Hypertension in Children and Adolescents – Diagnostic Challenges and Management


Table 1: Worldwide Prevalence of Abnormal Blood Pressure in Children Country/Region


Brazil Canada Greece


India Iran


Italy Seychelles South Africa South Asia


Taiwan US


Prevalence (%) 17.3 7.4


12.3–15.1


10.1 7.7


10.1 9.1–10.1 1–11.4 12.2


12.9 13.8


Setting School


Community School School


National survey School


School-based national survey School


National survey School School


Method


Office BP, first measurement Average of three BP readings on a single occasion


Mean value of the last two


measurements on a single occasion NA


Task Force 2004 Task Force 2004


Oscillometric, average of two readings on one occasion


Oscillometric, at least three readings


Auscultatory, average of two measurements on one occasion NA


Oscillometric, average of two measurements on one occasion


The results are from published population studies and presented by country/region in alphabetical order. BP = blood pressure; NA = not available. Reproduced with permission, from Feber and Ahmed, Clinical Science, 2010;119:151–61.59


The current method used to diagnose paediatric hypertension is based on percentiles. Hypertension and pre-hypertension are defined as an average systolic and/or diastolic blood pressure greater than or equal to the 95th percentile and the 90th percentile, respectively, for age, sex and height on at least three separate occasions.8,14


Blood


pressure is further categorised as stage I (95th–99th percentile plus 5 mmHg) and stage II hypertension (99th percentile plus 5 mmHg).8 Normative data vary in populations by nationality or ethnicity.16,17


This approach leads to many abnormal cut-offs according to age, gender and height, which may be difficult for physicians to remember and use in a busy clinical practice, as they need to consistently refer to standards and review patients’ previous blood pressure readings according to gender and height percentiles.10


This complexity has


and it may therefore be useful to explore options for modifying the diagnostic method. Some proposed methods include producing more simple cut-offs, simplifying the blood pressure tables for quick screening, and developing programmes using electronic patient records – including alerts.10,16


probably contributed to the underdiagnosis of paediatric hypertension,10,15


electronic records did not improve recognition;10


In one study, the use of however, the use


of alerts or reminders linked to electronic patient records may improve the recognition of high blood pressure. Other tools, such as paediatric blood pressure calculators built into iPhones® or BlackBerrys®, may also aid physicians to recognise hypertension in a timely and practical manner.


In Table 2, we propose simple cut-off points regardless of gender that would be easy to remember. For example, in boys or girls aged 3, the 90th percentile would be 100/60; aged 6, it would be 105/70; aged 14, it would be 120/75 and similar cut-offs by gender have also been proposed to aid in the diagnosis of hypertension.18


These new


thresholds would make it easier for the primary physician to screen for elevated blood pressure. If clinic blood pressure is elevated, the blood pressure needs to be checked manually and repeated.


EUROPEAN NEPHROLOGY © the Biochemical Society.


Other factors that may improve the diagnosis of hypertension include the use of appropriate cuff sizes and auscultation. Children and adolescents have different arm sizes and thus require different cuff sizes, given that using an unsuitably sized cuff may give false readings.19


Definition


Task Force 1996 Task Force 2004


Task Force 2004 NA Task Force 2004


Task Force 2004 Task Force 2004


Task Force 2004 Task Force 2004 NA Task Force 2004


Population Adolescents Age 4–17


Age 7–15 NA Age 6–18


Age 11–14 Age 5–16


Age 7–13 Age 5–14 NA Age 5–17


Often, the cuff size is chosen based on the child’s age, rather than the size of their upper arm; using cuffs that are too small will lead to falsely high blood pressure readings.


Furthermore, the ideal method of assessing blood pressure, though difficult in small children, is auscultation. Automated oscillometric instruments, which are frequently employed for convenience, overestimate blood pressure.20


Repeating blood pressure


If clinicians do use oscillometric


devices and find blood pressure measurements greater than the 90th percentile, it has been recommended that they repeat blood pressure measurement by auscultation.8


measurements manually three times in the course of a visit, or scheduling multiple clinic visits for the patient to have their blood pressure measured, facilitates the diagnosis of hypertension. Blood pressure should also be measured in a quiet setting, after the child has rested for at least five minutes, with both their feet flat on the ground and their back and right arm supported.8,21


It is often


difficult to conduct multiple blood pressure measurements in children; considering the use of a 24-hour ambulatory blood pressure monitor can be particularly helpful in children above the age of 8.8,21


Screening for Other Causes of Hypertension It is important to screen for secondary causes of hypertension, which are more often seen in children than in adults and tend to occur more commonly in younger children and in those with more severe hypertension; this requires a thorough work-up.20


Secondary causes of


hypertension can sometimes be treated, leading to a normalisation of blood pressure without the need for additional antihypertensive medication.8


Renal parenchymal disease accounts for approximately


75 % of all secondary causes of hypertension, while reno-vascular disease accounts for 10 %.20


Other less common secondary causes of 127


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92