Pigmentation in African American skin decreases with skin aging.
BACKGROUND
Tristimulus 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.


OBJECTIVE
We sought to analyze skin color patterns in African Americans and compare them with those of Caucasians.


METHODS
Colorimetry 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.


RESULTS
Forearm 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.


CONCLUSIONS
Our study was limited by the sample size and focal geographic source.


CONCLUSIONS
Pigmentation 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.
Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland. Electronic address: achien3@jhmi.edu.
Anna L
AL
Chien
Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Jean
J
Suh
Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Sabrina Sisto Alessi
SSA
Cesar
Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Alexander H
AH
Fischer
Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Nancy
N
Cheng
Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Flora
F
Poon
Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Barbara
B
Rainer
Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Sherry
S
Leung
Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Jo
J
Martin
Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Ginette A
GA
Okoye
Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Sewon
S
Kang
D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data*; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000502:physiology; D015331:Cohort Studies; D005500:Follow-Up Studies; D006801:Humans; D017496:Hypopigmentation / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010858:Pigmentation / Q000502:physiology*; D012189:Retrospective Studies; D018570:Risk Assessment; D015595:Skin Aging / Q000502:physiology*; D044465:White People / Q000706:statistics & numerical data*; D055815:Young Adult
African Americans; Caucasians; aging; colorimetry; ethnic skin; sun-exposed skin; sun-protected skin