While research during the past decade has led to a greater understanding of pain, more effective pain-relieving medications and strategies are still needed, experts say.
One of the most common reasons for seeing a physician, chronic pain is estimated to affect 20% of the world's population.
A series of three articles and a linked commentary published June 25 in The Lancet focus on treatments for postoperative pain, chronic noncancer and cancer-related pain, and the "important" role clinicians play in pain management.
In the first article, Christopher Wu, MD, and Srinivasa Raja, MD, of Johns Hopkins University and School of Medicine in Baltimore, Maryland, review the progress made in treating postoperative pain during the past decade. They stress that despite advances in pain management, many patients continue to experience moderate-to-severe pain after surgery.
Inadequate postsurgical pain management is not just limited to adults; the researchers site one study from the United States that showed that as many as 86% of children experience significant pain on the first day home after undergoing routine tonsillectomy.
"It is not clear why postoperative pain continues to be undertreated," Dr. Wu told Medscape Medical News. "However, as we mention in our article, the reasons for this are most likely mutlifactorial, including continued paucity of pain assessment and documentation, heightened awareness, and increased number of audits or surveys leading to increased identification of undertreatment of pain."
Deficiencies in educational pain management programs for healthcare workers, underuse of effective analgesic techniques, and poor adherence to available guidelines are also likely reasons, the researchers note.
"The use of more effective analgesic techniques, including regional analgesia and multimodal analgesia, should be considered in patients scheduled for a surgical procedure," said Dr. Wu. The use of regional analgesia techniques in some cases, such as high-risk procedures or high-risk patients, may also be associated with a decreased in perioperative morbidity, he added.
Prevalent and Costly
The second article focuses on the treatment of chronic noncancer pain, which is "prevalent and costly," first study author Dennis C. Turk, PhD, told Medscape Medical News.
In the United States, estimates for the total cost of chronic pain top $210 billion annually, he points out. The United Kingdom spends an estimated $26 billion to $49 billion annually on chronic back pain alone.
Dr. Turk is director of the Center for Pain Research on Impact, Measurement, & Effectiveness at the University of Washington in Seattle and serves as editor-in-chief of the Clinical Journal of Pain.
In their article, Dr. Turk and colleagues provide a general overview of empirical evidence for the most commonly used pain interventions in chronic noncancer pain.
"None of the currently available treatments — pharmacological, surgical, physical, complementary, or psychological — are adequate to mitigate the problem of pain in the majority of patients," Dr. Turk told Medscape Medical News. Across treatments, the results of clinical trials demonstrate that fewer than 50% of patients receiving the treatment will average more than 30% to 40% reduction in pain, he added.
Echoing Dr. Wu's comments, Dr. Turk believes that "combination treatments should be considered, and this is commonly the case in medical practice, although research on the additive benefits is limited and results are inconsistent."
What's needed, Dr. Turk says, is "research to identify the characteristics of patients most likely to benefit from different treatments, compared to what alternatives, provided when, and at what costs."
Some attitude adjustment may also be in order.
"Pain," said Dr. Turk, "has traditionally been viewed as a symptom of a disease or injury and of secondary interest, in comparison to diseases associated with the symptoms per se. This has led to inadequate attention to pain."
The available and growing research, he added, indicates that chronic pain is a complex phenomenon that is influenced by genetic, neurophysiological, psychosocial, and behavioral factors.
"Pain occurs in an individual, with a history, living in a social context and not in a body part or system in isolation. Typically, treatment approaches have been quite narrow, not attending to the range of factors involved. Patients with the same diagnosis tend to be treated in the same way, as if they were a homogeneous group. The heterogeneity has not been adequately taken into account."
One problem, Dr. Turk says, is that much of the research on pain treatments has been conducted by pharmaceutical companies and device manufacturers, who have little incentive to identify subgroups of treatment responders because this might limit their markets.
"What we have learned about the complexity of chronic pain has not been translated into clinical practice. Moreover, insurance coverage and payment for necessary comprehensive treatments has been inadequate, failing to appreciate the complexities involved," Dr. Turk said.
Cancer Pain Often Uncontrolled
The third article in the series deals with the management of chronic pain in patients with active cancer.
The study author, Russell K. Portenoy, MD, of the Department of Pain Medicine and Palliative Care at Beth Israel Medical Center in New York City, notes that guideline-based pain management care in this group of patients "yields satisfactory relief for most patients."
Yet, it is estimated that 43% of cancer patients receive inappropriate care for their pain.
The mainstay of treatment is opioid-based drug therapy, and all clinicians "should aim to optimize the positive outcomes from these drugs and minimize the risks," Dr. Portenoy writes.
When opioid treatment is not sufficient, adding a nonsteroidal anti-inflammatory drug to opioid therapy can be helpful, he notes, particularly in some painful conditions, but the gastrointestinal, cardiovascular, and renal risks of these drugs needs to be weighed against their benefits on a case-by-case basis. Other drugs, such as glucocorticoids, antidepressants, and anticonvulsants, may also be helpful.
"Nonpharmacological treatments can be used to improve pain control, coping, adaptation, and self-efficacy; mind-body strategies have established benefit and can be used in a restricted but potentially useful manner by nonspecialists," Dr. Portenoy writes. Interventions such as neural blockade and implanted therapies play a "small but important" part in the management of refractory pain, he writes.
Dr. Portenoy says there is growing recognition of the benefits of integrating palliative care into the management of cancer pain. The palliative care model "applies throughout the course of the illness and includes interventions that are intended to maintain quality of life, mitigate suffering, and improve coping and adaption by reducing the burden of illness and supporting communication, autonomy, and choice," he explains. Ideally, it should be discussed and implemented early in the course of illness, he adds.
Palliative Care a Human Right
In a linked commentary, The Lancet editors note that, earlier this month, Human Rights Watch drew attention to this issue in a report, Global State of Pain Treatment: Access to Palliative Care as a Human Right.
The agency surveyed palliative care experts in 40 countries and analyzed information on opioid use in these countries. They found that 14 countries reported no use of opioid pain medication between 2006 and 2008 and 13 other countries didn't use enough opioid drugs to even treat 1%.
"Clinicians have an important part to play in advocating for improved access to opioid drugs for medical purposes, as well as in managing pain effectively," the study authors write.
"Keeping up to date with the latest advances in treatment and adhering to pain management guidelines should be standard practice, but, as the series shows, the reality can be very different....To help eliminate or mitigate a individual's pain is a privilege that clinicians must neither forget nor neglect."
Dr. Wu has disclosed no relevant financial relationships. Dr. Turk has received grants from several pharmaceutical companies, including Endo Pharmaceuticals and Ortho-McNeill Janssen, and has served as a consultant to Endo Pharmaceuticals, Galderma, Pfizer, and Smith & Nephew. Dr. Portenoy has received consultancy fees from several pharmaceuticals, including CNSBio, Covidien Mallinckrodt, Grupo FeErrer, King Pharmaceuticals, ProStrakan Pharmaceuticals, and Purdue Pharma. A complete list of author disclosures can be found with the original articles.
Lancet. 2011;377:2215-2225, 2226-2235, 2236-2247, 2151. Abstract 1 — Abstract 2 — Abstract 3 — Commentary
Megan Brooks • Medscape Medical News © 2011 WebMD, LLC