A new study is reviving an old debate about chronic pain: How many Americans have it?
A report published this week in The Journal of Pain estimates that 39 million people in the U.S. have persistent or chronic pain – far less than the 100 million reported by the Institute of Medicine (IOM) in its landmark 2011 study “Relieving Pain in America.”
Other estimates have placed the number of people in pain at 50 million or 70 million.
Why does it matter? As we reported a couple of years ago, the “numbers game” can be used by all sorts of special interest groups – the pharmaceutical industry, drug screening companies, non-profit pain organizations, healthcare providers, addiction treatment centers and anti-opioid groups – either to exaggerate or downplay the need for more chronic pain treatment and research.
The idea that over one in three Americans suffers from chronic pain – as claimed by the Institute of Medicine – was called “ridiculous” by Dr. Andrew Kolodny, president of Physicians for Responsible Opioid Prescribing, a group that lobbies against the overprescribing of narcotic pain medications.
“This was language that was lobbied for by the pharmaceutical industry and by organizations funded by industry. They wanted a report on chronic pain because they knew it could be used in advocacy for opioids or other treatments and ultimately they got the report that they wanted,” Kolodny told National Pain Report.
The IOM originally estimated that 116 million people were in pain, before discovering a “computational error” and quietly revising its estimate a few months after its report came out. Despite the correction, the discredited 116 million figure still turns up occasionally, as you can see here and here.
One reason the number varies so widely is the different ways that chronic pain is defined and where the data comes from.
The Journal of Pain study, which was conducted by researchers at the Washington State University College of Nursing, looked at data from a 2010 survey of over 35,000 households by the National Center for Health Statistics. It defined persistent or chronic pain as frequent or constant pain felt “every day” or “most days” in the preceding three months.
“Older adults, women, Caucasians, and people who did not graduate from high school are all more likely to report frequent or constant pain lasting 3 or more months, as are adults who are obese, who describe their overall health as fair or poor, and who have been hospitalized in the past year,” wrote lead author Jae Kennedy, PhD, a professor in the Department of Health Policy and Administration, Washington State University.
About 19% of the adults who were surveyed reported persistent pain when they were interviewed in 2010 — which is how the 39 million estimate was arrived at.
But over half the adults who had lower back pain, severe headache or migraine, or neck pain said their pain was not persistent – so they were not counted among the 39 million. People with neuropathic pain or muscle pain were also excluded if they didn’t report persistent back pain or headaches.
The Institute of Medicine took a different approach to the numbers and cast a much wider net — defining “persons with pain” as anyone who reported severe or moderate pain, joint pain, arthritis or pain that interfered with their ability to work or do household chores during the previous four weeks. It then used data from a 2008 federal health survey of over 20,000 adults to reach its estimate of 100 million.
Three years later, the IOM is still defending that estimate.
“The report’s estimate of the number of US adults affected by chronic pain has generated debate among researchers and policy makers that sometimes has distracted attention from the development of an effective public health response,” wrote Victor Dzau, MD, an IOM member, in an op-ed piece recently published in JAMA, the Journal of the American Medical Association.
“Although the IOM stands behind the estimate that 100 million Americans have chronic pain, the committee’s recommendation that better data are needed to help shape these efforts should also be underscored.”