The Effects of Mindfulness Based Stress Reduction on Brain Gray Matter Volume and Psychosocial Co-Morbidities in Episodic Migraine Patients

Abstract

Background: Studies show that migraine patients have altered brain structure. The morbidity associated with migraine is due to both the headaches and comorbid psychosocial factors, such as anxiety and depression. Current pharmacological therapies either prevent headaches or treat the ongoing pain, but fail to address the comprehensive migraine experience. Objectives: The comprehensive effects of Mindfulness Based Stress Reduction (MBSR) in episodic migraine patients enrolled in the MRI Outcomes of Mindfulness Meditation for Migraine Clinical Trial were assessed. We examined longitudinal changes in brain grey matter volume (GMV) of patients and healthy controls (HC), changes in psychosocial well-being and the manner in which these psychosocial factors were associated with treatment response (50% reduction in headache frequency post-intervention). Methods: Patients were randomized to receive MBSR or stress management for headache (SMH). Patients were scanned at three time points approximately 3 months apart (baseline, mid-intervention and post-intervention), completing psychosocial questionnaires and headache diaries. HC were also enrolled and completed the same MRI sessions and questionnaires. Results: From baseline to six months HC had reductions in six regions: bilateral superior frontal gyrus (SFG), anterior cingulate cortex, right middle frontal gyrus and anterior insula. Compared to HC, patients had increased GMV from baseline to six months in the right SFG and in a cluster located in the left parietal cortex. At baseline patients without prior clinical care for migraine had reduced GMV in the right dorsal medial prefrontal cortex compared to those with prior care. There was no difference between MBSR and SMH in psychosocial and quality of life measures (stress, anxiety, depression or sleep) from baseline to six months. Sleep quality improved significantly in both patient groups at 6 months. Baseline stress, depression and anxiety scores were not associated with treatment response. Mediation analysis showed that small significant changes in psychosocial scores over time were responsible for 6-8% of the proportion of the treatment response. Conclusion: Migraine patients had increased GMV compared to controls. These changes are likely linked to treatment effects. While there were no significant longitudinal psychosocial changes, small improvements were important in mediating the effect of the treatment on headache frequency.