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

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.