Linda Cook, NINR 301-496-0207 lc59t@nih.gov Renee Kinzie, UNC 919-966-1412 rkinzie@unc.edu
Called the Cardiovascular Health In Children study (CHIC), the investigation was led by Joanne Harrell, PhD, RN, of the School of Nursing at the University of North Carolina at Chapel Hill, and sponsored by the National Institute of Nursing Research (NINR), NIH. The findings from the CHIC study are described in the August 3 issue of PEDIATRICS.
This is the first study to test the program on children with at least two CVD risk factors and to compare the effectiveness of a classroom-wide program with a program providing more individualized interventions. These findings suggest the need for policy changes at the elementary school level to place new emphasis on health and physical activities that can reduce CVD in children’s later lives. The cost-effectiveness of the classroom approach is an added benefit, since the more individualized approach requires additional staff resources and is more difficult to integrate into the school day.
"A number of studies already indicate that heart disease can begin in childhood, which underscores the critical importance of reaching children early to instill healthy habits," said Patricia A. Grady, PhD, RN, Director of the NINR. "Furthermore, risk factors developed at an early age tend to remain throughout adulthood, where they can cause heart attack, stroke, or kidney failure. Dr. Harrell’s investigation provides encouraging evidence that we can act to counter these prevalent conditions -- starting with our children. And we can do it with limited resources."
CHIC research results showed that both classroom-wide and small intervention groups experienced relatively similar reductions in cholesterol, blood pressure, and body fat, as well as increases in health knowledge. When compared to the control group not receiving an intervention, however, the positive differences for both intervention groups were striking.
According to Dr. Harrell, "When we started, I hypothesized that the individualized approach would be more effective. As it turned out, the findings pointed to a more generalized intervention as the direction to take. The positive results of the more easily implemented classroom-wide approach were stronger and reached more children." Dr. Harrell speculates that the reason this approach is more successful is that it avoids stigmatization of children with risk factors, capitalizes on positive peer pressure, and includes children who are currently at low risk.
The CHIC study consisted of an eight-week randomized controlled trial of a subset of 422 children with CVD risk factors that were drawn from a larger study group of 2,207 children. These children were from 18 rural and urban schools across the stroke belt State of North Carolina. There were equal numbers of males and females in the study, and the racial distribution mirrored that of the State’s population (19% African- American, 77% Caucasian, 4% other).
The classroom-wide intervention group received instruction twice a week, provided by regular classroom teachers. The course included the importance of regular exercise and how to select heart-healthy foods. The children also received an aerobically focused physical education program three times a week. The small groups consisted of up to eight children, and the intervention was tailored to their individual risk factors. Physical activities were identical to the other, larger group. The control group received the usual classroom instruction and physical activities. At the start of the program, parents of all children participating in the study received information about their child’s cardiovascular risk status.
Recommending that the classroom-wide approach be used in elementary schools, Dr. Harrell believes that "This is an important challenge for our primary education system. Programs addressing health behaviors at an important time in children’s development should lower the Nation’s high incidence of CVD down the road."
Dr. Harrell is continuing her research to discover whether the children’s initial CVD health gains last over time. She is also investigating whether the knowledge or physical activity component of the intervention was more effective, and whether puberty will have an impact on risk factors. Another facet of the CHIC study is testing the intervention in 1,200 rural, ethnically diverse 6th through 8th grade students.
The NINR supports and conducts scientific research and research training to reduce the burden of illness and disability; improve health-related quality of life; and establish better approaches to promote health and prevent disease.
National Institute of Nursing Research Office of Science Policy and Information 31 Center Drive, Room 5B10 Bethesda, Maryland 20892-2178 (301) 496-0207 fax: (301) 480-4969