Publications by authors named "Ronald J Portman"

In November 2014, the American Academy of Pediatrics convened key stakeholders to discuss the feasibility of accelerating children's medical advances by creating an independent global Pediatric Clinical Trials Network. The Forum identified challenges posed by the U.S.

View Article and Find Full Text PDF

The aim of the study was to determine the presence of preclinical diastolic dysfunction in hypertensive children relative to normotensive children by Tissue Doppler Imaging (TDI). We prospectively enrolled children with untreated essential hypertension in absence of any other disease and a matched healthy control group with normal blood pressure (BP); both groups confirmed by clinic BP and a 24-hour ambulatory BP monitoring. Echocardiographic diastolic parameters were determined using spectral transmitral inflow Doppler, flow propagation velocity, TDI, and systolic parameters were determined via midwall shortening fraction and ejection fraction.

View Article and Find Full Text PDF

Study Objective: To evaluate the accuracy of four equations based on serum creatinine concentration-the original Schwartz equation and the Leger, Bedside Chronic Kidney Disease in Children (CKiD), and Counahan-Barratt equations-for determining glomerular filtration rate (GFR) in pediatric patients with chronic kidney disease.

Design: Retrospective, observational, cross-sectional study.

Setting: Single-center, academic, outpatient pediatric nephrology clinic.

View Article and Find Full Text PDF

Objective: To measure the prevalence of persistent prehypertension in adolescents.

Study Design: We collected demographic and anthropometric data and 4 oscillometric blood pressure (BP) measurements on 1020 students. The mean of the second, third, and fourth BP measurements determined each student's BP status per visit, with up to 3 total visits.

View Article and Find Full Text PDF

Objective: To evaluate the risk for developing incident hypertension (HTN) in adolescents with pre-hypertension.

Study Design: A secondary analysis of students participating in multiple school-based blood pressure (BP) screens from 2000 to 2007 was completed. At each screen, height, weight, and 2 to 4 BPs were measured on as many as 3 occasions when BP remained ≥ 95th percentile.

View Article and Find Full Text PDF

Background: The optimal strategy for thromboprophylaxis after major joint replacement has not been established. Low-molecular-weight heparins such as enoxaparin predominantly target factor Xa but to some extent also inhibit thrombin. Apixaban, a specific factor Xa inhibitor, may provide effective thromboprophylaxis with a low risk of bleeding and improved ease of use.

View Article and Find Full Text PDF

The National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents recently recommended staging hypertension (HTN) in children and adolescents based on blood pressure severity. The use of blood pressure staging and its corresponding therapeutic approach was examined in this pooled analysis assessing the risk for end-organ damage, specifically left ventricular hypertrophy among hypertensive adolescents stratified by working group criteria. Newly diagnosed hypertensive adolescents and normotensive control subjects similar in age, race/ethnicity, gender, and body mass index completed casual and 24-hour ambulatory blood pressure measurements, M-mode echocardiography, and fasting serum laboratories.

View Article and Find Full Text PDF

Objective: To determine the prevalence of hypertension and pre-hypertension on the basis of the 2004 National High Blood Pressure Education Program Working Group guidelines in an adolescent school-screening population.

Study Design: Cross-sectional assessment of blood pressure (BP) in 6790 adolescents (11-17 years) in Houston schools was conducted from 2003 to 2005. Initial measurements included height, weight, and 4 oscillometric BP readings.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

Objective: To evaluate the efficacy, tolerability, and blood pressure (BP) lowering effect of extended release metoprolol succinate (ER metoprolol) in children 6 to 16 years of age with established hypertension.

Study Design: Patients were randomized to one of four treatment arms: placebo or ER metoprolol (0.2 mg/kg, 1.

View Article and Find Full Text PDF

A population pharmacokinetic study was conducted in 74 hypertensive children (mean age 10.4 +/- 4.4 years [mean +/- SD]) receiving amlodipine (mean dose 0.

View Article and Find Full Text PDF

Objectives: Evaluation of the efficacy and safety of amlodipine in hypertensive children.

Study Design: A randomized, double blinded, placebo-controlled, parallel-group, dose-ranging study was conducted at 49 centers in North and South America. The primary end point was the effect of amlodipine on systolic blood pressure (BP); secondary end points included the effect of amlodipine on diastolic BP, the effect of amlodipine as a function of dose and body size, and evaluation of safety.

View Article and Find Full Text PDF

Hypertension, as in adults, is a frequent complication found in children with chronic kidney disease (CKD). Indeed, hypertension has now become one of the most prevalent chronic diseases of childhood. The most recent data available (2003) indicate that at least 38% of children with CKD in the United States are receiving antihypertensive therapy.

View Article and Find Full Text PDF

Objectives: To determine whether there are clinical differences between children referred for hypertension evaluation from a primary care practice and children with hypertension detected through school-based screening. Study design Referral patients (n=58) were compared with 44 screening patients with hypertension from school-based screening of 5102 students. All subjects underwent 24-hour ambulatory blood pressure (BP) monitoring.

View Article and Find Full Text PDF

Objectives: To describe the current prevalence of pediatric hypertension and the relationships between gender, ethnicity, overweight, and blood pressure.

Methods: School-based screening was performed in 5102 children (13.5 +/- 1.

View Article and Find Full Text PDF

To determine whether systematic differences exist between hypertensive children referred for evaluation by primary care providers and children identified through community-based screening, cardiovascular risk factors and surrogate markers of hypertensive injury were compared based on subject source (referral versus screening). Children referred to a hypertension clinic for persistently elevated blood pressure were compared with children identified as hypertensive during school screening of 5102 students in Houston public schools. M-mode echocardiography of the left ventricle was performed and subsequently reviewed by 2 independent sonographers blinded to identifying subject information.

View Article and Find Full Text PDF

To determine whether hypertension and overweight status are associated with increased carotid intimal-medial thickness (cIMT) in children, vascular ultrasonography was performed in newly diagnosed hypertensive patients ( n=53) and normotensive controls ( n=33). Hypertensive subjects were identified either by referral or by systematic school-based hypertension screening. Hypertension was defined as blood pressure above the 95th percentile based on current Task Force criteria, and overweight was defined as body mass index (BMI) >25 kg/m(2).

View Article and Find Full Text PDF

Over last two decades ABPM has evolved from a research device to an established and valuable clinical tool for BP evaluation. More than 10 yrs ago ABPM was introduced to pediatrics and since that time, its importance has been increasing in the management of hypertension in children and adolescents. This review summarizes the information gathered from the studies of ABPM in adult and pediatric patients with renal transplants.

View Article and Find Full Text PDF