Cognitive Therapy, Mindfulness-based Stress Reduction, and Behavior Therapy for the Treatment of Chronic Pain

Randomized Controlled Trial

John W. Burns; Mark P. Jensen; Beverly Thorn; Teresa A. Lillis; James Carmody; Andrea K. Newman; Francis Keefe

Disclosures

Pain. 2022;163(2):376-389. 

In This Article

Results

Sample Description

As presented in Table 1, slightly more than half of the participants were Black/African American (51%), women (58%), and had an average age of 52.9 years (SD = 12.2). Over a third of the sample had at least a college education (38%) and were married (38%). Chronic pain duration was 11.7 years on average (SD = 11.0). Treatment groups did not differ significantly on any demographic or pain-related variable. Means and SDs of all outcome variables at baseline are shown in Table 2. There were no significant differences between treatment conditions on these variables.

Linear Mixed Model Treatment Effects on Outcomes Across Eight Sessions

Figures 2–6 display the marginal means and standard errors computed by the linear mixed models for values at baseline, all 8 sessions, and six-month follow-up for the CT, BT, MBSR, and TAU groups.

Figure 2.

Marginal means and standard errors from linear mixed models for pain interference. BT, behavioral therapy; CT, cognitive therapy; MBSR, mindfulness-based stress reduction; TAU, treatment as usual.

Figure 3.

Marginal means and standard errors from linear mixed models for pain intensity. BT, behavioral therapy; CT, cognitive therapy; MBSR, mindfulness-based stress reduction; TAU, treatment as usual.

Figure 4.

Marginal means and standard errors from linear mixed models for depressive symptoms. BT, behavioral therapy; CT, cognitive therapy; MBSR, mindfulness-based stress reduction; TAU, treatment as usual.

Figure 5.

Marginal means and standard errors from linear mixed models for physical function. BT, behavioral therapy; CT, cognitive therapy; MBSR, mindfulness-based stress reduction; TAU, treatment as usual.

Figure 6.

Marginal means and standard errors from linear mixed models for sleep disturbance. BT, behavioral therapy; CT, cognitive therapy; MBSR, mindfulness-based stress reduction; TAU, treatment as usual.

Pain Interference. A significant Group × Time interaction was observed for Pain Interference Scale scores (F[3,1863.73] = 4.61 P < 0.05). Pairwise comparison analyses revealed no significant Group × Time interactions among treatment groups for Pain Interference Scale scores (range B = [−0.01] to [−0.02]), indicating that the 3 active treatments had similar effects on pain interference changes. Significant Group × Time interactions were observed when each treatment group was compared with TAU (Table 3). Although all 4 groups showed significant reductions in Pain Interference over time, the BT, CT, and MBSR groups showed larger reductions when compared with the TAU group. The region of significance calculated for each interaction indicated that Pain Interference scores from MBSR participants differed significantly from TAU participants beginning at session 7, BT participants did not differ significantly from TAU until session 8, and CT participants did not differ significantly from TAU participants until session 8 (d = 0.26). Effect sizes comparing TAU values at session 8 with the other groups ranged from Cohen's d = 0.25 to d = 0.26.

Pain Intensity. A significant overall Group × Time interaction was observed for Pain Intensity ratings (F[3,1648.08] = 11.63 P < 0.05). Pairwise comparison analyses revealed no significant Group × Time interactions among the 3 active treatment groups (range B = −0.01 to −0.03), indicating that the active treatments had similar effects on pain intensity changes. Significant Group × Time interactions were observed when each treatment group was compared with TAU. As shown in Table 3, all 4 groups showed significant reduction in Pain Intensity ratings over the 8 sessions. However, the BT, CT, and MBSR groups showed larger reductions in Pain Intensity ratings when compared with the TAU group. The region of significance calculated for each interaction indicated that Pain Intensity ratings from BT participants differed significantly from TAU participants beginning at session 5, that CT participants differed significantly from TAU beginning at session 6, and that MBSR participants differed significantly from TAU participants beginning at session 6. Effect sizes comparing TAU at session 8 to the other groups ranged from Cohen's d = 0.30 to d = 0.48.

Physical Function. A significant overall Group × Time interaction was found for the Physical Function Scale scores (F[3,1708.83] = 3.61 P < 0.05). In pairwise comparison analyses, no significant Group × Time interactions were observed among the 3 active treatment groups (range B = 0.03–0.04), indicating, again, that the 3 treatments showed similar effects on physical function. Significant interactions were observed when each treatment group was compared with TAU. As shown in Table 3, the TAU group did not show a significant change in Physical Function Scale scores across the study, but the BT, CT, and MBSR groups' Physical Function scores did increase significantly over time. The region of significance calculated for each interaction indicated that Physical Function scores from MBSR participants began to differ significantly from TAU participants at session 4 (d = −0.21), that BT participants differed significantly from TAU participants beginning at session 7 (d = −0.26), and that CT participants differed significantly from TAU participants beginning at session 8 (d = −0.23). Effect sizes comparing TAU at session 8 with the other groups ranged from Cohen's d = −0.21 to d = −0.26.

Depressive Symptoms. A significant overall Group × Time interaction was observed for Depressive Symptom scores (F[3,1683.64] = 10.41, P < 0.05). Pairwise comparison analyses again revealed no significant Group × Time interactions among the 3 active treatment groups (range B = [−0.01] to [−0.11]). Significant interactions were observed when each treatment group was compared with TAU. As shown in Table 3, TAU participants did not show significant changes in Depressive Symptom scores across the 8 sessions, whereas Depressive Symptom scores for the BT, CT, and MBSR groups decreased significantly over the course of treatment. The region of significance calculated for each interaction indicated that Depression scores from BT participants began to differ significantly from TAU participants at session 4 (d = 0.53), that CT participants' Depression scores differed significantly from TAU participants' beginning at session 7 (d = 0.43), and that MBSR participants' Depression scores differed significantly from TAU participants beginning at session 8 (d = 0.26). Effect sizes comparing TAU at session 8 with the other groups ranged from Cohen's d = 0.26 to d = 0.53.

Sleep Disturbance. Finally, a significant overall Group × Time interaction was observed for Sleep Disturbance scores (F[3,1730.09] = 5.59 P < 0.05). Pairwise comparison analyses showed no significant Group × Time interactions among 3 active treatment groups (range B = [−0.01] to [−0.06]), but, again, significant interactions were observed when each treatment group was compared with TAU. As shown in Table 3, all 4 groups demonstrated significant reductions in Sleep Disturbance over the course of treatment. However, BT, CT, and MBSR groups showed larger reductions in Sleep Disturbance scores at posttreatment than the TAU group. The region of significance calculated for each interaction indicated that Sleep Disturbance scores from BT participants began to differ significantly from TAU participants after session 1, that CT participants' Sleep Disturbance scores differed significantly from TAU participants' beginning at session 3, and that MBSR participants' Sleep Disturbance scores differed significantly from TAU participants beginning at session 2. Effect sizes comparing TAU at session 8 with the other groups ranged from Cohen's d = 0.26 to d = 0.61.

Treatment Effects on Outcomes From Posttreatment to 6-month Follow-up

There were no significant between-group interactions for posttreatment to six-month follow-up on Pain Interference, Pain Intensity, Physical Function, Depression, or Sleep Disturbance. Within-group analyses showed that the MBSR group's Pain Interference ratings significantly increased from post-treatment to six-month follow-up (mean difference = −0.27, SE = 0.12, 95% C.I. [−0.51 to −0.03], P < 0.05). The other groups did not have a significant difference in marginal means between posttreatment and six-month follow-up for any other outcome variable. The nonsignificant Group × Time interactions for the posttreatment to six-month follow-up epoch coupled with the mostly nonsignificant effects of time for the individual groups strongly suggested that the 3 active treatment groups preserved their pretreatment to posttreatment gains.

Treatment Effects on Outcomes From Baseline to 6-month Follow-up

Similar to the baseline to session 8 analyses, significant Group × Time interactions were observed for Pain Interference Scale scores (F[3,2104.47] = 4.48 P < 0.05), Pain Intensity ratings (F[3,1886.97] = 11.14 P < 0.05), Physical Function Scale scores (F[3,1934.04] = 45.08 P < 0.05), Depressive Symptom scores [F(3,1815.28) = 10.10, P < 0.05], and Sleep Disturbance scores (F[3,1822.27] = 6.92 P < 0.05). See Table 4. Pairwise comparison analyses for all outcome factors revealed no significant Group × Time interactions among treatment groups. Significant Group × Time interactions for each outcome factor were observed when each treatment group was compared with TAU, however. Effect sizes comparing TAU values at 6-month follow-up with the other groups ranged from Cohen's d = −0.18 to d = 0.56, which were slightly attenuated from the effect sizes observed for baseline to session 8 comparisons.

Clinically Meaningful Changes in Pain Intensity

Clinically meaningful improvement in pain intensity was assessed. Clinically meaningful change was defined as a 30% or greater reduction in pain intensity from pretreatment to posttreatment. We used a modified ITT approach in which we included in these responder analyses any participant who completed at least one treatment session, or for TAU participants, who completed at least one weekly assessment. The rationale for using a modified ITT approach was to include only participants who actually participated in study procedures and who were therefore exposed to some level of dose of treatment and/or an assessment session. The frequencies were as follows: TAU = 17.1%, BT = 33.3%, CT = 28.7%, and MBSR = 24.5%. Statistically significant between-group differences were found, such that BT and CT had a significantly larger proportion of participants with 30% or greater improvement on pain intensity than TAU participants (χ 2 [3,429] = 9.42; P < 0.03). Mindfulness-based stress reduction did not differ significantly from TAU.

Clinically meaningful worsening of pain intensity was also assessed following recommendations of Palermo et al.[34] Clinically meaningful worsening was defined as a 30% or greater increase in pain intensity from pretreatment to post-treatment.[17] The frequencies were: TAU = 10.1%, BT = 5.8%, CT = 9.3%, and MBSR = 7.0%. Between-group differences in these increases were nonsignificant (χ 2 [3,429] = 0.41, P > 0.05].

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