Biomarker Response to Mindfulness Intervention in Veterans Diagnosed with Post-traumatic Stress Disorder.

In veterans with PTSD, mindfulness-based stress reduction (MBSR) and present-centered group therapy both increased morning cortisol levels from baseline to 9 weeks, but the increase was significantly smaller with MBSR (mean difference 1.69 ± 0.8 SE). Changes in interleukin-6 and C-reactive protein did not differ between groups. Greater self-reported mindfulness was linked to higher cortisol and to reduced PTSD and depression severity. Higher IL-6 and CRP were associated with less severe PTSD but not depression. Pooled results confirmed MBSR outperformed the active control for clinical improvement. Increased mindfulness may recalibrate cortisol levels, suggesting a therapeutic response.

Study at a glance

Abstract

This study evaluates the effects of treatment with mindfulness-based stress reduction (MBSR) compared to the active control, present-centered group therapy (PCGT), on morning plasma cortisol, interleukin-6 (IL-6), and C-reactive protein (CRP) in veterans diagnosed with post-traumatic stress disorder (PTSD). In a post hoc exploratory analysis, we pooled biomarkers and clinical outcomes of mindfulness, PTSD, and depression from two randomized controlled trials comparing MBSR (n = 104) to PCGT (n = 106) in U.S. military veterans diagnosed with PTSD. Linear mixed-effects modeling was used to evaluate associations between changes in biomarkers and clinical outcomes from baseline to 9-week primary endpoint and 16-week follow-up endpoint. Cortisol levels were inversely related to self-reported PTSD symptoms at baseline (p = 0.02). Cortisol increased from baseline to 9-week endpoint for both groups, but significantly less so in the MBSR group compared to PCGT group (mean difference 1.69 ± 0.8 SE; p = 0.035). Changes in IL-6 and CRP did not differ between groups at either baseline or week 9. From baseline to week 9, increased mindfulness was significantly associated with increased cortisol (p = 0.02) and decreased PTSD and depression severity (p < 0.01). Increased IL-6 and CRP were significantly associated with decreased PTSD severity (p < 0.05), but not depression. Pooled analysis corroborated earlier findings that MBSR is significantly better than PCGT in improving clinical outcomes. Increased mindfulness was strongly associated with improved symptoms. Increased mindfulness is associated with a recalibration of cortisol levels which may be indicative of therapeutic response, especially in patients with lower baseline cortisol. Furthermore, mindfulness-based practices improve symptoms of PTSD and depression in a significant correlation with self-reported levels of mindfulness. NCT01532999 and NCT01548742.