There is increasing evidence that adult hypertension (HTN) has its antecedents during childhood, as childhood blood pressure (BP) predicts adult BP [1,2]. HTN in childhood and adolescence may contribute to premature atherosclerosis and the early development of cardiovascular disease (CVD). As a result, identifying children with HTN and successfully treating their HTN may have an important impact on long-term outcomes of CVD. (See "Risk factors and development of atherosclerosis in childhood", section on 'Atherosclerotic changes in childhood' and "Risk factors and development of atherosclerosis in childhood", section on 'Hypertension' and "Treatment of hypertension in children and adolescents", section on 'Rationale for intervention'.)
The definition and diagnosis of HTN in children will be reviewed here. The risk factors, epidemiology, etiology, evaluation, and treatment of HTN in children are discussed separately. (See "Epidemiology, risk factors, and etiology of hypertension in children and adolescents" and "Evaluation of hypertension in children and adolescents" and "Treatment of hypertension in children and adolescents".)
United States — The National High Blood Pressure Education Program Working Group (NHBPEP) established guidelines for the definition of normal and elevated blood pressures in children in 1987 . These guidelines were updated in 2004 .
The definition of childhood hypertension (HTN) is based upon the normative distribution of blood pressure (BP) in healthy children. This is in contrast to adult HTN, which is primarily defined by clinical outcome data (ie, risk of cardiovascular disease and mortality) from large trials of antihypertensive therapy [3-5]. This clinical definition cannot be applied to children because cardiovascular (CV) events other than left ventricular hypertrophy do not typically occur until adulthood. (See "Overview of hypertension in adults".)
Body size is the most important determinant of BP in children and adolescents. Thus, classification of BP is more accurate when the values are adjusted for height as well as age and gender to avoid misclassifying children at the extremes of normal growth [4,6].