Effects of hypnosis, cognitive therapy, hypnotic cognitive therapy, and pain education in adults with chronic pain: a randomized clinical trial

Chronic pain is a significant health problem worldwide with limited pharmacological treatment options. This study evaluated the relative efficacy of 4 treatment sessions each of 4 nonpharmacological treatments: (1) hypnotic cognitive therapy (using hypnosis to alter the meaning of pain); (2) standard cognitive therapy; (3) hypnosis focused on pain reduction, and (4) pain education. One hundred seventy-three individuals with chronic pain were randomly assigned to receive 4 sessions of 1 of the 4 treatments. Primary (pain intensity) and secondary outcome measures were administered by assessors unaware of treatment allocation at pretreatment, posttreatment, and 3-, 6-, and 12-month follow-up. Treatment effects were evaluated using analysis of variance, a generalized estimating equation approach, or a Fisher exact test, depending on the outcome domain examined. All 4 treatments were associated with medium to large effect size improvements in pain intensity that maintained up to 12 months posttreatment. Pretreatment to posttreatment improvements were observed across the 4 treatment conditions on the secondary outcomes of pain interference and depressive symptoms, with some return towards pretreatment levels at 12-month follow-up. No significant between-group differences emerged in omnibus analyses, and few statistically significant between-group differences emerged in the planned pairwise analyses, although the 2 significant effects that did emerge favored hypnotic cognitive therapy. Future research is needed to determine whether the significant differences that emerged are reliable.