Emergence of ethnic differences in blood pressure in adolescence: the determinants of adolescent social well-being and health longitudinal study
- 1Medical Research Council, Social and Public Health Sciences Unit, University of Glasgow, Glasgow, UK
- 2Division of Cardiovascular and Endocrine Sciences, University of Manchester, Manchester, UK
Objective
To examine ethnic differences in changes in Blood Pressure (BP) between early and late adolescence in the UK.
Design
Determinants of Adolescent Social well-being and Health (DASH) study: A cohort observational study.
Setting
Schools in ten London boroughs with high proportions of the main ethnic minority groups, UK.
Participants
White British (692), Black Caribbeans (670), Black Africans (772), Indians (384), and Pakistanis and Bangladeshis (402) children were surveyed in 2003/2004 (11–13 years) and followed up in 2005/2006 (14–16 years).
Main outcome measures
Longitudinal measures of systolic (sBP) and diastolic BP (dBP). Predicted age, gender and ethnic specific mean BP, adjusted for anthropometry (Body mass index (BMI), height, weight, leg length (LL)), smoking, socio-economic circumstances (SEC) and psychological well-being were derived using mixed models.
Results
Among boys, sBP did not differ by ethnicity at 12 y but the greater increase among Black Africans than Whites led to higher sBP at 16 y (+2.9 mm Hg). The age trends for dBP suggest earlier divergences and increasing disparities with significantly higher dBP than Whites from 12 y for Indians, 14 y for Pakistanis-Bangladeshis and from 15 y for Black Africans. Among girls, ethnic differences in mean sBP were not significant at any age but larger increases were observed for Black Caribbeans and Black Africans than for Whites. At 12 y, dBP was lower among Black Caribbean and African girls than White girls but the faster rise led to similar levels by 14 y. Indians had significantly higher dBP from 13 y and Pakistanis/Bangladeshis from 15 y. Body mass index, height and leg length were independent predictors of BP, with few ethnic specific effects. Socio-economic disadvantage had a disproportionate effect on BP for girls in minority groups.
Conclusions
The findings suggest that ethnic divergences in BP begin in adolescence, particularly striking for boys. They signal the need for early prevention of adverse CVD risks in later life.
