The Association of Skin Color With Blood Pressure in US Blacks With Low Socioeconomic Status

Abstract

To determine the association of skin color, measured by a reflectometer, with blood pressure in US blacks, we studied a community sample of 457 blacks from three US cities. Persons taking antihypertensive medications were excluded. Both systolic and diastolic blood pressure were higher in darker persons and increased by 2 mm Hg for every 1-SD increase in skin darkness. However, the association was dependent on socioeconomic status, whether measured by education or an index consisting of education, occupation, and ethnicity, being present only in person with lower levels of either indicator. Using multiple linear regression, both systolic and diastolic blood pressure remained significantly associated with darker skin color in the lower levels of socioeconomic status, independent of age, body mass index, and concentrations of blood glucose, serum urea nitrogen, serum uric acid, and urinary sodium and potassium. The association of skin color with blood pressure only in low socioeconomic strata may be due to the lesser ability of such groups to deal with the psychosocial stress associated with darker skin color. However, these findings also are consistent with an interaction between an environmental factor associated with low socioeconomic status and a susceptible gene that has a higher prevalence in persons with darker skin color.

Genetic ancestry influences asthma susceptibility and lung function among Latinos

“…30 In addition, for other diseases it has been suggested that the degree of African ancestry, as measured by skin color, is associated with disease due to a correlation with lower SES alone. 46,47 However, in this study, the association of African ancestry with asthma susceptibility remained statistically significant following adjustment for various measures of SES. Our findings are consistent with the observation of similar asthma prevalence in Puerto Rico across various income categories 48 and studies where SES similarly failed to explain an association of African ancestry with asthma-related traits.…”

Beyond Race/Ethnicity: Skin Color and Cardiometabolic Health Among Blacks and Hispanics in the United States

“…Our nationally representative results are consistent with research on skin color and health, which has found gradients in hypertension and BMI among Blacks in geographically limited samples. 23,24 Ours was the first study to incorporate diabetes, an important indicator of cardiometabolic syndrome. Among both Blacks and Hispanics, we found the strongest associations between ascribed skin color and diabetes risk.…”

“…21 Studies that have measured the association between skin color and one or more aspects of cardiometabolic health, using geographically limited, non-nationally representative samples of US Blacks, have found that darker skin color is associated with higher blood pressure and BMI. 23,24 Although less is known about the association between skin color and cardiometabolic health among US Hispanics, darker skin color is associated with poorer self-rated health among Hispanics in the United States and four Latin American countries. 15,25 …”

Research Needs to Improve Hypertension Treatment and Control in African Americans

“…2 In high income countries, including the US, mean BP and prevalence of hypertension is higher in adults self-described 3–6 , observer reported 7, 8 or otherwise identified 9, 10 as being black or having darker skin color. 11 However, the relationship between African origin and BP is absent or only minimally apparent in reports from middle-income countries. 12–14 Research to clarify reasons for this variability may contribute to understanding of hypertension-related racial disparities in the US.…”