Can Treating Pain and Mood Together Improve Outcomes for People With Chronic Low Back Pain?

Chronic low back pain is one of the most common types of pain, affecting about 50 million adult Americans. Many of these people rely on strong pain medications, including opioids, to be able to move and perform everyday activities.

Chronic pain also influences emotional and mental well-being. About one in five people with chronic low back pain experience high levels of “negative affect,” or feelings of sadness, fear about their pain, and anxiety. Most people develop these mental health symptoms after they begin experiencing pain, especially if the pain is severe all the time and interferes with their daily activities. The presence of depression and anxiety not only worsen an individual’s overall well-being, but in turn makes it even harder to relieve pain effectively – potentially increasing the risk of opioid use and misuse.

The Helping to End Addiction Long-term^® Initiative, or NIH HEAL Initiative^®, initiated the Back Pain Consortium (BACPAC) Research Program to help reduce reliance on opioid pain medications and the associated risks for patients with chronic low back pain, by seeking to identify effective alternative treatment options that can be adapted to an individual’s needs. As part of this program, HEAL researchers led by Ajay D. Wasan, M.D., M.Sc., from the University of Pittsburgh are testing a combination of antidepressant medications and physical therapy in people with both chronic low back pain and mood disorders.

The Interaction of Pain and Mood-Related Disorders

People experiencing chronic pain and depression or anxiety tend to experience greater pain and disability than those without these conditions. They also don’t respond as well to many pain treatments – including medications, nerve blocks, physical therapy, or surgery – compared to people without depression or anxiety. As a result, they are three to four times more likely to be prescribed opioid pain medications.

Together, these factors put people with chronic pain and mood-related disorders at increased risk of opioid misuse and overdose. “In fact,” says Wasan, “negative affect is one of the main risk factors for misusing prescription opioids to cope with mood-related issues.”

Treatment Approaches for Pain and Mood-Related Disorders

To improve pain treatment and help reduce reliance on opioid medications in people with both chronic low back pain and mood-related disorders, Wasan and his team are investigating a combination of two approaches: treatment with antidepressant medications and a special type of physical therapy. Both treatments have previously been shown to improve outcomes for people experiencing chronic pain but testing them together is new.

Antidepressant therapy mainly targets a person’s mood, but it can also provide pain relief and increase the ability to function.

Fear-avoidance physical therapy (also called fear-of-movement physical therapy) is based on the observation that many people with chronic low back pain are so afraid of experiencing pain, they avoid movement as much as possible. Doing so leads to underuse of affected muscles, disability, and depression – all of which can worsen pain, setting off a vicious cycle. Fear avoidance physical therapy aims to break this cycle and focuses on getting patients active and moving. This approach also has been shown to improve both physical and mental well-being and function.

Treating Pain and Mood Together Improves Outcomes

In previous research, Wasan’s team assigned 71 patients with chronic low back pain and high negative affect to either antidepressant therapy, fear-avoidance physical therapy, a combination of both treatments, or a control condition that included education about pain management only. After 4 months of treatment, people who received the combination therapy appeared to do better with respect to both health conditions:

• About 75 to 80 percent of participants in this group showed improvements in depression and anxiety.
• About 40 percent showed improvements in both pain and function.

“You may think this outcome seems obvious, that using a combination of two or more treatments that address different aspects of a patient’s pain experience is better than relying on one approach alone,” says Wasan. However, he adds, it’s a new approach because to date very few studies have assessed the effectiveness of treatment combinations (also called multi-modal treatments) in people with chronic pain, and especially in those with coexisting mood disorders.

An Expanded Study to Determine Effectiveness

Encouraged by these initial findings, through the BACPAC program, Wasan is conducting a larger, phase 2 clinical trial to determine the effectiveness of the antidepressant/physical therapy treatment combination in a larger group of patients.

“We’re trying to improve negative affect, which in itself is important to do,” explains Wasan, “but we are also looking at whether treatment can improve patients’ pain and physical function, and in those who are prescribed opioids, if it can reduce opioid misuse.”

For this study, they are using a type of physical therapy they call enhanced fear avoidance rehabilitation – “enhanced” because they have added a mobile app that individuals can use in between their physical therapy sessions. This app includes, for example, education about pain and helpful instructional videos.

The study is recruiting 300 patients with chronic low back pain and high levels of both depression and anxiety; some of these individuals may be currently taking opioid pain medications.

The participants are randomly split into three groups that receive either antidepressant therapy only, specialized physical therapy only, or both. In the first phase of the study, the patients receive their assigned treatment for 4 months. The researchers will then compare the proportion of patients in each group who show improvements in both pain and self-reported physical function (such as their ability to walk), or who show improvements in depression symptoms. Additionally, they will determine whether treatment reduced the need for opioid medications and any potential opioid misuse.

In a second 4-month phase, participants who show a response after the first phase will continue their treatment, whereas participants who received only antidepressants or specialized physical therapy and show no improvement will be randomly reassigned to the same treatment or switched to another approach.

Patient-Centered Treatment

Through this combination strategy, the researchers are seeking to increase the overall number of patients who show a treatment response and identify factors that predict treatment outcomes.

One of the main goals of the NIH HEAL Initiative’s BACPAC program is to personalize interventions for chronic low back pain based on individual characteristics and preferences. Ultimately, BACPAC research projects aim to create a predictive tool that balances the many factors that contribute to chronic low back pain (which differ among people) and suggest a personalized treatment plan based on the specifics of that individual’s characteristics.

“We feel that this novel multimodal combination approach of medication and physical therapy can really cause a shift in current treatment strategies,” says Wasan. “We are confident that the community practice environment is poised to adopt the strategy too.”