Reprocessing therapy may reduce chronic back pain

Changing patients’ pain-related beliefs via psychological treatment appeared to offer them durable relief for chronic back pain, according to results of a randomized clinical trial published in JAMA Psychiatry.

“Leading psychological interventions for pain typically present the causes of pain as multifaceted and aim primarily to improve functioning and secondarily to reduce pain,” Yoni K. Ashar, PhD, of the department of psychiatry at Weill Cornell Medical College in New York, and colleagues wrote. “[Pain reprocessing therapy (PRT)] emphasizes that the brain actively constructs primary chronic pain in the absence of tissue damage and that reappraising the causes and threat value of pain can reduce or eliminate it.”

The researchers sought to determine whether PRT could alter patients’ beliefs surrounding the causes and threat value of pain and thus offer significant and lasting relief from primary chronic back pain. The trial took place in a university research setting between November 2017 and August 2018 and incorporated longitudinal functional MRI and 1-year follow-up assessment.

Ashar and colleagues compared PRT with an open-label placebo treatment and with usual care among a community sample. Participants randomly assigned to PRT (n = 50) completed one telehealth session with a physician and eight psychological treatment sessions over 4 weeks. Treatment incorporated cognitive, somatic and exposure-based techniques, with the aim of helping patients see their pain as related to non-dangerous brain activity instead of peripheral tissue injury.

Participants randomly assigned to placebo (n = 51) received an open-label subcutaneous saline injection in the back, and those randomly assigned to usual care (n = 50) maintained routine, ongoing care. Main outcomes and measures included 1-week mean back pain intensity score from zero to 10 after treatment, pain beliefs and functional MRI assessments of evoked pain and resting connectivity.

A total of 151 adults (mean age, 41.1 years; 54% women) reported mean pain of low to moderate severity and mean pain duration of 10 years at baseline. The researchers noted large group differences in pain at posttreatment, with a mean pain score of 1.18 among the PRT group, 2.84 among the placebo group and 3.13 among the usual care group. A total of 33 of 50 participants (66%) randomly assigned to PRT reported having no pain or almost no pain at posttreatment compared with 10 of 51 participants (20%) randomly assigned to placebo and five of 50 participants (10%) randomly assigned to usual care. At 1-year follow-up, treatment effects continued, with a mean pain score of 1.51 among the PRT group, 2.79 among the placebo group and 3 among the usual care group.

Compared with placebo, PRT appeared linked to reduced responses to evoked back pain in the anterior midcingulate and the anterior prefrontal cortex based on longitudinal fMRI. It also showed other positive neural outcomes compared with usual care and both control groups.

“Our findings raise key possibilities about the nature and treatment of primary [chronic back pain],” Ashar and colleagues wrote. “Changing fear- and avoidance-inducing beliefs about the causes and threat value of pain may provide substantial, durable pain relief for people with primary [chronic back pain].”