Muscatine Study

Background/Question:

This study sought to determine the distribution of serum cholesterol and serum triglyceride levels, blood pressure, and body weight in a school-age population and trends of these characteristics over time. Little was known about risk in children at the onset. By determining the distribution of these factors, a high-risk group could be identified and treated to prevent adult diseases.

Population/Methods:

The study looked at 4,829 students in Muscatine, Iowa, ranging in age from 6 to 18. The genders were equally represented with 2,346 boys and 2,483 girls and examinations were carried out over two school years (1971-72 and 1972-73). 962 children had a dietary history of their breakfast taken in addition to other tests that included a blood sample and measuring blood pressure, height, body weight, and triceps skinfold thickness.

Results:

Serum cholesterol levels were similar for boys and girls, with a mean for all subjects of 182 mg/dl (SD 29) and the levels increased with age. Serum triglyceride levels were also similar and increased with age. Dietary histories showed that only a small percentage ate a high fat breakfast (9%) and that serum cholesterol levels were not related to amount of fat in the breakfast. Both systolic and diastolic blood pressures increased with age, with a steeper rise for boys. Body mass was greater than described in the standard Iowa Growth and Stuart (Harvard) Growth Charts. Cross sectional analysis showed that serum cholesterol levels, the number of children with high blood pressure, and relative weights at adult risk levels, all were greater in the older age ranges.

Later follow-ups found that a systolic blood pressure high at least once, indicates a risk that the child will have systolic blood pressure in the upper decile as an adult is twice as high as the rest of the population. A single high diastolic blood pressure was not associated with increased risk, but multiple high readings were. A second later study followed cholesterol levels in the childhood population and concluded that multiple cholesterol screenings in childhood led to incorrect classification of the likelihood of having high cholesterol as an adult, thus questioning the value of childhood cholesterol screening. A third study showed that increased physical activity during adolescence resulted in lower likelihood of obesity and more favorable young adult systolic blood pressure and lipid outcomes.

Conclusions/Discussion:

This study shows that a large proportion of children are already at risk for adult coronary heart disease, based on predictions from adult risk factor data. (FB/HB)