A review of age differences in the neurophysiology of nociception and the perceptual experience of pain

Objective: To better understand the nature of age differences in pain and nociception with the aging of the worlds' population. Methods: The evidence from numerous neurophysiologic and psychological studies suggest a small, but demonstrable age-related impairment in the early warning functions of pain. The increase in pain perception threshold and the widespread change in the structure and function of peripheral and CNS nociceptive pathways may place the older person at greater risk of injury. Moreover, the reduced efficacy of endogenous analgesic systems, a decreased tolerance of pain and the slower resolution of postinjury hyperalgesia may make it more difficult for the older adult to cope, once injury has occurred. Results: These age-related changes may be best conceptualized as a reduced capacity in the functional reserve of the pain system, at both ends of the intensity spectrum. Discussion: The clinical implications are obvious; older persons are likely to be especially vulnerable to the negative impacts of pain and pain associated events.