Treatment of systemic hypertension in children and adolescents

Race, obesity, and the renin-angiotensin-aldosterone system: treatment response in children with primary hypertension

BACKGROUND

Pediatric primary hypertension (HTN) is increasingly recognized, but the effect of patient characteristics such as obesity and race on treatment outcomes is not well described. The renin-angiotensin-aldosterone system (RAAS) may also contribute to HTN. We hypothesized patient parameters of these factors, including baseline RAAS, influence blood pressure (BP) response to pharmacological treatment in HTN.

METHODS

This was a retrospective cohort of 102 consecutive patients with HTN. Primary outcomes were changes per year in systolic and diastolic BP (SBP, DBP). Secondary outcome was change per year in left ventricular mass index (LVMI). We evaluated whether baseline plasma renin activity (PRA), aldosterone, renin-to-aldosterone ratio, overweight/obesity, race, initial drug choice, and multidrug therapy were associated with the outcomes using general linear regression models adjusted for confounding variables.

RESULTS

Racially diverse (43% Hispanic, 28% black, 25% white) and predominantly overweight/obese (75%) patients were studied. Median length of follow-up was 14.5 months. Higher baseline aldosterone was associated with decreased SBP (-1.03 mmHg/year), DBP (-0.95 mmHg/year), and DBP z score (-0.07/year) during the study period. Higher baseline PRA was associated with decreased SBP z score (-0.04/year) and LVMI (-2.89 g/m^2.7/year). Stratified analyses revealed the relationships between baseline aldosterone and PRA, and annual reductions in outcomes were strengthened in nonobese and white patients.

CONCLUSIONS

Pretreatment aldosterone and PRA predicted short-term follow-up BP and LVMI, especially in nonobese and white patients. The RAAS profile could guide treatment of HTN and suggests consideration of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers as first-line treatment options.

Propranolol 0.1% eye micro-drops in newborns with retinopathy of prematurity: a pilot clinical trial

BACKGROUND

Oral propranolol reduces retinopathy of prematurity (ROP) progression, although not safely. This study evaluated safety and efficacy of propranolol eye micro-drops in preterm newborns with ROP.

METHODS

A multicenter open-label trial, planned according to the Simon optimal two-stage design, was performed to analyze safety and efficacy of propranolol micro-drops in newborns with stage 2 ROP. To this end, hemodynamic and respiratory parameters were monitored, and blood samples were collected weekly, for 3 wk. Propranolol plasma levels were also monitored. The progression of the disease was evaluated with serial ophthalmologic examinations.

RESULTS

Twenty-three newborns were enrolled. Since the fourth of the first 19 newborns enrolled in the first stage of the study showed a progression to stage 2 or 3 with plus, the second stage was prematurely discontinued. Even though the objective to complete the second stage was not achieved, the percentage of ROP progression (26%) was similar to that obtained previously with oral propranolol administration. However, no adverse effects were observed and propranolol plasma levels were significantly lower than those measured after oral administration.

CONCLUSION

Propranolol 0.1% eye micro-drops are well tolerated, but not sufficiently effective. Further studies are required to identify the optimal dose and administration schedule.

Novel carvedilol paediatric nanomicelle formulation: in-vitro characterization and in-vivo evaluation

Objectives

Carvedilol (CAR) is a poorly water-soluble beta-blocker. Its encapsulation within nanomicelles (NMs) could improve drug solubility and its oral bioavailability, allowing the development of a paediatric liquid CAR formulation with commercially available copolymers: D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) and poly(vinyl caprolactam)-poly(vinyl acetate)-poly(ethylene glycol) (Soluplus®).

Methods

Drug-loaded NMs were prepared by copolymer and CAR dispersion in distilled water. Micellar size and morphology were characterized by dynamic light scattering and transmission electron microscopy, respectively. In-vitro drug permeation studies were evaluated by conventional gut sac method. In-vivo CAR oral bioavailability from NMs dispersions and drug control solution was evaluated in Wistar rats.

Key findings

Carvedilol apparent aqueous solubility was increased (up to 60.4-folds) after its encapsulation within NMs. The micellar size was ranged between 10.9 and 81.9 nm with a monomodal size distribution. There was a significant enhancement of CAR relative oral bioavailability for both copolymers vs a micelle-free drug solution (P < 0.05). This improvement was higher for TPGS-based micelles (4.95-fold) in accordance with the in-vitro CAR permeation results.

Conclusions

The present investigation demonstrates the development of highly concentrated CAR liquid micellar formulation. The improvement on drug oral bioavailability contributes to the potential of this NMs formulation to enhance CAR paediatric treatment.

Treatment of infantile haemangiomas: recommendations of a European expert group

With a prevalence of 2.6-4.5 %, infantile haemangiomas (IH) represent the most common tumour of infancy. While the majority of IH does not require therapy and regresses spontaneously, about 10 % of IH exhibit complications such as obstruction, ulceration or disfigurement. With the advent of oral propranolol, many conventional treatment options have become obsolete. This paper summarizes current recommendations for management of complicated IH. These recommendations have been written by an expert group after a consensus process including bibliographic review, several drafts of synthesis, meetings with quantitative voting system and redaction of an approved final manuscript.

CONCLUSION

Oral propranolol is the first-line agent for the treatment of complicated IH.

WHAT IS KNOWN

• Infantile haemangiomas (IH) are the most common tumours of infancy. Within a very short period after its discovery and long before the publication of randomized controlled trials, propranolol has become the number one agent for the treatment of complicated IH. What is New: • We report IH treatment recommendations of an international, interdisciplinary team of experts, based on an up-to-date review of the literature.

Ultrasound in assessing the efficacy of propranolol therapy for infantile hemangiomas

This study was aimed at assessing the efficacy of propranolol treatment in infantile hemangiomas (IHs) by ultrasound. Thirty-one patients with IHs were administered propranolol and were assessed by ultrasound before treatment, 3 mo after treatment and at the end of treatment. Longitudinal and transverse diameters, as well as thickness of hemangiomas measured by clinical observation differed significantly (p < 0.05) from measurements obtained by ultrasound. Ultrasound also revealed that longitudinal and transverse diameters, thickness, vascular density, blood flow velocity (arterial and venous) and arterial peak systolic blood flow velocity of hemangiomas were significantly decreased (p < 0.05) after treatment compared with before treatment. The resistive index and systolic/diastolic blood flow velocity in IHs were significantly higher (p < 0.05) after treatment than before treatment. In conclusion, ultrasound can evaluate the efficacy of propranolol at the termination of therapy.

Correlation between the morning hypertension on ambulatory blood pressure monitoring and the left ventricular mass in children

PURPOSE

Although high morning blood pressure (BP) is known to be associated with the onset of cardiovascular events in adults, data on its effects in children with hypertension are limited. Our retrospective study aimed to define the clinical characteristics of children with morning hypertension (MH) and to determine its associated factors.

METHODS

We reviewed 31 consecutive patients with hypertension, confirmed by the ambulatory blood pressure monitoring (ABPM). We divided these patients into 2 groups: the MH group (n=21, 67.7%), morning BP above the 95th percentile for age and height (2 hours on average after waking up) and the normal morning BP group (n=10, 32.3%). We compared the clinical manifestations, laboratory results, and echocardiographic findings including left ventricular hypertrophy (LVH) between the groups.

RESULTS

The early/atrial (E/A) mitral flow velocity ratio in the MH group was significantly lower than that in the normal morning BP group. In addition, LV mass was higher in the MH group than in the normal morning BP group, although the difference was not statistically significant. The age at the time of hypertension diagnosis was significantly higher in the MH group than in the normal morning BP group (P=0.003). The incidence of hyperuricemia was significantly higher in the MH group than in the normal morning BP group.

CONCLUSION

Older patients and those with hyperuricemia are at higher risk for MH. The rise in BP in the morning is an important factor influencing the development of abnormal relaxation, as assessed by echocardiography. Clinical trials with longer follow-up periods and larger sample sizes are needed to clarify the clinical significance of MH.

Therapeutic options for the treatment of hypertension in children and adolescents

Primary hypertension in children is increasing in prevalence with many cases likely going undiagnosed. The prevalence is currently estimated at between 3%-5% in the United States and may be higher in certain ethnic groups. Primary hypertension, once felt to be rare in children, is now considered to be about five times more common than secondary hypertension. This review provides information to guide physicians through an organized approach to: 1) screening children and adolescents for hypertension during routine visits; 2) using normative percentile data for diagnosis and classification; 3) performing a clinical evaluation to identify the presence of co-morbidities; 4) initiating a plan of care including subsequent follow-up blood pressure measurements, therapeutic lifestyle changes and pharmacologic therapies.

Efficacy and safety of propranolol as first-line treatment for infantile hemangiomas

Beta-blockers are a highly promising treatment modality for complicated infantile hemangiomas (IH). However, data on propranolol as first-line treatment, objective outcome measures and impact on hemodynamics in young infants is limited. We retrospectively evaluated a homogenous group of infants with proliferating complicated IH treated with propranolol (2 mg/kg/day). Outcome was assessed by blinded evaluation of clinical photographs by visual analogue scale (VAS), ultrasound examination and ophthalmological review (if appropriate). Tolerance and hemodynamic variables were recorded over time, including a 2-day in-patient observation at the initiation of therapy. Twenty-five infants (median age 3.6 (1.5-9.1) months) were included in the study. The median follow-up-time was 14 (9-20) months and 14 patients completed treatment at a median age of 14.3 (11.4-22.1) months, after a duration of 10.5 (7.5-16) months. In all patients, there was significant fading of colour (with a VAS of -9 (-6 to -9) after 7 months) and significant decrease in size of the IH (with a VAS of -8 (-3 to -10) after 7 months). Median thickness of the lesions assessed by ultrasound at baseline and after 1 month was 14 (7-28) mm and 10 (5-23) mm, respectively (p < 0.01). In children with periocular involvement, astigmatism and amblyopia resolved rapidly within 8 weeks. The overall tolerance of propranolol was good, and no relevant hemodynamic changes were noted.

CONCLUSION

Our report supports the excellent effect and good tolerance of this novel therapy, and we propose the use of propranolol as first-line treatment for IH.

Propranolol for infantile haemangiomas: insights into the molecular mechanisms of action

Infantile haemangiomas (IH) are the most common benign tumours of infancy. Although most IH are innocuous and 85-90% regress spontaneously, some may become life- or function-threatening and require immediate treatment. Previous standard therapeutic options include physical measures (laser surgery, cryosurgery) and systemic corticosteroids, in severe cases also vincristine, alpha-interferon or cyclophosphamide, all bearing the risk of serious side-effects. Oral propranolol is a very recent therapeutic option for complicated IH with impressive efficacy and generally good tolerance. The effects of propranolol on IH were discovered by chance, and very little is known about its mechanisms of action in IH. Here we present a summary of current knowledge of how propranolol interferes with endothelial cells, vascular tone, angiogenesis and apoptosis. Early, intermediate and long-term effects of propranolol on IH can be attributed to three different pharmacological targets. Early effects (brightening of the haemangioma surface within 1-3 days after start of therapy) are attributable to vasoconstriction due to decreased release of nitric oxide. Intermediate effects are due to the blocking of proangiogenic signals (vascular endothelial growth factor, basic fibroblast growth factor, matrix metalloproteinase 2/9) and result in growth arrest. Long-term effects of propranolol are characterized by induction of apoptosis in proliferating endothelial cells, and result in tumour regression.

Hypertension in adolescents

In adults, hypertension has long been perceived as a public health problem. By contrast, its impact in childhood is far less appreciated. In fact, quite often, high blood pressure in children is not even diagnosed. Blood pressure is a vital sign that is routinely obtained during a physical examination of adults, but only very seldom in children. The diagnosis of hypertension in children is complicated because 'normal' blood pressure values vary with age, sex and height. As a consequence, almost 75% of the cases of arterial hypertension and 90% of the cases of prehypertension in children and adolescents are currently undiagnosed. Furthermore, adolescence hypertension is increasing in prevalence as the prevalence of pediatric obesity has increased. Ambulatory blood pressure monitoring is a useful method for risk evaluation in adolescents. In addition to being viewed as an important cardiovascular risk factor in adolescents, elevated blood pressure should prompt a thorough search for other modifiable risk factors that, if treated, might reduce teenagers' risk of developing cardiovascular disease in adulthood. Thus, assessing blood pressure values in children represents one of the most important measurable markers of cardiovascular risk later in life and a major step in preventive medicine.

Glomerulonephritis and managing the risks of chronic renal disease

The rising global burden of chronic renal disease, the high cost of providing renal replacement therapies, and renal disease also being a risk factor for cardiovascular disease is increasing focus on renal disease prevention. This article focuses on the aspects of renal disease (specifically poststreptococcal glomerulonephritis [PSGN] and chronic kidney disease [CKD]) in Indigenous populations in Australia, New Zealand, Canada, and the United States that diverge from those typically seen in the general population of those countries. The spectrum of renal and many other diseases seen in Indigenous people in developed countries is similar to that seen in developing countries. Diseases like PSGN that have largely disappeared in developed countries still occur frequently in Indigenous people. CKD during the childhood years is due to congenital anomalies of the kidney and urinary tract in up to 70% of cases and occurs later in polycystic kidney disease and childhood-onset diabetes. Several risk factors for CKD in adulthood are already present in childhood.