Factors related to tracking of blood pressure in children. U.S. National Center for Health Statistics Health Examination Surveys Cycles II and III.

In this paper we examine the relationship of growth, obesity, and the degree of sexual and bone maturation to blood pressure in a U.S. national probability sample of 2165 children examined by the U.S. National Center for Health Statistics on two occasions, approximately 4 years apart. Subjects who maintained, increased, or decreased their peer rank order of blood pressure are described. Children who maintained their blood pressure in the upper quintile were taller, heavier, more obese, had greater bone age, greater numbers of permanent teeth, and were more sexually mature than their peers, while those maintaining their blood pressure in the lowest quintile of blood pressure were shorter, lighter, less obese, had lesser bone age, fewer permanent teeth, and were less sexually mature. Subjects whose blood pressures were initially in the lowest four quintiles and then rose to the top quintile were also taller, heavier, more obese, and had greater bone age, while those with blood pressures falling to the lowest quintile from the upper four quintiles were shorter, lighter, less obese, and had lesser bone age. Thus, the level at which blood pressure tracks during childhood is related to growth, obesity, and to the degree of maturation acquired. In addition, children whose blood pressures are rising or falling in relation to their peers have body growth and maturation characteristics similar to those who maintain their rank order high or low respectively.