Human Studies

Chronic pain is a prevalent and burdensome condition. Reboot Online was developed to address treatment barriers traditionally associated with accessing face-to-face chronic pain management programs. It is a comprehensive multidisciplinary online treatment program, based on an existing and effective face-to-face multidisciplinary pain program (the Reboot program).

Anticipation of a painful experience can influence brain activity and increase sensitivity to experimental somatosensory stimuli in healthy adults, but this response is poorly understood among individuals with chronic musculoskeletal pain (CMP). Studies of brain and perceptual responses to somatosensory stimuli are used to make inferences about central nervous system dysfunction as a potential mechanism of symptoms. As such, we sought to (a) determine the influence of pain anticipation on pain-relevant brain regions and pain perception, and (b) characterize potential differences in these responses between Gulf War Veterans with CMP and matched healthy control (CO) Veterans. CMP (N = 30) and CO Veterans (N = 31) were randomized to conditions designed to generate expectations that either painful (pain) or nonpainful (no pain) stimuli would be administered. Brain responses to five nonpainful thermal stimuli were measured during fMRI, and each stimulus was rated for pain intensity and unpleasantness. In the pain condition, an incremental linear decrease in activity across stimuli was observed in the posterior cingulate cortex, cingulate cortex, and middle temporal gyrus. Further, in the pain condition, differential responses were observed between CMP and CO Veterans in the middle temporal gyrus. These findings indicate that brain responses to nonpainful thermal stimuli in Veterans with CMP are sensitive to pain anticipation, and we recommend accounting for the influence of pain anticipation in future investigations of central nervous system dysfunction in CMP.

Chronic back pain is a major global health problem, while its treatment is hampered by a lack of efficacy and restricted safety profile of common front-line therapies. The present trial aims to determine whether a 3-week open-label placebo treatment reduces pain intensity, and subjective and objective functional disability in chronic back pain patients. This randomized controlled trial, following a pretest-posttest design, enrolled 127 chronic back pain patients (pain duration > 12 weeks) from the Back Pain Center, Neurology, University Hospital Essen, Germany. Patients randomized to the open-label placebo group received a 3-week open-label placebo treatment. Patients in the treatment as usual group received no intervention. Both groups continued treatment as usual. Primary outcome was the change in pain intensity. Secondary outcomes included patient-reported functional disability, objective measures of spine mobility and depression, anxiety and stress. 122 chronic back pain patients were randomized to the open-label placebo group (N=63) or treatment as usual group (N=59). Open-label placebo application led to a larger reduction of pain intensity (-0.62±0.23 vs. 0.11±0.17, all M ± SE, p=.001, d=-0.44) as well as patient-reported functional disability (3.21±1.59 vs. 0.65±1.15, p=.020, d=-0.45) and depression scores (-1.07±0.55 vs. 0.37±0.39, p=.010, d=-0.50) compared to treatment as usual only. OLP treatment did not affect objective mobility parameters, anxiety and stress. Our study demonstrates that a 3-week open-label placebo treatment is safe, well tolerated and reduces pain, disability and depressive symptoms in chronic back pain. Trial registration: German Clinical Trials Register, DRKS00012712.