Enhanced mindfulness-based stress reduction in episodic migraine-effects on sleep quality, anxiety, stress, and depression: a secondary analysis of a randomized clinical trial

Abstract

Patients with migraine suffer from high morbidity related to the repeated headache attacks, characteristic of the disorder, poor sleep, and a high prevalence of comorbid psychosocial disorders. Current pharmacological therapies do not address these aspects of migraine, but nonpharmacological treatments such as mindfulness-based stress reduction (MBSR) have been shown to improve both pain and psychological well-being. In this secondary analysis, we examined the change over time in sleep quality and psychosocial outcomes from the magnetic resonance imaging outcomes for mindfulness meditation clinical trial and assessed how these mediated treatment response (50% reduction in headache frequency postintervention). We also examined the relationship between baseline values and treatment response. The trial (primary outcomes previously reported) included 98 patients with episodic migraine randomized to either enhanced MBSR (MBSR+) or stress management for headache. They completed psychosocial questionnaires and headache diaries at baseline (preintervention), midintervention (10 weeks after baseline), and postintervention (20 weeks after baseline). There was a significant improvement in sleep quality from baseline to postintervention (P = 0.0025) in both groups. There were no significant changes from baseline or between groups in anxiety, depression, and stress. There was also no significant association between baseline scores and treatment response. Mediation analysis showed a significant indirect effect of 6% for sleep: In other words, small improvements in sleep may have contributed to the efficacy of MBSR+.Trial registration: NCT02133209.

Figure 1:. Flow diagram to illustrate the ordering of study activities

Blue rectangles represent the time periods in the study from pre-baseline when patients were enrolled to post-intervention when patients had completed the last intervention session. Boxes outlined in blue at the bottom highlight activities that take place at the MRI visits at each time point. Boxes with a green outline detail activities that take place between each MRI session. All participants completed headache diaries prior to randomization and the commencement of intervention. Headache diaries were collected over a 28-day period prior to randomization. After the initial 8 weeks of intervention, participants competed their second 28 day headache diary. After the completion of the second 8 weeks of intervention, participants completed their post-intervention 28 day headache diary. All participants completed an MRI visit and the associated questionnaires at baseline prior to the randomization and intervention. The second MRI visit was conducted after the initial 8 weeks of intervention and the third was conducted after the second 8 weeks of intervention.

Figure 2:. Causal diagram to represent plausible mediation relationship between MBSR+ and treatment response

Arrows assume direction of causal relationships. Model assumes no unmeasured confounding. Black boxes indicate baseline covariates. Solid black arrows represent adjusted confounding. The orange box indicates the randomized treatment MBSR+ vs. SMH. The solid green box is the outcome which is treatment response. This variable is created from baseline and post-intervention headache frequency (green outlined boxes) Blue boxes represent possible mediators of the relationship between exposure and outcome. Baseline covariates were measured prior to randomization and therefore are not affected by the treatment. Mid-point (10 weeks post baseline) sleep quality, anxiety, depression and stress were measured at the scan visit directly after the completion of the first block of treatment. Headache diaries were completed for 28 days post the first block of treatment and therefore are captured after the psychosocial measurements. Post-treatment (20 weeks post baseline) psychosocial measurements were taken at the scan visit directly after the final treatment block had been completed. These visits usually occur over a two-week period post study completion. Headache diaries are completed for 28 days post treatment.