Cholesterol curves to identify population norms by age and sex in healthy weight children

A Proposed Pediatric Clinical Cardiovascular Health Reference Standard

INTRODUCTION

Clinical cardiovascular health is a construct that includes 4 health factors-systolic and diastolic blood pressure, fasting glucose, total cholesterol, and body mass index-which together provide an evidence-based, more holistic view of cardiovascular health risk in adults than each component separately. Currently, no pediatric version of this construct exists. This study sought to develop sex-specific charts of clinical cardiovascular health for age to describe current patterns of clinical cardiovascular health throughout childhood.

METHODS

Data were used from children and adolescents aged 8-19 years in six pooled childhood cohorts (19,261 participants, collected between 1972 and 2010) to create reference standards for fasting glucose and total cholesterol. Using the models for glucose and cholesterol as well as previously published reference standards for body mass index and blood pressure, clinical cardiovascular health charts were developed. All models were estimated using sex-specific random-effects linear regression, and modeling was performed during 2020-2022.

RESULTS

Models were created to generate charts with smoothed means, percentiles, and standard deviations of clinical cardiovascular health for each year of childhood. For example, a 10-year-old girl with a body mass index of 16 kg/m2 (30th percentile), blood pressure of 100/60 mm Hg (46th/50th), glucose of 80 mg/dL (31st), and total cholesterol of 160 mg/dL (46th) (lower implies better) would have a clinical cardiovascular health percentile of 62 (higher implies better).

CONCLUSIONS

Clinical cardiovascular health charts based on pediatric data offer a standardized approach to express clinical cardiovascular health as an age- and sex-standardized percentile for clinicians to assess cardiovascular health in childhood to consider preventive approaches at early ages and proactively optimize lifetime trajectories of cardiovascular health.

Association of Blood Calcidiol Levels and Metabolic Syndrome in Children and Adolescents With Vitamin D Deficiency

This retrospective cohort study aimed to determine whether severe calcidiol deficiency [25-hydroxyvitamin (OH)D <30 nmol/L] improvement has a beneficial effect on cardiometabolic parameters in children and adolescents (5-17 years) with or without metabolic syndrome (MetS). Logistic regression analysis was performed to test for multivariate associations between potential confounders and changes in vitamin D (VD) status from baseline to follow-up care when predicting binary categorical outcomes. Of 562 participants, 146 (26%) had MetS. Individuals with severe VD deficiency (VDD) were more likely to have MetS with elevated blood pressure than those with sufficient (≥75 nmol) VD levels (adjusted odds ratio [AOR], 4.46; 1.08-18.43; p < .05) at follow-up. In the logistic regression model, every unit increase in VD across time decreased the odds of MetS (AOR, 0.98; 95% confidence interval: [0.96, 0.99]; p < .05). Improvement in VD status demonstrated a beneficial metabolic effect in children and adolescents with severe VDD.

Detrimental effects of PCSK9 loss-of-function in the pediatric host response to sepsis are mediated through independent influence on Angiopoietin-1

BACKGROUND

Sepsis is associated with significant mortality. Yet, there are no efficacious therapies beyond antibiotics. PCSK9 loss-of-function (LOF) and inhibition, through enhanced low-density lipoprotein receptor (LDLR) mediated endotoxin clearance, holds promise as a potential therapeutic approach among adults. In contrast, we have previously demonstrated higher mortality in the juvenile host. Given the potential pleiotropic effects of PCSK9 on the endothelium, beyond canonical effects on serum lipoproteins, both of which may influence sepsis outcomes, we sought to test the influence of PCSK9 LOF genotype on endothelial dysfunction.

METHODS

Secondary analyses of a prospective observational cohort of pediatric septic shock. Genetic variants of PCSK9 and LDLR genes, serum PCSK9, and lipoprotein concentrations were determined previously. Endothelial dysfunction markers were measured in day 1 serum. We conducted multivariable linear regression to test the influence of PCSK9 LOF genotype on endothelial markers, adjusted for age, complicated course, and low- and high-density lipoproteins (LDL and HDL). Causal mediation analyses to test impact of select endothelial markers on the association between PCSK9 LOF genotype and mortality. Juvenile Pcsk9 null and wildtype mice were subject to cecal slurry sepsis and endothelial markers were quantified.

RESULTS

A total of 474 patients were included. PCSK9 LOF was associated with several markers of endothelial dysfunction, with strengthening of associations after exclusion of those homozygous for the rs688 LDLR variant that renders it insensitive to PCSK9. Serum PCSK9 was not correlated with endothelial dysfunction. PCSK9 LOF influenced concentrations of Angiopoietin-1 (Angpt-1) upon adjusting for potential confounders including lipoprotein concentrations, with false discovery adjusted p value of 0.042 and 0.013 for models that included LDL and HDL, respectively. Causal mediation analysis demonstrated that the effect of PCSK9 LOF on mortality was mediated by Angpt-1 (p = 0.0008). Murine data corroborated these results with lower Angpt-1 and higher soluble thrombomodulin among knockout mice with sepsis relative to the wildtype.

CONCLUSIONS

We present genetic and biomarker association data that suggest a potential direct role of the PCSK9-LDLR pathway on Angpt-1 in the developing host with septic shock and warrant external validation. Further, mechanistic studies on the role of PCSK9-LDLR pathway on vascular homeostasis may lead to the development of pediatric-specific sepsis therapies.

Does low-density lipoprotein fully explain atherosclerotic risk in familial hypercholesterolemia?

PURPOSE OF REVIEW

Familial hypercholesterolemia (FH) is a monogenic disorder of elevated low-density lipoprotein cholesterol (LDL-C) from birth leading to increased risk for atherosclerotic cardiovascular disease. However, not all carriers of FH variants display an FH phenotype. Despite this fact, FH variants confer increased risk for atherosclerotic disease in population cohorts. An important question to consider is whether measurements of LDL-C can fully account for this risk.

RECENT FINDINGS

The atherosclerotic risk associated with FH variants is independent of observed adult LDL-C levels. Modeling adult longitudinal LDL-C accounts for more of this risk compared to using a single measurement. Still, even when adjusting for observed longitudinal LDL-C in adult cohorts, FH variant carriers are at increased risk for coronary artery disease. Genetic analyses, observational studies, and clinical trials all suggest that cumulative LDL-C is a critical driver of cardiovascular risk that may not be fully appreciated by routine LDL-C measurements in adulthood. As such, FH variants confer risk independent of adult LDL-C because these variants increase cumulative LDL-C exposure starting from birth.

SUMMARY

Both research and clinical practice focus on LDL-C measurements in adults, but measurements during adulthood do not reflect lifelong cumulative exposure to LDL-C. Genetic assessments may compliment clinical assessments by better identifying patients who have experienced greater longitudinal LDL-C exposure.

Acanthosis Nigricans Is a Strong Predictor of Low Blood Calcidiol Levels in Children and Adolescents

Background: Clinical consensus differs as to when blood vitamin D (VD) levels should be measured in children. Obesity and metabolic syndrome are risk factors for low VD levels and are also associated with acanthosis nigricans (AN). Objectives: To test whether the clinical diagnosis of AN is a strong predictor for vitamin D deficiency (VDD) in children. Methods: Within the study period (2015-2020), we identified 677 consecutive individuals (age <18 years) with available calcidiol measurements and compared those with (n = 273) and without (n = 404) AN. Bivariate associations and the occurrence of AN were tested using the chi-squared test. Multivariate logistic regression was performed to control for confounding variables, and adjusted odds ratios with 95% confidence intervals (CI) were reported. Multiple regression analysis was performed, and unstandardized beta coefficients, standard errors, and standardized beta coefficients were reported. Results: Individuals with AN had 3.6 times higher odds of VDD than those without (95% CI: 1.38-9.51, P = 0.009). Males had 0.41 times lower odds of having AN than females (95% CI: 0.21-0.79, P = 0.008). Individuals with vitamin D sufficiency (VDS) were much less likely to be diagnosed with metabolic syndrome compared with those who were vitamin D deficient (P = 0.011), even after adjusting for body mass index z-scores. Conclusion: Children and adolescents with AN are at a higher risk of VDD and should likely be tested for low calcidiol levels.

Elevated atherogenic lipid profile in youth with bipolar disorder during euthymia and hypomanic/mixed but not depressive states

OBJECTIVE

Abnormal blood lipid levels are common in individuals with bipolar disorder (BD). Previous studies have revealed lipid-mood associations in adults with BD, but no data on this relationship is available in youth populations. This cross-sectional study examined the associations of lipid levels with mood states and symptoms in a cohort of youth with BD.

METHODS

Participants were youth with BD and healthy controls (HCs) between the ages of 13-20 years. We compared the levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), and TG/HDL-C ratio between 4 participant episode groups: BD-euthymic (n = 28), BD-depressed (n = 29) BD-hypomanic/mixed (n = 31), and HCs (n = 89). We also examined for dimensional associations of lipids with mania and depression scores in the overall BD group and within BD episode subgroups.

RESULTS

TG levels were significantly higher in the BD-euthymic group (p = 0.008, d = 0.59) and in the BD-mixed/hypomanic group (p = 0.03, d = 0.44) compared to the HC group. TG/HDL-C ratio was also higher in the BD-euthymic group compared to the HC group (p = 0.01, d = 0.51). No dimensional associations were found between lipids and mood symptom scores in the overall BD group. However, within the BD-mixed/hypomanic subgroup, higher mania scores were associated with higher TG (β = 0.42, p = 0.04), TG/HDL-C ratio (β = 0.59, p = 0.002), and lower HDL-C (β = 0.56 p = 0.002).

CONCLUSIONS

Youth with BD demonstrate atherogenic lipid profiles. Higher atherogenic lipids were associated with hypomanic but, contrasting adult BD studies, not depressive symptoms. Future prospective studies are warranted to evaluate the temporal association between lipids and mood among youth with BD.

Levels of Lipid Parameters in Children with Arterial Ischemic Stroke and Headache: Case-Control Study and Meta-Analysis

Background: Abnormalities in levels of lipid parameters are one of the main causes of cardiovascular and cerebrovascular disease in adults. There are limited data on the role of disturbances of lipid metabolism in the etiopathogenesis of arterial ischemic stroke (AIS) in children and the results provided are ambiguous. The aim of the study was to compare the levels of lipid parameters (total cholesterol [TC], triglycerides [TG], high-density lipoprotein [HDL] and low-density lipoprotein [LDL]) between children with AIS, children with headache and healthy children. In addition, we performed meta-analysis of available data on lipid parameters in young patients with AIS. Methods: We retrospectively analyzed 218 children hospitalized between 2002 and 2018 in the Upper-Silesian Child’s Health Center (n = 82 children with AIS, n = 45 children with headache, n = 91 healthy children) with available data on lipid levels, i.e., TC, TG, and HDL. The levels of LDL, non-HDL cholesterol, and a very-low density lipoprotein (VLDL) were calculated. The ratios of TC/HDL, TG/HDL and LDL/HDL were also assessed. Data between cases and controls were analyzed using STATISTICA 13.0 whereas meta-analysis was performed with RevMan version 5.4 software. Results: Children with headache were significantly older than children with AIS (p = 0.001). Ten percent of children with AIS had posterior stroke. The mean TC level was significantly higher in the AIS children than in controls or in children with headache. Mean TG and VLDL levels were significantly different between all groups (p < 0.001 each). The hypertriglyceridemia was more prevalent in AIS children than in children with headache (39% vs. 13%, OR = 4.16 95% CI 1.58–10.94, p = 0.004). Similarly, the frequency of dyslipidemia was higher in children with AIS compared to children with headache (38% vs. 22%, OR = 2.13 95% CI 0.93–4.89, p = 0.078). The meta-analysis was conducted based on data from 4 studies (3 studies published previously plus the results we obtained in the present case-control analysis) with total number of 236 young patients with AIS and 272 healthy controls. Significant Standard Mean Difference (SMD) was found in triglycerides level between young patients with AIS and controls (0.78 95%CI 0.30–1.26 p = 0.002). Conclusions: Lipid abnormalities, especially levels of triglycerides, seem to be of particular importance in children with AIS, as confirmed in meta-analysis. The results of the present study may be a significant contribution to the further research on the role of lipid metabolism disorders in the development of childhood stroke.

Presenting Health Status in Children Using a Radar Plot

BACKGROUND

To try out the feasibility of presenting the health status of children 6 to 12 years old by using radar plots.

METHODS

With data from the Health Oriented Pedagogical Project (HOPP) we have described the health status for 1340 children aged 6 to 12 years. We collected or calculated: stature, body mass, waist circumference, waist to height ratio, high density lipoprotein (HDL) and total cholesterol concentration, blood pressure, accelerometer assessed physical activity, endurance interval running performance, and quality of life. Pertinent variables were presented through a radar plot for both individual cases and groups.

RESULTS

The boys showed better endurance and recorded more moderate to vigorous physical activity than the girls. The activity level dropped from age 6 to age 12 for both sexes. The girls showed a lower systolic blood pressure compared with boys. Self-rated quality of life was high among boys and girls.

CONCLUSIONS

This cohort showed good health and the radar plot made it easy to visualise health status for groups and individuals.

Associations between lipid profiles of adolescents and their mothers based on a nationwide health and nutrition survey in South Korea

OBJECTIVES

Dyslipidaemia is a metabolic disease influenced by environmental and genetic factors. Especially, family history related to genetic background is a strong risk factor of lipid abnormality. The aim of this study is to evaluate the association between the lipid profiles of adolescents and their mothers.

DESIGN

A cross-sectional study.

SETTING

The data were derived from the Korea National Health and Nutrition Examination Survey (IV-VI) between 2009 and 2015.

PARTICIPANTS

2884 adolescents aged 12-18 years and their mothers were included.

PRIMARY OUTCOME MEASURES

Outcome variables were adolescents' lipid levels. Mothers' lipid levels were the interesting variables. The lipid profiles included total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). We identified partial correlation coefficients (r) between the lipids. Multiple linear regressions were performed to identify the amount of change in adolescents' lipid levels for each unit increase of their mothers' lipids. The regression models included various clinical characteristics and health behavioural factors of both adolescents and mothers.

RESULTS

The mean levels of adolescents' lipids were 156.6, 83.6, 50.4 and 89.4 mg/dL, respectively for TC, TG, HDL-C and LDL-C. Positive correlations between lipid levels of adolescents and mothers were observed for TC, TG, HDL-C and LDL-C (r, 95% CI: 0.271, 0.236 to 0.304; 0.204, 0.169 to 0.239; 0.289, 0.255 to 0.322; and 0.286, 0.252 to 0.319). The adolescent TC level was increased by 0.23 mg/dL for each unit increase of the mother's TC (SE, 0.02; p<0.001). The beta coefficients were 0.16 (SE, 0.01), 0.24 (SE, 0.02) and 0.24 (SE, 0.02), respectively, in each model of TG, HDL-C and LDL-C (all p<0.001). The linear relationships were significant regardless of sex and mother's characteristics.

CONCLUSIONS

Mothers' lipid levels are associated with adolescents' lipids; therefore, they can serve as a reference for the screening of adolescent's dyslipidaemia.

Longitudinal changes of lipid profile in the Lebanese pediatric population

Background

Few studies looked at the prevalence of dyslipidemia in pediatric Middle-Eastern countries. In addition, worldwide longitudinal changes of lipid profile is not well documented. The purpose of this study is to look at the longitudinal changes of lipid parameters in Lebanese school-age children.

Materials and methods

A total of 97 subjects (41 girls and 56 boys) aged between 11 and 21 years were included in this study. The subjects were selected among 339 school-age children with a previous abnormal lipid profile who were recruited from 10 schools of varying socio-economic levels (SEL). A fasting lipid profile [total cholesterol (TC), triglycerides (TG) and HDL-cholesterol (HDL-C)] was performed. Non-HDL-cholesterol (Non-HDL-C) was calculated. Weight and height were measured under the same conditions, and BMI percentiles were calculated. A multivariate covariance analysis model (MANCOVA) was used with TG, HDL-C and non-HDL-C as dependent variables with additional post-MANCOVA F tests.

Results

The age of the current cohort is 16.5 ± 2.9 years with no significant difference according to gender. The current lipid profile was obtained 3.1 ± 0.7 years following the initial one, with 53.6% of the subjects having it normalized. TC, TG, and non-HDL-C decreased significantly over time in girls, while only TG decreased significantly in boys. No significant changes were observed for HDL-C. Using MANCOVA, a significant time by age interaction was observed (p < 0.0001), while gender, BMI and SEL were found not to be significant. Post-hoc F tests showed that the time by age interaction was driven by TG (p = 0.03) and non-HDL-C (p < 0.001), the larger effect being observed in younger children.

Conclusion

A high proportion of school-age children normalize their abnormal lipid profile with time. Screening for lipid disorders could be postponed until post puberty age.

Percentile curves for cardiometabolic disease markers in Canadian children and youth: a cross-sectional study

Background

The objective of this study to develop percentile curves for cardiometabolic disease markers in a population-based sample of Canadian children and youth.

Methods

The analysis used data from 6116 children and adolescents between 6 and 19 years of age who participated in the Canadian Health Measures Survey cycles 1 (2007/2009), 2 (2009/2011), and 3 (2012/2013). Total cholesterol, HDL cholesterol, and hemoglobin A1c levels as well as fasting levels of triglycerides, insulin, and homeostasis model assessment insulin resistance were measured using standardized procedures. Age- and sex-specific centiles for all markers were calculated using Cole and Green’s LMS method.

Results

With the exception of hemoglobin A1c, all markers showed age- and sex-related differences during childhood and adolescence.

Conclusions

We have developed centile curves for cardiometabolic disease markers in Canadian children and adolescents and demonstrated age and sex differences that should be considered when evaluating these markers in this age group.

Dyslipidemia in Children With Arterial Ischemic Stroke: Prevalence and Risk Factors

BACKGROUND

Risk factors for pediatric stroke are poorly understood and require study to improve prevention. Total cholesterol and triglyceride values peak to near-adult levels before puberty, a period of increased stroke incidence. The role of lipids in childhood arterial ischemic stroke has been minimally investigated.

METHODS

We performed a cross-sectional analysis of lipid and Lp(a) concentrations in children with arterial ischemic stroke in the International Pediatric Stroke Study to compare the prevalence of dyslipidemia and high- or low-ranking lipid values in our dataset with reported population values. We analyzed sex, body mass index, race, ethnicity, family history, and stroke risk factors for associations with dyslipidemia, high non-high-density lipoprotein cholesterol, and hypertriglyceridemia.

RESULTS

Compared with the National Health and Nutrition Examination Survey, a higher proportion of children ≥5 years with arterial ischemic stroke had dyslipidemia (38.4% versus 21%), high total cholesterol (10.6% versus 7.4%), high non-high-density lipoprotein cholesterol (23.1% versus 8.4%), and low high-density lipoprotein cholesterol (39.8% versus 13.4%). The lipid values that corresponded to one standard deviation above the mean (84th percentile) in multiple published national studies generally corresponded to a lower ranking percentile in children aged five years or older with arterial ischemic stroke. Dyslipidemia was more likely associated with an underweight, overweight, or obese body mass index compared with a healthy weight. Ethnic background and an acute systemic illness were also associated with abnormal lipids.

CONCLUSIONS

Dyslipidemia and hypertriglyceridemia may be more prevalent in children with arterial ischemic stroke compared with stroke-free children.

Distinct Lipoprotein Curves in Normal Weight, Overweight, and Obese Children and Adolescents

OBJECTIVES

Pediatric lipoprotein curves are based on population-based samples. As obesity, may alter lipoprotein levels, cutoffs not adjusted for body mass index (BMI) are potentially inappropriate. We aimed to develop distinct serum lipid curves based on sex- and BMI-percentiles for children and adolescents.

METHODS

Cross-sectional analysis included all healthy children and adolescents (age range 2-17 years) with available serum lipid concentrations (n = 152,820 of approximately 1.2 million children and adolescents per study year). These children and adolescents were categorized according to sex- and age-stratified BMI-percentiles: 100,375 normal weight (5th-85th percentile), 26,028 overweight (85th-95th percentile) and 26,417 obese (≥95th percentile) individuals. Excluded were individuals with hyperlipidemia, gastrointestinal disease, thyroid disease and lipid-lowering medications. Lambda-Mu-Sigma, smoothed percentile lipid curves were computed.

RESULTS

Obese children had a lipid profile pattern throughout childhood and adolescence similar to that of normal weight subjects but with a significant upward shift in total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), and triglycerides (TGs) and a downward shift in high-density lipoprotein-cholesterol (HDL-C). Obese boys had 13 mg/dL higher TC levels (P < 0.001), 11 mg/dL higher LDL-C levels, 15 mg/dL higher non-HDL-C levels, and 5 mg/dL lower HDL-C levels (P < 0.001). Obese girls had 6 mg/dL higher TC levels, 7 mg/dL higher LDL-C levels, 11 mg/dl higher non-HDL-C levels, and 6 mg/dL lower HDL-C levels (P < 0.001).

CONCLUSIONS

Across a large, nationally representative cohort of children and adolescents, lipoprotein levels were found to vary in relation to weight status. On the basis of these findings, it is suggested that when evaluating the lipid profile in the pediatric population, in addition to sex-based curves, clinical decision making may require consideration of BMI-stratified curves.

Reference Values for The Triglyceride to High-Density Lipoprotein Cholesterol Ratio and Non-High-Density Lipoprotein Cholesterol in Korean Children and Adolescents: The Korean National Health and Nutrition Examination Surveys 2007-2013

Aim: Cholesterol levels vary throughout childhood and adolescence. The aim of the present study was to evaluate and identify age- and gender-specific reference values for serum lipid concentrations including non-high-density lipoprotein cholesterol (non-HDL-C) and the triglyceride to HDL-C ratio (TG/HDL-C ratio) in apparently healthy Korean children and adolescents.

Methods: A total of 6197 participants aged 10 to 19 years old from the 2007–2013 Korean National Health and Nutrition Examination Survey were analyzed. Serum lipid concentrations were evaluated according to age and gender.

Results: The overall mean concentration of non-HDL-C was 105.5 ± 25.6 mg/dL, with a significant gender difference: 103.3 ± 26.1 mg/dL in boys and 107.9 ± 24.7 mg/dL in girls (p = 0.028). The median values of non-HDL-C concentrations in boys and girls, respectively, were 111 and 112 mg/dL in the 10-year-old age group, 95 and 103 mg/dL in the 15-year-old age group, and 109 and 103 mg/dL in the 19-year-old age group. The overall mean TG/HDL-C ratio was 1.74 ± 1.22, and there were no significant gender differences: 1.77 ± 1.25 in boys and 1.72 ± 1.22 in girls (p = 0.183). The median values of the TG/HDL-C ratio in boys and girls were 1.16 and 1.00 in the 10-year-olds, 1.54 and 0.95 in the 15-year-olds, and 1.74 and 0.84 in the 19-year-olds, respectively.

Conclusions: Age- and gender-specific reference values for non-HDL-C and for the TG/HDL-C ratio in children and adolescents could provide valuable information for individualized interpretations of lipid profiles and interventions as well as for strategies to prevent and manage childhood and adolescent dyslipidemia.

Physical activity and cardiovascular risk factors in children: meta-analysis of randomized clinical trials

OBJECTIVE

To assess the effects of physical activity interventions in preventing cardiovascular risk factors in childhood through a systematic review and meta-analysis of randomized clinical trials (RCTs).

METHODS

A search of online databases (PubMed, EMBASE and Cochrane CENTRAL) was conducted from inception until June 2013. RCTs enrolling children 6-12years old conducted physical activity interventions longer than 6months, assessing their effect on body mass index (BMI), systolic (SBP) and diastolic blood pressure (DBP), total cholesterol (TC) and triglycerides (TG) were included. Data analysis was performed using a random-effects model.

RESULTS

Of 23.091 articles retrieved, 11 RCTs (10.748 subjects) were included. Physical activity interventions were not associated with reductions of BMI [-0.03kg/m(2) (95%CI -0.16, 0.13) I(2) 0%]. However, there was an association between the interventions and reduction of SBP [-1.25mmHg (95%CI -2.47, -0.02) I(2) 0%], DBP [-1.34mmHg (95%CI -2.57, -0.11) I(2) 43%] and TG [-0.09mmol/L (95%CI -0.14, -0.04) I(2) 0%], and increase of TC [0.14mmol/L (95%CI 0.01, 0.27) I(2) 0%].

CONCLUSION

As physical activity intervention programs lasting longer than 6months are associated with reductions in blood pressure levels and triglycerides, they should be considered to be included in prevention programs for cardiovascular diseases in schoolchildren.

Predictors of cholesterol and lipoprotein(a) testing in children with arterial ischemic stroke

BACKGROUND

Professional societies recommend screening lipids in healthy children. Dyslipidemia and elevated lipoprotein(a) are risk factors for adult cardiovascular disease and stroke. Their role in childhood arterial ischemic stroke is unexplored. Inconsistencies in testing limit analysis of existing lipid data. The objective of this study is to identify predictors and modifiable barriers to lipid testing in pediatric stroke.

METHODS

In this cross-sectional analysis, children (28 days-18 years) with arterial ischemic stroke were identified from the International Pediatric Stroke Study registry (January 2003-April 2012). Analyzed predictors of recorded lipid or lipoprotein a (Lp(a)) testing were age, sex, race, ethnicity, body mass index (BMI) category, other stroke risk factors, country, US region, and recurrent thrombosis.

RESULTS

Among 1652 participants (median, 6 years [interquartile range, 1.7-12.7]; 59.0% male; 40.8% white; 7.0% black), at least 1 lipid parameter or Lp (a) was available for 461 (27.9%). Compared with infants, testing was incrementally higher for older age categories. Compared with whites, testing was lower in blacks (adjusted odds ratio [OR], .5; 95% confidence interval [CI], .4-.5; P < .0001). Hispanic ethnicity only predicted testing within the United States (OR, 2.2; 95% CI, 1.4-3.4; P = .001]. Testing was lower in the United States and Australia and higher in Chile. Any thrombotic recurrence and recurrent symptomatic arterial ischemic stroke were associated with testing, unlike male sex, BMI, other stroke risk factors, and region in the United States.

CONCLUSIONS

Only a quarter of children with stroke had recorded lipid testing. Older age, white race, and recurrence predicted testing. In future study adjusting for these predictors may be necessary. Standardized lipid testing in children with arterial ischemic stroke may further our understanding of this potential risk factor.

Efficacy and safety of tocilizumab in patients with polyarticular-course juvenile idiopathic arthritis: results from a phase 3, randomised, double-blind withdrawal trial

Objective

To evaluate the interleukin-6 receptor inhibitor tocilizumab for the treatment of patients with polyarticular-course juvenile idiopathic arthritis (pcJIA).

Methods

This three-part, randomised, placebo-controlled, double-blind withdrawal study (NCT00988221) included patients who had active pcJIA for ≥6 months and inadequate responses to methotrexate. During part 1, patients received open-label tocilizumab every 4 weeks (8 or 10 mg/kg for body weight (BW) <30 kg; 8 mg/kg for BW ≥30 kg). At week 16, patients with ≥JIA-American College of Rheumatology (ACR) 30 improvement entered the 24-week, double-blind part 2 after randomisation 1:1 to placebo or tocilizumab (stratified by methotrexate and steroid background therapy) for evaluation of the primary end point: JIA flare, compared with week 16. Patients flaring or completing part 2 received open-label tocilizumab.

Results

In part 1, 188 patients received tocilizumab (<30 kg: 10 mg/kg (n=35) or 8 mg/kg (n=34); ≥30 kg: n=119). In part 2, 163 patients received tocilizumab (n=82) or placebo (n=81). JIA flare occurred in 48.1% of patients on placebo versus 25.6% continuing tocilizumab (difference in means adjusted for stratification: −0.21; 95% CI −0.35 to −0.08; p=0.0024). At the end of part 2, 64.6% and 45.1% of patients receiving tocilizumab had JIA-ACR70 and JIA-ACR90 responses, respectively. Rates/100 patient-years (PY) of adverse events (AEs) and serious AEs (SAEs) were 480 and 12.5, respectively; infections were the most common SAE (4.9/100 PY).

Conclusions

Tocilizumab treatment results in significant improvement, maintained over time, of pcJIA signs and symptoms and has a safety profile consistent with that for adults with rheumatoid arthritis.

Trial registration number:

NCT00988221.

C-type natriuretic peptide plasma levels are reduced in obese adolescents

The high prevalence of obesity in children may increase the magnitude of lifetime risk of cardiovascular disease (CD). At present, explicit data for recommending biomarkers as routine pre-clinical markers of CD in children are lacking. C-type natriuretic peptide (CNP) is assuming increasing importance in CD; in adults with heart failure, its plasma levels are related to clinical and functional disease severity. We have previously reported five different reference intervals for blood CNP as a function of age in healthy children; however, data on plasma CNP levels in obese children are still lacking. Aim of this study was to assess CNP levels in obese adolescents and verify whether they differ from healthy subjects. Plasma CNP was measured in 29 obese adolescents (age: 11.8 ± 0.4 years; BMI: 29.8 ± 0.82) by radioimmunoassay and compared with the reference values of healthy subjects. BNP was also measured. Both plasma CNP and BNP levels were significantly lower in the obese adolescents compared to the appropriate reference values (CNP: 3.4 ± 0.2 vs 13.6 ± 2.3 pg/ml, p<0.0001; BNP: 18.8 ± 2.6 vs 36.9 ± 5.5 pg/ml, p=0.003). There was no significant difference between CNP values in males and females. As reported in adults, we observed lower plasma CNP and BNP levels in obese children, suggesting a defective natriuretic peptide system in these patients. An altered regulation of production, clearance and function of natriuretic peptides, already operating in obese adolescents, may possibly contribute to the future development of CD. Thus, the availability of drugs promoting the action of natriuretic peptides may represent an attractive therapeutic option to prevent CD.

Review of lipid and lipoprotein(a) abnormalities in childhood arterial ischemic stroke

National organizations recommend cholesterol screening in children to prevent vascular disease in adulthood. There are currently no recommendations for cholesterol and lipoprotein (a) testing in children who experience an arterial ischemic stroke. While dyslipidemia and elevated lipoprotein (a) are associated with ischemic stroke in adults, the role of atherosclerotic risk factors in childhood arterial ischemic stroke is not known. A review of the literature was performed from 1966 to April 2012 to evaluate the association between childhood arterial ischemic stroke and dyslipidemia or elevated lipoprotein (a). Of 239 citations, there were 16 original observational studies in children (with or without neonates) with imaging-confirmed arterial ischemic stroke and data on cholesterol or lipoprotein (a) values. Three pairs of studies reported overlapping subjects, and two were eliminated. Among 14 studies, there were data on cholesterol in 7 and lipoprotein (a) in 10. After stroke, testing was performed at >three-months in nine studies, at ≤three-months in four studies, and not specified in one study. There were five case-control studies: four compared elevated lipoprotein (a) and one compared abnormal cholesterol in children with arterial ischemic stroke to controls. A consistent positive association between elevated lipoprotein (a) and stroke was found [Mantel-Haenszel OR 4·24 (2·94-6·11)]. There was no association in one study on total cholesterol, and a positive association in one study on triglycerides. The literature suggests that elevated lipoprotein (a) may be more likely in children with arterial ischemic stroke than in control children. The absence of confirmatory study on dyslipidemia should be addressed with future research.