Adverse life events (ALEs) are a risk factor for persistent pain. Mechanisms underlying this association were explored in a study examining cumulative ALE exposure, pain perception and spinal nociceptive modulation in 124 healthy, pain-free Native Americans and 129 healthy, pain-free non-Hispanic Whites.1 Cumulative ALE exposure was assessed by summing the number of traumatic events experienced by each participant during their lifetime. Pain levels and the nociceptive flexion reflex (NFR) were assessed during a conditioned pain modulation (CPM) task.
Authors Kell and colleagues found low exposure to ALEs was associated with NFR inhibition, whereas high exposure to ALEs was associated with NFR facilitation, inferring ALEs may be pronociceptive for both Native Americans and non-Hispanic Whites by impairing descending inhibition of spinal nociception processes. They conclude diminished descending inhibition due to high ALS exposure could contribute an increase in spinal sensitization and persistent pain risk.
1Well PA, Hellman N, Huber FA, et al. The relationship between adverse life events and endogenous inhibition of pain and spinal nociception: Findings from the Oklahoma Study of Native American Pain Risk (OK-SNAP). J Pain. 2021 Sep;22(9):1097-1110.