Evidence-based strategies for treating chronic pain

Chronic pain and psychological distress are on the rise in the United States. (CDC, 2019; Case and Deaton, 2015). Unfortunately, pain is a challenging public health issue complicated by opioid prescribing practices and sociodemographic disparities (Grol-Prokopczyk, 2018).

In this installment of Research Roundup, we look at new studies exploring personal resources, relationships, and coping methods of patients who experience pain and how these factors can inform psychologists’ development of treatment plans.

Mun, C.J., Davis, M.C., Molton, I.R., Karoly, P., Suk, H.W., Ehde, D.M., . . . Jensen, M.P. (2019). Personal resource profiles of individuals with chronic pain: Sociodemographic and pain interference differences. Rehabilitation Psychology, 64(3), 245–262. http://dx.doi.org/10.1037/rep0000261

For individuals with chronic pain, their personal resources, rather than their pain intensity, often predicts what impact the pain has on their daily lives (pain interference). Modifiable personal resources include sense of resilience, social support, pain acceptance, and sleep quality.

Identifying groups of individuals based on profiles of personal resources can help clinicians to develop personalized chronic pain treatment plans. To that end, Mun et al. looked at two separate samples of individuals to identify different personal resource profiles/groups, explore sociodemographic differences between the groups, and examine group differences in pain interference.

Study 1 focused on 220 individuals with fibromyalgia who tracked their pain, physical, psychological, and social experiences on a digital diary for 21 days. Study 2 examined the annual survey results of 483 individuals with long-term neurological/neuromuscular disease or injury and chronic pain over a four-year period. Both studies measured participants’ modifiable personal resources to create subgroup classes.

The authors identified three subgroups of individuals with pain in both studies: High, Moderate and Low Personal Resource groups. Analyses found that people in the Low Personal Resource groups had significantly lower annual income than those in the other two groups.

In Study 1, while there were some depressive symptoms reported by individuals in all three subgroups, only participants in the Low Personal Resource group reported symptom levels that met the criteria for diagnosis of clinical depression. When the researchers controlled for pain intensity and depressive symptoms, they found no differences in levels of pain interference over the 21 days between the High and Low Personal Resource groups. However, the Moderate group displayed significantly higher levels of pain interference than the High Personal Resource group.

In Study 2, all three personal resource groups differed in their levels of pain interference at the beginning of the study, with the Low Personal Resource group reporting the most pain interference. These differences remained stable across the four years of the study.

Clinical implications

Based on these findings, the authors recommend that clinicians consider economic disparities when developing their treatment plans and think creatively to help people of lower socioeconomic status access nonpharmacological pain treatments, such as through telepsychology or group interventions with rolling admission. Patients with fibromyalgia may need a more thorough assessment of depression compared with those with other chronic pain conditions.

To help reduce the duration and impact of pain on the daily lives of people with neurological/neuromuscular disability, psychologists may wish to focus treatment on increasing these patients’ personal coping resources including sense of resilience, social support, pain acceptance, and sleep quality.

Woods, S.B., Priest, J.B., Kuhn, V., & Signs, T. (2019). Close relationships as a contributor to chronic pain pathogenesis: Predicting pain etiology and persistence. Social Science & Medicine, 237, Article ID 112452. http://dx.doi.org/10.1016/j.socscimed.2019.112452

Given the challenges associated with treating chronic pain, Woods and others sought to examine factors that are amenable to change that either increase one’s risk of developing pain or increase the risk of pain’s persistence. Specifically, they looked at factors of close relationships (relationship strain, relationship support, social integration), depression, anxiety, and pain severity as pathways to chronic pain.

The authors analyzed data from 1,591 participants as part of a large longitudinal study surveying midlife adults (National Survey of Midlife in the United States). They found that of participants who did not report chronic pain at baseline, those experiencing greater family strain at baseline were significantly more likely to develop chronic pain 10 years later.

The same could not be said for intimate partner strain or friend strain. In fact, no other factors (social connectivity, marital status, friendship or intimate partner quality, depression, or anxiety) predicted the development of chronic pain 10 years later.

For those initially experiencing acute pain, however, having supportive family relationships was associated with a decreased risk of that pain becoming chronic over time. This finding suggests that family support may help protect against bad outcomes for acute pain conditions, such as injury or surgery, but not for ongoing pain-related conditions, such as arthritis or fibromyalgia. Patients with acute pain who experienced depressive symptoms were also more likely to maintain their pain long term.

Finally, for both those experiencing acute or chronic pain at baseline, the severity of the pain and its interference with multiple areas of their lives predicted the continuance of pain long-term.

Clinical implications

These findings reveal the potential value of targeting family relationships to help prevent the onset of chronic pain and the escalation of acute pain to chronic pain. The authors suggest clinicians consider specific family-based treatments that focus on reducing criticism, unreliability, and hostility, and instead promote warmth and understanding. For individuals with acute pain, early family involvement in treatment may prevent the pain from becoming chronic.

O’Loughlin, I., & Newton-John, T.R.O. (2019). ‘Dis-comfort eating’: An investigation into the use of food as a coping strategy for the management of chronic pain. Appetite, 140, 288–297. http://dx.doi.org/10.1016/j.appet.2019.05.027

Obesity can exacerbate the negative effects of chronic pain, leading to increased pain intensity, pain-related disability, and comorbidities (Allen et al, 2016; Fannuele et al., 2002; Marcus, 2004; Okifuji & Hare, 2015; Wright et al., 2010). Decreased physical activity is the most commonly explored factor for why pain is associated with obesity, but it only accounts for a modest amount of variance in weight gain (Jebb & Moore, 1999).

In this study, the authors explore comfort eating as a coping mechanism and possible explanation for the association between pain and obesity.

The researchers asked 151 adults with chronic pain to complete an online survey with demographic questions as well as measures to assess stress, pain, and pain-related eating behaviors. On average, participants had been experiencing pain for 10 years, and 28% of them were unemployed due to their chronic pain.

More than 75% of participants across the Body Mass Index (BMI) spectrum reported engaging in comfort eating in response to chronic pain. While pain intensity did not directly predict their comfort eating, there was evidence to support an indirect relationship between chronic pain intensity and pain-induced comfort eating through stress—in other words, it was the stress associated with pain, rather than the pain itself, that appears to have driven the participants to seek food for comfort.

The researchers also found that those who engaged in more pain-induced comfort eating had higher BMIs, and higher BMIs, in turn, predicted a greater negative impact of pain on patient’s daily lives.

Clinical implications

This research demonstrates that pain-induced comfort eating is a common and harmful experience for people with chronic pain, regardless of their BMI. To help patients replace this pain-coping behavior, psychologists may wish to focus treatment on mindful eating, limiting triggers and cues to pain-induced comfort eating, and teaching more helpful and adaptive stress management strategies.