The association of race and ethnicity with patch test results: North American Contact Dermatitis Group data, 2007-2020.

BACKGROUND

Few recent studies have examined differences in patch test results between racial/ethnic groups.

OBJECTIVE

To analyze patch test results by race/ethnicity in the United States and Canada.

METHODS

Retrospective cross-sectional analysis of 32,138 patch-tested patients, comparing results between White (non-Hispanic), Black, Asian, and Hispanic patients.

RESULTS

Most patients were White (86.5%) followed by Asian (6.8%), Black (4.8%), and Hispanic (2.0%). Thirteen of 50 allergens differed significantly across groups (all P < .001): nickel, cobalt, neomycin, p-phenylenediamine, disperse dyes, balsam of Peru, fragrance mix II, formaldehyde, quaternium-15, lanolin, propylene glycol, thiuram mix, and colophony. White patients had the highest proportion of positive patch test reactions to balsam of Peru, neomycin, quaternium-15, and fragrance mix II; Black patients had the highest proportion of reactions to p-phenylenediamine and disperse dyes; Asian patients had the highest proportion of reactions to nickel, cobalt, and thiuram mix; and Hispanic patients had the highest proportion of reactions to propylene glycol (all P < .001).

LIMITATIONS: Tertiary referral population with disproportionate representation by racial/ethnic groups. Race/ethnicity are social constructs.

CONCLUSION

Patch test results differ across racial/ethnic groups, which may relate to sociocultural variations in allergen exposures. These findings can facilitate allergen identification and avoidance in diverse populations.