Intima-media Thickness in treated and untreated patients with and without Familial Hypercholesterolemia: a Systematic Review and Meta-analysis

Evolocumab treatment reduces carotid intima-media thickness in paediatric patients with heterozygous familial hypercholesterolaemia

AIM

Children with heterozygous familial hypercholesterolaemia (HeFH) show greater carotid intima-media thickness (cIMT). Evolocumab, a proprotein convertase subtilisin/kexin type 9 inhibitor monoclonal antibody, substantially reduced low-density lipoprotein cholesterol (LDL-C) and modestly reduced lipoprotein(a) in children with HeFH. We investigated evolocumab's effect on cIMT progression.

METHODS

HAUSER-RCT was a randomised, placebo-controlled trial. 157 paediatric patients with FH (age: 10-17 years) and LDL-C >130mg/dL despite statin therapy received monthly evolocumab 420mg or placebo for 24 weeks. Patients who continued into an open-label extension (HAUSER-OLE; n=150) received 80 weeks of monthly evolocumab plus statins. cIMT was measured by B-mode ultrasound scanning of right and left common carotid artery at baseline; week 24 of RCT [day 1 OLE]; and weeks 24, 48, and 80 of OLE. Descriptive analysis of cIMT was a prespecified HAUSER secondary endpoint, and inferential tests reported here were post-hoc.

RESULTS

151 patients had evaluable cIMT summary scores at ≥1 visit. From RCT baseline to week 24, mean cIMT increased by 0.006mm (SD=0.05) with placebo (n=37) and decreased by 0.003mm (SD=0.05) with evolocumab (n=76). From RCT baseline to OLE week 80, mean cIMT summary score decreased by 0.019mm (SD=0.04) and 0.012mm (SD=0.05), respectively, in patients who initially received placebo (n=34, P=0.007) versus receiving evolocumab throughout (n=59, P=0.067). Across patients who received evolocumab in OLE, mean cIMT significantly decreased by 0.011mm (SD=0.05) from OLE day 1 to week 80 (n=94, P=0.034).

CONCLUSIONS

In children with HeFH, evolocumab plus statin treatment up to 104 weeks led to regression in carotid arterial wall thickening.

Evaluation of carotid artery elasticity and its influencing factors in non-obese PCOS patients using a technique for quantitative vascular elasticity measurement

Objectives

To evaluate the intima-media thickness (IMT) and elasticity of the carotid artery in non-obese polycystic ovary syndrome (PCOS) patients using a quantitative technique for vascular elasticity measurement and to explore the influencing factors.

Methods

Sixty non-obese patients without metabolic and cardiovascular diseases who were diagnosed with PCOS in the Women and Children's Hospital of Chongqing Medical University from January to December 2022 were prospectively selected (case group), and 60 healthy volunteers matched for body mass index were included as the control group. Body weight, height, heart rate, blood pressure, and waist-to-hip ratio were recorded. Fasting blood samples were drawn from the elbow vein to measure hormone levels including total testosterone (TT), sex hormone-binding globulin (SHBG), fasting plasma glucose (FPG), fasting insulin (FINS), lipids, and homocysteine (Hcy). The insulin resistance index (HOMA-IR) and free androgen index (FAI) were calculated. Ultrasound elastography was used to measure the IMT and elastic function parameters of the right carotid artery, including vessel diameter, wall displacement, stiffness coefficient, and pulse wave velocity. Differences in various parameters between the two groups were analyzed, and correlations between the carotid stiffness coefficient and other serological indicators were assessed using Spearman correlation analysis.

Results

No significant differences in age, body mass index, heart rate, systolic blood pressure, and diastolic blood pressure were observed between the two groups (all P>0.05), while the waist-to-hip ratio (WHR) was higher in the case group than in the control group (P<0.05).The hormone level serological indicators TT and FAI were higher in the case group than in the control group, and SHBG was lower in the case group than in the control group (all P<0.05). The metabolism-related serum indicators LDL-C, HDL-C, FPG, triglycerides, and total cholesterol levels were not statistically different between the two groups (all P>0.05), and serum FINS, HOMA-IR, and Hcy levels were significantly higher in the case group than in the control group (all P<0.05).No significant difference in carotid artery diameter was observed between the case group and control group (P>0.05). The carotid artery displacement in the case group was significantly smaller than that in the control group (P<0.05), and carotid IMT, hardness coefficient, and pulse wave propagation velocity were greater in the case group than in the control group (all P<0.05). The carotid elastic stiffness coefficient was positively correlated with WHR, TT, SHBG, FAI, FINS, HOMA-IR and Hcy to varying extents and negatively correlated with SHBG.

Conclusion

In non-obese PCOS patients with no metabolic or cardiovascular disease, the carotid stiffness coefficient was increased and correlated with indicators of hyperandrogenism, insulin resistance, and hyperhomocysteinemia.

Familial hypercholesterolemia in children and the importance of early treatment

PURPOSE OF REVIEW

Familial hypercholesterolemia leads to elevated levels of low-density lipoprotein cholesterol (LDL-C) from birth onwards due to a pathogenetic variation in genes in cholesterol metabolism. Early screening to identify and subsequently treat children with familial hypercholesterolemia is crucial to reduce the risk of premature atherosclerotic cardiovascular disease (ASCVD). This review focuses on recent insights in the field of pediatric familial hypercholesterolemia.

RECENT FINDINGS

Screening in childhood and early initiation of optimal lipid-lowering therapy (LLT) have shown promising outcomes in the prevention of ASCVD. In addition, cost-effectiveness research has demonstrated highly favorable results. With the availability of novel therapies, familial hypercholesterolemia has become a well treatable disease.

SUMMARY

Children with familial hypercholesterolemia benefit from early detection and optimal treatment of their elevated LDL-C levels.

Association between Inflammation, Glycocalyx Biomarkers, and Endothelial Function in Children with Hypercholesterolemia

INTRODUCTION

Hypercholesterolemia is a risk factor for premature arteriosclerosis. Inflammation and oxidative stress are thought to contribute to endothelial dysfunction preceding vasculopathy. We investigated the association between inflammation, glycocalyx biomarkers, endothelial function, and vascular parameters in children with hypercholesterolemia.

METHODS

In 22 patients (LDL-cholesterol >130 mg/dL; median age [IQR]: 13 [2.3] years) and 22 controls (13 [2.5] years), tumor necrosis factor-alpha (TNF-α), oxidized cholesterol (oxLDL), and glycocalyx biomarkers (Syndecan-1, Hyaluronan) were measured using immunoassays. Endothelial function was assessed by peripheral arterial tonometry, sublingual glycocalyx and microcirculation by videomicroscopy and carotid intima-media thickness by ultrasound.

RESULTS

OxLDL was significantly higher in patients (78.9 [38.2] vs. 50.3 [16.6] U/L, p = 0.002), whereas all other experimental parameters were comparable between groups. Multivariate analysis revealed a significant association of Syndecan-1 with TNF-α (β = 0.75, p < 0.001) and with hypercholesterolemia (β = 0.31, p = 0.030). The interaction term combining TNF-α and hypercholesterolemia showed a significant effect (p = 0.034). Sex was an independent predictor of endothelial function.

CONCLUSION

The combined effect of hypercholesterolemia and inflammation on glycocalyx perturbation and the impact of sex in the premature development of arteriosclerosis deserve further evaluation. Therapeutic approaches tackling low-grade systemic inflammation may offer potential to prevent or delay progression of cardiovascular disease and cardiovascular complications.

Childhood Screening for Familial Hypercholesterolemia: JACC Review Topic of the Week

Screening for familial hypercholesterolemia (FH) in childhood remains controversial. Existing guidelines offer practitioners conflicting advice despite generally agreeing on the evidence and areas in which evidence is lacking, including a lack of long-term clinical trials demonstrating coronary event reduction as a result of screening and long-term data on statin side effects. A limitation of existing evidence-based frameworks is reliance on 1 evidence grading system to determine recommendations. However, rigorous evidence evaluation alternatives relevant to FH exist. FH is considered a tier 1 genetic condition, meaning that identification and treatment will improve health outcomes among those affected. Elevated low-density lipoprotein cholesterol, the primary consequence of FH, can be considered causal for atherosclerosis and coronary heart disease. Incorporating these concepts into existing evidence pathways allows the inclusion of surrogate clinical trial outcomes (low-density lipoprotein cholesterol reduction and atherosclerosis regression) and observational data on medication safety, strengthening the evidence for pediatric screening for FH.

How Genetic Variants in Children with Familial Hypercholesterolemia Not Only Guide Detection, but Also Treatment

Familial hypercholesterolemia (FH) is a hereditary disorder that causes severely elevated low-density lipoprotein (LDL-C) levels, which leads to an increased risk for premature cardiovascular disease. A variety of genetic variants can cause FH, namely variants in the genes for the LDL receptor (LDLR), apolipoprotein B (APOB), proprotein convertase subtilisin/kexin type 9 (PCSK9), and/or LDL-receptor adaptor protein 1 (LDLRAP1). Variants can exist in a heterozygous form (HeFH) or the more severe homozygous form (HoFH). If affected individuals are diagnosed early (through screening), they benefit tremendously from early initiation of lipid-lowering therapy, such as statins, and cardiovascular imaging to detect possible atherosclerosis. Over the last years, due to intensive research on the genetic basis of LDL-C metabolism, novel, promising therapies have been developed to reduce LDL-C levels and subsequently reduce cardiovascular risk. Results from studies on therapies focused on inhibiting PCSK9, a protein responsible for degradation of the LDLR, are impressive. As the effect of PCSK9 inhibitors (PCSK9-i) is dependent of residual LDLR activity, this medication is less potent in patients without functional LDLR (e.g., null/null variant). Novel therapies that are expected to become available in the near future focused on inhibition of another major regulatory protein in lipid metabolism (angiopoietin-like 3 (ANGPTL3)) might dramatically reduce the frequency of apheresis in children with HoFH, independently of their residual LDLR. At present, another independent risk factor for premature cardiovascular disease, elevated levels of lipoprotein(a) (Lp(a)), cannot be effectively treated with medication. Further understanding of the genetic basis of Lp(a) metabolism, however, offers a possibility for the development of novel therapies.

Integrated guidance to enhance the care of children and adolescents with familial hypercholesterolaemia: Practical advice for the community clinician

Familial hypercholesterolaemia (FH) is a highly penetrant monogenic disorder present from birth that markedly elevates plasma low-density lipoprotein (LDL)-cholesterol (LDL-C) concentration and, if untreated, leads to premature atherosclerosis and coronary artery disease (CAD). At a prevalence of 1:250 individuals, with over 90% undiagnosed, recent estimates suggest that there are approximately 22 000 children and adolescents with FH in Australia and New Zealand. However, the overwhelming majority remain undetected and inadequately treated until adulthood or after their first cardiac event. The guidance in this paper aims to increase awareness about paediatric FH and provide practical advice for the diagnosis and management of FH in children and adolescents. Recommendations are given on the detection, diagnosis, assessment and management of FH in children and adolescents. Recommendations are also made on genetic testing, including counselling and the potential for universal screening programmes. Practical guidance on management includes treatment of non-cholesterol risk factors, and safe and appropriate use of LDL-C lowering therapies, including statins, ezetimibe, PCSK9 inhibitors and lipoprotein apheresis. Models of care for FH need to be adapted to local and regional health care needs and available resources. Targeting the detection of FH as a priority in children and young adults has the potential to alter the natural history of atherosclerotic cardiovascular disease and recognise the promise of early detection for improving long-term health outcomes. A comprehensive implementation strategy, informed by further research, including assessments of cost-benefit, will be required to ensure that this new guidance benefits all families with or at risk of FH.

Effect of Lipoprotein Apheresis on Progression of Carotid Intima-Media Thickness in Patients with Severe Hypercholesterolemia

The extent of intervention effects on carotid intima-media thickness (CIMT) can predict the degree of atherosclerotic cardiovascular risk-reduction. We hypothesized that regular lipoprotein apheresis over the course of 10 years might slow down progression of CIMT in patients with severe hypercholesterolemia. This case series describes 10 Caucasian patients (mean age 60 ± 9 years, 70% female, 80% statin intolerant) with a severe hypercholesterolemia phenotype treated with lipoprotein apheresis between 2005 and 2020 (mean duration, 10 ± 4 years). The median pretreatment low-density lipoprotein cholesterol (LDL-C) level was 214 mg/100 ml (95% confidence interval, 145 to 248), lipoprotein(a) (Lp[a]), 26 mg/100 ml (15 to 109; 40% with Lp(a)>60 mg/100 ml). Three patients were diagnosed with a monogenic cause. The baseline mean CIMT was 850 ± 170 µm, and maximum CIMT was 1,040 ± 220 µm across the age range of 46 to 70 years. Acute effects of lipoprotein apheresis determined as a difference before and immediately after the procedure were estimated as a median of 72 ± 8% and 75 ± 7% reduction in the LDL-C and Lp(a) levels, respectively. Using the imputed trajectories, period-specific on-treatment time-weighted averages for LDL-C and Lp(a) were 141 mg/100 ml (interquartile range, 89 to 152; 38% reduction from the baseline) and 24 mg/100 ml (interquartile range, 12 to 119; 19% reduction from baseline), respectively. The number of patients with CIMT above their "vascular age" decreased from 80% to 30% over the treatment course. In conclusion, an increase in CIMT seen with advanced age and severe hypercholesterolemia was halted with lipoprotein apheresis with an estimated annual rate of change in mean common CIMT of -4 µm/y and maximum CIMT of -3 µm/y.