Is the SPRINT Blood Pressure Treatment Target of 120/80 mm Hg Relevant for Children?

The Systolic Blood Pressure Intervention Trial (SPRINT), conducted on older adults with markedly elevated risk for cardiovascular events, demonstrated significant outcome benefit with treatment of blood pressure (BP) to a goal of ≤120/80 mm Hg. Results of the SPRINT trial would not seem generalizable to children and adolescents because the SPRINT focus was on older adults at high risk for cardiovascular events. Inclusion criteria for sprint were elevated BP and additional high-risk criteria including Framingham risk score >15%, prior cardiovascular disease, reduced glomerular filtration rate, or age >75 years. This trial seems far removed from a pediatric setting. However, the relevance of SPRINT, when one considers pediatric prevention, is that hypertension accelerates cardiovascular disease. With the exception of age, SPRINT inclusion criteria are often consequences of long-standing hypertension. The success of SPRINT raises the question of whether there is benefit from lifelong BP <120/80 mm Hg. Substantial data on hypertension in adults link adverse cardiovascular outcomes with BP levels >140/90 mm Hg, thus supporting pharmacological treatment for primary prevention of cardiovascular events. Based on a body of epidemiological data demonstrating a rise in cardiovascular risk beginning at a BP level ≥120/80 mm Hg, the Joint National Commission 7 (JNC7) guidelines on hypertension in adults introduced the concept of prehypertension for BP levels from 120/80 to 139/89 mm Hg. The intent was to alert patients to modify lifestyle behaviors to prevent further rise in BP. There are no data that link a BP threshold in childhood with cardiovascular events decades later in adulthood. Children have lower BP than adults. BP levels in children increase with age, and by early to midadolescence, the likelihood of a child meeting the JNC VII criteria for prehypertension passes 10%. Beginning in the 1970s, hypertension in childhood has been defined statistically as BP levels that exceed the 95th percentile of the normative BP distribution. The 95th percentile was a conservative estimate of high BP in childhood that was originally intended to enable detection of children with secondary hypertension. The 95th percentile is well below the conventional adult threshold defining hypertension of 140/90 mm Hg especially in younger children. Using the criteria of BP level ≥95th percentile on repeated measurement, the prevalence childhood hypertension is ≈3.5% and includes primary as well as secondary hypertension. Prehypertension in childhood was defined as systolic or diastolic BP ≥90th percentile and <95th percentile. Beginning at 12 years of age, systolic BP levels at the 90th percentile are greater than the adult prehypertension threshold of 120 mm Hg. To be consistent with the adult definition, prehypertension in adolescence was adjusted to BP ≥120/80 to <95th percentile from age 12 years through adolescence. Thus, 120/80 mm Hg became an easy BP number to remember and also a BP level that defined some level of risk. The normal rise in BP in childhood is related to growth as well as age. Reference tables that provide the BP value for the 90th, and 95th percentile are determined by sex, age, and height in childhood. These tables are complex and cumbersome to use, especially in primary pediatric care. Although BP measurement has become routine in pediatric health encounters, because of the complexity of the BP reference tables, abnormal BP levels are frequently not identified in asymptomatic children and adolescents. It would be a great advantage to have a single number as a BP threshold to separate children with normal BP and from those for whom the BP tables should be consulted. Another new recommendation in the 2004 childhood BP guidelines was the recommendation that evaluation of a child with confirmed hypertension also include an evaluation for target organ damage. Subsequent clinical studies reported echocardiographic evidence of left ventricular hypertrophy in a substantial portion of hypertensive children and adolescents. Evidence for target organ damage in hypertensive youth now includes vascular stiffness and increased carotid intimal thickness. Moreover, left ventricular hypertrophy has also been reported in adolescents with prehypertension. In addition, there is emerging evidence that obesity in childhood also contributes to increases in cardiac mass that are in addition to BP level. These reports call attention to the fact that a BP level of 120/80 mm Hg in adolescence may already be associated with early cardiovascular target organ damage. Based on recent BP data on children and adolescents from the National Health and Nutrition Examination Surveys, ≈10% of adolescents enter young adulthood with a BP ≥120/80 mm Hg. The importance of BP of 120 to 139/80 to 89 mm Hg measured at age 18 to 30 years for the development of cardiovascular target organ damage in middle age has been emphasized in the Coronary Artery Risk Development in Young Adults study. When coronary artery calcium assessed on computerized The opinions expressed in this editorial are not necessarily those of the editors or of the American Heart Association. From the Departments of Medicine and Pediatrics (B.F.), Thomas Jefferson University, Philadelphia, PA; and Department of Pediatrics, Nemours/A.I. DuPont Hospital for Children, Wilmington, DE (S.S.G.). Correspondence to Bonita Falkner, Thomas Jefferson University, 833 Chestnut St. Ste.700, Philadelphia, PA 19107. E-mail bonita.falkner@ jefferson.edu Is the SPRINT Blood Pressure Treatment Target of 120/80 mm Hg Relevant for Children?