Cardiovascular risk factors in multi-ethnic middle school students: the HEALTHY primary prevention trial

The objective of this study was to examine the effects of an integrated, multi-component, school-based intervention programme on cardiovascular disease (CVD) risk factors among a multi-ethnic cohort of middle school students.

HEALTHY was a cluster randomized, controlled, primary prevention trial. Middle school was the unit of randomization and intervention. Half of the schools were assigned to an intervention programme consisting of changes in the total school food environment and physical education classes, enhanced by educational outreach and behaviour change activities and promoted by a social marketing campaign consisting of reinforcing messages and images. Outcome data reported (anthropometrics, blood pressure and fasting lipid levels) were collected on a cohort of students enrolled at the start of 6th grade (∼11-12 years old) and followed to end of 8th grade (∼13-14 years old).

Forty-two middle schools were enrolled at seven field centres; 4363 students provided both informed consent and CVD data at baseline and end of study. The sample was 52.7% female, 54.5% Hispanic, 17.6% non-Hispanic Black, 19.4% non-Hispanic White and 8.5% other racial/ethnic combinations, and 49.6% were categorized as overweight or obese (body mass index ≥ 85th percentile) at baseline. A significant intervention effect was detected in the prevalence of hypertension in non-Hispanic Black and White males. The intervention produced no significant changes in lipid levels.

The prevalence of some CVD risk factors is high in minority middle school youth, particularly males. A multi-component, school-based programme achieved only modest reductions in these risk factors; however, promising findings occurred in non-Hispanic Black and White males with hypertension.