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Relationships between skin color, income, and blood pressure among African Americans in the CARDIA Study
Quantitative Health Sciences Publications and Presentations
  • Elizabeth Sweet, Northwestern University
  • Thomas W. McDade, Northwestern University
  • Catarina I. Kiefe, University of Massachusetts Medical School
  • Kiang Liu, Northwestern University
UMMS Affiliation
Department of Quantitative Health Sciences
Publication Date
Document Type
Adolescent; Adult; *African Americans; *Blood Pressure; Cardiovascular Diseases; Female; *Health Status Disparities; Humans; *Income; Linear Models; Male; Multivariate Analysis; Risk Factors; *Skin Pigmentation; Socioeconomic Factors; Stress, Psychological; United States

OBJECTIVES: We explored how income and skin color interact to influence the blood pressure of African American adults enrolled in the longitudinal Coronary Artery Risk Development in Young Adults (CARDIA) Study.

METHODS: Data were derived from 1893 African American CARDIA year-15 participants who had undergone skin reflectance assessments at year 7. We adjusted for age, gender, body mass index, smoking status, and use of antihypertensive medication to examine whether year-15 self-reported family incomes, in interaction with skin reflectance, predicted blood pressure levels.

RESULTS: Mean systolic and diastolic blood pressure levels were 117.1 (+/-16.07) and 76.9 (+/-12.5) mm Hg, respectively. After adjustment, the interaction between skin reflectance and income was significantly associated with systolic blood pressure (P< .01). Among lighter-skinned African Americans, systolic pressure decreased as income increased (b= -1.15, P<.001); among those with darker skin, systolic blood pressure increased with increasing income (b=0.10, P=.75).

CONCLUSIONS: The protective gradient of income on systolic blood pressure seen among African Americans with lighter skin is not observed to the same degree among those with darker skin. Psychosocial stressors, including racial discrimination, may play a role in this relationship.

DOI of Published Version
Am J Public Health. 2007 Dec;97(12):2253-9. Epub 2007 Oct 30. Link to article on publisher's site
PubMed ID
Related Resources
Link to Article in PubMed
Citation Information
Elizabeth Sweet, Thomas W. McDade, Catarina I. Kiefe and Kiang Liu. "Relationships between skin color, income, and blood pressure among African Americans in the CARDIA Study" Vol. 97 Iss. 12 (2007) ISSN: 0090-0036 (Linking)
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