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Measurement of blood pressure in children
AJH
2001; 14:976 –977
Editorials
Measurement of Blood Pressure in Children Alan Sinaiko
B
lood pressure measurement became a routine part of the pediatric physical examination only 25 years ago following publication of the first Task Force Report on Blood Pressure Control in Children.1 Since that time, additional Task Force reports in 19872 and 19973 have established the currently used standards for blood pressure and defined hypertension in children according to gender, age, and height. Prior to the first Task Force report, blood pressure was measured infrequently in children. There was a general feeling that virtually all hypertension in children was secondary to some other disease process, ie, primarily renal, and most cases of hypertension, regardless of degree of blood pressure elevation, were aggressively evaluated and treated. As pediatricians began to measure blood pressure in their patients on a regular basis, it became clear that many cases of mild to moderate hypertension were not related to other diseases, and the diagnosis of essential hypertension began to creep into pediatric practice, particularly in the adolescent age group. There is little controversy about initiating antihypertensive therapy in patients with secondary forms of hypertension because of the usual chronicity of the problem and the documented beneficial effects to preservation of renal function. However, there is greater reluctance to begin treatment in a child with mild hypertension, without better scientific information about the natural history of blood pressure in the transition from childhood to adulthood and the long-term effects of the therapy. Thus, there is a need to ensure accuracy of blood pressure measurement to carefully select patients for evaluation and treatment. The prevalence of hypertension in children is low. Using the Task Force protocol, ie, measurement of blood pressure on multiple occasions to eliminate the accommodation effect of measurement and regression toward the mean, the prevalence of systolic and diastolic hypertension was 0.8% and 0.4%, respectively, after two separate measurements in a population of 14,686 African American and white 10 –15 year olds.4 Despite this low prevalence, the introduction of 24-h ambulatory blood pressure measurement (ABPM) to clinical practice has raised questions about the accuracy of auscultation in the diagnosis of hypertension and the relevance of white coat hypertension
in the pediatric population. The paper by Sorof et al, in this issue of the Journal,5 begins to answer some of these questions. It compares ABPM with casual blood pressures in a sample of 71 American children but relies on normative ABPM standards developed from data obtained in 1141 white European children.6 Normative ABPM data on other cohorts also have been published.7–9 However, all of these data sets are relatively small, raising questions about their applicability to general populations and other ethnic groups. Based on the Task Force experience, in which increasing the size of the population base from the first1 to the second2 Task Force report strengthened the standard blood pressure distributions and altered the levels of blood pressure used to define hypertension in children, emphasis should be placed on obtaining ABPM blood pressure data from a considerably larger and more diverse population of normal children so as to establish reliable ABPM standards. A nagging issue limiting the incorporation of ABPM into pediatric practice has been lack of clear, carefully defined indications for its use. Sorof et al5 make a valuable contribution to the pediatric ABPM literature by showing that the frequency of white coat hypertension is inversely related to the degree of hypertension, as determined from casual measurements. White coat hypertension was found in only 15% of patients with blood pressure 20% above normal levels, but was present in 52% of patients with blood pressure 10% above normal. They correctly conclude that ABPM does not add substantially to the accurate identification of children with moderate to severe hypertension. They also conclude that these data support the use of ABPM in children with mild hypertension, but the evidence for this is less convincing. Of the 71 patients in this study, 65% were males who were generally overweight (mean body mass index [BMI] ⫽ 28.5 kg/m2) and older than the females; this is the expected demographic picture in pediatric population studies for children at the higher percentiles of blood pressure distribution. Most clinicians would be reluctant to initiate pharmacologic treatment in children with mild hypertension, particularly without first attempting non-pharmacologic intervention emphasizing weight loss and exercise. Even if white coat hypertension is identified in this group, studies confirming
Received April 18, 2001. Accepted May 30, 2001. From the Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN.
Address correspondence and reprint requests to Alan Sinaiko, MD, University of Minnesota Medical School, Box 491, 420 Delaware Street SE, Minneapolis, MN 55455; e-mail: [email protected]
0895-7061/01/$20.00 PII S0895-7061(01)02199-9
© 2001 by the American Journal of Hypertension, Ltd. Published by Elsevier Science Inc.
AJH–September 2001–VOL. 14, NO. 9, PART 1
the significant correlation between childhood weight and BMI with adult cardiovascular risk factors10 dictate that these children should not be ignored and that weight control and exercise strategies should be initiated. Thus, based on the data from this study it is not clear how, at the present time, ABPM contributes significantly to the clinical management of childhood hypertension. Mean blood pressure is increasing in the childhood population,11 suggesting that larger numbers of children with mild to moderate hypertension will be identified in coming years. The strong tracking effect for blood pressure between childhood and adulthood and the significant relation between blood pressure and other cardiovascular risk factors in childhood is evidence enough to encourage ongoing intensive investigation into blood pressure-related issues during the first two decades. Critical to these studies is an ability to precisely measure blood pressure to obtain basic information about blood pressure patterns, to identify hypertensive individuals, and to develop blood pressure data in clinical studies. As shown in adult studies,12 ABPM has the potential to serve that role. If ABPM were easily available, easier to administer, and inexpensive, it would probably be more widely used in children and broader-based ABPM standards would have been established by now. However, this is not the case and more compelling evidence needs to be presented to justify the addition of ABPM to routine pediatric practice.
References 1.
Task Force on Blood Pressure Control in Children-1997: Pediatrics 1997;59:797– 820.
EDITORIAL
2.
977
Task Force on Blood Pressure Control in Children-1987: Report of the second task force on blood pressure control in children-1987. Pediatrics 1987;79:1–25. 3. Update on the Task Force (1987) on high blood pressure in children and adolescents. A working group from the National High Blood Pressure Education Program. Pediatrics 1996;98:649 – 658. 4. Adrogue HE, Sinaiko AR: Prevalence of hypertension in junior high school-aged children: effect of new recommendations in the 1996 updated task force report. Am J Hypertens 2001;14:412– 414. 5. Sorof JM, Poffenbarger T, Franco K, Portman R: Evaluation of white coat hypertension in children: importance of the definitions of “normal” ambulatory blood pressure and the severity of casual hypertension. Am J Hypertens 2001;14:855– 860. 6. Soergel M, Kirschstein M, Busch C, Danne T, Gellermann J, Holl R, Drull F, Reichert H, Reusz GS, Rascher W: Oscillometric twentyfour-hour ambulatory blood pressure values in healthy children and adolescents: a multicenter trial including 1141 subjects. J Pediatrics 1997;130:178–184. 7. Harshfield GA, Alpert BS, Pulliam DA, Somes GW, Wilson DK: Ambulatory blood pressure recordings in children and adolescents. Pediatrics 1994;94:180–184. 8. Lurbe E, Redin J, Liao Y, Tacons J, Cooper RS, Alvarez V: Ambulatory blood pressure monitoring in normotensive children. J Hypertens 1994;12:1417–1423. 9. Reichert H, Lindinger A, Frey O, Mortzeck J, Kiefer J, Busch C, Hoffman W: Ambulatory blood pressure monitoring in healthy school children. Pediatr Nephrol 1995;9:282–286. 10. Sinaiko AR, Donahue RP, Jacobs DR, Prineas RJ: Relation of rate of growth during childhood and adolescence to fasting insulin, lipids, and systolic blood pressure in young adults. Circulation 1999;99:1471–1476. 11. Luepker R, Prineas RJ, Jacobs DR, Sinaiko AR: Secular trends of blood pressure and body size in a multi-ethnic adolescent population: 1986 –1996. J Pediatrics 1999;134:668– 674. 12. Mallion JM, Baquet JP, Siche JP, Tremel F, DeGaudemaris R: Clinical value of ambulatory blood pressure monitoring. J Hypertens 1999;17:585–595.
2001; 14:976 –977
Editorials
Measurement of Blood Pressure in Children Alan Sinaiko
B
lood pressure measurement became a routine part of the pediatric physical examination only 25 years ago following publication of the first Task Force Report on Blood Pressure Control in Children.1 Since that time, additional Task Force reports in 19872 and 19973 have established the currently used standards for blood pressure and defined hypertension in children according to gender, age, and height. Prior to the first Task Force report, blood pressure was measured infrequently in children. There was a general feeling that virtually all hypertension in children was secondary to some other disease process, ie, primarily renal, and most cases of hypertension, regardless of degree of blood pressure elevation, were aggressively evaluated and treated. As pediatricians began to measure blood pressure in their patients on a regular basis, it became clear that many cases of mild to moderate hypertension were not related to other diseases, and the diagnosis of essential hypertension began to creep into pediatric practice, particularly in the adolescent age group. There is little controversy about initiating antihypertensive therapy in patients with secondary forms of hypertension because of the usual chronicity of the problem and the documented beneficial effects to preservation of renal function. However, there is greater reluctance to begin treatment in a child with mild hypertension, without better scientific information about the natural history of blood pressure in the transition from childhood to adulthood and the long-term effects of the therapy. Thus, there is a need to ensure accuracy of blood pressure measurement to carefully select patients for evaluation and treatment. The prevalence of hypertension in children is low. Using the Task Force protocol, ie, measurement of blood pressure on multiple occasions to eliminate the accommodation effect of measurement and regression toward the mean, the prevalence of systolic and diastolic hypertension was 0.8% and 0.4%, respectively, after two separate measurements in a population of 14,686 African American and white 10 –15 year olds.4 Despite this low prevalence, the introduction of 24-h ambulatory blood pressure measurement (ABPM) to clinical practice has raised questions about the accuracy of auscultation in the diagnosis of hypertension and the relevance of white coat hypertension
in the pediatric population. The paper by Sorof et al, in this issue of the Journal,5 begins to answer some of these questions. It compares ABPM with casual blood pressures in a sample of 71 American children but relies on normative ABPM standards developed from data obtained in 1141 white European children.6 Normative ABPM data on other cohorts also have been published.7–9 However, all of these data sets are relatively small, raising questions about their applicability to general populations and other ethnic groups. Based on the Task Force experience, in which increasing the size of the population base from the first1 to the second2 Task Force report strengthened the standard blood pressure distributions and altered the levels of blood pressure used to define hypertension in children, emphasis should be placed on obtaining ABPM blood pressure data from a considerably larger and more diverse population of normal children so as to establish reliable ABPM standards. A nagging issue limiting the incorporation of ABPM into pediatric practice has been lack of clear, carefully defined indications for its use. Sorof et al5 make a valuable contribution to the pediatric ABPM literature by showing that the frequency of white coat hypertension is inversely related to the degree of hypertension, as determined from casual measurements. White coat hypertension was found in only 15% of patients with blood pressure 20% above normal levels, but was present in 52% of patients with blood pressure 10% above normal. They correctly conclude that ABPM does not add substantially to the accurate identification of children with moderate to severe hypertension. They also conclude that these data support the use of ABPM in children with mild hypertension, but the evidence for this is less convincing. Of the 71 patients in this study, 65% were males who were generally overweight (mean body mass index [BMI] ⫽ 28.5 kg/m2) and older than the females; this is the expected demographic picture in pediatric population studies for children at the higher percentiles of blood pressure distribution. Most clinicians would be reluctant to initiate pharmacologic treatment in children with mild hypertension, particularly without first attempting non-pharmacologic intervention emphasizing weight loss and exercise. Even if white coat hypertension is identified in this group, studies confirming
Received April 18, 2001. Accepted May 30, 2001. From the Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN.
Address correspondence and reprint requests to Alan Sinaiko, MD, University of Minnesota Medical School, Box 491, 420 Delaware Street SE, Minneapolis, MN 55455; e-mail: [email protected]
0895-7061/01/$20.00 PII S0895-7061(01)02199-9
© 2001 by the American Journal of Hypertension, Ltd. Published by Elsevier Science Inc.
AJH–September 2001–VOL. 14, NO. 9, PART 1
the significant correlation between childhood weight and BMI with adult cardiovascular risk factors10 dictate that these children should not be ignored and that weight control and exercise strategies should be initiated. Thus, based on the data from this study it is not clear how, at the present time, ABPM contributes significantly to the clinical management of childhood hypertension. Mean blood pressure is increasing in the childhood population,11 suggesting that larger numbers of children with mild to moderate hypertension will be identified in coming years. The strong tracking effect for blood pressure between childhood and adulthood and the significant relation between blood pressure and other cardiovascular risk factors in childhood is evidence enough to encourage ongoing intensive investigation into blood pressure-related issues during the first two decades. Critical to these studies is an ability to precisely measure blood pressure to obtain basic information about blood pressure patterns, to identify hypertensive individuals, and to develop blood pressure data in clinical studies. As shown in adult studies,12 ABPM has the potential to serve that role. If ABPM were easily available, easier to administer, and inexpensive, it would probably be more widely used in children and broader-based ABPM standards would have been established by now. However, this is not the case and more compelling evidence needs to be presented to justify the addition of ABPM to routine pediatric practice.
References 1.
Task Force on Blood Pressure Control in Children-1997: Pediatrics 1997;59:797– 820.
EDITORIAL
2.
977
Task Force on Blood Pressure Control in Children-1987: Report of the second task force on blood pressure control in children-1987. Pediatrics 1987;79:1–25. 3. Update on the Task Force (1987) on high blood pressure in children and adolescents. A working group from the National High Blood Pressure Education Program. Pediatrics 1996;98:649 – 658. 4. Adrogue HE, Sinaiko AR: Prevalence of hypertension in junior high school-aged children: effect of new recommendations in the 1996 updated task force report. Am J Hypertens 2001;14:412– 414. 5. Sorof JM, Poffenbarger T, Franco K, Portman R: Evaluation of white coat hypertension in children: importance of the definitions of “normal” ambulatory blood pressure and the severity of casual hypertension. Am J Hypertens 2001;14:855– 860. 6. Soergel M, Kirschstein M, Busch C, Danne T, Gellermann J, Holl R, Drull F, Reichert H, Reusz GS, Rascher W: Oscillometric twentyfour-hour ambulatory blood pressure values in healthy children and adolescents: a multicenter trial including 1141 subjects. J Pediatrics 1997;130:178–184. 7. Harshfield GA, Alpert BS, Pulliam DA, Somes GW, Wilson DK: Ambulatory blood pressure recordings in children and adolescents. Pediatrics 1994;94:180–184. 8. Lurbe E, Redin J, Liao Y, Tacons J, Cooper RS, Alvarez V: Ambulatory blood pressure monitoring in normotensive children. J Hypertens 1994;12:1417–1423. 9. Reichert H, Lindinger A, Frey O, Mortzeck J, Kiefer J, Busch C, Hoffman W: Ambulatory blood pressure monitoring in healthy school children. Pediatr Nephrol 1995;9:282–286. 10. Sinaiko AR, Donahue RP, Jacobs DR, Prineas RJ: Relation of rate of growth during childhood and adolescence to fasting insulin, lipids, and systolic blood pressure in young adults. Circulation 1999;99:1471–1476. 11. Luepker R, Prineas RJ, Jacobs DR, Sinaiko AR: Secular trends of blood pressure and body size in a multi-ethnic adolescent population: 1986 –1996. J Pediatrics 1999;134:668– 674. 12. Mallion JM, Baquet JP, Siche JP, Tremel F, DeGaudemaris R: Clinical value of ambulatory blood pressure monitoring. J Hypertens 1999;17:585–595.