Stress responsiveness and adaptations of the neuroendocrine system in women with rheumatoid arthritis.

摘要

Rheumatoid arthritis (RA) is an autoimmune disease involving dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS), both integral to stress responses. Thus, RA provides a model for studying stress responses and chronic disease.; Study one investigated whether abnormal HPA axis and SNS function exist from disease onset. Women with ≤2 years of RA and control subjects participated in an acute stress reactivity challenge. Heart rate (HR), HR variability, blood pressure (BP), plasma ACTH and cortisol, and C-reactive protein (CRP) were measured in response to stressors. Baseline diastolic BP was elevated (p = .01) and cortisol responsiveness was decreased in RA (p .05). Both CRP and the CRP:ACTH ratio were significantly higher in RA. This supports the hypothesis of inherent hyporesponsiveness of the HPA axis in RA.; Study two investigated whether an acute yoga session would reduce HR and cortisol secretion, and increase diurnal cortisol secretion for women with RA. 75 minutes of yoga significantly decreased HR, but did not change salivary cortisol during yoga or over 24 hours. Some individuals had increased diurnal cortisol patterns after yoga, but a session did not significantly alter HPA axis hyporesponsiveness.; Study three investigated plasticity of the stress system in RA. 16 women with RA either participated in a 10-week yoga intervention (n = 9) with 3, 75-minute sessions/week or served as controls (n = 7). Physical function, measured with the Health Assessment Questionnaire (HAQ), the Berg Balance Test and a visual analog pain scale all improved significantly with yoga. Yoga also significantly decreased depression (Beck Depression Inventory). Acute stress responsiveness (HR, BP, salivary cortisol), assessed with stress reactivity testing pre- and post-yoga, did not change. Diurnal salivary cortisol secretion, measured pre- and post-intervention, did not change, although a trend toward greater cortisol awakening response in the yoga group was seen.; These studies support dysfunction of the HPA axis and SNS in RA, and the use of yoga as a means of improving function in RA. Given a longer intervention, yoga may also enhance responsiveness of the stress system.