Neuroendocrine and Inflammatory Effects of Mind-Body Interventions in Healthcare Workers: A Comprehensive Review

Abstract

Healthcare workers are exposed to sustained occupational demands arising from caseload, working hours, emotional labour and repeated acute clinical events. Prolonged exposure of this kind may affect hypothalamic-pituitary-adrenal (HPA) axis activity, autonomic regulation and inflammatory signalling. Yoga, mindfulness, meditation and structured breathing practices are increasingly offered to hospital staff, but their effect on objective biological markers of stress remains uncertain. In the first section of this review, the body's reaction to chronic stress and the mechanisms underlying the measurement of the stress response is discussed, as well as the nature of the stressors that the health care professions may encounter and the purported mechanism by which these mind–body techniques may be beneficial. We found six studies that evaluated the practices with healthcare workers that we will discuss. Cortisol was the most frequently reported outcome, and post-intervention concentrations were generally lower in the intervention groups. The size of this reduction differed considerably between studies, and one trial reported a reduction in the cortisol awakening response, the sharp rise in cortisol that follows waking, rather than in a single cortisol value. Interleukin-6 showed little change where complete data were available, CRP and hs-CRP tended to fall, and one study reported a reduction in TNF-α. Reporting was not uniform across studies, particularly with respect to the biological matrix sampled, the time of collection and the assay used, which limits the conclusions that may be drawn. Occupational exposures such as disturbed sleep and shift duty also influence the same markers, making the specific contribution of mind-body practice difficult to determine. The evidence is therefore suggestive rather than conclusive. What is needed is standardised sampling conditions, clearer reporting of how much practice participants actually completed, and studies that assess neuroendocrine, inflammatory and autonomic systems together in the same participants.