CLINICAL METHODS AND PATHOPHYSIOLOGY Impact of ambulatory blood pressure monitoring on the management of hypertension in children Joseph T. Flynn Background Ambulatory blood pressure monitoring ( ) ABPM is widely utilized for the evaluation and management of hypertension in adults but has not been routinely used in the care of hypertensive children. Design To examine the potential impact that the routine use of ABPM might have on the evaluation and management of hypertension in children, we reviewed our early experience with this technique, comparing management decisions based on ABPM with those based on casual blood pressure readings. ( ) Methods Twenty children 4–17 years old underwent ABPM for either the initial evaluation of suspected hypertension or the ongoing management of known hypertension. ABPM studies were considered abnormal if over 40% of both systolic and/ or diastolic blood pressure readings were above the 95th percentile for the child’s age and gender. Results Of 13 children studied for suspected hypertension, nine had abnormal ABPM studies and were treated, but four had normal results and were therefore not treated. Of seven children with known hypertension studied by ABPM to assess their blood pressure control further, three had normal results and no management changes were made, but four had abnormal studies, prompting a change in therapy or further diagnostic testing. Overall, eight out of 20 ABPM studies led to the initiation of further diagnostic evaluation or a change in planned or ongoing therapy. Conclusions We conclude that ABPM has the potential to become an important tool in the evaluation and management of childhood hypertension, and suggest that more widespread use of this technique in children is appropriate. Blood Press Monit 5:211–216  2000 Lippincott Williams & Wilkins. Blood Pressure Monitoring 2000, 5:211–216 Keywords: ambulatory blood pressure monitoring, childhood hypertension, medical decision-making Division of Pediatric Nephrology, Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI, USA. Presented in abstract form at the American Society of Hypertension Annual Meeting, San Francisco, CA, USA, May 1997. Conflict of interest: None. Correspondence and requests for reprints to Joseph T. Flynn, MD, Pediatric Nephrology, Mott F6865 – Box 029, 71505 Simpson Road East, Ann Arbor, MI 48109, USA. Tel: +1 734 936 4210; fax: +1 734 763 6997; e-mail: jtflynn@umich.edu Received 09 March 2000 Revised 16 June 2000 Accepted 21 June 2000 Introduction The detection and management of hypertension in any patient depends on accurate blood pressure measure- ment. Traditionally, the evaluation of hypertension in children has relied upon casual blood pressures ob- tained by manual or automated devices in the clinic or home setting. However, blood pressures obtained by these methods may not accurately reflect a child’s true  blood pressure, because of either operator error 1 , the  inaccurate reporting of results 2 , device inaccuracies   1,3 , or simply the known tendency of children’s blood  pressure to fluctuate widely over time 4 . Ž . Ambulatory blood pressure monitoring ABPM is a relatively new technique in which a subject’s blood pressure can be measured at regular intervals over a 24   h period 1,5 . Devices have been developed that are   well tolerated by adults 1 and children 4 alike. ABPM has gained widespread acceptance as a diagnostic and monitoring technique in adults with hypertension, and has been used to predict the development of end-organ damage and other hypertension-associated morbidity   1,5,6 , and to assess the efficacy of antihypertensive   medications 5,7,8 . Although ABPM could be ex- tremely useful in the diagnosis and management of childhood hypertension, it has not gained widespread   acceptance 5,9 , primarily because of a lack of experi- ence with this technique in children. The purpose of this study was to determine the potential impact of routine use of ABPM in children on the diagnosis and management of childhood hypertension. Methods This study consisted of a retrospective review of ABPM studies performed for the evaluation of children with known or suspected hypertension. An analysis of ABPM data was conducted following the completion of the patients’ clinic visits and after any diagnostic or man- agement decisions had been made. ABPM studies were carried out over a standard 24 h period. The first 10 children were studied with the 1359-5237  2000 Lippincott Williams & Wilkins