The Devastating Overlap of Chronic Pain and Anxiety/Depression

Researchers have long been aware that people with chronic conditions (e.g. cancer, diabetes, arthritis) also tend to suffer from mental health issues like anxiety and depression. But how common the overlap is, and who it might affect, had not been well established.

Now, a new study from the University of Arizona Health Sciences Comprehensive Pain and Addiction Center shows that the co-occurrence of chronic pain and anxiety/depression is far more prevalent than previously understood. 

Thanks to an innovative analysis of general population data, the study shows that some 12 million U.S. adults — about 5% of the adult population — have co-occurring chronic pain and anxiety/depression symptoms: That's about 1 in 20 adults.

"Our findings made it possible to precisely characterize the nature and scale of co-occurrence in the U.S. adult population at large, which had not been done before," said Jennifer De La Rosa, Ph.D., the lead author of the study, in an interview. 

"It leaves no question that this co-occurrence is a major public health issue that should be part of mental health and pain advocacy movements," she said.

The study, "Co-occurrence of chronic pain and anxiety/depression symptoms in U.S. adults: prevalence, functional impacts, and opportunities," was published in March in the journal Pain. 

The researchers wanted to go beyond the studies of patient reports, and use a nationally representative data set to gain a deeper understanding of how mental health issues and chronic pain interact in the general adult population.

By analyzing data from the National Health Interview Survey, which De La Rosa describes as the most representative survey on health outcomes in the U.S. — with over 30,000 adults sampled annually — the research team was able to develop a more detailed picture of chronic pain and mental health issues. And what they found was eye-opening.

Roughly 24% of adults with chronic pain also suffer from clinically significant anxiety and/or depression symptoms — often abbreviated as A/D. That's nearly five times higher than the occurrence of anxiety/depression in people without chronic pain (4.9%).

This debilitating pattern goes both ways: Among adults with clinically significant anxiety/depression symptoms, over half also suffer from chronic pain (55.6%) — versus only 17% among those without A/D.

"The most important finding in my view is that people with unremitted anxiety/depression symptoms are more likely to have co-occurring chronic pain," De La Rosa said. "Which means, chronic pain is like an elephant in the room for resolving our national mental health crisis. That was not previously known."

"Culturally, in the United States, we tend to have a dualistic understanding of pain and mental health: pain is physical and mental health is emotional," De La Rosa added. "But for many people it's not one thing or another, it's both. And many people with these co-occurring conditions are systematically underserved by our health care system."

The University of Arizona study further supports what many patients, caregivers and clinicians already know: This co-occurrence can severely limit people's ability to hold down jobs, complete daily tasks (like running errands) or socialize with friends and family.

Some 70% of people with co-occurring symptoms reported difficulties doing their jobs; more than 55% said their social lives were impeded; and almost 44% were more likely to have difficulty doing errands alone.

For De La Rosa and her fellow researchers, this cross section of physical pain, mental distress and functional restrictions on daily life speak to a much greater point: 

In a health care system where acute symptoms are frequently treated separately, there is an urgent need for a more integrated approach both clinically and practically. "In the mental health conversation, we don't really talk about the fact that over half of people with mental health symptoms are experiencing chronic pain," she said. "It's more of a niche specialty.

"It would be so much better if we could engage in a way that's responsive, rather than tell people: 'Deal with pain with your physical health care provider — and deal with your mental health issues, over there with your mental health provider.'"

Although the U.S. health care system is notoriously siloed, the separation of treatment for mental health and chronic pain symptoms seems even more artificial — and baffling — when you know that both sets of symptoms "run along the same highway in the brain," as De La Rosa put it.

In other words, chronic pain and anxiety/depression are connected biologically. Certain regions of the brain are associated with how pain is processed and with anxiety/depression symptoms as well, including the insular cortex, prefrontal cortex, anterior cingulate, thalamus, hippocampus, and amygdala, according to the study. In addition, neuroinflammation is associated with both pain and anxiety/depression.

And yet, unlike many illnesses that can be assessed using objective tests, the evaluation of chronic pain and mental health symptoms depends wholly on reports from patients themselves. You can't use an MRI or a blood test to measure how depressed someone feels, or how much pain they are in. The lack of objective biomarkers makes these conditions hard to assess and even harder to treat.

"One of many things that's fascinating about pain is that reported symptom severity does not necessarily translate to how people function," De La Rosa said. "One person may report severe pain, but have very high functioning. Another person might report minimal pain, but have great difficulty functioning."

This subjectivity, so to say, has created another co-occurring condition for many people — which is the skepticism patients often face when trying to get help. Caregivers and health professionals alike may doubt or invalidate a patient's experience, or imply they aren't trying to get better, or worse that they're faking their symptoms.

This skepticism in turn can generate a kind of social stigma, which isn't helped by the persistence of these conditions. 

While most humans are wired to empathize when someone is in pain, sustaining a sense of sympathy over long periods of time is challenging. "It's very difficult to care about someone with a chronic condition, because you want to comfort them and have the symptoms go away," De La Rosa said. "But often in the case of chronic pain, the symptoms are not going away."

It's important to also understand the broader context for the University of Arizona study. The crossover between mental health symptoms with a number of chronic conditions is one that's well established, if not well understood.

According to data from Centers for Disease Control (CDC), as reported by Johns Hopkins University, not only do 51% of those with Parkinson's experience depression symptoms, so do 42% of cancer patients, 27% of diabetes patients, and 17% of patients with cardiovascular disease, among others.

The burning question is, why? Research suggests that chronic diseases themselves may generate clinical levels of anxiety or depression due to the sheer stress of having that condition, and all that it entails (i.e. physical and lifestyle changes, relationship challenges, financial strain, and so on). There also could be brain changes owing to a chronic illness. Or mental health issues could develop as a side effect of certain medications.

One thing that's clear, when taken as a whole, there is a pressing need to address mental health issues and chronic disease, including chronic pain conditions, using more integrated strategies.

• Integrate Communication. To that end, one of the most important adjustments that health care providers could make is to change how they communicate with one another, and with patients themselves, the study recommends. Granted, there are legal and privacy concerns that have to be met. But many medical professionals are starting to embrace a model of more integrated care, and patients benefit from this holistic approach. “Doctors need to communicate with each other,” De La Rosa said. 

• Prioritize Mental Health. In many cases, De La Rosa said, screening for mental health symptoms, or even asking about a person’s wellbeing, is the last thing providers examine. “It would be great if mental health could be addressed at the beginning, rather than at the end of an exhaustive biological investigation as to what may be causing the pain,” De La Rosa noted.

• Remediate Burnout. Because chronic pain and mental health symptoms are so persistent over time, which can strain empathy for patients, it’s essential for caregivers and professionals to find effective ways to address what is, in effect, a type of burnout. 

This carries over to how patients are treated as well. "One of the most important things a provider can say to a patient is, 'I believe you,' because of the invalidation patients may have experienced before," De La Rosa said.

M.P. Dunleavey writes about life and money, as she has for many years, in countless publications (and a book). She lives in New York City with her family and two cats. Read More