Masked hypertension and allograft function in pediatric and young adults kidney transplant recipients

[Ambulatory blood pressure monitoring, adult and pediatric population. A narrative review]

Hypertension has become a central risk factor for the development of cardiovascular disease, underscoring the importance of its accurate diagnosis. Numerous studies have established a close relationship between elevated systolic (SBP) and diastolic (DBP) blood pressure and an increased risk of cardiovascular event (CVE). Traditionally, blood pressure (BP) measurements performed in clinical settings have been the main method for diagnosing and assessing hypertension. However, in recent years, it has been recognized that BP measurements obtained outside the clinical setting, using self-monitoring blood pressure (SMBP) and ambulatory blood pressure monitoring (ABPM), offer a more realistic perspective of patients' daily lives and therefore provide more reliable results. Given the evolution of medical devices, diagnostic criteria, and the increasing relevance of certain components of ABPM in the prediction of adverse cardiovascular outcomes, a comprehensive update that is practical for daily clinical practice is required. The main objective of this article is to provide an updated review of ABPM, focusing on its importance in the evaluation of hypertension and its impact on public health in Colombia. In addition, it will discuss the implications of changes in diagnostic thresholds and provide concrete recommendations for the effective implementation of ABPM in clinical practice, allowing health professionals to make informed decisions and improve the care of their patients.

Masked Hypertension in Healthy Children and Adolescents: Who Should Be Screened?

PURPOSE OF REVIEW

The goal is to review masked hypertension (MH) as a relatively new phenomenon when patients have normal office BP but elevated out-of-office BP. Firstly, it was described in children in 2004. It has received increased attention in the past decade.

RECENT FINDINGS

The prevalence of MH in different pediatric populations differs widely between 0 and 60% based on the population studied, definition of MH, or method of out-of-office BP measurement. The highest prevalence of MH has been demonstrated in children with chronic kidney disease (CKD), obesity, diabetes, and after heart transplantation. In healthy children but with risk factors for hypertension such as prematurity, overweight/obesity, diabetes, chronic kidney disease, or positive family history of hypertension, the prevalence of MH is 9%. In healthy children without risk factors for hypertension, the prevalence of MH is very low ranging 0-3%. In healthy children, only patients with the following clinical conditions should be screened for MH: high-normal/elevated office BP, positive family history of hypertension, and those referred for suspected hypertension who have normal office BP in the secondary/tertiary center.

The significance of central blood pressure for cardiovascular target organ damage in children and adolescents after kidney transplantation

BACKGROUND

Cardiovascular (CV) complications are important causes of morbidity and mortality in children after kidney transplantation (KTx). In adults, central blood pressure (cBP) is an accepted predictor of CV sequelae. We aimed to assess the prognostic value of cBP over peripheral blood pressure (pBP) for existing CV damage.

METHODS

We measured cBP and pBP in 48 pediatric KTx recipients (mean age: 13.5 ± 4.2 years). Assessment of left ventricular mass index (LVMI) and aortic pulse wave velocity (PWV) allowed detection of CV target organ damage. LVMI and PWV were used as endpoints in multivariable linear regression models, in which cBP and pBP were compared for their predictive value.

RESULTS

Using cBP z-scores, we identified a larger number of patients with uncontrolled or untreated hypertension compared to pBP (36% vs. 7%). Central systolic blood pressure (cSBP) was a significant independent predictor of LVMI, while peripheral systolic blood pressure (pSBP) was not. Comparing central (cDBP) and peripheral (pDBP) diastolic blood pressure for their predictive value on PWV revealed a greater estimate for cDBP (0.035 vs. 0.026 for pDBP) along with a slightly better model fit for cDBP.

CONCLUSIONS

Our data in a small group of patients provide first evidence that cBP measurements in pediatric KTx recipients might be helpful in identifying patients at risk for the development of CV sequelae. Investigating a larger patient number, ideally repeatedly, is needed to create further evidence supporting our findings. In light of available devices measuring cBP noninvasively, the implementation of such clinical studies post-KTx care should be feasible. A higher resolution version of the Graphical abstract is available as Supplementary information.

Prevalence of masked hypertension and its association with left ventricular hypertrophy in children and young adults with chronic kidney disease: a systematic review and meta-analysis

OBJECTIVES

There are limited studies using ambulatory blood pressure monitoring (ABPM) to assess blood pressure (BP) status in young patients with chronic kidney disease (CKD) on dialysis or after kidney transplantation. The aim of this meta-analysis is to estimate the prevalence of both white-coat hypertension (WCH) and masked hypertension, along with the prevalence of left ventricular hypertrophy (LVH), in children and young adults with CKD on dialysis or after kidney transplantation.

METHODS

We performed a systematic review and meta-analysis of observational studies assessing the prevalence of BP phenotypes using ABPM, in children and young adults with CKD stages 2-5d. Records were identified by search in databases (Medline, Web of Science, CENTRAL) and sources of grey literature, until 31 December 2021. A random-effects meta-analysis of proportions (double arcsine transformation) was conducted.

RESULTS

Ten studies were included in the systematic review, reporting data from 1140 individuals (children and young adults with CKD with a mean age of 13.79 ± 4.35 years). Masked hypertension and WCH were diagnosed in 301 and 76 patients, respectively. It was estimated an overall pooled masked hypertension prevalence of 27% [95% confidence interval (95% CI) 18-36, I2  = 87%] and an overall pooled WCH prevalence of 6% (95% CI 3-9, I2  = 78%). Among kidney transplant recipients, masked hypertension had a prevalence of 29% (95% CI 14-47, I2  = 86%). The prevalence of LVH was found 28% (95% CI 0.19-0.39) in a total of 238 CKD patients with ambulatory hypertension. In 172 CKD patients with masked hypertension, LVH was present in 49, with the estimated prevalence being 23% (95% CI 0.15-0.32).

CONCLUSION

Masked hypertension has a significant prevalence in children and young adults with CKD. Masked hypertension carries an adverse prognosis, with an increased risk of LVH, warranting clinical attention when assessing cardiovascular risk in this population. Therefore, ABPM and echocardiography is of high importance when assessing BP status in children with CKD.

PROTOCOL REGISTRATION NUMBER DOI

10.17605/OSF.IO/UKXAF.

Ambulatory Blood Pressure Monitoring in Pediatrics, an Update on Interpretation and Classification of Hypertension Phenotypes

PURPOSE OF REVIEW

This review highlights the major changes reflected in the 2022 American Heart Association (AHA) Scientific Statement on Ambulatory Blood Pressure Monitoring (ABPM) in Children and Adolescents with a specific focus on the newly defined phenotypes of hypertension and their epidemiology and associated outcomes.

RECENT FINDINGS

The 2022 AHA guidelines' most notable changes include the following: (1) alignment of blood pressure (BP) thresholds with the 2017 American Academy of Pediatrics (AAP) clinical practice guidelines, 2017 American College of Cardiology (ACC)/AHA hypertension guidelines, and 2016 European Society of Hypertension (ESH) pediatric recommendations; (2) expansion of the use of ABPM to diagnose and phenotype pediatric hypertension in all pediatric patients; (3) removal of BP loads from diagnostic criteria; and (4) simplified classification of new hypertension phenotypes to prognosticate risks and guide clinical management. Recent studies suggest that utilizing the 2022 AHA pediatric ABPM guidelines will increase the prevalence of pediatric ambulatory hypertension, especially for wake ambulatory hypertension in older, taller males and for nocturnal hypertension in both males and females ≥ 8 years of age. The new definitions simplify the ambulatory hypertension criteria to include only the elements most predictive of future health outcomes, increase the sensitivity of BP thresholds in alignment with recent data and other guidelines, and thus make hypertension diagnoses more clinically meaningful. This guideline will also aid in the transition of adolescents and young adults to adult medical care. Further studies will be necessary to study ambulatory BP norms in a more diverse pediatric population and evaluate the impact of these guidelines on prevalence and future outcomes.

Ambulatory Blood Pressure Monitoring in Children and Adolescents: 2022 Update: A Scientific Statement From the American Heart Association

Use of ambulatory blood pressure monitoring in children and adolescents has markedly increased since publication of the last American Heart Association scientific statement on pediatric ambulatory blood pressure monitoring in 2014. In addition, there has also been significant expansion of the evidence base for use of ambulatory blood pressure monitoring in the pediatric population, including new data linking ambulatory blood pressure levels with the development of blood pressure-related target organ damage. Last, additional data have recently been published that enable simplification of the classification of pediatric ambulatory monitoring studies. This scientific statement presents a succinct review of this new evidence, guidance on optimal application of ambulatory blood pressure monitoring in the clinical setting, and an updated classification scheme for the interpretation of ambulatory blood pressure monitoring in children and adolescents. We also highlight areas of uncertainty where additional research is needed.

Plasma Netrin-1 & cardiovascular risk in children with end stage renal disease

Background: Cardiovascular disease (CVD) is the most common cause of mortality and morbidity in children with end stage kidney disease (ESKD) which arises from the interaction of several risk factors. The aim of the study is to assess CV risk of ESKD children and outline the impact of KTX on this CV risk. Also valuate the relation between plasma Netrin-1, chronic inflammatory markers and CV risk. Methods: Sixty ESKD (30 on regular hemodialysis (HD), 30 recipients of kidney transplant (KTX)) were assessed using 24 hour AMBP assessment, laboratory (including lipid profile and markers of chronic inflammation namely N/L and HsCRP) and echocardiographic data. Plasma netrin-1 was assessed by ELISA technique for all patients. Results: showed significant higher prevalence of hypertension, higher number of patients with 24hrs BP> 95th percentile by ABPM, more prevalence of nocturnal non-dipping BP, higher percentage of obese and overweight patients, worse biochemical analysis, higher chance of medical calcification by higher Po4 and Ca X Po4, higher triglyceride level and lower HDL level and higher N/L in HD than KTX group. Significant inverse relation was detected between plasma netrin 1 and Hs CRP and between netrin 1 and N/L (p<0.001).

Isolated nocturnal hypertension in pediatric kidney transplant recipients

BACKGROUND

Isolated nocturnal hypertension (INH) is defined as nighttime hypertension in the setting of normal daytime blood pressure (BP), diagnosed by ambulatory BP monitoring (ABPM).

METHODS AND RESULTS

Hypertension affects 60%-80% of pediatric kidney transplant recipients, and INH is the most common type of ambulatory hypertension. INH is associated with an increased prevalence of hypertension-mediated target organ damage such as left ventricular hypertrophy in adults and in pediatric kidney transplant recipients.

CONCLUSION

Ambulatory BP monitoring should be performed annually in all pediatric kidney transplant recipients to diagnose hypertension phenotypes that are not detectable by office BP such as masked hypertension, white-coat hypertension, or INH. Isolated nocturnal hypertension in pediatric transplant patients requires study as a treatment target.

Pediatric kidney transplant and cardiometabolic risk: a cohort study

INTRODUCTION

Patients with chronic kidney disease (CKD) are known to have increased cardiovascular risk but there are few data on the risk of pediatric kidney transplant recipients. We aimed to assess the impact of pre- and post-transplant overweight on allograft function and to characterize the evolution of several cardiovascular risk variables over time and their impact.

METHODS

A retrospective analysis of the records of 23 children/adolescents followed at a tertiary center after kidney transplant was conducted. Data on anthropometry and cardiometabolic variables were analyzed before transplant, six and 12 months after the transplant, and at the last follow-up visit. The impact of the variables on allograft function (glomerular filtration rate (GFR)) was estimated by creatinine-based revised Schwartz formula (Cr-eGFR) and was evaluated using nonparametric tests. Results: The 23 patients included in the study had a median age of 6.3 (4.4-10.1) years. Both systolic and diastolic BP z-score values significantly decreased between BMI groups [1.2 (-0.2 - 2.3) vs. 0.3 (-0.4 - 0.6), p=0.027 and 0.8 (-0.4 - 1.3) vs. 0.1 (-0.6 - 0.7), p=0.028, pre-transplant and at the final evaluation, respectively]. During follow-up, GFR values decreased (Cr-GFR: 68.9 (57.7-76.8) vs. 58.6 (48.9-72.9), p=0.033 at 6-months and at the end, respectively). Significant negative correlations between triglycerides and cystatin C-based eGFR (ρ=-0.47, p=0.028) and Cr-Cys-eGFR (ρ=-0.45, p=0.043) at the end of the study were found.

CONCLUSION

Our study showed a high number of overweight children undergoing kidney transplant. A negative correlation between triglycerides and GFR was found, which highlights the importance of managing nutritional status and regular blood lipids evaluation after kidney transplant.

Clinical Innovation: A Multidisciplinary Program for the Diagnosis and Treatment of Systemic Hypertension in Children and Adolescents

Pediatric systemic hypertension (HTN) is underdiagnosed and undertreated. The Divisions of Cardiology and Nephrology at our institution developed a comprehensive outpatient HTN program to (1) screen children at risk for HTN, (2) assess cardiovascular health, and (3) optimize medical management. We report our findings during all initial visits (n = 304) from December 2011 to September 2018. Of the cohort, 38% were obese and 36% reported little to no exercise. More than half of patients ≥11 years old did not have recommended lipid screening. When evaluating ambulatory blood pressure monitoring results, clinic blood pressure did not accurately diagnose patients with or without HTN and many patients on antihypertensive medications were inadequately treated. Visit recommendations included addition of or changes to antihypertensive medication in 35% of patients. A multidisciplinary program dedicated to pediatric HTN helps screen patients who are at risk. Ambulatory blood pressure monitoring identifies HTN in patients with normal clinic blood pressure and those on antihypertensive medication.

Clinical value of ambulatory blood pressure in pediatric patients after renal transplantation

Hypertension is a highly prevalent co-morbidity in pediatric kidney transplant recipients. Undertreated hypertension is associated with cardiovascular complications and negatively impacts renal graft survival. Thus, the accurate measurement of blood pressure is of the utmost importance for the correct diagnosis and subsequent management of post-renal transplant hypertension. Data derived from the general population, and to a lesser extent from the pediatric population, indicates that ambulatory blood pressure monitoring (ABPM) is superior to blood pressure measurements taken in the clinical setting for the evaluation of true mean blood pressure, identification of patients requiring antihypertensive treatment, and in the prediction of cardiovascular outcome. This Educational Review will discuss the clinical value of ABPM in the identification of individual blood pressure phenotypes, i.e., normotension, new-onset hypertension, white-coat hypertension, masked hypertension, controlled blood pressure, and undertreated/uncontrolled hypertension in pediatric kidney transplant recipients. Finally, we examine the utility of performing repeated ABPM for treatment monitoring of post-renal transplant hypertension and on surrogate markers related to relevant clinical cardiovascular outcomes. Taken together, our review highlights the clinical value of the routine use of ABPM as a tool for identifying and monitoring hypertension in pediatric kidney transplant recipients.

Is Blood Pressure Improving in Children With Chronic Kidney Disease? A Period Analysis

Uncontrolled hypertension in children with chronic kidney disease (CKD) has been identified as one of the main factors contributing to progression of CKD and increased risk for cardiovascular disease. Recent efforts to achieve better blood pressure (BP) control have been recommended. The primary objective of this analysis was to compare BP control over 2 time periods among participants enrolled in the CKiD study (Chronic Kidney Disease in Children). Casual BP and 24-hour ambulatory BP monitor data were compared among 851 participants during 2 time periods: January 1, 2005, through July 1, 2008 (period 1, n=345), and July 1, 2010, through December 31, 2013 (period 2, n=506). Multivariable logistic regression to model the propensity of a visit record being in period 2 as a function of specific predictors was performed. After controlling for confounding variables (age, sex, race, socioeconomics, CKD duration, glomerular filtration rate, proteinuria, body mass index, growth failure, and antihypertensives), no significant differences were detected between time periods with respect to casual BP status (prehypertension: 15% versus 15%; uncontrolled hypertension: 18% versus 17%; P=0.87). Analysis of ambulatory BP monitor data demonstrated higher ambulatory BP indices, most notably masked hypertension in period 2 (36% versus 49%; P<0.001). Average sleep BP index (P<0.05) and sleep BP loads (P<0.05) were higher in period 2. Despite publication of hypertension recommendations and guidelines for BP control in patients with CKD, this study suggests that hypertension remains undertreated and under-recognized in children with CKD. This analysis also underscores the importance of routine ambulatory BP monitor assessment in children with CKD.

Hypertension in the Pediatric Kidney Transplant Recipient

Hypertension after kidney transplant is a frequent occurrence in pediatric patients. It is a risk factor for graft loss and contributes to the significant burden of cardiovascular disease (CVD) in this population. The etiology of posttransplant hypertension is multifactorial including donor factors, recipient factors, medications, and lifestyle factors similar to those prevalent in the general population. Ambulatory blood pressure monitoring has emerged as the most reliable method for measuring hypertension in pediatric transplant recipients, and many consider it to be essential in the care of these patients. Recent technological advances including measurement of carotid intima-media thickness, pulse wave velocity, and myocardial strain using specked echocardiography and cardiac magnetic resonance imaging have improved our ability to assess CVD burden. Since hypertension remains underrecognized and inadequately treated, an early diagnosis and an appropriate control should be the focus of therapy to help improve patient and graft survival.