Pigmentation in African American skin decreases with skin aging

Publication date: October 2016
Source:Journal of the American Academy of Dermatology, Volume 75, Issue 4
Author(s): Anna L. Chien, Jean Suh, Sabrina Sisto Alessi Cesar, Alexander H. Fischer, Nancy Cheng, Flora Poon, Barbara Rainer, Sherry Leung, Jo Martin, Ginette A. Okoye, Sewon Kang
BackgroundTristimulus colorimetry, which uses the Commission Internationale de l'Eclairage L*a*b* model to quantify color, has previously been used to analyze pigmentation and erythema in human skin; however, colorimetry of African American skin is not well characterized.ObjectiveWe sought to analyze skin color patterns in African Americans and compare them with those of Caucasians.MethodsColorimetry readings of the sun-protected buttock and sun-exposed back of forearm were taken from 40 Caucasian and 43 African American participants from March 2011 through August 2015. African American participants also completed a lifestyle questionnaire. Correlation coefficients, paired t tests, and multivariable linear regression analyses were used for statistical comparisons.ResultsForearm skin was lighter in African Americans ages 65 years and older versus 18 to 30 years (P = .02) but darker in Caucasians ages 65 years or older versus 18 to 30 years (P = .03). In African Americans ages 18 to 30 years, the buttock was darker than the forearm (P < .001), whereas in Caucasians the buttock was lighter than the forearm (P < .001). A lighter forearm than buttock was correlated with supplement use, smoking (ages 18-30 years), and less recreational sun exposure (ages ≥65 years) in African Americans.LimitationsOur study was limited by the sample size and focal geographic source.ConclusionsPigmentation patterns regarding sun-protected and sun-exposed areas in African Americans may differ from that of Caucasians, suggesting that other factors may contribute to skin pigmentation in African Americans.



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