Assessing the Effectiveness of Mindfulness in the Treatment of Chronic Back Pain: Use of Quantitative Sensory Pain Assessment

Abstract

Findings from clinical trials of mindfulness-based interventions (MBI) support significant effects on chronic pain, yet the mechanisms underlying these effects are not well understood. A limitation of current research is reliance on global measures of functioning or narrow, self-report ratings of chronic pain severity. The present research aims to explore potential mechanisms that may explain the effects of MBIs on chronic pain by focusing on acute pain ratings, using quantitative sensory pain testing (QST) rather than chronic pain ratings. Thirty-six patients (10 men, 26 women, mean age = 58.03, ± 14.9) with chronic low back pain (CLBP) were randomly assigned to an 8-week MBI or wait-list control. QST measures of thermal and pain thresholds, as well as pain ratings to fixed stimuli, self-report measures of chronic pain severity, and interference with daily activities were assessed at baseline and after 8 weeks. We found a significant group X time interactions in self-report ratings of chronic pain severity (p = .04, ηp2 = .12) and interference (p = .04, ηp2 = .11): The MBI group showed a decrease in ratings while the control group showed an increase. Also, while patients in the control group exhibited an increase in suprathreshold pain ratings over time (p = .03, ηp2 = .15), indicating an apparent sensitization effect to painful stimuli, participants in the MBI group maintained their original ratings. The results suggest that mindfulness practice may have a “buffering effect” for CLBP patients, by attenuating their tendency to facilitate pain experience.