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Updated: Jul 30, 2026

Assessment of Child Anthropometry in a Large Epidemiologic Study
Published on: February 2, 2017
Racial differences in the influence of body size on ambulatory blood pressure in youths
G A Harshfield1, P Barbeau, P A Richey
1Departments of Pediatrics, Medical College of Georgia, Augusta, Georgia 30912-4534, USA. Gharshfi@mail.mcg.edu
Background:
African Americans have higher night-time blood pressures than Caucasians do despite their having similar daytime blood pressures. It is well established that body size is related to casual blood pressure.
Objective:
To examine the influence of body size on racial differences in patterns of ambulatory blood pressure.
Methods:
Ambulatory blood pressure recordings were performed on 292 healthy children and adolescents (148 African Americans and 144 Caucasian) aged 10-18 years (mean 13+/-2 years). These blood pressures were related to height, weight, body surface area, and body mass index in separate regression models that also included race, sex, and age as factors.
Results:
The race-by-height interaction was significant for night-time systolic blood pressure (P<0.02), with a significant relationship for African Americans (P<0. 0001), but not for Caucasians. The race-by-weight interaction was significant for night-time systolic blood pressure (P<0.04), also with a greater relationship for African Americans (P<0.0001) than for Caucasians (P<0.03). In addition, the race-by-weight interaction was significant for night-time diastolic blood pressure (P<0.04), with a significant relationship for African Americans (P<0.01), but not for Caucasians. Finally, the race-by-body-surface-area interaction was significant for night-time diastolic blood pressure (P<0.05), again with a significant relationship for African Americans (P<0.02) but not for Caucasians.
Conclusion:
Differences in the relationship between body size and blood pressure contribute to the racial differences in patterns of ambulatory blood pressure and should be considered when evaluating patterns of blood pressure in African American youths.
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