One of the biggest barriers affecting people live with chronic pain is not being taken seriously or believed – particularly if the pain has an invisible cause. This barrier can result in lack of proper medical care and understanding among friends, coworkers and even family members.

In 1979, the International Association for the Study of Pain (IASP) defined pain as “An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.” While this definition may have described acute pain, such pain from a broken ankle, surgery, or an infection, it doesn’t cover the many types of chronic pain experienced by over 50 million adults in the United States. Now, 41 years later, the IASP has issued a new pain definition: “An unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage.” The revised definition is close to the original, but with an important difference. It acknowledges that chronic or ongoing pain may not cause tissue damage at all, yet the pain continues.

Why Change the Definition?

“We hope that the revised definition and accompanying notes will be useful in increasing patients’ and healthcare providers’ understanding of pain as a sensory and emotional experience that may or may not be associated with tissue damage,” Judith A. Turner, PhD, a professor at the University of Washington, in Seattle, told Medical Daily. “If this understanding is shared by patients and their providers, patient-provider communication and agreement on optimal treatment can be improved."

It’s important for people living with pain, she said, along with their family and their healthcare providers to all understand that pain can result from factors other than tissue damage, which is what the original definition said. “Pain is just as “real” as the pain caused by tissue damage. [It] is influenced by biological and psychosocial factors, and these influences need to be assessed and targeted by treatment.”

This revised definition also aims to help the patient discuss pain issues. "The task force hopes that the revised definition will encourage the person in pain to convey a more complete picture of the adverse effects of their pain to their care providers," Srinivasa N. Raja, MD, explained to Medical Daily. Raja is Chair of the IASP Task Force and Director of Pain Research, Professor of Anesthesiology & Critical Care Medicine, Professor of Neurology, Johns Hopkins University School of Medicine. "Similarly, we anticipate that the revised definition may lead the clinicians to not only listen to the patient's complaints of pain, but also to enquire how the individual’s pain interferes with their daily activities, quality of life, relationships, and social interactions. This information will help develop a personalized, multi-disciplinary, patient centered pain management strategy."

There had been some criticisms of the 1979 IASP definition because it ignored the many ways the mind and body interact and that the definition neglected “the ethical dimensions of pain,” Raja said. In addition, Raja pointed out that many believed the earlier definition emphasized verbal self-report and excluded non-verbal behaviors in disempowered and neglected populations, such as newborns and the elderly, as well as in animals."It [also] did not take into consideration the cognitive and social factors critical to the pain experience. Finally, research in more recent years has indicated that some types of pain may not be associated with tissue injury and may be associated with nervous system dysfunction."

Common Causes of Chronic Pain

Chronic pain has many causes, but the most common in the U.S. include:

  • Headaches and migraines
  • Back pain
  • Cancer
  • Arthritis

There are also syndromes, like fibromyalgia or phantom limb pain, a group of symptoms and signs that together define a disease or disorder, that have no obvious source and yet, they can cause debilitating pain.

Treating chronic pain is difficult and often takes some trial and error to find treatment that works. But before diagnosis and treatment, healthcare providers must recognize the effect of pain on their patients and that to the patients, the pain is real whether they can see it or not. “Pain is a personal experience that can be influenced by biological factors not limited to tissue damage, the individual’s thoughts and feelings, and social factors,” Turner explained. “It can be felt in a part of the body that is not actually involved in generating the pain experience.” Like lower back injuries that can make your sciatic nerve, that thick nerve that runs on either side of you from your hips down to your knees, hurt.

Pain can and does save lives. It tells us when things aren’t right with our body and it can keep us from doing dangerous things, like putting our hand on a hot surface. But when pain – specifically chronic pain – is debilitating, it often affects quality of life both physically and mentally. It does so, regardless of whether the pain is visible or not.

"An important take home message [from the new definition] for a person with pain is that to help their care provider in planning the optimal pain treatment, [the patients] should provide a comprehensive history of their pain symptoms as well as how the pain interferes with their daily function, work, relationships and societal interactions," Raja said. This can help the provider examine a variety of inter-disciplinary approaches to manage the pain, which could include non-addictive medications and other treatments, such as cognitive behavioral therapy, physical and occupational rehabilitation, and interventional approaches such as nerve blocks and neuromodulation.

Edited July 21, 2020, to include quotes from Dr. Raja.