WHO Recognizes Chronic Pain as Disease With New Coding System

By Pat Anson, PNN Editor

The World Health Organization has adopted a new classification system for chronic pain, assigning it the code ICD-11 in a revision of the International Classification of Diseases (ICD). It’s the first time the ICD will include a specific diagnostic code for chronic pain, along with sub-codes for several common chronic pain conditions. 

The new classification system is important because it treats chronic pain as a distinct health condition and as a symptom to an underlying disease. It also takes into account the intensity of pain, pain-related disability, and psychosocial factors that contribute to pain.

“The inclusion of the new classification system for chronic pain in ICD-11 is an important milestone for the pain field,” says Lars Arendt-Nielsen, MD, President of the International Association for the Study of Pain (IASP), which headed a task force that developed ICD-11.

The new coding system will make it easier for physicians to diagnose, classify and get treatment for chronic pain patients. Insurers will use the new codes to authorize payments and researchers can use them to more easily track and measure the effectiveness of therapies. That’s the good news. 

The bad news is that the ICD changes won’t formally take effect until January 1, 2022. 


Under the current system, chronic pain conditions are poorly categorized under the code ICD-10, which makes it difficult for complex conditions such as fibromyalgia and Complex Regional Pain Syndrome (CRPS) to be classified. That led some physicians to diagnose patients with unexplained pain as having a somatic symptom disorder. 

“A diagnosis of somatic symptom disorder implies that the pain is caused by a behavioral, that is, mental condition. However, it is not appropriate to diagnose individuals with a mental disorder solely because an alternative medical cause cannot be established,” Jaochim Scholtz, MD, an IASP task force member, explained in Practical Pain Management.  

Under the new coding system, patients with fibromyalgia or CRPS could be classified as having a “primary pain” disorder, one of seven new sub-codes for chronic pain conditions:

  1. Chronic primary pain

  2. Chronic cancer-related pain

  3. Chronic post-surgical or post-traumatic pain

  4. Chronic neuropathic pain

  5. Chronic secondary headache or orofacial pain

  6. Chronic secondary visceral pain

  7. Chronic secondary musculoskeletal pain.

There is some overlap between the different diagnostic codes. For example, neuropathic pain can be a symptom of cancer or chemotherapy, while trigeminal neuralgia could fall under neuropathic or orofacial pain. The idea is to give physicians a range of codes to choose from instead of the limited choices they have today.

“The integration of chronic pain in ICD-11 sends a strong signal that pain will achieve appropriate representation in this international standard for reporting diseases and health conditions,” said Scholtz. “The coding system also provides fundamental information for the identification of health trends and healthcare planning. It is widely hoped that the new systematic classification of chronic pain in the ICD-11 will support epidemiological, and other research that is essential for the development of future health policies.”

The classification system was outlined in a free online article published in the January 2019 issue of PAIN.

How An Overdose Can Be Wrongly Reported

By Rochelle Odell, Guest Columnist

I started researching government statistics on overdose deaths a few weeks ago and learned the data is compiled by the Healthcare Cost and Utilization Project (HCUP), which is part of the Department of Health and Human Services.

HCUP keeps databases of ICD codes (International Classification of Diseases), which are built from hospital billing records. Basically, the codes identify what someone was being treated for at the hospital at the time of their death.

I realized that the ICD coding often begins when a person first enters the healthcare system (i.e. a trip to the emergency room or admission to a hospital). I also noticed that ICD codes for opioid overdoses do not separate the legal use of opiates from illegal drug use.

Then I learned that if a person dies, it could be months before the final coroner's report comes out. Does the government go back and change the ICD codes once the actual cause of death is determined?

Unfortunately, they do not.

So it all boils down to whether a person has opiates – any kind of opiate -- in their system at the time of death. If they are a chronic pain patient, there’s a good chance they will have opioid pain medication in their system. But rather than focusing on the true cause of death, everyone seems to immediately assume it was the medication.

I brought the point up with HCUP and told them their numbers were flawed and why. I was surprised to receive a nice email in response, validating my concerns and stating they would be passed along to the correct agency, the National Center for Health Statistics (NCHS).

“We will forward your email to NCHS to see if anything can be done to make the separation between illicit and licit use clearer in the coding,” HCUP replied.

If a citizen can find these flaws in a short time why can't anyone else? And how do I know if my concerns were truly shared and who received them?

As pain patients, we need to ensure that our families are aware that if we die from something unrelated to opiates, they’ll need to advocate for us even in death. Just finding opiates in our system does not mean we died of an overdose.

A good example of what could go wrong – and misreported -- happened earlier this month. A neighbor told me she had been walking her little dachshund when she stopped by a friend's house. The door was ajar, but there was no response. She sends her dog in and gets him to bark. At that point, her friend finally woke up. She had apparently suffered a stroke!

They called 911 and my neighbor waved down the ambulance as it approached. Her friend is in her 60's and right away the EMT verbally stated "it must be an overdose."

My neighbor immediately corrected the EMT and said her friend was not on pain medication and that this was not an overdose.

If my neighbor had not been there to set them straight, her friend may have been taken to the hospital and given the ICD code for a suspected overdose. The code could have followed her throughout her stay at the hospital, and if she had died, her death may have been wrongly reported as an overdose.

We need to stop this nonsense at step one.

Rochelle Odell lives in California. She suffers from Complex Regional Pain Syndrome (CRPS).

Pain News Network invites other readers to share their stories with us.  Send them to:  editor@PainNewsNetwork.org

The information in this column should not be considered as professional medical advice, diagnosis or treatment. It is for informational purposes only and represents the author’s opinions alone. It does not inherently express or reflect the views, opinions and/or positions of Pain News Network.