Aims: This study aimed to evaluate the tracking pattern of serum total cholesterol (TC) levels among Japanese children using data collected continuously for 9 years and examine the relationship between childhood and adulthood TC levels.
Methods: TC levels of 2,608 first grade primary school children enrolled during 1981-2014 from two Japanese towns were measured during annual health check-ups. Nine-year trajectories of estimated TC levels stratified by TC quartiles in the first grade were analyzed using a mixed effects model. Adulthood TC levels were measured in participants who underwent health check-ups in the same area.
Results: Overall, 1,322 boys and 1,286 girls in the first grade of a primary school were followed for 9 years. Trajectories of TC levels during the period stratified by TC quartiles in the first grade differed significantly and did not cross each other for both sexes. Childhood data of 242 adult participants were linked with their adulthood data; the mean of age was late 20s for both sexes. The average TC levels in adulthood increased from the first to the fourth quartile in the first grade. Additionally, trajectories of TC levels differed between boys and girls. The later the admission year, the more elevated the TC levels in girls.
Conclusion: Among Japanese children, TC levels were strongly tracked from childhood to adolescence for 9 years, and elevated TC levels in childhood were related to elevated TC levels in adulthood. Maintaining appropriate TC levels during childhood may be important to prevent future coronary artery diseases.
Keywords: Childhood; Cholesterol level; Coronary Artery Diseases; Mixed effect model; Tracking pattern.