Chronic Pain and Mental Health: Two Sides of the Same Coin

A recent study showed that those living with chronic pain are the largest group of people whose mental health needs are unmet. The findings have important implications for migraine, too.

Athletes and celebrities who speak openly of their own mental health struggles; articles about anxiety, depression, and post-traumatic stress disorder in prominent mainstream publications; frank and open conversations amongst friends and family about being in therapy – these are just a few examples of increased individual and societal recognition of mental health as a key aspect of a person’s overall health, meriting proper diagnosis and treatment.

Yet, surprisingly, the population with the highest level of unmet mental health needs – people with chronic pain – is largely overlooked in the mental health conversation, according to a new study.

Researchers led by Jennifer De La Rosa, University of Arizona Health Sciences, Tucson, US, found that US adults with chronic pain had greater mental health needs than the prevalence of chronic pain would suggest. They were also less likely to use mental health treatment compared to people with mental health needs who did not have chronic pain. And, when they did use treatment, they were more likely to have suboptimal outcomes compared to those without chronic pain who used treatment.

This population-based study, which relied on nationally representative data from the National Health Interview Survey (NHIS), further reported that those who had both chronic pain and mental health needs used mental health treatment less frequently, and had unremitted anxiety and depression more frequently, compared to those with mental health needs only.

“This study stands as a significant contribution to the pain research literature, particularly considering the lack of prior research using national-level data in the United States on mental health treatment in chronic pain,” wrote John Sturgeon, Maisa Ziadni, Zina Trost, and Afton Hassett in an accompanying commentary.

Considering that mental health issues are a co-morbidity of migraine, as well as the enormous problem of stigma that those living with migraine face, the time is ripe for the migraine field to grapple with the new findings, too.

The research and commentary appeared online ahead of print in July in the journal PAIN.

“A striking finding”
De La Rosa told Migraine Science Collaborative in an interview that the study builds upon her group’s previous work, which showed that almost 1 in 5 people with chronic pain had unremitted anxiety and depression, and that a bit more than half of people with unremitted anxiety/depression had chronic pain.

“That was a pretty striking finding that the majority of the unmet mental health need in the United States is associated with chronic pain,” she said.

But it was hard to understand why.

“So then the question was: Is this an access issue, or are they not getting benefit from treatment, or are they not getting the right treatment? What does it mean, and what can be done to intervene?”

To find answers, De La Rosa and colleagues then set their sights on the published literature in this area, but they didn’t find what they were looking for.

“The team and I went looking for studies on mental health treatment use among people with chronic pain, and we did not find any at the population level. There are some clinical studies, of course, and those are very important. But we didn’t have a way to characterize what’s happening at the population level in a way that could ultimately, we hope, influence policy.”

The team realized that they could use NHIS data to answer their questions, just as they had relied on NHIS data for their first study. The NHIS is an ongoing, decades-long effort to track the health of the United States population. Since 1957, this government interview survey of US households has asked adults 18 years or older living in the community about many different aspects of health.

Pain researchers like De La Rosa find NHIS a fruitful data source since it asks survey participants about how often they have pain, how severe the pain is, the anatomical areas in which participants are experiencing pain, and whether the pain interferes with daily living activities. However, NHIS does not contain information about specific diagnoses, or what mental health treatments may have been used.

Still, considering that head pain is one of the anatomic areas of pain included in the data, and that mental health is a big concern for those with migraine, as is stigma, the current study has clear relevance for the migraine field.

People with chronic pain bear a mental health burden
For their first analysis, the investigators looked at the need for mental health treatment, in the past 12 months, by a large population that they defined in their paper as the universe of people for whom mental health treatment would be a relevant treatment consideration.

Within that universe, roughly 39% of people with chronic pain had a mental health treatment need – even though those living with chronic pain comprise only 20% of the US adult population.

Along with that over-representation of need, only about 44% of people with chronic pain used mental health treatment and did not have unremitted symptoms of anxiety/depression, compared to almost 72% of those without chronic pain. That translated to roughly 15 million fewer people with chronic pain who used treatment and screened negative for those symptoms.

Further, amongst all of those with a mental health need, people with chronic pain were more than twice as likely to have used mental treatment and screened positive for anxiety/depression, compared to individuals without chronic pain: 37.2% of those in the former case (8 million people) versus 15% in the latter instance (5 million people).

Finally, what about people who did not use treatment and screened positive? Once again, in that group of people, those with chronic pain paid a mental health price, with 18% screening positive, compared to 13% of those without chronic pain.

Which results stood out the most to De La Rosa?

“For me, one of the starkest issues is that fewer than half of people with mental health needs and co-occurring chronic pain are getting what I would call the optimal treatment experience in terms of their mental health, compared with over 70% of people who have mental health needs but do not have co-occurring chronic pain,” De La Rosa said.

“There’s one more finding: Around 40% of people with mental health need – as we defined it in the country, so looking at all people in the country with mental health need – have co-occurring chronic pain. So they’re facing a huge disparity, and they’re very nearly a majority in the population of mental health need, and they are a majority in the population of people with unmet mental health need.”

Following the cascade
In the second part of their study, the researchers performed a different type of analysis that represented the data from a “cascade of care” perspective – think of the cascade as a healthcare journey from a mental health treatment need to a mental health benefit. The first step of the journey is to understand how many people have a need. Then, how many have a need and use treatment? Finally, how many have a need, use treatment, and screen negative for anxiety/depression?

The difference between the initial analysis and the cascade of care analysis is that, in the former instance, the researchers were looking at everyone in the population who had a mental health need. But in the latter instance, the researchers are following specifically those who stay in the cascade of care – who complete the journey from mental health need to an absence of symptoms.

The cascade of care analysis showed that 43% of those with chronic pain had a mental health treatment need, compared to just 17% of those without pain. At step two of the cascade, 82% of people with chronic pain had a mental health need and used mental health treatment, compared to 87% of those without pain.

Finally, at the last stage of the journey, only 44% of those who had chronic pain had a need, used treatment, and screened negative for anxiety/depression, compared to 83% of those without chronic pain.

Looking at the cascade of care data another way, among those with a mental health need, people with chronic pain had a 40% reduction in the odds of using treatment. And, those with pain who used treatment in the last year had roughly 4 times the odds of screening positive for anxiety or depression.

De La Rosa said, “We can see there’s a really high burden of mental health need [in those with chronic pain], and there’s a pretty evident failure to meet the need. So they’re facing a triple hazard: They’re having a higher hazard of mental health need, and they have a higher hazard not using treatment, and among those who do use treatment there is a higher hazard of not getting the outcome that we associate with the successes of the mental health movement today.”

Possible explanations to account for some of the findings, according to the study authors, include low awareness of why mental health is an important consideration for people with chronic pain; reluctance among patients to discuss mental health treatment because of stigma; and a lack of training in mental health by healthcare providers treating individuals with chronic pain, among other factors.

“The work left to do in mental health”
De La Rosa told MSC that her group is aiming to look at more fine-grained data, such as healthcare claims data, to better understand what explains the current findings. She also said she’d like to repeat the current study specifically for migraine.

She also pointed to the prospect of better patient care by improving how doctors and patients talk to each other.

“I think there’s an opportunity to work with people with lived experience on medical interactions around mental health and pain. And it’s very possible that there could be a model and a way of communicating that would be effective and helpful for people, and a way of talking about pain and mental health that would be validating, rather than the opposite. And if a model like that can be developed, I think there would be a lot of worth in trying to scale that out in clinician training and really address pain and mental health in a national way.”

Finally, when asked for take-home messages from her research, De La Rosa said this:

“That the mental health experiences of people with chronic pain are in some sense the work left to do in mental health. That if we have a lot of energy and enthusiasm around addressing mental health in this country, particularly in the post-pandemic landscape, we need to meaningfully engage the experiences of those with chronic pain.”

Neil Andrews is a science journalist and executive editor of the Migraine Science Collaborative.

References
The unmet mental health needs of U.S. adults living with chronic pain.
De La Rosa et al.
PAIN. 2024 Jul 30. Epub ahead of print

Scratching the surface: the complex interface of chronic pain and mental health treatment needs in the United States.
Sturgeon et al.
PAIN. 2024 Jul 12. Epub ahead of print

Image credit: Adobe Stock/melita