Cognitive behavioral therapy, mindfulness, and cortisol habituation: A randomized controlled trial.

BACKGROUND: Hypothalamic-pituitary-adrenocortical (HPA) axis dysregulation is associated with disease and may be indexed by poor cortisol habituation (i.e., a failure to show decreased responding with repeated stressor exposure). Thus, stress management training that can enhance HPA axis habituation may benefit health. To date, the effects of Mindfulness Based Stress Reduction (MBSR) and Cognitive Behavioral Therapy (CBT) interventions on HPA axis habituation remain untested. To test the effects of MBSR and CBT on HPA axis habituation, the present study used a parallel arm randomized controlled trial. METHODS: Healthy adults reporting moderate-to-high stress (n = 138) were randomly assigned to a 6-week MBSR intervention, a 6-week CBT intervention, or Waitlist control group. Post-intervention, participants completed a social-evaluative performance stressor during each of two laboratory visits scheduled 48-h apart. Salivary cortisol was collected pre-stressor, and 25, 35, and 60 min post-stressor onset during each visit. Final analyses included 86 participants who completed procedures up to the first laboratory visit. RESULTS: Relative to the control condition, both MBSR and CBT groups showed greater cortisol habituation. The MBSR group exhibited marginally greater habituation than the Waitlist group in cortisol samples corresponding to the recovery time points (35 and 60 min post-stressor onset). In contrast, the CBT group showed greater habituation than the Waitlist across all sampling timepoints collected (pre-stressor, 25, 35, and 60 min post-stressor onset). Yet, the CBT group also demonstrated elevated pre-stressor cortisol during the first visit. CONCLUSIONS: Results suggest that MBSR and CBT interventions promote greater HPA axis habituation relative to no training, but do not reduce overall cortisol output (i.e., across both visits). Observed differences between CBT and MBSR training in relation to cortisol habituation are discussed.

Relationship between omega-3 fatty acids and plasma neuroactive steroids in alcoholism, depression and controls.

Deficiency in the long-chain omega-3 fatty acid, docosahexaenoic acid (DHA) has been associated with increased corticotropin releasing hormone and may contribute to hypothalamic pituitary axis (HPA) hyperactivity. Elevated levels of the neuroactive steroids, allopregnanolone (3alpha,5alpha-THP) and 3alpha,5alpha-tetrahydrodeoxycorticosterone (THDOC) appear to counter-regulate HPA hyperactivity. Plasma essential fatty acids and neurosteroids were assessed among 18 male healthy controls and among 34 male psychiatric patients with DSM-III alcoholism, depression, or both. Among all subjects, lower plasma DHA was correlated with higher plasma THDOC (r = -0.3, P < 0.05) and dihydroprogesterone (DHP) (r = -0.52, P < 0.05). Among psychiatric patients lower DHA was correlated with higher DHP (r = -0.60, P < 0.01), and among healthy controls lower plasma DHA was correlated with higher THDOC (r = -0.83, P < 0.01) and higher isopregnanolone (3beta,5alpha-THP) (r = -0.55, P < 0.05). In this pilot observational study, lower long-chain omega-3 essential fatty acid status was associated with higher neuroactive steroid concentrations, possibly indicating increased feedback inhibition of the HPA axis.