Nonpharmacologic Treatment of Chronic Pain—A Critical Domains Approach

From the Department of Anesthesiology, University of Michigan, Ann Arbor, MI.

Abstract

• Objective: To provide an overview of the critical treatment domains for patients with chronic pain and describe nonpharmacologic strategies by which these domains can be addressed.
• Methods: A literature review was conducted to evaluate the evidence underlying commonly used nonpharmacologic strategies for the treatment of chronic pain, with a focus on interventions that require patient engagement.
• Results: Nonpharmacologic interventions that actively engage the patient in pain management, such as exercise, behavioral activation, sleep hygiene, and stress management, are relatively easy to implement and do not necessarily require the expertise of mental health professionals. Nonpharmacologic strategies can directly address pain and also address secondary complications, and thus serve to enhance treatment outcomes.
• Conclusion: The critical domains approach can be used to organize a comprehensive nonpharmacologic approach to treating widespread chronic pain.

 According to the Institute of Medicine (IOM), chronic pain affects more Americans than coronary heart disease, diabetes, and cancer combined at an estimated cost of $635 billion per year [1]. While it has been demonstrated that we have reasonably good ability to reduce acute pain, providing pharmacologic treatment with even modest effects when addressing chronic pain remains challenging [1]. The ability to treat one form of pain successfully but not the other stems from the fact that chronic pain is not a simple extension of acute pain [2,3]; rather, the mechanisms differ and so must the treatments. The IOM report called for a cultural transformation in how pain is understood, assessed, and treated. In response, the National Pain Strategy [4] was developed. It was recommended that efficacious self-management strategies be used for individuals with chronic pain; such strategies are largely nonpharmacologic [4].

This article presents an approach to addressing chronic pain using nonpharmacologic strategies. While a number of nonpharmacologic treatments involve patients as passive recipients (eg, massage, acupuncture, balneotherapy or spa treatments), most require the patient to be engaged, eg, to exert physical energy, learn a new skill, and/or change a behavior. The approach presented here is organized around addressing critical domains, including the need to increase activity, deal with psychiatric comorbidities, address sleep problems, and tackle stress. The strategies suggested will be those that have the best evidence base and are predominantly ones that can be deployed by physicians and other health care professionals who do not necessarily have specialized training in behavioral health. A case is presented to illustrate this approach.

Case Presentation

Lisa is a 42-year-old Caucasian woman with a 2-year history of chronic low back pain presenting to a primary care clinic. She reported that the back pain began when she was working as an office manager in a busy dental clinic. The onset was sudden, occurring when she lifted a heavy box of copier paper using a “leaning and twisting motion.” The pain is described as constant (rated as 5 out of 10) and she experiences periods of more intense pain or “flares” (rated as 9 out of 10); Lisa noted that “10 is reserved for childbirth.” The flares seem to coincide with periods of stress and can result in up to 2 days of immobility, causing her to miss work at the dental office.

The pain is described as deep, aching, and throbbing but does not radiate to her legs. It is made worse by sitting still for longer than an hour and gets better if she keeps moving and gets a good night of sleep. Her sleep is generally disturbed as she has trouble falling asleep and when she does sleep, she usually wakes up feeling unrefreshed and extremely irritable. Moreover, while she knows that activity makes her pain better, Lisa can rarely find the energy or motivation to exercise.

Various evaluations by specialists have been obtained and studies conducted, including a recent MRI. All were found to be negative for a clear-cut pathology. A visit to a rheumatologist 5 years ago resulted in a diagnosis of fibromyalgia that Lisa does not accept. Upon probing, she detailed what turns out to be an almost 20-year history of chronic pain. The back pain is only the latest diagnosis in an extensive list of painful conditions including premenstrual syndrome (PMS), headache, temporomandibular joint disorder (TMJ), and fibromyalgia. There are no aspects of her history or presentation that suggest a diagnosis other than chronic musculoskeletal pain.

Lisa is a divorced mother of 2 adolescent children who are generally well-adjusted if not age-appropriately defiant. She is overweight (body mass index = 29) and admits to overeating when under stress. She says that the back pain has disrupted every aspect of her life and work is the only thing that gets adequate attention. Her salary is critical to her family’s financial stability, thus it is a priority. Lisa noted that she saves all of her energy for her job and has “nothing left in the tank” for her children or herself. She notes that, “I have zero joy in my life—I rarely go anywhere fun with my kids anymore, putter in my garden, and forget about going on dates. I can’t remember the last enjoyable thing I did!”

• What are aspects to consider in addressing this patient’s symptoms?

Lisa’s case is likely recognizable—she presents with a long history of pain in multiple areas of her body (eg, low back pain, PMS, headache, TMJ) without clear-cut pathology. She has multiple physical and social problems and limited resources. The diagnosis of fibromyalgia is likely correct. The low back pain is probably another manifestation of a broader “centralized pain” condition [5,6]. The term centralized pain refers to the amplification of pain via changes in the central nervous system [7,8]. This does not mean that peripheral nociceptive input (ie, tissue damage or inflammation) plays no role in the pain; however, it implies that any painful stimulus is experienced with greater intensity than would be expected [5,6]. Further, psychological, behavioral, and social elements tend to be key factors in centralized pain states due in part to the exhausting challenge of living with chronic pain, as well as genetic factors that predispose to both pain and mood disturbances [9].

Due to the often complex nature of chronic pain, successful treatment usually requires addressing multiple areas of concern, including addressing behavioral, cognitive, and affective processes. It is suggested that a plan for nonpharmacologic pain management could be built around 6 domains represented by the acronym ExPRESS [10], namely Exercise, Psychological distress, Regaining function, Emotional well-being, Sleep hygiene, and Stress management. This article provides a review of the literature that focuses on systematic reviews and meta-analyses to summarize a massive literature largely supporting the use of nonpharmacologic strategies such as exercise, cognitive-behavioral therapy, mindfulness-based treatments, behavioral self-management, resilience-based interventions, and education to address the ExPRESS [10] domains using Lisa’s case as an example.

• How effective is exercise for treating chronic pain and how should it be integrated into treatment?

Exercise

Over the last 5 years, a number of meta-analyses have been conducted to evaluate a robust literature regarding exercise interventions for the treatment of chronic pain [11–14]. The evidence is strong that patients with chronic pain benefit from increased physical activity and in many cases the effect size is quite substantial [14]. Meta-analytic data suggest that aerobic exercise results in significantly less pain and disability [13], improved physical fitness [14], less fatigue and better mood [14]. Exercise can be land-based or water-based [14], be conducted at a slight to moderate intensity and/or even involve only a program of walking [12]. Most established guidelines highlight the benefits of including exercise as part of the nonpharmacologic management of patients with chronic pain [15–18].

Data suggest that chronic pain patients should begin exercise training slowly starting at levels below capacity and increase duration and intensity over time until patients are exercising at low to moderate intensity (ie, 50% to 70% of age-adjusted maximum heart rate) for 20 to 30 minutes per session 2 to 3 times per week [19].

Obesity and deconditioning are common and are thought to contribute to pain sensitivity, poor sleep, and depressed mood [20]. Lisa is overweight and inactive. She injured her back and reports generally avoiding any form of exercise. Getting her moving will be imperative as an increase in physical activity could not only help her to lose weight, but could have the added benefits of decreasing her pain and stiffness, helping her sleep better and improving her mood and self-esteem. Yet, she reports not having the time or motivation.

A reasonable approach would be to not prescribe formal exercise at first but rather encourage small and immediate changes in how she already goes about her day. One concrete step would be to encourage her to stand up and stretch every 20 minutes or so while working at her computer. This is something that she cites as directly contributing to her pain. Next, an increase in physical activity such as adding a few steps every day and doing regular activities with more vigor would be a great initial step.

One of the most formidable barriers to getting patients to exercise is the perception that they must go to the gym and begin a formal program in order to achieve any benefit. As an employed single mother with two children Lisa likely lacks the time and resources for a formal exercise program. She could instead, begin a walking program that starts with reasonable goals (eg, 6000 steps per day) and builds at a slow and steady pace (eg, add 100 steps per day). Activity trackers range in price, but a simple pedometer can be found for under $10. By initiating such a walking program, the things she does already such as chores around the house all count as physical activity. She could do these with more energy and mindfulness and incrementally add activity over time.

Once a new habit of increased physical activity has been established, the strategy of branching out into new physical activities (or even more formal exercise) is usually more successful especially if they are enjoyable and feasible (ie, affordable, not too time consuming). The need to engage in more physical activity could be the impetus to encourage Lisa to do more activities with her children—walking to the park, flying a kite, and exploring the science museum are all activities that can provide physical, emotional and social benefits simultaneously.

• What interventions are helpful in addressing psychiatric comorbidity?

Psychological Distress

Comorbidity with mood and anxiety disorders is often observed and complicates treatment in patients with chronic pain states [21–23]. Patients with centralized pain conditions like fibromyalgia tend to have even higher rates of psychiatric comorbidity than those with other pain conditions like arthritis alone [24–26]. While estimates vary widely, we have recently reported that 36.2% of patients evaluated in our tertiary care setting meet case criteria for depression [27]. Such psychiatric comorbidity has been shown to be associated with increased pain, worse functioning, higher costs and increased use of opioids [27–30]. Further, suicidal ideation is common in chronic pain populations, especially those with depression and anxiety, and should be carefully evaluated if suspected [31]. The presence of psychiatric comorbidity takes a toll on the individual and society. One study found that pain patients with comorbid depression utilized twice the resources that other patients without depression utilized [32]. Perhaps the most troubling element is that psychiatric comorbidity is too often not adequately addressed in medical settings [33].

Assessing for depression using a standardized measure like the PHQ-9 [34] or anxiety using the GAD-7 [35] can provide a sense of the severity of the psychiatric symptoms. More severe forms of depression and anxiety may require referral, but more mild depressive and/or anxiety symptoms may be treated by the medical personnel the patient already knows and trusts. Nonpharmacologic strategies that can be used to address depression, anxiety, and even pain in chronic pain populations include cognitive-behavioral therapy, exercise/physical activity, regulating sleep and behavioral activation (ie, getting patients engaged with valued activities, social support).

Perhaps the most effective strategy to address depression, anxiety, and pain in chronic pain populations is cognitive-behavioral therapy (CBT) [36–38]. CBT for pain consists of both cognitive and behavioral therapy interventions. Cognitive therapy proposes that modifying maladaptive thoughts will result in changes in emotions and behavior [39]. Thus, errors in thinking like catastrophizing, overgeneralizing, and minimizing positives are confronted and changed to more realistic and helpful thoughts. This results in less emotional distress and fewer self-defeating behaviors. In cognitive therapy for chronic pain, catastrophic thoughts such as “My pain is terrible and nothing I do helps” are replaced by more adaptive thoughts like “Although my pain is severe, there still are a few things I can do to make it a little better.” Several behavioral techniques are also employed such as behavioral activation (getting patients moving again), activity pacing (not overdoing it on days patients feel good and remaining active on days they feel bad), sleep hygiene (identifying then changing behaviors know to disrupt sleep), and relaxation skills (eg, breathing, imagery, progressive muscle relaxation). Meta-analyses have shown that CBT has empirical support for its effectiveness in treating patients with chronic pain [40,41].

During the visit, Lisa reported a loss of joy in her life and then began crying. Such a report should prompt a more formal exploration of the potential for depression. She would likely benefit from antidepressant medication and behavioral intervention. The physical activity prescribed above will also pertain to treating her depressive symptoms as will strategies to improve her emotional well-being, sleep and stress noted below. Perhaps the most beneficial strategy would be to refer her to CBT for pain and depressive symptoms. CBT for pain would help Lisa acquire the skills required to address many ExPRESS [10] domains including increasing physical activity, improving mood, decreasing stress, and improving sleep.