RESUMEN
OBJECTIVE: Chronic pain is a disabling illness, often comorbid with depression. We performed a randomized controlled pilot study on mindfulness-based cognitive therapy (MBCT) targeting depression in a chronic pain population. METHOD: Participants with chronic pain lasting ≥ 3 months; DSM-IV major depressive disorder (MDD), dysthymic disorder, or depressive disorder not otherwise specified; and a 16-item Quick Inventory of Depressive Symptomatology-Clinician Rated (QIDS-C16) score ≥ 6 were randomly assigned to MBCT (n = 26) or waitlist (n = 14). We adapted the original MBCT intervention for depression relapse prevention by modifying the psychoeducation and cognitive-behavioral therapy elements to an actively depressed chronic pain population. We analyzed an intent-to-treat (ITT) and a per-protocol sample; the per-protocol sample included participants in the MBCT group who completed at least 4 of 8 sessions. Changes in scores on the QIDS-C16 and 17-item Hamilton Depression Rating Sale (HDRS17) were the primary outcome measures. Pain, quality of life, and anxiety were secondary outcome measures. Data collection took place between January 2012 and July 2013. RESULTS: Nineteen participants (73%) completed the MBCT program. No significant adverse events were reported in either treatment group. ITT analysis (n = 40) revealed no significant differences. Repeated-measures analyses of variance for the per-protocol sample (n = 33) revealed a significant treatment × time interaction (F1,31 = 4.67, P = .039, η²p = 0.13) for QIDS-C16 score, driven by a significant decrease in the MBCT group (t18 = 5.15, P < .001, d = >1.6), but not in the control group (t13 = 2.01, P = .066). The HDRS17 scores did not differ significantly between groups. The study ended before the projected sample size was obtained, which might have prevented effect detection in some outcome measures. CONCLUSIONS: MBCT shows potential as a treatment for depression in individuals with chronic pain, but larger controlled trials are needed. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01473615.