Race Effects on Conditioned Pain Modulation in Youth

Race and ethnicity shape the experience of pain in adults. African Americans typically exhibit greater pain intensity and evoked pain responsiveness than non-Hispanic whites. However, it remains unclear whether there are racial differences in conditioned pain modulation (CPM) and if these are present in youth. CPM refers to a reduction in perceived pain intensity for a test stimulus during application of a conditioning stimulus and may be especially relevant in determining risk for chronic pain. The present study assessed CPM to evoked thermal pain in 78 healthy youth (ages 10-17 years), 51% of whom were African American and 49% of whom were non-Hispanic white. African American youth reported lower mean conditioning pain ratings than non-Hispanic white youth, controlling for mean preconditioning pain ratings, which is consistent with stronger CPM. Multilevel models demonstrated stronger CPM effects in African American than non-Hispanic white youth, as evident in more rapid within-person decreases in pain ratings during the conditioning phase. These findings suggest that diminished CPM likely does not account for the enhanced responsiveness to evoked thermal pain observed in African American youth. These results may have implications for understanding racial differences in chronic pain experienced in adulthood. Perspective: This study evaluated conditioned pain modulation to evoked thermal pain in African American and non-Hispanic white youth. Findings could have implications for the development of personalized chronic pain treatment strategies that are informed by race and ethnicity. (C) 2015 by the American Pain Society