Opioids for chronic pain: Striking a balance
Less than half of al patients with chronic pain use opiods.
Pain is encountered daily in all health-care settings and is one of the most pervasive and expensive health problems of our time. This year, approximately 50 million Americans will have substantial acute pain related to surgery or trauma and more than 75 million more have chronic pain.1
The importance of effective pain management cannot be overstated given the negative impact it has on physical and mental health. Physically, pain can impair cardiac, respiratory, and immune functioning. It can disturb sleep, which creates health problems for those who are otherwise healthy. Pain worsens such illnesses as heart attack, cancer, and diabetes and interferes with recovery from surgery and injuries. In fact, the intensity of acute pain is the best predictor of which patients will still have pain one year after major surgery or trauma.2
Unlike acute pain, chronic pain has no known benefit and is now regarded as a disease state. The use of opioids for chronic pain is growing, although fewer than half of the estimated 76 million Americans living with this condition receive this form of treatment. The number of people with chronic pain is expected to increase as our population ages. Among those with pain, 42% of adults aged 20 to 65 years report having persistent pain, compared with nearly 60% of adults older than age 65 years who have endured pain for more than a year.1 There is a societal cost of pain as well, as it is a major cause of absenteeism and long-term disability. Even when patients with chronic pain continue to work, the cost to employers is more than $60 billion a year in lost productivity.3
Although less pervasive, estimates support that 16% of the general population has an addiction disorder, with many more who abuse or misuse drugs without having a frank addiction.4 Between 1999 and 2004, deaths linked to prescription drug use rose 160% whereas deaths related to motor vehicle accidents fell 6.5%. In some states, drug-related deaths exceed deaths from car accidents. Not all prescription drug-related deaths involve opioids, and most fatalities entail multiple drugs,5 yet media reports often mention only prescription pain relievers as a source of concern.
In 2008, nearly 5 million Americans reported using prescription pain relievers that were either not prescribed for them or used simply for the feeling the drugs caused.5 In too many cases, this nonmedical use results in serious health repercussions, including increased risk for illness, injury, overdose, and death. For the sake of the individuals directly affected as well as for the welfare and safety of our communities, health-care practitioners (HCPs) must address these public health problems. Well-intentioned HCPs who appropriately prescribe, dispense, and/or administer opioids to control pain must be aware of the possibility that patients may use the prescribed medication in a manner that the HCP did not intend.
While aberrant behaviors are often seen in patients with chronic pain, the reasons for these behaviors can be related to the unresolved pain, natural effects of the medicines, substance abuse, or addiction disorders. HCPs often jump to the conclusion that it is the latter,6 and patients are taken off of opioids or discharged from clinics and labeled as drug abusers or noncompliant with therapy. Meanwhile, the underlying problems may remain untreated, and the patient is left desperately seeking help using whatever coping skills he or she has. This has created a crisis for patients, prescribers, and communities that can no longer be ignored.
Barriers to optimal pain management with opioids
Although there are a few evidence-based guidelines for using medicines known to be effective for different types of chronic pain, the consistent application of these methods is lacking.7-9 Mistaken beliefs about pain and its treatment often interferes with optimal management. These beliefs range from unwarranted fears (e.g., assuming that all people on opioids become addicted) to a lack of concern among some patients about risks associated with high doses or unauthorized dose escalations. For patients, unrealistic expectations or misalignment between their goals and those of the HCP can affect adherence to the established treatment plan.
Unfortunately, many HCPs do not have the time to explore the patients' perspectives and may feel ill-prepared to correct them with facts. Many HCPs have never received sufficient or up-to-date information regarding pain. Even when a clinician has a good formal education in this area, research is rapidly changing awareness of the differences between acute and chronic pain. For example, during one recent month (September 2010), more than 300 articles on chronic pain were added to the growing literature base on Medline. These educational and clinical challenges make many HCPs feel inadequately prepared to identify and treat chronic-pain patients,10 especially if the person has a coexisting substance abuse or addiction disorder.11 As a result, the HCP becomes frustrated with this area of practice, and patients often express dissatisfaction with the treatment experience.11Barriers in the health-care system add to this frustration and dissatisfaction. Complex diagnostic coding and reimbursement structures currently used to classify and treat chronic-pain disorders are problematic. Payers may deny medical claims and refuse to pay for needed services, especially if mental-health diagnoses or services are involved. Reimbursement for and access to programs that teach how to cope with pain is often limited, and many candidates fail to pursue these therapies because of the stigma attached to accessing what is classified as psychological services. Other barriers include a shortage of specialists in pain therapy and in substance abuse and a dearth of providers who understand and can treat both problems. As a result, many chronic-pain patients seek treatment from primary-care clinicians or the emergency department or give up going to HCPs altogether.11,12
Establishing an opioids-sparing treatment plan
The optimal treatment plan for chronic pain patients is based on a comprehensive assessment that explores the physical, mental, emotional, and social changes that have occurred since its onset. Probes designed to reveal the underlying pathophysiology as well as pertinent thoughts, feelings, insights, activities, coping styles, and relationships help the HCP identify therapeutic targets. These targets become the basis for developing a comprehensive treatment plan that does not rely excessively on the use of opioids.13
Many people with mild pain can be treated without resorting to opioids by using cause-directed therapies, nonopioid analgesics, and adjuvant therapies. Those with moderate-to-severe pain can learn to cope and function at high levels without ongoing opioid therapy, but the therapeutic regimens involved are more complex and typically require multidisciplinary and/or multimodal approaches. Delving into strategies that help patients think, feel, and function better is beyond the scope of this article, but generally speaking, by treating only the underlying cause, the HCP may be missing opportunities to diffuse amplifiers of pain that may respond to nondrug therapeutic approaches.13
Determining whether the patient has somatic, visceral, or neuropathic pain may help target the underlying cause and guide the selection of adjuvant therapies. Somatic pain (e.g., arthritis and nonspecific low back pain) originates in the skin, muscles, bone, or connective tissue. Visceral pain (e.g., chronic unstable angina, chronic pancreatitis, and intestinal adhesions) results from diseases or injuries involving blood vessels, organs, or hollow viscera. Neuropathic pain results from damaged or malfunctioning nerves and is sometimes categorized as peripheral neuropathy (e.g., painful diabetic) or central neuropathic pain (e.g., poststroke, post-spinal cord injury), depending on which nerves are involved.
Nonopioid drug therapies that may help somatic pain include acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs). High doses and prolonged use of these agents produce considerable morbidity and mortality and thus have limited utility in some patients, especially those who are elderly or frail.8 Topically applied medications (e.g., capsaicin, diclofenac) may be beneficial and better tolerated but also have treatment-limiting side effects for some. For people with visceral pain or neuropathic pain, similar concerns exist about the safety of high-dose or long-term use of these nonopioid analgesics.
Acetaminophen may be the safest nonopioid, but the daily dose from all sources must be limited because of the potential for liver failure. The efficacy of acetaminophen may not be as good as that of other nonopioids for some painful conditions because of negligible anti-inflammatory effects. Despite concerns about morbidity with high-dose/long-term use, NSAID or steroid anti-inflammatory agents are often effective relievers of pain with somatic or visceral origins.