Dyslipidemia, carotid intima-media thickness and endothelial dysfunction in children with chronic kidney disease

Subclinical target organ damage in a sample of children and adolescents with solitary functioning kidney. A pilot study

BACKGROUND

Patients with solitary functioning kidney appear to be exposed to an increased cardiovascular risk. This study aimed to evaluate the impact of peripheral and central blood pressure on subclinical cardiovascular organ damage in a sample of children and adolescents with solitary functioning kidney.

METHODS

Carotid ultrasonography was performed to measure the carotid intima-media thickness (cIMT) and the carotid distensibility coefficient. The carotid-femoral pulse wave velocity (PWV) was assessed by tonometry. Cardiac mass and remodeling were estimated using transthoracic echocardiography. Central and peripheral (both office and 24-h ambulatory) BP measurements were collected.

RESULTS

Forty-four patients were included. Eighteen subjects (45%) were hypertensive as assessed by 24-h ABPM, with a prevalence of masked hypertension of 43%. Twenty-three subjects (52%) had an increased cIMT, while 2 and 3 patients (5% and 7%) demonstrated an impaired carotid distensibility coefficient and PWV, respectively. Nineteen subjects (43%) showed concentric cardiac remodeling. Central systolic blood pressure (cSBP) correlated with cIMT (r = 0.35) and left ventricular mass index (LVMi) (r = 0.32) demonstrating a positive independent association with an increased cIMT (odds ratio 1.14, 95% confidence interval 1.01-1.29) in multivariate regression analysis.

CONCLUSION

Children and adolescents with solitary functioning kidney exhibited a high prevalence of masked hypertension and subclinical cardiovascular organ damage. These findings support the use of 24-h ABPM to identify patients with a higher cardiovascular risk who would benefit from hypertension treatment and closer monitoring during growth and into adulthood. Additionally, cSBP measurement should be considered as part of a more detailed cardiovascular risk assessment in these patients.

Dyslipidemia in children with chronic kidney disease-findings from the Cardiovascular Comorbidity in Children with Chronic Kidney Disease (4C) study

BACKGROUND

Dyslipidemia is an important and modifiable risk factor for CVD in children with CKD.

METHODS

In a cross-sectional study of baseline serum lipid levels in a large prospective cohort study of children with stage 3-5 (predialysis) CKD, frequencies of abnormal lipid levels and types of dyslipidemia were analyzed in the entire cohort and in subpopulations defined by fasting status or by the presence of nephrotic range proteinuria. Associated clinical and laboratory characteristics were determined by multivariable linear regression analysis.

RESULTS

A total of 681 patients aged 12.2 ± 3.3 years with a mean eGFR of 26.9 ± 11.6 ml/min/1.73 m2 were included. Kidney diagnosis was classified as CAKUT in 69%, glomerulopathy in 8.4%, and other disorders in 22.6% of patients. Nephrotic range proteinuria (defined by a urinary albumin/creatinine ratio > 1.1 g/g) was present in 26.9%. Dyslipidemia was found in 71.8%, and high triglyceride (TG) levels were the most common abnormality (54.7%). Fasting status (38.9%) had no effect on dyslipidemia status. Except for a significant increase in TG in more advanced CKD, lipid levels and frequencies of dyslipidemia were not significantly different between CKD stages. Hypertriglyceridemia was associated with younger age, lower eGFR, shorter duration of CKD, higher body mass index (BMI-SDS), lower serum albumin, and higher diastolic blood pressure.

CONCLUSIONS

Dyslipidemia involving all lipid fractions, but mainly TG, is present in the majority of patients with CKD irrespective of CKD stage or fasting status and is significantly associated with other cardiovascular risk factors.

Serum apolipoproteins (apoA-1, apoB, and apoB/apoA-1 ratio) for early identification of dyslipidemia in children with CKD

BACKGROUND

Dyslipidemia in children with chronic kidney disease (CKD) is identified based on lipid profile parameters; however, changes in lipoprotein quality precede quantitative changes.

METHODS

A cross-sectional study was done from January to October 2021; overweight, obese children, known cases of diabetes mellitus, hypothyroidism or on steroid therapy, or lipid lowering drugs were excluded. Clinical details were elicited and examinations done. Besides hemogram, kidney function tests, liver function tests, total cholesterol, low density lipoproteins (LDL), triglycerides, high density lipoproteins (HDL), and apolipoproteins A-1 and B were estimated to identify dyslipidemia. Relevant tests of significance were applied, and ROC curves were drawn for apoA-1, apoB, and apoB/apoA-1 ratios.

RESULTS

A total of 76 (61 M:15 F) children with median (IQR) age 7 (3.25-11) years were enrolled; cause of CKD was CAKUT in 82.3% patients. Dyslipidemia (alteration of 1 or more lipid parameters) was seen in 78.9% with a prevalence of 71.7% in early and 95.7% in later stages of CKD (P = 0.02); most had elevated serum triglyceride levels. The median (IQR) values of apoB, apoA-1, and apoB/apoA-1 ratio were 78 (58-110) mg/dl, 80 (63-96.75) mg/dl, and 0.88 (0.68-1.41), respectively; apoB, apoA-1, and apoB/apoA-1 ratio had a sensitivity of 26.67%, 86.67%, and 70%, respectively, and specificity of 87.5%, 62.5%, and 62.5%, respectively, for diagnosis of dyslipidemia. The ROC for apoB, apoA-1, and apoB/apoA-1 ratio showed AUC of 0.66, 0.68, and 0.74 (P = 0.4, 0.02, < 0.01), respectively.

CONCLUSIONS

The prevalence (78.9%) of dyslipidemia was high in patients with CKD especially in those with later stages. The ratio of apoB/apoA-1 was altered early and appears to be promising for early detection.

Endothelial dysfunction as a factor leading to arterial hypertension

Hypertension remains the main cause of cardiovascular complications leading to increased mortality. The discoveries of recent years underline the important role of endothelial dysfunction (ED) in initiating the development of arterial hypertension. The endothelium lines the interior of the entire vascular system in the body and acts as a physical barrier between blood and tissues. Substances and mediators produced by the endothelium exhibit antithrombotic and anti-inflammatory properties. Oxidative stress and inflammation are conditions that damage the endothelium and shift endothelial function from vasoprotective to vasoconstrictive, prothrombotic, and pro-apoptotic functions. A dysfunctional endothelium contributes to the development of hypertension and further cardiovascular complications. Reduced nitric oxide (NO) bioavailability plays an essential role in the pathophysiology of ED-associated hypertension. New technologies provide tools to identify pathological changes in the structure and function of the endothelium. Endothelial dysfunction (ED) contributes to the development of arterial hypertension and should be considered in therapeutic strategies for children with hypertension.

Short-term safety and efficacy of escalating doses of atorvastatin for dyslipidemia in children with predialysis chronic kidney disease stage 2-5

BACKGROUND

Dyslipidemia is a potentially modifiable risk factor in patients with chronic kidney disease (CKD). Information on the safety and efficacy of statins in pediatric CKD is limited.

METHODS

Patients with CKD stage 2-5 and aged 5-18 years with low-density lipoprotein cholesterol (LDL-C) > 130 mg/dL and/or non-high-density lipoprotein cholesterol (non-HDL-C) > 145 mg/dL were enrolled from September 2019 to February 2021. All patients were administered atorvastatin 10 mg/day, which was escalated to 20 mg/day if LDL-C remained > 100 mg/dL and/or non-HDL-C > 120 mg/dL at 12 weeks. Proportion of patients achieving target lipid levels (LDL-C ≤ 100 mg/dL and non-HDL-C ≤ 120 mg/dL) and adverse events were assessed at 24 weeks.

RESULTS

Of 31 patients enrolled, target lipid levels were achieved in 45.2% (95% CI 27.8-63.7%) at 24 weeks; 22 patients required dose escalation to 20 mg at 12 weeks. There was no difference in median lipid level reduction with 10 (n = 9) versus 20 mg/day (n = 22, P = 0.3). Higher baseline LDL-C (OR 1.06, 95% CI 1.00-1.11) and older age (OR 36.5, 95% CI 2.57-519.14) were independent predictors of failure to achieve target lipid levels with 10 mg/day atorvastatin. None had persistent rise in AST/ALT > 3 times upper normal limit (UNL) or CPK > 10 times UNL. No differences were noted in adverse events due to atorvastatin 10 or 20 mg/day.

CONCLUSION

Atorvastatin (10-20 mg/day) administered for 24 weeks was safe and effectively reduced LDL-C and non-HDL-C in children with CKD stages 2-5. Patients with higher baseline LDL-C required higher doses to achieve the target. A higher resolution version of the Graphical abstract is available as Supplementary information.

Cardiovascular Risks of Hypertension: Lessons from Children with Chronic Kidney Disease

Hypertension is the most common complication of chronic kidney disease (CKD) in children, having a strong association with subsequential cardiovascular disease (CVD). In pediatric CKD, a considerable percentage of children with hypertension are undiagnosed or undertreated. Prior research has evaluated structural and functional markers of subclinical CVD and biomarkers in adults with CKD, while ideal biomarkers in pediatrics are still insufficiently studied. The ultimate goal of this review is to summarize what is currently known about state of hypertension, cardiovascular risk factors, and potential CVD markers/biomarkers in children with pre-dialysis CKD. We discuss omics-related biomarkers and the pathophysiologic processes of endothelial dysfunction, kidney injury, oxidative stress and inflammation that are classified by specific biomarkers. Moreover, we illustrate the existing challenges and highlight the paucity of pediatric CKD research to evaluate these CVD biomarkers for future clinical pediatric practice. Thus, achieving clinical utility of CVD biomarkers for use in pediatric CKD remains a significant challenge requiring additional efforts.

Current applications for measuring pediatric intima-media thickness

Intima-media thickness is a known subclinical radiologic marker of the early manifestations of atherosclerotic disease. It is the thickness of the vessel wall, most often the carotid artery. Intima-media thickness is measured on conventional US manually or automatically. Other measurement techniques include radiofrequency US. Because there is variation in its measurement, especially in children, several recommendations have been set to increase the measurement's validity and comparability among studies. Despite these recommendations, several pitfalls should be avoided, and quality control should be performed to avoid erroneous interpretation. This article summarizes current literature in relation to the clinical applications for intima-media thickness measurement in children with known risk factors such as obesity, liver steatosis, hypercholesterolemia, diabetes, hypertension, systemic inflammatory diseases, cancer survival, kidney and liver transplant, and sickle cell disease or beta thalassemia major. Most potential indications for intima-media thickness measurement remain in the research domain and should be interpreted combined with other markers. The objective of diagnosing an increased intima-media thickness is to start a multidisciplinary treatment approach to prevent disease progression and its sequelae in adulthood.

Pediatric Mineral and Bone Disorder of Chronic Kidney Disease and Cardiovascular Disease

Chronic kidney disease is common and causes significant morbidity including shortened lifespans and decrease in quality of life for patients. The major cause of mortality in chronic kidney disease is cardiovascular disease. Cardiovascular disease within the chronic kidney disease population is closely tied with disordered calcium and phosphorus metabolism and driven in part by renal bone disease. The complex nature of renal, bone, and cardiovascular diseases was renamed as mineral and bone disorder of chronic kidney disease to encompass how bone disease drives vascular calcification and contributes to the development of long-term cardiovascular disease, and recent data suggest that managing bone disease well can augment and improve cardiovascular disease status. Pediatric nephrologists have additional obstacles in optimal mineral and bone disorder of chronic kidney disease management such as linear growth and skeletal maturation. In this article, we will discuss cardiovascular and bone diseases in chronic kidney disease and end-stage kidney disease patients with a focus on pediatric issues and concerns.

Pulse Wave Velocity, Central Haemodynamic Parameters, and Markers of Kidney Function in Children

OBJECTIVES

Chronic kidney disease (CKD) is a well-established risk factor for cardiovascular diseases. Studies in adults have demonstrated the association between mildly decreased kidney function or even normal values of markers of kidney function to pulse wave velocity (PWV), a measure of arterial stiffness and a predictor of cardiovascular events. Our study aimed to evaluate associations between markers of CKD, PWV, and central haemodynamic parameters in children and adolescents at risk of subclinical kidney damage.

METHODS

182 children and adolescents with hypertension, obesity, or hypercholesterolaemia (risk factors for subclinical kidney damage) were included in the study. The subjects were subdivided into 4 groups comprising children and adolescents with hypertension (group 1), obesity (group 2), hypercholesterolaemia (group 3), and a group with a combination of risk factors, such as obesity-related hypertension and metabolic syndrome (group 4). The study groups were compared to a group of healthy controls (group 5). PWV was measured by applanation tonometry (SphygmoCor, SCOR-Vx, Sydney, NSW, Australia) and laboratory parameters (serum creatinine, serum cystatin C, and microalbuminuria) were collected.

RESULTS

Pearson's correlation coefficient demonstrated a statistically significant correlation between PWV and serum creatinine in group of all subjects (r = 0.220, p = 0.002). Further subdivision showed the correlation was significant in group 4 (r = 0.370, p = 0.002). In group 2 a correlation between PWV and cystatin C was found (r = -0.535, p = 0.009). In multiple regression analysis of all subjects with PWV as the dependent variable, age and diastolic blood pressure were statistically significant. Correlations between markers of kidney function and central haemodynamic parameters also showed significant correlations between serum creatinine and heart rate (HR) (r = -0.476, p < 0.001) as well as associated parameters (augmentation index, standardized at HR 75/min, ejection duration, and subendocardial viability ratio).

CONCLUSIONS

Our study demonstrated a correlation between serum creatinine and PWV in children with combined risk factors for atherosclerosis and probable subclinical kidney damage. Further prospective research is needed to confirm the findings, and thus the preventive role of PWV determination in paediatric nephrology.

Narrative Review of Carotid disease and the kidney

Patients with chronic kidney disease (CKD) have an increased cardiovascular (CV) risk that is only in part explained by established risk factors. Carotid arteriosclerosis and atherosclerosis are increased in CKD, play a role in the causation of CV disease in these patients and can affect the progression of renal disease. The arterial stiffening process is evident even in CKD patients with a very mild reduction of glomerular filtration rate (GFR) whereas arterial thickening is evident in more advanced stages. Possible mechanisms include functional and structural alterations of the arterial wall. Arterial stiffness can mediate the effect of CKD on target organs (i.e., brain, kidney and heart). In this review we discuss the arterial phenotype of patients with CKD. This is characterized by increased common carotid artery stiffness and outward remodeling (enlargement and thickening of the arterial wall) and a normal/reduced stiffness paired with an inward remodeling (narrowing of the arterial wall) of muscular arteries. We also discuss the consequences of carotid dysfunction, including the involvement of large elastic arteries stiffness on ventricular-vascular coupling, the mechanisms linking carotid stiffening and increased cardio- and cerebrovascular risk in CKD patients, and the therapeutic options to improve carotid function.

Endothelial dysfunction in children with chronic kidney disease

BACKGROUND AND OBJECTIVE

Cardiovascular disease (CVD) is the main cause of death in children with chronic kidney disease (CKD). Inflammation and endothelial dysfunction (ED) are found in the majority of these patients and are factors associated to CVD. Flow mediated dilatation (FMD) is a surrogate marker validated for evaluating ED. Our objective was to identify risk factors associated to ED in children with CKD.

MATERIALS AND METHODS

Children 2-16 years of age were studied. Clinical information and biochemical variables were gathered, including intact parathyroid hormone (iPTH), interleukins 6 and 1b, high sensitivity C reactive protein (hsCRP), reduced glutathione, nitric oxide, malondialdehyde and homocysteine. FMD was measured, and considered altered if <7%.

RESULTS

Included were 129 patients aged 13.1 ± 2.6 years. FMD < 7% was found in 69 (52.7%). Patients with altered FMD had higher levels of triglycerides and hsCRP than those with normal FMD (145.5 mg/dl vs. 120.0 mg/dl, P = .042, y 1.24 U/L vs. 0.55 U/L, P = .007, respectively), as well as higher frequency of low iPTH (19.1% vs. 4.9%, P = .036). Levels of hsCRP correlated significantly with FMD (Rho = -0.28, P = .003). Patients with low iPTH (OR = 4.41, 95%CI 1.13-17.27, P = .033) and increased hsCRP (OR = 2.89, 95%CI 1.16-7.17, P = .022) had higher adjusted risk of having FMD < 7%.

CONCLUSIONS

Hypertriglyceridemia, inflammation and low iPTH associated significantly with altered FMD. They are frequent, treatable risk factors for CVD.

Endothelial dysfunction in children with chronic kidney disease

BACKGROUND AND OBJECTIVE

Cardiovascular disease is the main cause of death in children with chronic kidney disease. Inflammation and endothelial dysfunction are found in the majority of these patients and are factors associated to cardiovascular disease. Flow mediated dilatation (FMD) is a surrogate marker validated for evaluating endothelial dysfunction. Our objective was to identify risk factors associated to endothelial dysfunction in children with chronic kidney disease.

MATERIALS AND METHODS

Children 2-16 years of age were studied. Clinical information and biochemical variables were gathered, including intact parathyroid hormone (iPTH), interleukins 6 and 1β, high sensitivity C reactive protein (hsCRP), reduced glutathione, nitric oxide, malondialdehyde and homocysteine. FMD was measured, and considered altered if<7%.

RESULTS

Included were 129 patients aged 13.1±2.6 years. FMD<7% was found in 69 (52.7%). Patients with altered FMD had higher levels of triglycerides and hsCRP than those with normal FMD (145.5 vs. 120.0mg/dL, P=.042, and 1.24 vs. 0.55U/L, P=.007, respectively), as well as higher frequency of low iPTH (19.1 vs. 4.9%, P=.036). Levels of hsCRP correlated significantly with FMD (Rho=-0.28, P=.003). Patients with low iPTH (OR 4.41, 95% CI 1.13-17.27, P=.033) and increased hsCRP (OR 2.89, 95% CI 1.16-7.17, P=.022) had higher adjusted risk of having FMD<7%.

CONCLUSIONS

Hypertriglyceridemia, inflammation and low iPTH associated significantly with altered FMD. They are frequent, treatable risk factors for cardiovascular disease.

Fibroblast Growth Factor 23 and Left Ventricular Hypertrophy in Chronic Kidney Disease-A Pediatric Perspective

Cardiovascular diseases (CVD) are a hallmark in pediatric patients with chronic kidney disease (CKD) contributing to an enhanced risk of all-cause and CV morbidity and mortality in these patients. The bone-derived phosphaturic hormone fibroblast growth factor (FGF) 23 progressively rises with declining kidney function to maintain phosphate homeostasis, with up to 1,000-fold increase in patients with kidney failure requiring dialysis. FGF23 is associated with the development of left ventricular hypertrophy (LVH) and thereby accounts to be a CVD risk factor in CKD. Experimentally, FGF23 directly induces hypertrophic growth of cardiac myocytes in vitro and LVH in vivo. Further, clinical studies in adult CKD have observed cardiotoxicity associated with FGF23. Data regarding prevalence and determinants of FGF23 excess in children with CKD are limited. This review summarizes current data and discusses whether FGF23 may be a key driver of LVH in pediatric CKD.

Nocturnal hypertension and left ventricular hypertrophy in pediatric renal transplant recipients in South India

HTN after renal transplantation is associated with cardiovascular morbidity. ABPM allows diagnosis of masked HTN and isolated nocturnal HTN. Longitudinal ABPM data in children post-transplant are limited. ABPM was performed in children post-transplant and repeated in 6-12 months. BP indices were used to determine the prevalence of masked HTN, masked uncontrolled HTN (masked HTN in patients on antihypertensive medications), and isolated nocturnal HTN. Linear regression determined the association between LVMI and ABPM indices. Thirty children underwent a baseline ABPM. Ambulatory HTN was present in 25 (83%). Masked HTN was present in 18 (60%) and isolated nocturnal HTN in 13 (43%). Nocturnal ambulatory BP was higher than corresponding daytime BPs (P < .001 for systolic and diastolic) and 25 (83%) had a blunted nocturnal dip. Prednisone dose predicted nocturnal DBP index and DBP load (r²  = .40, P = .024 and r²  = .178, P = .02). ABPM was repeated in 18 patients within 11 (±3) months. BP indices decreased with time, but nocturnal BPs remained higher than daytime (P < .001 for SBP and DBP). Blunted nocturnal dip did not improve. LVH was present in 12 (57%). LVMI was directly related to the nocturnal SBP index (r²  = .377, P = .003) and nocturnal DBP index (r²  = .493, P < .001). We found no association between LVMI and daytime BP indices. The prevalence of masked HTN, isolated nocturnal HTN, and blunted nocturnal dip was high in children with kidney transplants. Nocturnal BP predicted LVMI. Ambulatory BP improved on longitudinal follow-up, but the pattern of isolated nocturnal HTN persisted.

Cardiovascular risk factors in children on dialysis: an update

Cardiovascular disease (CVD) is a life-limiting comorbidity in patients with chronic kidney disease (CKD). In childhood, imaging studies have demonstrated early phenotypic characteristics including increases in left ventricular mass, carotid artery intima-media thickness, and pulse wave velocity, which occur even in young children with early stages of CKD. Vascular calcifications are the signature of an advanced phenotype and are mainly found in adolescents and young adults treated with dialysis. Association studies have provided valuable information regarding the significance of a multitude of risk factors in promoting CVD in children with CKD by using intermediate endpoints of measurements of surrogate parameters of CVD. Dialysis aggravates pre-existing risk factors and accelerates the progression of CVD with additional dialysis-related risk factors. Coronary artery calcifications in children and young adults with CKD accumulate in a time-dependent manner on dialysis. Identification of risk factors has led to improved understanding of principal mechanisms of CKD-induced damage to the cardiovascular system. Treatment strategies include assessment and monitoring of individual risk factor load, optimization of treatment of modifiable risk factors, and intensified hemodialysis if early transplantation is not possible.

Endothelium structure and function in kidney health and disease

The kidney harbours different types of endothelia, each with specific structural and functional characteristics. The glomerular endothelium, which is highly fenestrated and covered by a rich glycocalyx, participates in the sieving properties of the glomerular filtration barrier and in the maintenance of podocyte structure. The microvascular endothelium in peritubular capillaries, which is also fenestrated, transports reabsorbed components and participates in epithelial cell function. The endothelium of large and small vessels supports the renal vasculature. These renal endothelia are protected by regulators of thrombosis, inflammation and complement, but endothelial injury (for example, induced by toxins, antibodies, immune cells or inflammatory cytokines) or defects in factors that provide endothelial protection (for example, regulators of complement or angiogenesis) can lead to acute or chronic renal injury. Moreover, renal endothelial cells can transition towards a mesenchymal phenotype, favouring renal fibrosis and the development of chronic kidney disease. Thus, the renal endothelium is both a target and a driver of kidney and systemic cardiovascular complications. Emerging therapeutic strategies that target the renal endothelium may lead to improved outcomes for both rare and common renal diseases.

Evaluation of carotid intima-media thickness and factors associated with cardiovascular disease in children and adolescents with chronic kidney disease

OBJECTIVE

To assess the carotid intima-media thickness and factors associated with cardiovascular disease in children and adolescents with chronic kidney disease.

MATERIAL AND METHODS

Observational, cross-sectional study carried out at the Universidade Federal de São Paulo (chronic kidney disease outpatient clinics) with 55 patients (60% males) with a median age of 11.9 years (I25-I75: 9.2-14.8 years). Of the 55 patients, 43 were on conservative treatment and 12 were on dialysis. Serum laboratory parameters (creatinine, uric acid, C-reactive protein, total cholesterol and fractions, and triglycerides), nutritional status (z-score of body mass index, z-score of height/age), body fat (fat percentage and waist circumference), and blood pressure levels were evaluated. The carotid intima-media thickness measure was evaluated by a single ultrasonographer and compared with percentiles established according to gender and height. Data collection was performed between May 2015 and March 2016.

RESULTS

Of the children and adolescents with chronic kidney disease, 74.5% (95% CI: 61.0; 85.3) showed an increase (>P95) in carotid intima-media thickness. In patients with stages I and II hypertension, 90.9% had increased carotid intima-media thickness. Nutritional status, body fat and laboratory tests were not associated with increased carotid intima-media thickness. After multivariate adjustment, only puberty (PR=1.30, p=0.037) and stages I and II arterial hypertension (PR=1.42, p=0.011) were independently associated with carotid intima-media thickness alterations.

CONCLUSION

The prevalence of increased carotid thickness was high in children and adolescents with chronic kidney disease. Puberty and arterial hypertension were independently associated with increased carotid intima-media thickness.

Impact of dyslipidemia on estimated glomerular filtration rate in apparently healthy children and adolescents: the CASPIAN-V study

BACKGROUND

Chronic kidney disease (CKD) is a leading risk factor for development of cardiovascular disease (CVD). Dyslipidemia is also known as risk factor for CVD development. However, the association of dyslipidemia with glomerular injury among healthy children and adolescents remains controversial. We aimed to investigate the relationship between estimated glomerular filtration rate (eGFR) and lipid profile risk factors among healthy children and adolescents.

METHODS

In this nationwide survey, 3808 participants (1992 males, 1816 females), aged 7-18 years, were selected by cluster random sampling method from 30 provinces in Iran. Body mass index (BMI) and systolic and diastolic blood pressures were measured. Blood samples were obtained for serum creatinine, fasting blood glucose, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) determinations. GFR was estimated using Schwartz equation.

RESULTS

Girls had higher eGFR than boys (P = 0.04). In a multiple regression analysis, eGFR demonstrated a positive correlation with systolic blood pressure, BMI, fasting glucose, TC, HDL-C, and TG. By the analysis of covariance, TC, HDL-C, and TG showed a negative correlation with eGFR after adjustments for BMI, systolic and diastolic blood pressures, and fasting glucose (OR = 0.56, 95% CI = 0.29-0.89).

CONCLUSION

The study showed that dyslipidemia is associated with reduced eGFR among the healthy children and adolescents.

Atherosclerosis in Chronic Kidney Disease: More, Less, or Just Different?

Patients with chronic kidney disease (CKD) are at an increased risk of premature mortality, mainly from cardiovascular causes. The association between CKD on hemodialysis and accelerated atherosclerosis was described >40 years ago. However, more recently, it has been suggested that the increase in atherosclerosis risk is actually observed in early CKD stages, remaining stable thereafter. In this regard, interventions targeting the pathogenesis of atherosclerosis, such as statins, successful in the general population, have failed to benefit patients with very advanced CKD. This raises the issue of the relative contribution of atherosclerosis versus other forms of cardiovascular injury such as arteriosclerosis or myocardial injury to the increased cardiovascular risk in CKD. In this review, the pathophysiogical contributors to atherosclerosis in CKD that are shared with the general population, or specific to CKD, are discussed. The NEFRONA study (Observatorio Nacional de Atherosclerosis en NEFrologia) prospectively assessed the prevalence and progression of subclinical atherosclerosis (plaque in vascular ultrasound), confirming an increased prevalence of atherosclerosis in patients with moderate CKD. However, the adjusted odds ratio for subclinical atherosclerosis increased with CKD stage, suggesting a contribution of CKD itself to subclinical atherosclerosis. Progression of atherosclerosis was closely related to CKD progression as well as to the baseline presence of atheroma plaque, and to higher phosphate, uric acid, and ferritin and lower 25(OH) vitamin D levels. These insights may help design future clinical trials of stratified personalized medicine targeting atherosclerosis in patients with CKD. Future primary prevention trials should enroll patients with evidence of subclinical atherosclerosis and should provide a comprehensive control of all known risk factors in addition to testing any additional intervention or placebo.

Oxidative stress in chronic kidney disease

Oxidative stress (OS), defined as disturbances in the pro-/antioxidant balance, is harmful to cells due to the excessive generation of highly reactive oxygen (ROS) and nitrogen (RNS) species. When the balance is not disturbed, OS has a role in physiological adaptations and signal transduction. However, an excessive amount of ROS and RNS results in the oxidation of biological molecules such as lipids, proteins, and DNA. Oxidative stress has been reported in kidney disease, due to both antioxidant depletions as well as increased ROS production. The kidney is a highly metabolic organ, rich in oxidation reactions in mitochondria, which makes it vulnerable to damage caused by OS, and several studies have shown that OS can accelerate kidney disease progression. Also, in patients at advanced stages of chronic kidney disease (CKD), increased OS is associated with complications such as hypertension, atherosclerosis, inflammation, and anemia. In this review, we aim to describe OS and its influence on CKD progression and its complications. We also discuss the potential role of various antioxidants and pharmacological agents, which may represent potential therapeutic targets to reduce OS in both pediatric and adult CKD patients.

Cardiovascular Disease in Children and Adolescents With Chronic Kidney Disease

The lifespan of children with advanced chronic kidney disease (CKD), although improved over the past 2 decades, remains low compared with the general pediatric population. Similar to adults with CKD, cardiovascular disease accounts for a majority of deaths in children with CKD because these patients have a high prevalence of traditional and uremia-related risk factors for cardiovascular disease. The cardiovascular alterations that cause these terminal events begin early in pediatric CKD. Initially, these act to maintain hemodynamic homeostasis. However, as the disease progresses, these modifications are unable to sustain cardiovascular function in the long term, leading to left ventricular failure, depressed cardiorespiratory fitness, and sudden death. In this review, we discuss the prevalence of the risk factors associated with cardiovascular disease in pediatric patients with CKD, the pathophysiology that stimulates these changes, the cardiac and vascular adaptations that occur in these patients, and management of the cardiovascular risk in these patients.

Assessment of subclinical atherosclerosis and endothelial dysfunction in chronic kidney disease by measurement of carotid intima media thickness and flow-mediated vasodilatation in North Indian population

Background:

Chronic kidney disease (CKD) predisposes to accelerated atherosclerosis that is measured by carotid artery intima media thickness (CIMT) and brachial artery flow-mediated dilation (FMD). The aim of this study was to assess the noninvasive risk markers of subclinical atherosclerosis and endothelial dysfunction and their correlation with disease severity.

Methods and Results:

This was a cross-sectional study conducted in 62 patients with CKD: 38 predialysis and 24 on hemodialysis and 50 age- and gender-matched controls. In both the patients and controls, high-sensitivity C-reactive protein (CRP) levels, %FMD, and CIMT were measured. Patients with CKD had increased CRP levels {[5.8 (1.0–6.0)] mg/L vs [1.0 (0.5–2.20)] mg/L; P < 0.001}; %FMD was significantly lower in patients on hemodialysis (5.51%) compared with stage IV (7.62%) and stage III (15.02%) and 17.95% in control subjects (P < 0.001); and CIMT values in hemodialysis patients (0.88 ± 0.06 mm) were significantly higher compared with stage IV (0.67 ± 0.10) and stage III (0.61 ± 0.12) (P < 0.001). Increased CIMT values were seen in patients with CKD (0.82 ± 0.21 mm) than in the healthy controls (0.55 ± 0.16 mm). In patients with CKD, a significant negative correlation was found between CRP levels and FMD responses (r = −0.315; P < 0.001), while a significant positive correlation was found between CRP and CIMT values (r = 0.327; P < 0.001). Compared with predialysis, hemodialysis subjects had significantly lower FMD and higher CRP and IMT values.

Conclusion:

CKD confers a higher inflammatory status when compared with apparently healthy general population. Abnormal FMD responses and CIMT values are more commonly found in dialysis patients. Our findings suggest that CIMT and FMD can be used as noninvasive markers for early risk assessment and stratification in various stages of CKD.

Role of hypertension in progression of chronic kidney disease in children

PURPOSE OF REVIEW

Hypertension is an independent risk factor for progression of chronic kidney disease (CKD) in children. Children with early CKD develop hypertension secondary to renal disease. This review aims to highlight recent advances that help us better understand the current role of hypertension in progression of CKD in children.

RECENT FINDINGS

There is increasing evidence that children with CKD who have hypertension develop early atherosclerosis and cardiac adaptive changes. Emerging data from pediatric research in CKD show that elevated blood pressure is associated with the presence of abnormal subclinical markers of cardiovascular disease including increased carotid intima-media thickness, pulse wave velocity and left ventricular mass index. There is also some evidence that these early cardiovascular changes are reversible. Twenty-four hour ambulatory blood pressure monitoring (ABPM) is recommended in children with CKD by the American Academy of Pediatrics to diagnose hypertension.

SUMMARY

Hypertension is associated with subclinical cardiovascular disease in children with CKD. Early diagnosis of hypertension by ABPM and identification of subclinical cardiovascular changes provide a window for intervention, which may reverse early cardiovascular disease, thereby delaying dialysis and improving cardiovascular morbidity and mortality.

Cardiovascular Phenotypes in Children with CKD: The 4C Study

BACKGROUND AND OBJECTIVES

Cardiovascular disease is the most important comorbidity affecting long-term survival in children with CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The Cardiovascular Comorbidity in Children with CKD Study is a multicenter, prospective, observational study in children ages 6-17 years old with initial GFR of 10-60 ml/min per 1.73 m2. The cardiovascular status is monitored annually, and subclinical cardiovascular disease is assessed by noninvasive measurements of surrogate markers, including the left ventricular mass index, carotid intima-media thickness, and central pulse wave velocity. We here report baseline data at study entry and an explorative analysis of variables associated with surrogate markers.

RESULTS

A total of 737 patients were screened from October of 2009 to August of 2011 in 55 centers in 12 European countries, and baseline data were analyzed in 688 patients. Sixty-four percent had congenital anomalies of the kidney and urinary tract; 26.1% of children had uncontrolled hypertension (24-hour ambulatory BP monitoring; n=545), and the prevalence increased from 24.4% in CKD stage 3 to 47.4% in CKD stage 5. The prevalence of left ventricular hypertrophy was higher with each CKD stage, from 10.6% in CKD stage 3a to 48% in CKD stage 5. Carotid intima-media thickness was elevated in 41.6%, with only 10.8% of patients displaying measurements below the 50th percentile. Pulse wave velocity was increased in 20.1%. The office systolic BP SD score was the single independent factor significantly associated with all surrogate markers of cardiovascular disease. The intermediate end point score (derived from the number of surrogate marker measurements >95th percentile) was independently associated with a diagnosis of congenital anomalies of the kidney and urinary tract, time since diagnosis of CKD, body mass index, office systolic BP, serum phosphorus, and the hemoglobin level.

CONCLUSIONS

The baseline data of this large pediatric cohort show that surrogate markers for cardiovascular disease are closely associated with systolic hypertension and stage of CKD.

A thicker intima-media carotid wall was found in a cohort of children with recent onset migraine

AIM

Migraine affects approximately 10-20% of the general population, including children and adolescents, and an association between migraine and increased risks for cardiovascular disease and stroke have been reported in adult patients. This study aimed to address the lack of data on children with migraine.

METHODS

This study comprised 30 children and adolescents (16 male) with migraine. We evaluated their biochemical profile, glucose homeostasis, vascular function by flow-mediated dilatation and arterial structure by carotid intima-media thickness (cIMT). A group of 32 age, sex and auxologically matched children (17 male) served as controls.

RESULTS

The group of children with migraine had a normal biochemical profile and glucose homeostasis, but presented with significantly thicker cIMT than the control group (0.48 ± 0.07 mm versus 0.45 ± 0.04, p < 0.05).

CONCLUSION

We observed a significantly thicker cIMT in children with migraine compared with the controls. The brief time interval between the onset of the disease and the time of the study makes it unlikely that repetitive migraine attacks could be responsible for the thickening of the cIMT. Thus, it may be speculated that primitive vascular function abnormalities were wholly or partly responsible for the development of migraine in this paediatric cohort.