Chronic Stress, Cortisol Dysfunction, and Pain: A Psychoneuroendocrine Rationale for Stress Management in Pain Rehabilitation

Pain is a primary symptom driving patients to seek physical therapy, and its attenuation commonly defines a successful outcome. A large body of evidence is dedicated to elucidating the relationship between chronic stress and pain; however, stress is rarely addressed in pain rehabilitation. A physiologic stress response may be evoked by fear or perceived threat to safety, status, or well-being and elicits the secretion of sympathetic catecholamines (epinephrine and norepinepherine) and neuroendocrine hormones (cortisol) to promote survival and motivate success. Cortisol is a potent anti-inflammatory that functions to mobilize glucose reserves for energy and modulate inflammation. Cortisol also may facilitate the consolidation of fear-based memories for future survival and avoidance of danger. Although short-term stress may be adaptive, maladaptive responses (eg, magnification, rumination, helplessness) to pain or non–pain-related stressors may intensify cortisol secretion and condition a sensitized physiologic stress response that is readily recruited. Ultimately, a prolonged or exaggerated stress response may perpetuate cortisol dysfunction, widespread inflammation, and pain. Stress may be unavoidable in life, and challenges are inherent to success; however, humans have the capability to modify what they perceive as stressful and how they respond to it. Exaggerated psychological responses (eg, catastrophizing) following maladaptive cognitive appraisals of potential stressors as threatening may exacerbate cortisol secretion and facilitate the consolidation of fear-based memories of pain or non–pain-related stressors; however, coping, cognitive reappraisal, or confrontation of stressors may minimize cortisol secretion and prevent chronic, recurrent pain. Given the parallel mechanisms underlying the physiologic effects of a maladaptive response to pain and non–pain-related stressors, physical therapists should consider screening for non–pain-related stress to facilitate treatment, prevent chronic disability, and improve quality of life.



Treating fibromyalgia with mindfulness-based stress reduction: results from a 3-armed randomized controlled trial.

Mindfulness-based stress reduction (MBSR) is a structured 8-week group program teaching mindfulness meditation and mindful yoga exercises. MBSR aims to help participants develop nonjudgmental awareness of moment-to-moment experience. Fibromyalgia is a clinical syndrome with chronic pain, fatigue, and insomnia as major symptoms. Efficacy of MBSR for enhanced well-being of fibromyalgia patients was investigated in a 3-armed trial, which was a follow-up to an earlier quasi-randomized investigation. A total of 177 female patients were randomized to one of the following: (1) MBSR, (2) an active control procedure controlling for nonspecific effects of MBSR, or (3) a wait list. The major outcome was health-related quality of life (HRQoL) 2 months post-treatment. Secondary outcomes were disorder-specific quality of life, depression, pain, anxiety, somatic complaints, and a proposed index of mindfulness. Of the patients, 82% completed the study. There were no significant differences between groups on primary outcome, but patients overall improved in HRQoL at short-term follow-up (P=0.004). Post hoc analyses showed that only MBSR manifested a significant pre-to-post-intervention improvement in HRQoL (P=0.02). Furthermore, multivariate analysis of secondary measures indicated modest benefits for MBSR patients. MBSR yielded significant pre-to-post-intervention improvements in 6 of 8 secondary outcome variables, the active control in 3, and the wait list in 2. In conclusion, primary outcome analyses did not support the efficacy of MBSR in fibromyalgia, although patients in the MBSR arm appeared to benefit most. Effect sizes were small compared to the earlier, quasi-randomized investigation. Several methodological aspects are discussed, e.g., patient burden, treatment preference and motivation, that may provide explanations for differences. In a 3-armed randomized controlled trial in female patients suffering from fibromyalgia, patients benefited modestly from a mindfulness-based stress reduction intervention.