TY - JOUR
T1 - Ethnic disparities in pain processing among healthy adults
T2 - -opioid receptor binding potential as a putative mechanism
AU - Letzen, Janelle E.
AU - Mun, Chung Jung
AU - Kuwabara, Hiroto
AU - Burton, Emily F.
AU - Boring, Brandon L.
AU - Walls, Taylor
AU - Speed, Traci J.
AU - Wong, Dean F.
AU - Campbell, Claudia M.
N1 - Funding Information:
The present work was funded by grants from the National Institutes of Health to Drs C.M. Campbell (R01MD009063, Blaustein Pain Research Foundation Grant), Janelle Letzen (F32HL143941), and C.J. Mun (T32NS070201 as a postdoctoral fellow and F32DA049393), as well as Shared Instrument Grants to Dr D.F. Wong (S10RR023623 & S10RR017219).
Publisher Copyright:
© 2020 Lippincott Williams and Wilkins. All rights reserved.
PY - 2020/4/1
Y1 - 2020/4/1
N2 - Although ethnic differences in pain perception are well documented, the underlying mechanism for these outcomes has not been established. µ-opioid receptor (MOR) function might contribute to this disparity, given that MORs play a key role in pain sensitivity and modulation. However, no study has characterized ethnic differences in MOR physiology. This study sought to address this knowledge gap by examining differences in µ-selective agonist binding potential (BPND; [11C]-Carfentanil) between 27 non-Hispanic black (NHB) and 27 demographically similar, non-Hispanic white participants. Participants completed questionnaires and two 90-minute high-resolution research tomograph positron emission tomography (PET) imaging sessions. During PET imaging, a capsaicin or control cream was applied to individuals' arms, and pain ratings were collected. Bonferroni-corrected PET volumes of interest analyses revealed significantly greater [11C]-Carfentanil BPNDamong NHB participants in bilateral ventral striatum ([left]: F1,52= 16.38, P < 0.001; [right]: F1,52= 21.76, P < 0.001), bilateral dorsolateral prefrontal cortex ([left] F1,52= 17.3, P < 0.001; [right]: F1,52= 14.17, P < 0.001), bilateral subgenual anterior cingulate cortex ([left]: F1,52= 10.4, P = 0.002; [right]: F1,52= 12.91, P = 0.001), and right insula (F1,52= 11.0, P = 0.002). However, there were no significant main effects of condition or ethnicity × condition interaction effects across models, likely attributable to individual variability in the direction of change within groups. BPNDvalues were significantly correlated with pain ratings collected during the capsaicin condition (r range = 0.34-0.46, P range = 0.01-0.001). Results suggest that NHB individuals might have generally greater unoccupied MOR density than non-Hispanic white peers. Findings have implications for physiological differences underlying ethnicity-related pain disparities. If replicated, these results further emphasize the need for tailored treatments in historically underserved populations.
AB - Although ethnic differences in pain perception are well documented, the underlying mechanism for these outcomes has not been established. µ-opioid receptor (MOR) function might contribute to this disparity, given that MORs play a key role in pain sensitivity and modulation. However, no study has characterized ethnic differences in MOR physiology. This study sought to address this knowledge gap by examining differences in µ-selective agonist binding potential (BPND; [11C]-Carfentanil) between 27 non-Hispanic black (NHB) and 27 demographically similar, non-Hispanic white participants. Participants completed questionnaires and two 90-minute high-resolution research tomograph positron emission tomography (PET) imaging sessions. During PET imaging, a capsaicin or control cream was applied to individuals' arms, and pain ratings were collected. Bonferroni-corrected PET volumes of interest analyses revealed significantly greater [11C]-Carfentanil BPNDamong NHB participants in bilateral ventral striatum ([left]: F1,52= 16.38, P < 0.001; [right]: F1,52= 21.76, P < 0.001), bilateral dorsolateral prefrontal cortex ([left] F1,52= 17.3, P < 0.001; [right]: F1,52= 14.17, P < 0.001), bilateral subgenual anterior cingulate cortex ([left]: F1,52= 10.4, P = 0.002; [right]: F1,52= 12.91, P = 0.001), and right insula (F1,52= 11.0, P = 0.002). However, there were no significant main effects of condition or ethnicity × condition interaction effects across models, likely attributable to individual variability in the direction of change within groups. BPNDvalues were significantly correlated with pain ratings collected during the capsaicin condition (r range = 0.34-0.46, P range = 0.01-0.001). Results suggest that NHB individuals might have generally greater unoccupied MOR density than non-Hispanic white peers. Findings have implications for physiological differences underlying ethnicity-related pain disparities. If replicated, these results further emphasize the need for tailored treatments in historically underserved populations.
KW - Endogenous pain modulation
KW - Ethnic differences
KW - Mu-opioid receptors
KW - Neuroreceptor imaging
KW - PET
KW - [C]-Carfentanil
UR - http://www.scopus.com/inward/record.url?scp=85082147896&partnerID=8YFLogxK
U2 - 10.1097/j.pain.0000000000001759
DO - 10.1097/j.pain.0000000000001759
M3 - Article
C2 - 31764386
AN - SCOPUS:85082147896
SN - 0304-3959
VL - 161
SP - 810
EP - 820
JO - Pain
JF - Pain
IS - 4
ER -