Anthropometry and blood pressure differences in black Caribbean, African, South Asian and white adolescents: the MRC...

In this first large-scale study of ethnic differences in blood pressure (BP) among British adolescents, we examine the differences in BP levels in adolescence and the extent to which age, sex, body size and stage of maturation affect any observed differences.

A total of 6365 11-13 year olds (including 1189 white, 907 black Caribbeans and 1056 black Africans, 473 Indians, 605 Pakistanis and Bangladeshis, and 548 of mixed ethnicity) had systolic blood pressure (SBP) and diastolic blood pressure (DBP), anthropometry and pubertal stage measured in 2003.

Compared with their white UK counterparts, black Caribbean and African boys were taller, and black Caribbean and African girls were taller, larger and matured earlier. Except for DBP among Indian girls, BP in minority groups was generally lower than in white UK children. Adjusted for age, height and body mass index, mean SBP was 109.1 mmHg (95% confidence interval 108.4, 109.8) and DBP 65.7 mmHg (65.2, 66.3) among white UK boys. Black Caribbean boys had lower SBP (-2.0; -3.2, -0.9 mmHg) and DBP (-1.5; -2.3, -0.6), and black African (-2.3; -3.4, -1.2) and mixed ethnicity (-1.6; -2.9, -0.3) boys had lower SBP. Adjusted SBP was 108.5 (107.8, 109.3) and DBP was 67.5 mmHg (66.9, 68.1) among white UK girls. Pakistani (-1.8; -3.2, -0.4) and black African (-1.1; -1.9, -0.3) girls had lower SBP and Indian girls (1.2; 0.1, 2.4) had higher DBP. Unlike African American girls, late puberty was not associated with higher BP in minority groups.

At these ages, the ethnic-specific patterns in BP in adulthood were not observed. Apart from higher DBP for Indian girls, BP in minority groups was generally lower than their white UK counterparts. Targeting intervention in adolescence may be a critical opportunity for preventing ethnic differences in BP in later life.