Familial Hypercholesterolemia and Its Current Diagnostics and Treatment Possibilities: A Literature Analysis

Pharmacokinetic Drug-Drug Interaction between Cilostazol and Rosuvastatin in Healthy Participants

BACKGROUND AND OBJECTIVES

Cilostazol improves ischemic symptoms and prevents recurrence following cerebral infarction, and rosuvastatin reduces cholesterol levels. However, no reports exist on the pharmacokinetic interactions between these two drugs in healthy adults. This study evaluated the pharmacokinetic (PK) interactions and safety of cilostazol and rosuvastatin when co-administered to healthy male participants.

METHODS

A randomized, open-label, multiple-dosing, two-arm, two-period study was conducted. Arm A had 30 participants receiving 200 mg cilostazol daily and arm B had 27 participants receiving 20 mg rosuvastatin daily for 7 days. In period 2, both arms received a combination of 200 mg cilostazol and 20 mg rosuvastatin daily for 7 days following a 7-day washout period. Plasma concentrations of cilostazol, its metabolites, and rosuvastatin were quantified using liquid chromatography-tandem mass spectrometry.

RESULTS

Fifty-seven participants were randomized, and 44 completed the study. The geometric mean ratio (GMR) and 90% confidence intervals (CI) for maximum plasma concentration at steady state (Cmax,ss) and area under the plasma concentration-time curve during the dosing interval at steady state (AUCtau,ss) indicated no significant interaction between cilostazol and rosuvastatin. Safety assessments showed comparable profiles to individual drug administration, with no significant adverse events.

CONCLUSION

The repeated co-administration of cilostazol and rosuvastatin in healthy male participants resulted in minor PK interactions and exhibited a safety and tolerability profile similar to those of the individual drugs. This suggested that the combined regimen is well tolerated and does not necessitate dose adjustments.

REGISTRATION

ClinicalTrials.Gov identifier no. NCT06568133.

Coagulation in familial hypercholesterolemic patients: effect of current hypolipidemic treatment and anticoagulants

Familial hypercholesterolemia (FH) is a relatively rare genetic disease associated with high serum cholesterol levels but also with abnormalities in blood coagulation. Novel pharmacotherapeutic approaches in FH including proprotein convertase subtilisin/kexin type 9 antibodies (PCSK9Ab) are very efficient in decreasing cholesterol levels but their impact on coagulation in FH is not yet established. Therefore, we hypothesized that these novel antidyslipidemic drugs can positively impact blood coagulation due to their more potent effect on cholesterol. A total of 15 healthy volunteers and all 15 available patients with severe FH treated at the University Hospital Hradec Králové were enrolled, coagulation was assessed by mechanic coagulometer, and the impact of four clinically used direct anticoagulants was analyzed ex vivo. FH patients were treated effectively as their total cholesterol was 4.11 ± 1.57 mM and LDL cholesterol was 2.44 ± 1.46 mM, which were even lower values than detected in our generally healthy controls. Twelve from the 15 FH patients were finally analyzed as 3 were treated with anticoagulants. Coagulation in FH patients was prolonged more extensively by dabigatran and rivaroxaban, when compared to healthy controls. Treatment with PCSK9Ab or lipid apheresis did not seem to have a significant effect on coagulation. The latter procedure however significantly decreased serum levels of one vitamin K form, MK4. Shorter coagulation time was associated with higher levels of LDL, non-HDL, and total cholesterol. Current treatment of FH seems to improve the effects of direct anticoagulants beyond known effects on LDL cholesterol levels.

Enhanced Hypercoagulability Using Clot Waveform Analysis in Patients with Acute Myocardial Infarction and Acute Cerebral Infarction

Background: Routine activated partial thromboplastin time (APTT) and prothrombin time (PT) measurements do not indicate hypercoagulability in patients with acute myocardial infarction (AMI) and acute cerebral infarction (ACI). Methods: Hypercoagulability in patients with AMI or ACI was evaluated using a clot waveform analysis of the APTT or a small amount of tissue factor activation assay (sTF/FIXa). In the CWA, the derivative peak time (DPT), height (DPH), width (DPW), and area the under the curve (AUC) were evaluated. Results: The APTT did not indicate hypercoagulability, but the second DPT of CWA-sTF/FIXa was significantly shorter in patients with ACI than in healthy volunteers (HVs). The first DPH values of CWA-APTT and CWA-sTF/FIXa in patients with ACI and AMI were significantly higher than in HVs. In the receiver operating characteristic (ROC) analyses of ACI or AMI vs. non-thrombosis, the AUC was >0.800 in the DPHs of CWA-APTT and CWA-sTF/FIXa. The AUC of CWA-APTT and CWA-sTF/FIXa in patients with AMI and ACI was significantly higher than in HVs. The AUC/second DPT of CWA-APTT and CWA-sTF/FIXa in patients with AMI and ACI was significantly higher than in HVs. Regarding the ROC analyses of ACI or AMI vs. HVs, the AUC of ROC was higher than 0.800 in the AUC and AUC/second DPT of CWA-APTT and CWA-sTF/FIXa. Conclusions: The AUC/second DPT of CWA-APTT and CWA-sTF/FIXa may be a useful parameter for detecting a hypercoagulable state in patients with AMI and ACI.

Targeted NGS Revealed Pathogenic Mutation in a 13-Year-Old Patient with Homozygous Familial Hypercholesterolemia: A Case Report

Familial hypercholesterolemia is an autosomal hereditary disease defined by an increased level of low-density lipoprotein cholesterol (LDL-C), which predisposes significant risks for premature cardiovascular disorders. We present a family trio study: proband, a 13-year-old Kazakh girl with homozygous familial hypercholesterolemia (HoFH) and her parents. HoFH is much more rare and severe than a heterozygous form of the disorder. HoFH patients generally present with LDL-C levels exceeding 13 mmol/L, resulting in early and life-threatening cardiovascular events within the first decades of life. In cases of neglected treatment, young patients have a risk of death from coronary diseases before the age of 30. The aim of this research was to identify genetic mutations in the affected patient and her parents. Genetic testing was necessary due to highly elevated LDL-C levels and the presence of multiple xanthomas. Targeted next-generation sequencing (NGS) was performed in this study using the Illumina TruSight cardio panel, which targets 174 genes related to cardiac disorders. The girl was diagnosed with HoFH based on the results of genetic testing. A biallelic mutation was observed in exon 3 of the low-density lipoprotein receptor (LDLR): c. 295 G>A (p.Glu99Lys). Sanger sequencing confirmed that the mutant gene was inherited from both parents. After confirming the genetic diagnosis of HoFH, the patient was treated with LDL apheresis and statins. This case report is the first study of HoFH in a pediatric patient from the Central Asian region. Globally, it emphasizes the need for increased clinical awareness among healthcare providers, as early detection and intervention are important for improving outcomes, particularly in pediatric patients with this rare genetic disorder.

Early-onset familial hypercholesterolemia: A case of extensive xanthomas and premature coronary artery disease

Key Clinical Message

Early recognition and management of familial hypercholesterolemia (FH) are crucial, especially in patients with extensive xanthomas and premature coronary artery disease. Prompt diagnosis and aggressive lipid-lowering therapy can significantly reduce morbidity and mortality rates. Careful clinical assessment in resource-limited settings is essential for optimal outcomes.

Abstract

Familial hypercholesterolemia (FH) is an autosomal dominant inherited disorder that causes chronically elevated levels of low-density lipoprotein (LDL) cholesterol. Based on LDL levels, FH can be heterozygous or homozygous, further established through clinical features, laboratory findings, and genetic analysis. Elevated cholesterol levels cause atherosclerosis, coronary artery disease, myocardial infarction, and sudden death. Xanthomas are a clinical manifestation of FH that reveal the underlying systemic genetic disease. We present the case of a 47-year-old male with triple vessel coronary artery disease and widespread xanthomas, diagnosed with homozygous FH based on "The Dutch Lipid Clinic Network Diagnostic Criteria for Familial Hypercholesterolemia." Lifelong therapy with lipid-lowering medications and lifestyle changes is necessary in such cases.

Complex Coronary Artery Lesions in a Young Woman With an Acute Myocardial Infarction and Genetically Confirmed Familial Hypercholesterolemia: A Case Report and Literature Review From a Developing Country

Familial hypercholesterolemia (FH) is a genetic disorder characterized by elevated levels of low-density lipoprotein cholesterol (LDL-C) in the blood from an incredibly early age. This condition leads to the early development of atherosclerotic arterial diseases, which can manifest even in the first few decades of life. Mutations in genes related to the LDL receptor (LDL-R), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin type 9 (PCSK9) are the main molecular mechanisms causing familial hypercholesterolemia. This case involves a 44-year-old Vietnamese female who presented at the emergency department with chest pain and was diagnosed with acute myocardial infarction (AMI) complicated by cardiogenic shock. Clinical signs and an elevated LDL-C level pointed to prolonged exposure to high cholesterol. A Dutch Lipid Clinic Network (DLCN) score of 10 further supported the diagnosis of FH. The reverse T-stenting and small protrusion (TAP) technique was selected and successfully employed to stent the LMCA, left anterior descending artery (LAD) and left circumflex artery (LCx). This technique was chosen due to its simplicity and rapid execution, making it particularly suitable in situations of cardiogenic shock where time-consuming procedures should be avoided. Genetic testing confirmed a heterozygous pathogenic mutation in the LDL-R gene, corroborating the clinical diagnosis of FH. The patient's condition has gradually stabilized, and they have been discharged from the hospital. The patient is currently being monitored as an outpatient at the cardiology clinic. This case emphasizes the importance of considering FH in patients with premature cardiovascular events by applying the clinical diagnostic criteria and confirming by genetic analysis. It also highlights advanced interventional techniques for managing complex coronary lesions, such as reverse TAP.

Cellular and functional evaluation of LDLR missense variants reported in hypercholesterolemic patients demonstrates their hypomorphic impacts on trafficking and LDL internalization

BACKGROUND

Familial hypercholesterolemia (FH) is an autosomal dominant disorder characterized by increased LDL-cholesterol levels. About 85% of FH cases are caused by LDLR mutations encoding the low-density lipoprotein receptor (LDLR). LDLR is synthesized in the endoplasmic reticulum (ER) where it undergoes post-translational modifications and then transported through Golgi apparatus to the plasma membrane. Over 2900 LDLR variants have been reported in FH patients with limited information on the pathogenicity and functionality of many of them. This study aims to elucidate the cellular trafficking and functional implications of LDLR missense variants identified in suspected FH patients using biochemical and functional methods.

METHODS

We used HeLa, HEK293T, and LDLR-deficient-CHO-ldlA7 cells to evaluate the subcellular localization and LDL internalization of ten LDLR missense variants (p.C167F, p.D178N, p.C243Y, p.E277K, p.G314R, p.H327Y, p.D477N, p.D622G, p.R744Q, and p.R814Q) reported in multiethnic suspected FH patients. We also analyzed the functional impact of three variants (p.D445E, p.D482H, and p.C677F), two of which previously shown to be retained in the ER.

RESULTS

We show that p.D622G, p.D482H, and p.C667F are largely retained in the ER whereas p.R744Q is partially retained. The other variants were predominantly localized to the plasma membrane. LDL internalization assays in CHO-ldlA7 cells indicate that p.D482H, p.C243Y, p.D622G, and p.C667F have quantitatively lost their ability to internalize Dil-LDL with the others (p.C167F, p.D178N, p.G314R, p.H327Y, p.D445E, p.D477N, p.R744Q and p.R814Q) showing significant losses except for p.E277K which retained full activity. However, the LDL internalization assay is only to able evaluate the impact of the variants on LDL internalization and not the exact functional defects such as failure to bind LDL. The data represented illustrate the hypomorphism nature of variants causing FH which may explain some of the variable expressivity of FH.

CONCLUSION

Our combinatorial approach of in silico, cellular, and functional analysis is a powerful strategy to determine pathogenicity and FH disease mechanisms which may provide opportunitites for novel therapeutic strategies.

Evolving Concepts of the SCORE System: Subtracting Cholesterol from Risk Estimation: A Way for a Healthy Longevity?

The role of cholesterol, mainly low-density lipoproteins (LDL-C), as a causal risk factor for atherosclerotic cardiovascular disease (ASCVD) is now established and accepted by the international scientific community. Based on this evidence, the European and American guidelines recommend early risk stratification and "rapid" achievement of the suggested target according to the risk estimation to reduce the number of major cardiovascular events. Prolonged exposure over the years to high levels of LDL-C is one of the determining factors in the development and progression of atherosclerotic plaque, on which the action of conventional risk factors (cigarette smoking, excess weight, sedentary lifestyle, arterial hypertension, diabetes mellitus) as well as non-conventional risk factors (gut microbiota, hyperuricemia, inflammation), alone or in combination, favors the destabilization of the atherosclerotic lesion with rupture/fissuration/ulceration and consequent formation of intravascular thrombosis, which leads to the acute clinical manifestations of acute coronary syndromes. In the current clinical practice, there is a growing number of cases that, although extremely common, are emblematic of the concept of long-term exposure to the risk factor (LDL hypercholesterolemia), which, not adequately controlled and in combination with other risk factors, has favored the onset of major cardiovascular events. The triple concept of "go lower, start earlier and keep longer!" should be applied in current clinical practice at any level of prevention. In the present manuscript, we will review the current evidence and documents supporting the causal role of LDL-C in determining ASCVD and whether it is time to remove it from any score.

Transient second-degree type 2 atrioventricular block after infliximab infusion in a patient with Crohn's disease and heterozygous familial hypercholesterolemia

Current treatments for patients in the active phase of Crohn's disease (CD) include conventional treatments and biological treatments. Infliximab (IFX), a TNF-α antagonist, is recommended to induce remission in patients with moderate-to-severe CD who have not responded to conventional therapy. IFX terminates the inflammatory cascade by inhibiting the nuclear factor-κB (NF-κB), mitogen-activated protein kinase (MAPK), and caspase signaling pathways and increases the apoptosis of activated T cells in inflamed tissues.

Unveiling Familial Hypercholesterolemia-Review, Cardiovascular Complications, Lipid-Lowering Treatment and Its Efficacy

Familial hypercholesterolemia (FH) is a genetic disorder primarily transmitted in an autosomal-dominant manner. We distinguish two main forms of FH, which differ in the severity of the disease, namely homozygous familial hypercholesterolemia (HoFH) and heterozygous familial hypercholesterolemia (HeFH). The characteristic feature of this disease is a high concentration of low-density lipoprotein cholesterol (LDL-C) in the blood. However, the level may significantly vary between the two mentioned types of FH, and it is decidedly higher in HoFH. A chronically elevated concentration of LDL-C in the plasma leads to the occurrence of certain abnormalities, such as xanthomas in the tendons and skin, as well as corneal arcus. Nevertheless, a significantly more severe phenomenon is leading to the premature onset of cardiovascular disease (CVD) and its clinical implications, such as cardiac events, stroke or vascular dementia, even at a relatively young age. Due to the danger posed by this medical condition, we have investigated how both non-pharmacological and selected pharmacological treatment impact the course of FH, thereby reducing or postponing the risk of clinical manifestations of CVD. The primary objective of this review is to provide a comprehensive summary of the current understanding of FH, the effectiveness of lipid-lowering therapy in FH and to explain the anatomopathological correlation between FH and premature CVD development, with its complications.

Familial Hypercholesterolemia: A Literature Review of the Pathophysiology and Current and Novel Treatments

Familial hypercholesterolemia (FH) is a genetically transmitted disorder. It shows an autosomal dominant mode of inheritance. It is a metabolic disorder. Mutation in chromosome 19 leads to this disorder. Chromosome 19 codes data for low-density lipoprotein (LDL) receptor (LDLR). LDLR either reduces increased LDL levels from the circulation or maintains a normal level of LDL. It precipitates the risk of cardiovascular disease at an early age. Characteristic features of FH are elevated levels of LDL in the blood because of sudden changes in LDLR, which causes a decrease in the clearance of LDL from the blood. Plaque gets deposited in the lumen of the arteries, called atherosclerosis, which occurs at an early young age. If both genes are affected then it is homozygous FH (HoFH); such a case is very rare. When a single gene is affected then that condition is known as heterozygous FH (HeFH). HoFH comes up with more severe cardiac disease than HeFH at an early age. The major cause of FH is a mutation in the LDLR gene while other causes include mutation in various genes like apolipoprotein B (apo B), proprotein convertase subtilisin/kexin type 9 (PCSK9), LDLR adaptor protein 1 (LDLRAP 1). In order to prevent cardiovascular crises due to FH, it must be diagnosed early and treated effectively. With increasing research and advances in medical sciences, many kinds of current and novel therapies are emerging that aim to reduce the level of LDL in blood.

Reporting LDL cholesterol results by clinical biochemistry laboratories in Czechia and Slovakia to improve the detection rate of familial hypercholesterolemia

Introduction

This survey aims to assess the implementation of recommendations from the European Atherosclerosis Society (EAS) and the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) by clinical biochemistry laboratories in Czechia and Slovakia in their policies for reporting low-density lipoprotein cholesterol (LDL-C) concentrations.

Materials and methods

The web-based survey was distributed to all 383 Czech and Slovak clinical biochemistry laboratories that measure lipids by external quality assessment provider SEKK. A total of 17 single-answer questions were included. The questionnaire was focused on the detection and decision points in familial hypercholesterolemia (FH). All survey answers were taken into account. The laboratories followed the EFLM and EAS guidelines when they reported an interpretative comment considering FH diagnosis in adults.

Results

A total of 203 (53%) laboratories answered. Only 5% of laboratories added interpretative comments considering FH diagnosis when LDL-C concentrations are above 5.0 mmol/L in adults, and 3% of laboratories added interpretative comments considering FH diagnosis when LDL-C concentrations are above 4.0 mmol/L in children. Only 7% of laboratories reported goals for all cardiovascular risk categories (low, moderate, high, very high). Non-HDL cholesterol concentrations were calculated by 74% of responders. A significant number (51%) of participants did not measure apolipoprotein B, and 59% of laboratories did not measure lipoprotein(a).

Conclusions

Only a small portion of laboratories from Czechia and Slovakia reported high LDL-C results with interpretative comments considering FH diagnosis in adults, the laboratories did not follow the guidelines.

Genetic Testing for Familial Hypercholesterolemia in a Pediatric Group: A Romanian Showcase

Familial hypercholesterolemia (FH) is a genetic disease marked by high levels of LDL-cholesterol. This condition has long-term clinical implications, such as cardiovascular events, that are evident during adult life. Here, we report on a single-center cross-sectional showcase study of genetic testing for FH in a Romanian pediatric group. Genetic testing for FH was performed on 20 Romanian pediatric patients, 10 boys and 10 girls, admitted with LDL-cholesterol levels over 130 mg/mL to the National Institute for Mother and Child Health "Alesssandrescu-Rusescu" in 2020. Genetic testing was performed using the Illumina TruSight Cardio panel. We identified pathogenic/likely pathogenic variants that could explain the phenotype in 5/20 cases. The involved genes were LDLR and APOB. Clinical signs that suggest the diagnosis of FH are scarce for the pediatric patient, although it can be diagnosed early during childhood by lipid panel screening. Prevention could prove lifesaving for some of these patients.

Inclisiran-Safety and Effectiveness of Small Interfering RNA in Inhibition of PCSK-9

Dyslipidemia is listed among important cardiovascular disease risk factors. Treating lipid disorders is difficult, and achieving desirable levels of LDL-cholesterol (LDL-C) is essential in both the secondary and primary prevention of cardiovascular disease. For many years, statins became the basis of lipid-lowering therapy. Nevertheless, these drugs are often insufficient due to their side effects and restrictive criteria for achieving the recommended LDL-C values. Even the addition of other drugs, i.e., ezetimibe, does not help one achieve the target LDL-C. The discovery of proprotein convertase subtilisin/kexin type 9 (PCSK9) discovery has triggered intensive research on a new class of protein-based drugs. The protein PCSK9 is located mainly in hepatocytes and is involved in the metabolism of LDL-C. In the beginning, antibodies against the PCSK9 protein, such as evolocumab, were invented. The next step was inclisiran. Inclisiran is a small interfering RNA (siRNA) that inhibits the expression of PCSK9 by binding specifically to the mRNA precursor of PCSK9 protein and causing its degradation. It has been noticed in recent years that siRNA is a powerful tool for biomedical research and drug discovery. The purpose of this work is to summarize the molecular mechanisms, pharmacokinetics, pharmacodynamics of inclisiran and to review the latest research.