Research examining clinical populations suggests stress plays a role in persistent pain and disability.[1–4] In addition, laboratory studies with rodents have illuminated possible peripheral mechanisms that could contribute to stress-induced hyperalgesia. In a study by Chen and colleagues, water avoidance stress produced mechanical hyperalgesia in skeletal muscle and an approximate 34% decrease in mechanical threshold of muscle nocicpetors, a nearly two fold increase in the number of action potentials produced by a prolonged, fixed intensity stimulus and an increase in conduction velocity from 1.25 m/s to 2.09 m/s.5 Study authors suggest these effects are due, at least in part, to catecholamines and glucocorticoids acting on adrenergic and glucocorticoid receptors on sensory neurons.
I always talk with patients about the role of stress in contributing to persistent pain. I explain this study in order to help people understand that pain can escalate, not because of tissue damage, but because of the possible effects of stress hormones on peripheral nerves. I introduce mindfulness as a self-management practice to promote the self-regulation of the stress reaction. This combination of patient education and mindfulness training empowers patients to take an active role in their treatment and self-regulate the sympathetic nervous system to promote pain relief.
1 McLean SA. The potential contribution of stress systems to the transition to chronic whiplash-associated disorders. Spine. 2011;36(25S):S226-32.
2 Menendez ME, Baker DK, Oladeji LO, et al. Psychological distress is associated with greater perceived disability and pain in patients presenting to a shoulder clinic. J Bone Joint Surg Am. 2015;97(24):1999-2003.
3 Mejdahl MK, Mertz BG, Bidstrup PE, et al. Preoperative distress predicts persistent pain after breast cancer treatment: a prospective cohort study. J Natl Compr Cancr Netw. 2015;13(8):995-1003.
4 Ross C, Juraskova I, Lee H, et al. Psychological distress mediates the relationship between pain and disability in hand or wrist fractures. J Pain 2015;16(9):836-43.
5 Chen X , Green PG, Levine JD. Stress enhances muscle nociceptor activity in the rat. Neuroscience 2011;185:166-73.