Biomedical subjects

Jessica Rodenburg

Publications and source records attributed to Jessica Rodenburg.

11 recordsLinked to original sources

PubMed2006

Oxidized low-density lipoprotein in children with familial hypercholesterolemia and unaffected siblings: effect of pravastatin.

OBJECTIVES: To assess the role of oxidized phospholipids (OxPLs) in children with familial hypercholesterolemia (FH) and the effect of pravastatin. BACKGROUND: Oxidized phospholipids are a major component of oxidized low-density lipoprotein (OxLDL) and are bound to lipoprotein (a) [Lp(a)]. The significance of OxPL markers in children is unknown. METHODS: Children with FH were randomized to placebo (n = 88) or pravastatin (n = 90) after instruction on American Heart Association step II diet. Unaffected siblings (n = 78) served as controls. The OxPL content on apolipoprotein B-100 (apoB) detected by antibody E06 (OxPL/apoB ratio), immunoglobulin (Ig)G and IgM immune complexes per apoB (IC/apoB) and on all apoB particles (total apoB-IC = IC/apoB multiplied by plasma apoB levels), autoantibodies to malondialdehyde (MDA)-low-density lipoprotein (LDL), Lp(a), and apoB levels were measured at baseline and after two years of treatment. RESULTS: Compared with unaffected siblings, children with FH had significantly lower levels of OxPL/apoB but higher levels of IgG and IgM total apoB-IC and IgM MDA-LDL autoantibodies. From baseline to two-year follow-up, compared with placebo pravastatin treatment resulted in a greater mean percentage change in apoB (-18.7% vs. 0.3%; p = 0.001), total IgG apoB-IC (-31.9% vs. -12.2%; p < 0.001), and total IgM apoB-IC (-25.5% vs. 13.2%; p = 0.001). Interestingly, pravastatin also resulted in higher OxPL/apoB (48.7% vs. 29.3%; p = 0.028) and Lp(a) levels (21.9% vs. 10.7%; p = 0.044). CONCLUSIONS: Compared with unaffected siblings, children with FH are characterized by elevated levels of apoB-IC and IgM MDA-LDL autoantibodies. Compared with placebo, pravastatin led to a greater reduction in apoB-IC but also to a greater increase in OxPL/apoB and Lp(a), which may represent a novel mechanism of mobilization and clearance of OxPL.

Anticholesteremic Agents↗

PubMed2006

Plant stanols do not restore endothelial function in pre-pubertal children with familial hypercholesterolemia despite reduction of low-density lipoprotein cholesterol levels.

OBJECTIVE: To examine the effect of plant stanols on lipids and endothelial function in pre-pubertal children with familial hypercholesterolemia (FH). STUDY DESIGN: Children with FH (n=42), aged 7-12 years, were enrolled in a double-blind crossover trial, in which they consumed 500 mL of a low-fat yogurt enriched with 2.0 g of plant stanols and 500 mL of a low-fat placebo yogurt for 4 weeks, separated by a 6-week washout period. Lipid profiles and endothelial function were assessed after both consumption periods. Endothelial function was measured as flow-mediated dilation (FMD) of the brachial artery. RESULTS: This daily intake of 2.0 g of stanols significantly decreased the levels of total cholesterol (TC) by 7.5% and low-density lipoprotein cholesterol (LDL-C) by 9.2% as compared with placebo. High-density lipoprotein cholesterol and triglyceride levels remained unaltered. The reduction of LDL-C levels did not improve FMD, which was 10.5%+/-5.1% after plant stanol consumption and 10.6%+/-5.0% after placebo consumption, respectively (P=.852). CONCLUSION: This study demonstrates that plant stanols reduce LDL-C levels in children with FH without improving endothelial function.

Anticholesteremic Agents↗

PubMed2006

Paraoxonase genotype and carotid intima-media thickness in children with familial hypercholesterolemia.

BACKGROUND: Paraoxonase (PON) 1 is a high-density lipoprotein-associated enzyme that may protect against cardiovascular disease. METHOD: We have studied the contribution of PON-1 and PON-2 single nucleotide polymorphisms (SNP; L55M, Q192R and T-107C, S311C) to the intima-media thickness of the common carotid artery in a population of children with classic familial hypercholesterolaemia. RESULTS: The L-variant of the L55M SNP was associated with increased common carotid artery intima-media thickness when compared with the M-variant (P value for trend 0.03). No significant relationship was observed between the other SNP and common carotid artery intima-media thickness. CONCLUSIONS: Our findings suggest that variation at the PON-1 locus contributes to early atherosclerosis in children with familial hypercholesterolaemia.

Adolescent↗

PubMed2005

Low-density lipoprotein receptor genotype and response to pravastatin in children with familial hypercholesterolemia: substudy of an intima-media thickness trial.

BACKGROUND: The lipid-lowering effects of statin therapy show considerable interindividual variation in patients with familial hypercholesterolemia (FH). Whether the type of LDL receptor mutation predicts the response to statin treatment is not yet established. We analyzed the relationship between LDL receptor genotype and response to pravastatin treatment in children with FH using carotid intima-media thickness (IMT) to measure efficacy. METHODS AND RESULTS: In a randomized, placebo-controlled, double-blind, 2-year trial with pravastatin, 193 children had genetically confirmed FH and were included in the present substudy. At baseline, children with null alleles had higher LDL cholesterol levels (difference, 0.94+/-0.19 mmol/L [SEM]; P<0.001) and a greater carotid IMT (difference, 0.019+/-0.01 mm; P=0.02) compared with children with receptor-defective mutations. The decrease in carotid IMT during the trial was not significantly different in children with null alleles and receptor-defective mutations (0.018+/-0.012 and 0.012+/-0.010 mm; 2-way ANCOVA, P=0.7). After 2 years of treatment, the children with null alleles continued to have greater carotid IMT than children with receptor-defective mutations (difference, 0.016+/-0.01 mm; P=0.02). LDL cholesterol lowering tended to be less in carriers of null alleles compared with carriers of receptor-defective mutations (1.30+/-0.25 and 1.85+/-0.20 mmol/L; 2-way ANCOVA, P=0.08). CONCLUSIONS: In FH children, we found that the null allele genotype was associated with a greater carotid IMT, higher LDL cholesterol levels, and a nonsignificant tendency to attenuated LDL cholesterol lowering compared with receptor-defective mutations. Null alleles identify FH patients at the highest cardiovascular disease risk who may benefit from more aggressive treatment started in childhood.

Adolescent↗

PubMed2005

Management of hereditary dyslipidaemia; the paradigm of autosomal dominant hypercholesterolaemia.

Inherited, or autosomal dominant, hypercholesterolaemia, with an average global prevalence of one in 500 individuals, is one of the most frequent inherited metabolic disorders. The disorder is associated with a high risk for premature cardiovascular disease (CVD) and death as a consequence of accelerated atherosclerosis. Although the molecular genetic basis is largely elucidated and effective medical treatment, in the form of inhibitors of intracellular cholesterol synthesis, is available, the disorder is severely underdiagnosed and undertreated. On the other hand, with the well-understood aetiology, the accurate diagnosis, the availability of sensitive predictive makers and efficacious therapy, this disorder can serve as a model for disease management: from early presymptomatic diagnosis, accurate prognosis, optimal treatment and large-scale screening to population-based prevention of CVD.

Dyslipidemias↗

PubMed2004

Effect of low-density lipoprotein receptor mutation on lipoproteins and cardiovascular disease risk: a parent-offspring study.

Studies on the clinical consequences of different low-density lipoprotein (LDL) receptor genotypes in adult patients have yielded conflicting results. We hypothesized that children with familial hypercholesterolemia (FH) provide a better model to perform genotype-phenotype analyses than adults. We tested this hypothesis and assessed the effect of LDL receptor genotypes on lipoprotein levels and on parental risk of cardiovascular disease (CVD) in a pediatric FH cohort. We identified 75 different LDL receptor mutations in 645 children with heterozygous FH; in these children, null alleles were clearly associated with more elevated LDL cholesterol levels compared to receptor-defective mutations. Familial factors explained 50.4% of the variation in LDL cholesterol levels of this pediatric cohort compared to only 9.5% in adults. Parental CVD risk was not significantly different between carriers of null alleles and receptor-defective mutations (RR, 1.22; 95% CI, 0.76-1.95; p=0.4). The N543H/2393del9 mutation was associated with a less deteriorated lipid profile and the parents had less often CVD relative to parents with other mutations (RR, 0.39; 95% CI, 0.20-0.78; p=0.008). We could confirm that children with FH provide a better model to perform genotype-phenotype analyses. In particular, children with null alleles had significantly more elevated LDL cholesterol levels than carriers of other alleles but this was not associated with higher risk of CVD in the parents. Nonetheless, a specific LDL receptor mutation was associated with less deteriorated lipoprotein levels and a milder CVD risk.

Adolescent↗

PubMed2004

Efficacy and safety of statin therapy in children with familial hypercholesterolemia: a randomized controlled trial.

CONTEXT: Children with familial hypercholesterolemia have endothelial dysfunction and increased carotid intima-media thickness (IMT), which herald the premature atherosclerotic disease they develop later in life. Although intervention therapy in the causal pathway of this disorder has been available for more than a decade, the long-term efficacy and safety of cholesterol-lowering medication have not been evaluated in children. OBJECTIVE: To determine the 2-year efficacy and safety of pravastatin therapy in children with familial hypercholesterolemia. DESIGN: Randomized, double-blind, placebo-controlled trial that recruited children between December 7, 1997, and October 4, 1999, and followed them up for 2 years. SETTING AND PARTICIPANTS: Two hundred fourteen children with familial hypercholesterolemia, aged 8 to 18 years and recruited from an academic medical referral center in the Netherlands. INTERVENTION: After initiation of a fat-restricted diet and encouragement of regular physical activity, children were randomly assigned to receive treatment with pravastatin, 20 to 40 mg/d (n = 106), or a placebo tablet (n = 108). MAIN OUTCOME MEASURES: The primary efficacy outcome was the change from baseline in mean carotid IMT compared between the 2 groups over 2 years; the principal safety outcomes were growth, maturation, and hormone level measurements over 2 years as well as changes in muscle and liver enzyme levels. RESULTS: Compared with baseline, carotid IMT showed a trend toward regression with pravastatin (mean [SD], -0.010 [0.048] mm; P =.049), whereas a trend toward progression was observed in the placebo group (mean [SD], +0.005 [0.044] mm; P =.28). The mean (SD) change in IMT compared between the 2 groups (0.014 [0.046] mm) was significant (P =.02). Also, pravastatin significantly reduced mean low-density lipoprotein cholesterol levels compared with placebo (-24.1% vs +0.3%, respectively; P<.001). No differences were observed for growth, muscle or liver enzymes, endocrine function parameters, Tanner staging scores, onset of menses, or testicular volume between the 2 groups. CONCLUSION: Two years of pravastatin therapy induced a significant regression of carotid atherosclerosis in children with familial hypercholesterolemia, with no adverse effects on growth, sexual maturation, hormone levels, or liver or muscle tissue.

Adolescent↗

PubMed2004

Arterial intima-media thickness in children heterozygous for familial hypercholesterolaemia.

Patients with familial hypercholesterolaemia have severe coronary-artery disease early in adult life. Whether lipid-lowering treatment should be started in childhood remains to be established. We therefore assessed 201 children heterozygous for familial hypercholesterolaemia and 80 unaffected siblings (both age ranges 8-18 years) with B-mode ultrasound to measure carotid wall intima-media thickness. Mean combined carotid intima-media thickness of heterozygotes was significantly greater than that of unaffected siblings (0.494 mm [SD 0.051] vs 0.472 [SD 0.049], p=0.002). A significant deviation in intima-media thickness was noted from age 12 years in children with familial hypercholesterolaemia. Findings on multivariate analysis showed LDL cholesterol, age, and sex to be strong and independent predictors of intima-media thickness. Since raised LDL cholesterol concentrations can be lowered efficiently, clinical studies are needed to investigate long-term safety and effectiveness of statin treatment in children with familial hypercholesterolaemia.

Adolescent↗

PubMed2004

Lipid-lowering medications.

In the last decades, there has been an important progression in the development and assessment of various cholesterol-lowering agents. Until recently, in children under age 10, the focus of treatment has been on dietary and lifestyle adjustments. For children older than 10 years, bile acid-binding resins were also recommended if LDL-C levels remained high after dietary adjustment. However, the lipid-lowering effect of bile acid-binding resins is modest at best and long-term compliance is often poor. In contrast, HMG-CoA reductase inhibitors (statins) are currently widely used in adults and are considered the first choice in the treatment of hypercholesterolemia. In the last few years, several randomized trials have shown that statins are also effective in reducing LDL cholesterol levels in children and seem safe at least in the short term. Another novel development is the cholesterol-lowering agent, ezetimibe, which inhibits cholesterol absorption in the intestine. Although efficacy and safety data in children are still lacking, ezetimibe has a good safety profile in adults, either as monotherapy or in combination with a statin. Lastly, two other classes of lipid-lowering drugs include fibrates and nicotinic acid, but most agree that the side effect profile precludes their use in children except in extreme circumstances. Overall, therapeutic options to lower cholesterol levels in children are expanding.

Adult↗

PubMed2003

Family history and cardiovascular risk in familial hypercholesterolemia: data in more than 1000 children.

BACKGROUND: Elevated LDL cholesterol (LDL-C) levels in childhood predict cardiovascular disease (CVD) later in life. Familial hypercholesterolemia (FH) represents the paradigm of this relation. METHODS AND RESULTS: The objectives of this study were to (1) establish the LDL-C level that provides the most accurate diagnosis of FH in children from families with known FH and (2) assess whether lipoprotein variation in these children is associated with premature CVD in relatives. Foremost, however, it was our objective to identify children with FH who are at high risk and in need of early intervention. A total of 1034 consecutive children from FH kindreds were investigated. First, LDL-C levels >3.50 mmol/L had a 0.98 post-test probability (95% CI, 0.96 to 0.99) of predicting the presence of an LDL receptor mutation. Second, children with FH in the highest LDL-C tertile (>6.23 mmol/L) had a 1.7-times higher incidence (95% CI, 1.24 to 2.36) of having a parent with FH suffering from premature CVD (P=0.001). In addition, such a parent was found 1.8 times more often (95% CI, 1.20 to 2.59) among children with FH who had HDL-C <1.00 mmol/L (P=0.004). Last, children with FH whose lipoprotein(a) was >300 mg/L had a 1.45-times higher incidence (95% CI, 0.99 to 2.13) of having a parent with FH suffering from premature CVD (P=0.05). CONCLUSIONS: In FH families, LDL-C levels allow accurate diagnosis of FH in childhood. Moreover, increased LDL-C and lipoprotein(a) and decreased HDL-C levels in children identify FH kindreds with the highest CVD risk.

Adolescent↗

PubMed2003

The apolipoprotein epsilon4 allele confers additional risk in children with familial hypercholesterolemia.

Children with familial hypercholesterolemia (FH) exhibit substantial variance of LDL cholesterol. In previous studies, family members of children with FH were included, which may have influenced results. To avoid such bias, we studied phenotype in 450 unrelated children with FH and in 154 affected sib-pairs. In known families with classical FH, diagnosis was based on plasma LDL cholesterol above the age- and gender-specific 95th percentile. Girls had 0.47 +/- 0.15 mmol/L higher LDL cholesterol, compared with boys (p = 0.002). Also in girls, HDL cholesterol increased by 0.07 +/- 0.03 mmol/L per 5 y (pfor trend = 0.005); this age effect was not observed in boys. The distribution of apolipoprotein (apo) E genotypes was not significantly different between probands, their paired affected siblings, or a Dutch control population. Carriers with or without one epsilon4 allele had similar LDL and HDL cholesterol levels. Within the affected sib-pairs, the epsilon4 allele explained 72.4% of the variance of HDL cholesterol levels (-0.15 mmol/L, 95% confidence interval -0.24 to -0.05, p = 0.003). The effect of apoE4 on HDL cholesterol differed with an analysis based on probands or on affected sib-pairs. The affected sib-pair model used adjustment for shared environment, type of LDL receptor gene mutation, and a proportion of additional genetic factors and may, therefore, be more accurate in estimating effects of risk factors on complex traits. We conclude that the epsilon4 allele was associated with lower HDL cholesterol levels in an affected sib-pair analysis, which strongly suggests that apoE4 influences HDL cholesterol levels in FH children. Moreover, the strong association suggests that apoE4 carries an additional disadvantage for FH children.

Adolescent↗