiologic criteria, tolerance and withdrawal. “This criterion is not considered to be met for those taking opioids solely under appropriate medical supervision.” In other words, developing tolerance to any opioid effect or experiencing withdrawal symptoms does not constitute addiction.
So what do I recommend for your patient? Explain to her, in layman’s language, that you do not believe that she is addicted to her morphine. Yes, she is physically dependent on her medication; therefore, she should not abruptly stop it. If her level of functioning has improved, her quality of life has improved, and she’s compliant, there’s no need to stop the medication. Suggest to her to bring her family members in with her on the next visit so that you can have this conversation with them as well.