Ethnic differences in responses to multiple experimental pain stimuli

A growing body of literature suggests that the experience of clinical pain differs across ethnocultural groups. Additionally, some evidence indicates greater sensitivity to experimentally induced pain among African Americans; however, most studies have included only one pain modality. This study examined ethnic differences in responses to multiple experimental pain stimuli, including heat pain, cold pressor pain, and ischemic pain. Heat pain threshold and tolerance, ratings of repetitive suprathreshold heat, and ischemic and cold pressor pain threshold and tolerance were assessed in 120 (62 African American, 58 white) healthy young adults. Also, several psychological instruments were administered. No ethnic group differences emerged for threshold measures, but African Americans had lower tolerances for heat pain, cold pressor pain and ischemic pain compared to whites. Ratings of intensity and unpleasantness for suprathreshold heat stimuli were significantly higher among African Americans. African Americans reported greater use of passive pain coping strategies and higher levels of hypervigilance. Controlling for passive pain coping did not account for group differences in pain responses, while controlling for hypervigilance rendered group differences in heat pain tolerance and ischemic pain tolerance non-significant. These findings demonstrate differences in laboratory pain responses between African Americans and whites across multiple stimulus modalities, and effect sizes for these differences in pain tolerance were moderate to large for suprathreshold measures. Hypervigilance partly accounted for group differences. Additional research to determine the mechanisms underlying these effects is warranted.