Familial hypercholesterolemia in Mexico: Initial insights from the national registry

Prevalence and factors associated with possible cases of familial hypercholesterolemia in Brazilian adults: a cross-sectional study

This study aimed to estimate the prevalence of possible cases of FH and analyze associated factors in the adult Brazilian population. Cross-sectional study with laboratory data from the Brazilian National Health Survey, with 8521 participants. Possible cases of FH were defined according to the Dutch Lipid Clinic Network criteria. The prevalence and 95% confidence intervals (95% CI) of possible cases of FH were estimated according to sociodemographic variables, lifestyle, diabetes, hypertension, altered tests, treatment and self-rated health. Logistic regression was used to analyze the associations. The prevalence of possible cases of FH was 0.96%, higher in women, between 45 and 59 years, white race/skin color and others, less education, people with diabetes, hypertension and total cholesterol ≥ 310 mg/dL. The presence of FH was positively associated with regular self-rated health (OR 1.96; 95% CI 0.99-3.84), poor/very poor (OR 3.02; 95% CI 1.30-7.03) and negatively with black race/skin color (OR 0.10; 95% CI 0.02-0.46) and complete elementary school, incomplete high school (OR 0.47; 95% CI 0.23-0.98) and complete high school and more (OR 0.45; 95% CI 0.21-0.95). FH affects 1:104 Brazilian adults, these findings contribute to understanding the burden of disease in Brazil. Due to the scarcity of studies on FH in low- and middle-income countries, further studies are desirable.

A familial hypercholesterolemia registry as the main tool for adequate management of the disease

Familial hypercholesterolemia (FH) is the most common, but poorly diagnosed autosomal-dominant genetic disease which increases the cardio-vascular risk.

AIM

To evaluate the experience of FH registry conducted in Karelia Republic.

METHODS

FH registry in Karelia is existing from 2004, it includes 350 patients with heterozygous FH (110 with definite FH), the mean age is 48 ± 2.3 years. The genetic study was performed in 102 patients (29.1%).

RESULT

The creation of the registry has contributed to the active identification of FH, and now the estimated frequency of FH occurrence in Karelia may be 1:300, in patients with cardiovascular disease 1:10. We also analyzed genetic features of FH in our republic and found that the LDL-C level, above which the probability of LDL receptor mutation increases in Karelia, is 6.5 mmol/L. We analyzed risk factors of ischemic heart disease and the prognosis in FH.

CONCLUSION

The creation and maintenance of a registry is an effective way of organizing timely diagnosis and adequate treatment of FH patients.

Clinical Aspects of Genetic and Non-Genetic Cardiovascular Risk Factors in Familial Hypercholesterolemia

Familial hypercholesterolemia (FH) is the most common monogenic metabolic disorder characterized by considerably elevated low-density lipoprotein cholesterol (LDL-C) levels leading to enhanced atherogenesis, early cardiovascular disease (CVD), and premature death. However, the wide phenotypic heterogeneity in FH makes the cardiovascular risk prediction challenging in clinical practice to determine optimal therapeutic strategy. Beyond the lifetime LDL-C vascular accumulation, other genetic and non-genetic risk factors might exacerbate CVD development. Besides the most frequent variants of three genes (LDL-R, APOB, and PCSK9) in some proband variants of other genes implicated in lipid metabolism and atherogenesis are responsible for FH phenotype. Furthermore, non-genetic factors, including traditional cardiovascular risk factors, metabolic and endocrine disorders might also worsen risk profile. Although some were extensively studied previously, others, such as common endocrine disorders including thyroid disorders or polycystic ovary syndrome are not widely evaluated in FH. In this review, we summarize the most important genetic and non-genetic factors that might affect the risk prediction and therapeutic strategy in FH through the eyes of clinicians focusing on disorders that might not be in the center of FH research. The review highlights the complexity of FH care and the need of an interdisciplinary attitude to find the best therapeutic approach in FH patients.

Diabetes and Familial Hypercholesterolemia: Interplay between Lipid and Glucose Metabolism

Familial hypercholesterolemia (FH) is a genetic disease characterized by high low-density lipoprotein (LDL) cholesterol (LDL-c) concentrations that increase cardiovascular risk and cause premature death. The most frequent cause of the disease is a mutation in the LDL receptor (LDLR) gene. Diabetes is also associated with an increased risk of cardiovascular disease and mortality. People with FH seem to be protected from developing diabetes, whereas cholesterol-lowering treatments such as statins are associated with an increased risk of the disease. One of the hypotheses to explain this is based on the toxicity of LDL particles on insulin-secreting pancreatic β-cells, and their uptake by the latter, mediated by the LDLR. A healthy lifestyle and a relatively low body mass index in people with FH have also been proposed as explanations. Its association with superimposed diabetes modifies the phenotype of FH, both regarding the lipid profile and cardiovascular risk. However, findings regarding the association and interplay between these two diseases are conflicting. The present review summarizes the existing evidence and discusses knowledge gaps on the matter.

Assessment of Associations Between Serum Lipoprotein (a) Levels and Atherosclerotic Vascular Diseases in Hungarian Patients With Familial Hypercholesterolemia Using Data Mining and Machine Learning

Background and aims: Premature mortality due to atherosclerotic vascular disease is very high in Hungary in comparison with international prevalence rates, though the estimated prevalence of familial hypercholesterolemia (FH) is in line with the data of other European countries. Previous studies have shown that high lipoprotein(a)- Lp(a) levels are associated with an increased risk of atherosclerotic vascular diseases in patients with FH. We aimed to assess the associations of serum Lp(a) levels and such vascular diseases in FH using data mining methods and machine learning techniques in the Northern Great Plain region of Hungary.

Methods: Medical records of 590,500 patients were included in our study. Based on the data from previously diagnosed FH patients using the Dutch Lipid Clinic Network scores (≥7 was evaluated as probable or definite FH), we trained machine learning models to identify FH patients.

Results: We identified 459 patients with FH and 221 of them had data available on Lp(a). Patients with FH had significantly higher Lp(a) levels compared to non-FH subjects [236 (92.5; 698.5) vs. 167 (80.2; 431.5) mg/L, p < .01]. Also 35.3% of FH patients had Lp(a) levels >500 mg/L. Atherosclerotic complications were significantly more frequent in FH patients compared to patients without FH (46.6 vs. 13.9%). However, contrary to several other previous studies, we could not find significant associations between serum Lp(a) levels and atherosclerotic vascular diseases in the studied Hungarian FH patient group.

Conclusion: The extremely high burden of vascular disease is mainly explained by the unhealthy lifestyle of our patients (i.e., high prevalence of smoking, unhealthy diet and physical inactivity resulting in obesity and hypertension). The lack of associations between serum Lp(a) levels and atherosclerotic vascular diseases in Hungarian FH patients may be due to the high prevalence of these risk factors, that mask the deleterious effect of Lp(a).

Comorbidities with Familial Hypercholesterolemia (FH): A Systematic Review

Familial hypercholesterolemia (FH) is linked to high levels of low-density lipoprotein cholesterol (LDL-C), atherosclerotic, and aortic stenosis to a lesser extent. We looked at the incidence of prevalent comorbid disorders other than cardiovascular disease (CVD), such as diabetes, chronic kidney disease (CKD), hypertension, and cancer in heterozygous FH (HeFH) patients. PubMed, Web of Science, and Google Scholar were searched systematically for studies reporting comorbidities in FH patients. Finally, 23 studies were included after excluding duplicates, papers with unrelated titles, reviews, abstracts, and papers with not sufficient data. Results showed that among the comorbidities that have been studied; FH patients had a greater prevalence of CKD. In terms of diabetes, the data are inconsistent, with some research indicating a higher prevalence of diabetes in FH patients and mostly indicating the opposite. Polymorphism study showed that hypertension has been linked to FH; however, the prevalence of the hypertensive subjects varies among FH groups. In comparison to the general population, cancer was found to have a lower or similar prevalence in FH patients. More research is needed in this area due to the variability of the results of the relationship between diabetes and FH and the small number of studies on cancer. In conclusion only CKD can be considered as an important and prevalent comorbidity in FH population after CVDs.

Familial Hypercholesterolemia (FH) Registry Worldwide: A Systematic Review

Familial hypercholesterolemia (FH) is the most common genetic disease which accelerates the development of premature coronary artery disease (CAD) in young adults if remains untreated. The overall prevalence of FH is currently unknown and is usually underdiagnosed and undertreated worldwide. FH registry in different geographical area is a mission that helps early diagnosis of FH patients in the general population. PubMed, ISI Web of Science, Scopus, and Google Scholar were searched systematically for studies and reports on the FH registry using related keywords. Finally, 27 studies were included in this review. Most of the studies used the CASCADE screening method based on 1 or more than 1 of the 3 well-established FH criteria namely, the Dutch Lipid Clinic Network, Simon Broome Register, or Make Early Diagnosis to Prevent Early Death criteria. Except for a small number of studies that the genetic and molecular methods were used, in other studies only clinical diagnosis was applied. All these studies claimed that the FH registry causes the identification of many new cases as a result of used CASCADE screening and referral to lipid clinics. They concluded that the FH registry increases general and also physician awareness on FH prevalence and its related complications which in the long-term will improve FH management. This indicates that in other parts of the world, the FH registry should be established as well so that more accurate statistics on the prevalence of this disease can be found worldwide which would help in diagnosis and prevention.

Clinical Features of Familial Hypercholesterolemia in Children and Adults in EAS-FHSC Regional Center for Rare Diseases in Poland

BACKGROUND

Familial hypercholesterolemia (FH) is a genetic autosomal co-dominant metabolic disorder leading to elevated circulating concentrations of low-density lipoprotein cholesterol (LDL-C). Early development of atherosclerotic cardiovascular disease (ASCVD) is common in affected patients. We aimed to evaluate the characteristics and differences in the diagnosis and therapy of FH children and adults. Methods: All consecutive patients who were diagnosed with FH, both phenotypically and with genetic tests, were included in this analysis. All patients are a part of the European Atherosclerosis Society FH-Study Collaboration (FHSC) regional center for rare diseases at the Polish Mother's Memorial Hospital Research Institute (PMMHRI) in Lodz, Poland. Results: Of 103 patients with FH, there were 16 children (15.5%) at mean age of 9 ± 3 years and 87 adults aged 41 ± 16; 59% were female. Children presented higher mean levels of total cholesterol, LDL-C, and high-density lipoprotein cholesterol (HDL-C) measured at the baseline visit (TC 313 vs. 259 mg/dL (8.0 vs. 6.6 mmol/L), p = 0.04; LDL 247 vs. 192 mg/dL (6.3 vs. 4.9 mmol/L), p = 0.02, HDL 53 vs. 48 mg/dL (1.3 vs. 1.2 mmol/L), p = 0.009). Overall, 70% of adult patients and 56% of children were prescribed statins (rosuvastatin or atorvastatin) on admission. Combination therapy (dual or triple) was administered for 24% of adult patients. Furthermore, 13.6% of adult patients and 19% of children reported side effects of statin therapy; most of them complained of muscle pain. Only 50% of adult patients on combination therapy achieved their treatment goals. None of children achieved the treatment goal.

CONCLUSIONS

Despite a younger age of FH diagnosis, children presented with higher mean levels of LDL-C than adults. There are still urgent unmet needs concerning effective lipid-lowering therapy in FH patients, especially the need for greater use of combination therapy, which may allow LDL-C targets to be met in most of the patients.

Heterozygous familial hypercholesterolemia: prevalence and control rates

Introduction: Heterozygous familial hypercholesterolemia (heFH) is associated with a very high risk for cardiovascular events. Treatment with potent statins substantially reduces cardiovascular morbidity in these patients. Moreover, combination therapy with statins plus ezetimibe and/or proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors facilitates achievement of low-density lipoprotein cholesterol (LDL-C) targets in patients with heFH. However, heFH remains underdiagnosed and undertreated worldwide.Areas covered: In this review, we summarize current evidence on the prevalence and control rates of heFH. Accumulating data suggest that heFH is one of the most common hereditary metabolic disorders, affecting approximately 1 in every 300 individuals. However, only a small minority of patients with heFH achieve LDL-C targets, even in high-income countries and in subjects followed-up in specialized lipid clinics.Expert opinion: Given the underdiagnosis of heFH using cascade and opportunistic screening, wider, population-based screening strategies should be evaluated for their feasibility and cost-effectiveness if we aspire to timely diagnosis and therefore prevention of cardiovascular morbidity and mortality in this very high risk population. Overcoming inertia in uptitrating statin dose, adding ezetimibe and/or PCSK9 inhibitors along with more generous reimbursement for lipid-lowering agents in patients with heFH are essential for improving goal attainment rates.

Homozygous Familial Hypercholesterolemia

Familial hypercholesterolemia (FH) is an inherited disorder with retarded clearance of plasma LDL caused by mutations of the genes involved in the LDL receptor-mediated pathway and most of them exhibit autosomal dominant inheritance. Homozygotes of FH (HoFH) may have plasma LDL-C levels, which are at least twice as high as those of heterozygous FH (HeFH) and therefore four times higher than normal levels. Prevalence of HoFH had been estimated as 1 in 1,000,000 before but more recent genetic analysis surveys predict 1 in 170,000 to 300,000. Since LDL receptor activity is severely impaired, HoFH patients do not or very poorly respond to medications to enhance activity, such as statins, and have a poorer prognosis compared to HeFH. HoFH should therefore be clinically distinguished from HeFH. Thorough family studies and genetic analysis are recommended for their accurate diagnosis.

Fatal cardiovascular complications could develop even in the first decade of life for HoFH, so aggressive lipid-lowering therapy should be initiated as early as possible. Direct removal of plasma LDL by lipoprotein apheresis has been the principal measure for these patients. However, this treatment alone may not achieve stable LDL-C target levels and combination with drugs should be considered. The lipid-lowering effects of statins and PCSK9 inhibitors substantially vary depending on the remaining LDL receptor activity of individual patients. On the other hand, the action an MTP inhibitor is independent of LDL receptor activity, and it is effective in most HoFH cases.

This review summarizes the key clinical issues of HoFH as well as insurance coverage available under the Japanese public healthcare system.