Up to 30% of patients for whom opioids are prescribed for chronic pain show an escalating pattern of opioid abuse characterized by taking more opioids than prescribed, seeking early refills, and finding additional sources of opioids. Although many of these drug-seeking patients are addicted to opioids, some are suffering not from addiction but from inadequate pain management, according to Martha Wunsch, MD, chair of Addiction Medicine and associate professor of pediatrics at Edward Via Virginia College of Osteopathic Medicine (VCOM) in Blacksburg.
Wunsch makes a point of underscoring the prevention, recognition, and treatment of prescription opioid abuse in the patient with chronic pain. She did so last year at the 2006 annual meeting of the American Academy of Neurology (AAN). The topic bore directly on the everyday work of her audience at the AAN meeting; the majority of neurologists care for patients with nonmalignant chronic pain (NCP) including headache, neuropathy, "failed back" syndrome, postherpetic neuralgia, and regional pain syndromes.1 Patients with NCP often require prolonged treatment with opioids, but neurologists and other physicians frequently hesitate to prescribe these drugs. Topping their list of concerns is drug addiction.
PAIN MED CONSIDERATIONS
Drawing on the universal precautions in pain medicine suggested by Gourlay and colleagues,2 Wunsch, in an interview with Applied Neurology, outlined the steps that neurologists should take with all patients treated for pain syndromes, particularly those being considered for a trial of opioid treatment. These consist of a psychological assessment including past and present substance abuse, a treatment agreement clarifying the expectations and obligations of both patient and clinician, regular assessment of pain level and function, and periodic urine drug screens.
Wunsch also pointed to the importance of using tamper-resistant prescription packaging and protecting prescriptions—not just storing the pads in locked containers but also writing quantities and strengths in both numbers and letters. Simple measures such as asking the patient to designate one pharmacy and telling patients to store their medication in a locked box can go a long way toward reducing drug diversion, noted Wunsch.
Wunsch's colleague, Don H. Bivins, MD, associate professor and discipline leader of neurology at VCOM, commented that the potential for opioid abuse among patients is less of a problem than what he called an "epidemic of pain undertreatment." Neurologists and other physicians hesitate to prescribe powerful opioids in sufficient doses, he said. They worry about legal action and drug diversion as well as about addiction. Their qualms are not unfounded, however. Doctors who write large numbers of opioid prescriptions are targeted by the Drug Enforcement Administration for investigation. But what should be of greater concern to those who watch over medical care, said Bivins, is "not the overuse of opioids but their inappropriate use." Bivins feels that all physicians—and neurologists in particular—could benefit from education in pain medicine.
TRAINING IN PAIN CARE LACKING
Despite that neurologists are uniquely qualified to appreciate the neurobiology of pain and that they encounter a substantial number of patients with NCP, they receive little training in pain management. Few neurology residency programs offer training in pain medicine. As a result, Bivins said, neurologists are often insecure in managing pain patients and reluctant to care for them. Many choose to refer their patients with NCP to pain clinics or pain specialists. But the "anesthesiology model" often applied in pain clinics and by pain specialists—which relies on injectable analgesics—does not always meet patients' needs.
When neurologists and other clinicians do end up caring for patients with NCP, they often undertreat the pain and inadvertently set the stage for opioid abuse. The universal precautions in pain medicine outlined by Wunsch can go a long way toward reducing the likelihood that the patient for whom an opioid is prescribed will end up with opioid abuse or addiction, Bivins remarked. He stressed the importance of substance abuse history and advised neurologists considering a course of opioid treatment to ask patients not only about illicit drug use but also about alcohol(Drug information on alcohol) use and cigarette smoking. Patients who have smoked cigarettes or used alcohol in more than moderate amounts, as well as those who have used illicit substances, are prone to prescription opioid addiction, he said. Bivins noted that the brain circuits involved in pleasure and reward underlie this addiction proneness. According to him, such patients should not be denied opioid treatment, but they do require extra vigilance.
ADDICTION: DEFINITIONS AND SIGNS
The definition of opioid addiction offered by the American Society of Addiction Medicine—a definition to which Wunsch subscribes—focuses not on physical dependence and tolerance, which are normal consequences of opioid treatment, but on aberrant behavior: lack of control over opioid use, compulsive opioid use even in the face of negative health and social consequences, and preoccupation with obtaining and using opioids. Thorough assessment of the patient's pain and pattern of drug use can help distinguish pseudoaddiction from true addiction. Typically, when the pain is adequately treated, the "addiction" stops.
Neurologists should be alert for addiction in any chronic pain patient who also suffers anxiety and depression, said Wunsch. Other red flags for addiction are "noncompliance, frequent absences from work or school, labile hypertension, and sleep disorders." A study of patients with chronic pain, cited by Wunsch, showed that 3 factors distinguished patients who became addicted to prescribed opioids: escalation of dose or frequency, preference for a mode of administration, and the patient's belief that he or she is addicted.3
Although a history of substance abuse identifies the patient with NCP who is at particular risk for opioid abuse and attention to the red flags can help the clinician spot addiction, a substantial minority of the patients who become addicted escape notice. It is estimated, for example, that 10% to 25% of patients with NCP who become addicted to prescribed opioids have no history of substance abuse or addiction.4 For this reason, both Wunsch and Bivins emphasize that universal precautions in pain medicine should be applied to all patients treated with opioids.