The choice of threshold limits for pediatric ambulatory blood pressure monitoring influences clinical decisions

Pediatric ambulatory blood pressure monitoring: indications and interpretations

The prevalence of hypertension in children and adolescents is increasing, especially in obese and ethnic children. The adverse long-term effects of hypertension beginning in youth are known; therefore, it is important to identify young patients who need intervention. Unfortunately, measuring blood pressure (BP) is difficult due to the variety of techniques available and innate biologic variation in BP levels. Ambulatory BP monitoring may overcome some of the challenges clinicians face when attempting to categorize a young patient's BP levels. In this article, the authors review the use of ambulatory BP monitoring in pediatrics, discuss interpretation of ambulatory BP monitoring, and discuss gaps in knowledge in usage of this technique in the management of pediatric hypertension.

Comparison of ambulatory blood pressure reference standards in children evaluated for hypertension

OBJECTIVE

The purpose of this study was to systematically compare methods for standardization of blood pressure levels obtained by ambulatory blood pressure monitoring (ABPM) in a group of 111 children studied at our institution.

METHODS

Blood pressure indices, blood pressure loads and standard deviation scores were calculated using the original ABPM and the modified reference standards. Bland-Altman plots and kappa statistics for the level of agreement were generated.

RESULTS

Overall, the agreement between the two methods was excellent; however, approximately 5% of children were classified differently by one as compared with the other method.

CONCLUSION

Depending on which version of the German Working Group's reference standards is used for interpretation of ABPM data, the classification of the individual as having hypertension or normal blood pressure may vary.

Cost-effectiveness of ambulatory blood pressure monitoring in the initial evaluation of hypertension in children

OBJECTIVE

The goal was to determine the cost-effectiveness of ambulatory blood pressure monitoring in the initial evaluation of stage 1 hypertension.

METHODS

Retrospective chart review of data for children referred to Texas Children's Hospital hypertension clinic between January 2005 and August 2006 was performed. We compared the costs of standard evaluations versus the initial use of ambulatory blood pressure monitoring for children with clinic blood pressure measurements suggesting stage 1 hypertension. Charges for clinic visits, laboratory tests, and imaging were obtained from the Texas Children's Hospital billing department.

RESULTS

A total of 267 children were referred. One hundred thirty-nine children did not receive ambulatory blood pressure monitoring; 54 met clinical indications for ambulatory blood pressure monitoring but did not receive it because it was not a covered expense (44 children) or the family refused the study (10 children). One hundred twenty-six children received clinically indicated ambulatory blood pressure monitoring, paid for either through insurance or by the family. Fifty-eight children (46%) had confirmed white-coat hypertension, 62 (49%) stage 1 hypertension, and 6 (5%) stage 2 hypertension. With the observed prevalence of white-coat hypertension, initial ambulatory blood pressure monitoring use yielded net savings after evaluation of 3 patients, with projected savings of $2.4 million per 1000 patients.

CONCLUSIONS

Ambulatory blood pressure monitoring in the initial evaluation of suspected childhood hypertension is highly cost-effective. Awareness of cost saving potential may increase the availability of ambulatory blood pressure monitoring for evaluation of new-onset hypertension.

Ambulatory blood pressure monitoring: a versatile tool for evaluating and managing hypertension in children

In recent years, pediatric practitioners have increasingly used ambulatory blood pressure (ABP) monitoring for evaluating blood pressure (BP) abnormalities in children. ABP monitoring in adults is superior to casual BP measurements for predicting cardiovascular morbidity and mortality, and whereas the association with target-organ damage in children is not as definitive, early evidence does seem to parallel the adult data. In addition to confirming hypertension at diagnosis, ABP monitoring may be useful for identifying isolated nocturnal hypertension, characterizing BP patterns, and assessing response to therapeutic interventions. This article reviews current evidence supporting the use of ABP monitoring in children and discusses limitations in our understanding of this technology, specifically focusing on indications for its use and interpretation of the large quantity of data obtained by ABP monitoring.

Management of systemic hypertension in children and adolescents: An update

Identification and treatment of hypertension should be an important focus of physicians caring for children. Ultimately, a link between hypertension in children and the risk of cardiovascular disease will be established. Further long-term studies are likely to show that morbidity and mortality will be decreased by the institution of treatment of hypertension in children. Additional risk factors such as obesity and lipid disorders should be sought and targeted for treatment as well. Lifestyle modifications are advised for all patients and can be tried solely for those with blood pressures between the 95th and 99th percentiles. Drug therapy is indicated in children with blood pressures greater than the 99th percentile, secondary hypertension, coexisting diabetes, left ventricular hypertrophy, or those who fail a trial of nonpharmacologic treatment. Children with white coat hypertension should not be treated with drugs. Children with renal artery stenosis and drug-refractory hypertension should be considered for percutaneous angioplasty or surgery depending on the anatomy of the lesion and operator experience. Children requiring multiple drug classes for control of blood pressure and older adolescents on one drug with renal artery lesions amenable to a percutaneous procedure may elect intervention in an attempt to reduce or eliminate drug therapy. Infants and children with hypertension due to native coarctation of the aorta should undergo surgical repair. Older children and adolescents with native coarctation should have surgical repair or percutaneous angioplasty/stenting. Hypertension secondary to recurrent coarctation is usually treated with a percutaneous intervention.

Ambulatory blood pressure monitoring and target organ damage in pediatrics

The prevalence of hypertension in children and adolescents is rising in association with the increasing rate of childhood obesity, and it is associated with early target organ damage. Published guidelines on high blood pressure in children and adolescents, focused on the early and accurate diagnosis of hypertension, resulted in improved ability to identify children with hypertension. Although auscultation using a mercury sphygmomanometer remains the method of choice for evaluation of hypertension in children, accumulating evidence suggests that ambulatory blood pressure monitoring is a more accurate method for diagnosis, and it is more closely associated with target organ damage. In addition, ambulatory blood pressure monitoring is a valuable tool in the assessment of white-coat hypertension, and masked hypertension in children and adolescents. Masked hypertension in children and adolescents is associated with a similar risk of target organ damage as in established hypertension.

Ambulatory blood pressure monitoring: what a pediatrician should know

PURPOSE OF REVIEW

Ambulatory blood pressure monitoring is a useful tool for the evaluation and management of hypertension in children and adolescents. This review provides a basic overview of ambulatory blood pressure monitoring and summarizes the most recent available knowledge regarding its use in the pediatric population.

RECENT FINDINGS

Evaluation and validation of ambulatory blood pressure monitoring equipment in children remains limited, although advances in the interpretation of results for this age group have been reported specifically in the area of circadian (24 h) and ultradian (<24 h) variability. Blood pressure is a dynamic phenomenon that varies not only with time but also with changing patient and environmental circumstances. Growing evidence regarding conditions identified when this variability is considered, specifically white coat and masked hypertension, suggests that office blood pressure measurement may not be a sufficient screening test for hypertension-related target-organ damage.

SUMMARY

Information regarding ambulatory blood pressure monitoring use in children is increasing, although due to its limitations and expense, it remains a tool primarily utilized by the pediatric sub-specialist.