Normative distribution of complete blood count from early childhood through adolescence: the Bogalusa Heart Study

Abstract

Background: Noting the distribution of blood values in a biracial southern community according to age, sex, and race variations will help in understanding the normative developmental changes in early life and provides background information.

Methods: Complete blood counts were obtained from 3,018 free-living children ages 5-17 years from a well-defined black-white community as part of a cardiovascular risk factor screening.

Results: For children ages 5-17 years, hemoglobin levels, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, and red blood count increased (P < 0.01) with age. Levels of platelet count and white blood count decreased (P < 0.0005) with age. Compared with females, males between ages 12 and 17 years have (P < 0.05) 0.4 x 10(12)/liter higher red blood count, 1 g/dl higher hemoglobin, 2% higher hematocrit, 0.2 g/dl higher mean corpuscular hemoglobin concentration, 0.5 x 10(9)/liter lower white blood count, 1.4 fl lower mean corpuscular volume, 0.3 pg lower mean corpuscular hemoglobin, and 14 x 10(9)/liter lower platelet count. Compared with blacks, whites have (P < 0.05) 0.5 10(9)/liter higher white blood count, 0.05 10(12)/liter higher red blood count, 0.7 g/dl higher hemoglobin, 1.7% higher hematocrit, 2.4 fl higher mean corpuscular volume, 1 pg higher mean corpuscular hemoglobin, and 0.5 g/dl higher mean corpuscular hemoglobin concentration. A positive association was noted among blood count variables and hemoglobin with blood pressure similar to that in adults.

Conclusion: Blood values differ by age, sex, and race. These differences change at maturation and should be considered when defining normal and "abnormal" blood values.