Posted 04.28.2020 | by AMRA

Migraines, marked by intense, throbbing headaches, nausea, vomiting, and sensitivity to light, affect 13% of the adult population and are the sixth most frequent cause of disability. Migraines are known to be accompanied by changes in brain structures involved with cognitive aspects of pain processing including the insula, cingulate, and prefrontal cortices. This is an area of interest because mindfulness training is thought to work, in part, by altering one’s thoughts and attitudes towards pain.

Seminowicz et al. [Pain] conducted a randomized controlled trial to test if mindfulness training reduces migraines and determine whether it alters brain structure and function in regions related to cognitive aspects of pain processing.

The researchers randomly assigned 98 migraineurs (average age = 36 years; 72% Caucasian; 91% female) who had experienced 4-14 days of headache in the past month to either enhanced Mindfulness-Based Stress Reduction (MBSR) or a stress management program. Both programs met in 2-hour weekly groups for the first 8 weeks, and biweekly for the following 8 weeks. MBSR differed from the conventional standard in its addition of four group sessions after the initial 8 weeks. These additional sessions emphasized developing qualities of self-compassion, gratitude, equanimity, and sympathetic joy, and applying mindfulness skills before, during, and after migraines.

The stress management control offered didactic content focused on understanding stress, triggers, pain, sleep hygiene, and medications along with group support and muscle stretching exercises. Attendance to all scheduled groups sessions and/or individual make-up sessions was high (86% in MBSR and 83% in the control group).

All participants completed headache questionnaires at baseline and at week 10, 20, and 52. In addition, they completed fMRI brain scans at baseline and week 10 and 20 at rest, while exposed to painful heat stimuli, and while undergoing a cognitive challenge in order to activate areas of the brain implicated in cognitive aspects of pain perception. The cognitive challenge involved observing sets of three alphanumeric characters and rapidly identifying which of the characters differed from the other two by button press.

The results showed that at week 10 (after 8 MBSR sessions), MBSR participants had significantly fewer mean headache days (5.5) than controls (6.9). At week 20 (2 weeks following intervention completion), the difference remained significant with the MBSR group having an average of 4.6 headache days per month (a decrease of 3.2 days from baseline) compared to 6.0 days for controls (a decrease of 1.7 days from baseline).

At week 20, 52% of MBSR participants had at least a 50% improvement in their headaches compared to 23% of controls. At week 20, the MBSR group reported significantly less headache-related disability. Although the MBSR group had fewer headache days per month than controls at week 52 (4.6 vs. 5.6), the group difference did not reach statistical significance.

No treatment group differences were found at any point in time for regions-of-interest in brain gray matter volume, activation during pain or cognitive tasks, or resting state connectivity. Both groups showed significantly decreased anterior mid-cingulate volume and decreased insula connectivity to the cognitive task network over time.

Whole brain analyses showed some significant between-group changes during cognitive activation reflecting decreased activation of a portion of the visual cortex and an area surrounding the insula, and changes in functional connectivity between a portion of the insula and regions in the parietal and occipital cortex. The researchers suggest these changes may reflect increased cognitive efficiency due to either meditative practice or decreased days in pain.

The study shows that a lengthened MBSR intervention reduces the number of days with a headache and headache-related disability in migraine sufferers two weeks following intervention. The observed magnitude of improvement in the short term equals that achieved by first-line prophylactic pharmaceutical interventions such as valproic acid. The beneficial effect was not sustained at one-year follow-up, suggesting a need to actively continue mindfulness practice.

MBSR did not impact unique brain activity and structure in the regions of interest related to pain perception. Participants were reportedly highly educated and motivated, and thus might not be representative of the general population with migraines. Also, the significant brain changes noted are outside the proposed region of interest, thus increasing the need to replicate these findings in future studies.

Reference:

Seminowicz, D. A., Burrowes, S. A., Kearson, A., Zhang, J., Krimmel, S. R., Samawi, L., . . . Haythornthwaite, J. A. (2020). Enhanced mindfulness based stress reduction (MBSR+) in episodic migraine: A randomized clinical trial with MRI outcomes. Pain.

[Link to study]