Modification of risk factors for coronary heart disease. Five-year results of a school-based intervention trial

Abstract

We conducted a study of the effectiveness of an educational intervention designed to modify risk factors associated with coronary heart disease among 3388 children in 37 schools in two demographically dissimilar areas (the Bronx and Westchester County) in and around New York City. Schools within each area were randomly assigned to either intervention or nonintervention groups. In schools targeted for intervention, children in the fourth through eighth grades were taught a teacher-delivered curriculum focusing on diet, physical activity, and cigarette smoking. Risk-factor levels were measured in all schools at base line and at four follow-up points. A total of 1769 of the children qualified for analysis of the intervention effect. After five years, the net mean change in plasma levels of total cholesterol was -1.7 mg per deciliter per year (-0.04 mmol per liter) (95 percent confidence interval, -2.7 to -0.7 mg per deciliter [-0.07 to -0.02 mmol per liter]) in the Westchester County schools, or -8.5 mg per deciliter (-0.22 mmol per liter) (5.1 percent) over a period of five years. In the schools in the Bronx, the net mean change was -1.0 mg per deciliter per year (-0.03 mmol per liter) (95 percent confidence interval, -2.3 to +0.3 mg per deciliter [-0.06 to +0.01 mmol per -2.3 to +0.3 mg per deciliter [-0.06 to +0.01 mmol per liter]), or -5.0 mg per deciliter (-0.13 mmol per liter) (2.9 percent) over a period of five years. Favorable trends in dietary intake and health knowledge were also observed, whereas the other targeted risk factors were not significantly altered. If these findings can be replicated, this will suggest that educational programs to modify coronary risk factors are feasible and may have a favorable (albeit small) effect on blood levels of cholesterol in children.