Psychological therapy that changes an individual’s beliefs about pain not only provides lasting chronic pain relief but also alters brain regions related to pain generation, new research shows.
In the first randomized controlled test of pain-reprocessing therapy (PRT), two-thirds of patients with chronic back pain (CBP) who received 4 weeks of PRT were pain free or nearly pain free afterward – and for most patients, relief was maintained for 1 year, the researchers found.
“Primary chronic back pain can be dramatically reduced or even eliminated by psychological treatment focused on changing how threatening we perceive the pain to be,” first author Yoni Ashar, PhD, department of psychiatry, Weill Cornell Medicine, New York, said in an interview.
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given that large reductions in pain have rarely been observed in studies that tested psychological therapies for chronic back pain.The study was published online Sept. 29, 2021, in JAMA Psychiatry.
Rethinking pain
CBP is a leading cause of disability, and treatment is often ineffective. In about 85% of cases of primary CBP, a definitive cause of the pain can’t be identified. In these cases, fear, avoidance, and beliefs that pain indicates injury may contribute to ongoing CBP.
PRT educates patients about the role of the brain in generating chronic pain; helps them reappraise their pain as they engage in movements that they had been afraid to undertake; and helps them address emotions that may exacerbate pain.
The study included 151 adults (54% women; mean age, 41 years) who had primary CBP of low to moderate severity (mean pain intensity, 4 of 10) for an average of 10 years.
A total of 50 participants were randomly allocated to undergo PRT (one telehealth session with a physician and eight PRT sessions over 4 weeks), 51 to receive placebo (subcutaneous saline injection in the back), and 50 to continue their routine, usual ongoing care.
Large group differences in pain were observed after treatment. The mean pain score was 1.18 in the PRT group, 2.84 in the placebo group, and 3.13 in the usual-care group. Hedges’ g was –1.14 for PRT versus placebo and –1.74 for PRT versus usual care (P < .001).
Two-thirds (66%) of adults in the PRT group were pain free or nearly pain free following treatment (pain-intensity score of 0 or 1 out of 10), compared with 20% of those in the placebo group and 10% of those who received usual care.
Treatment effects were maintained at 1-year follow-up. The mean pain score was 1.51 in the PRT group, 2.79 in the placebo group, and 3.00 in the usual-care group. Neither age nor sex moderated the effect of PRT on pain intensity.
Retraining the brain
The researchers said the effects of PRT on pain were mediated by lessening the belief that pain indicates tissue damage. Of note, PRT also reduced experimentally evoked back pain and spontaneous pain during functional MRI, with large effect sizes.
“The idea is that by thinking about the pain as safe rather than threatening, patients can alter the brain networks reinforcing the pain, and neutralize it,” Dr. Ashar said in a news release.
The authors noted that study participants were relatively well educated and active. The participants reported having longstanding low to moderate pain and disability at baseline.
The physician and therapists were experts in delivering PRT. Future studies should test generalizability to other patient populations, therapists, and treatment contexts.
“Our clinical experience shows that PRT is effective for other primary chronic pain conditions as well,” said Dr. Ashar, including primary knee pain and tension headache.