Familial hypercholesterolemia in a European Mediterranean population-Prevalence and clinical data from 2.5 million primary care patients

Sex Differences in Diagnosis, Treatment, and Cardiovascular Outcomes in Homozygous Familial Hypercholesterolemia

Importance

Homozygous familial hypercholesterolemia (HoFH) is a rare genetic condition characterized by extremely increased low-density lipoprotein (LDL) cholesterol levels and premature atherosclerotic cardiovascular disease (ASCVD). Heterozygous familial hypercholesterolemia (HeFH) is more common than HoFH, and women with HeFH are diagnosed later and undertreated compared to men; it is unknown whether these sex differences also apply to HoFH.

Objective

To investigate sex differences in age at diagnosis, risk factors, lipid-lowering treatment, and ASCVD morbidity and mortality in patients with HoFH.

Design, Setting, and Participants

Sex-specific analyses for this retrospective cohort study were performed using data from the HoFH International Clinical Collaborators (HICC) registry, the largest global dataset of patients with HoFH, spanning 88 institutions across 38 countries. Patients with HoFH who were alive during or after 2010 were eligible for inclusion. Data entry occurred between February 2016 and December 2020. Data were analyzed from June 2022 to June 2023.

Main Outcomes and Measures

Comparison between women and men with HoFH regarding age at diagnosis, presence of risk factors, lipid-lowering treatment, prevalence, and onset and incidence of ASCVD morbidity (myocardial infarction [MI], aortic stenosis, and combined ASCVD outcomes) and mortality.

Results

Data from 389 women and 362 men with HoFH from 38 countries were included. Women and men had similar age at diagnosis (median [IQR], 13 [6-26] years vs 11 [5-27] years, respectively), untreated LDL cholesterol levels (mean [SD], 579 [203] vs 596 [186] mg/dL, respectively), and cardiovascular risk factor prevalence, except smoking (38 of 266 women [14.3%] vs 59 of 217 men [27.2%], respectively). Prevalence of MI was lower in women (31 of 389 [8.0%]) than men (59 of 362 [16.3%]), but age at first MI was similar (mean [SD], 39 [13] years in women vs 38 [13] years in men). Treated LDL cholesterol levels and lipid-lowering therapy were similar in both sexes, in particular statins (248 of 276 women [89.9%] vs 235 of 258 men [91.1%]) and lipoprotein apheresis (115 of 317 women [36.3%] vs 118 of 304 men [38.8%]). Sixteen years after HoFH diagnosis, women had statistically significant lower cumulative incidence of MI (5.0% in women vs 13.7% in men; subdistribution hazard ratio [SHR], 0.37; 95% CI, 0.21-0.66) and nonsignificantly lower all-cause mortality (3.0% in women vs 4.1% in men; HR, 0.76; 95% CI, 0.40-1.45) and cardiovascular mortality (2.6% in women vs 4.1% in men; SHR, 0.87; 95% CI, 0.44-1.75).

Conclusions and Relevance

In this cohort study of individuals with known HoFH, MI was higher in men compared with women yet age at diagnosis and at first ASCVD event were similar. These findings suggest that early diagnosis and treatment are important in attenuating the excessive cardiovascular risk in both sexes.

Genetic backgrounds and diagnosis of familial hypercholesterolemia

Lipid disorders play a critical role in the intricate development of atherosclerosis and its clinical consequences, such as coronary heart disease and stroke. These disorders are responsible for a significant number of deaths in many adult populations worldwide. Familial hypercholesterolemia (FH) is a genetic disorder that causes extremely high levels of LDL cholesterol. The most common mutations occur in genes responsible for low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), or proprotein convertase subtilisin/kexin type 9 (PCSK9). While genetic testing is a dependable method for diagnosing the disease, it may not detect primary mutations in 20%-40% of FH cases.

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.

Sex Differences in Familial Hypercholesterolemia

PURPOSE OF REVIEW

This review aims to summarize the existing research on sex differences in familial hypercholesterolemia (FH) across the lifespan.

RECENT FINDINGS

From childhood onward, total- and low-density lipoprotein cholesterol (LDL-C) levels in girls are higher than those in boys with FH. By the age of 30 years, women with FH have a higher LDL-C burden than men. In adulthood, women are diagnosed later than men, receive less lipid-lowering treatment, and consequently have higher LDL-C levels. An excessive atherosclerotic cardiovascular disease risk is reported in young female compared to male FH patients. The periods of pregnancy and breastfeeding contribute to treatment loss and increased cholesterol burden. Earlier initiation of treatment, especially in girls with FH, and lifelong treatment during all life stages are important. Future research should aim to recruit both women and men, report sex-specific data, and investigate the impact of the female life course on cardiovascular outcomes. Future guidelines should include sex-specific aspects.

Risk factors for cardiovascular events in patients with heterozygous familial hypercholesterolaemia: protocol for a systematic review

INTRODUCTION

Heterozygous familial hypercholesterolaemia (heFH) is the most common monogenic cause of premature atherosclerotic cardiovascular disease. The precise diagnosis of heFH is established by genetic testing. This systematic review will investigate the risk factors that predict cardiovascular events in patients with a genetic diagnosis of heFH.

METHODS AND ANALYSIS

Our literature search will cover publications from database inception until June 2023. We will undertake a search of CINAHL (trial), clinicalKey, Cochrane Library, DynaMed, Embase, Espacenet, Experiments (trial), Fisterra, ÍnDICEs CSIC, LILACS, LISTA, Medline, Micromedex, NEJM Resident 360, OpenDissertations, PEDro, Trip Database, PubPsych, Scopus, TESEO, UpToDate, Web of Science and the grey literature for eligible studies. We will screen the title, abstract and full-text papers for potential inclusion and assess the risk of bias. We will employ the Cochrane tool for randomised controlled trials and non-randomised clinical studies and the Newcastle-Ottawa Scale for assessing the risk of bias in observational studies. We will include full-text peer-reviewed publications, reports of a cohort/registry, case-control and cross-sectional studies, case report/series and surveys related to adults (≥18 years of age) with a genetic diagnostic heFH. The language of the searched studies will be restricted to English or Spanish. The Grading of Recommendations, Assessment, Development and Evaluation approach will be used to assess the quality of the evidence. Based on the data available, the authors will determine whether the data can be pooled in meta-analyses.

ETHICS AND DISSEMINATION

All data will be extracted from published literature. Hence, ethical approval and patient informed consent are not required. The findings of the systematic review will be submitted for publication in a peer-reviewed journal and presentation at international conferences.

PROSPERO REGISTRATION NUMBER

CRD42022304273.

Clinical Evaluation of Patients with Genetically Confirmed Familial Hypercholesterolemia

Familial hypercholesterolemia (FH) is the most common genetic disorder associated with premature atherosclerotic cardiovascular (CV) disease (ASCVD). However, it still is severely underdiagnosed. Initiating lipid-lowering therapy (LLT) in FH patients early in life can substantially reduce their ASCVD risk. As a result, identifying FH is of the utmost importance. The increasing availability of genetic testing may be useful in this regard. We aimed to evaluate the genetic profiles, clinical characteristics, and gender differences between the first consecutive patients referred for genetic testing with FH clinical suspicion in our institution (a Spanish cohort). Clinical information was reviewed, and all participants were sequenced for the main known genes related to FH: LDLR, APOB, PCSK9 (heterozygous FH), LDLRAP1 (autosomal recessive FH), and two other genes related to hyperlipidaemia (APOE and LIPA). The genetic yield was 32%. Their highest recorded LDLc levels were 294 ± 65 SD mg. However, most patients (79%) were under > 1 LLT medication, and their last mean LDLc levels were 135 ± 51 SD. LDLR c.2389+4A>G was one of the most frequent pathogenic/likely pathogenic variants and its carriers had significantly worse LDLc highest recorded levels (348 ± 61 SD vs. 282 ± 60 SD mg/dL, p = 0.002). Moreover, we identified an homozygous carrier of the pathogenic variant LDLRAP1 c.207delC (autosomal recessive FH). Both clinical and genetic hypercholesterolemia diagnosis was significantly established earlier in men than in women (25 years old ± 15 SD vs. 35 years old ± 19 SD, p = 0.02; and 43 ± 17 SD vs. 54 ± 19 SD, p = 0.02, respectively). Other important CV risk factors were found in 44% of the cohort. The prevalence of family history of premature ASCVD was high, whereas personal history was exceptional. Our finding reaffirms the importance of early detection of FH to initiate primary prevention strategies from a young age. Genetic testing can be very useful. As it enables familial cascade genetic testing, early prevention strategies can be extended to all available relatives at concealed high CV risk.

Women with familial hypercholesterolemia phenotype are undertreated and poorly controlled compared to men

Familial hypercholesterolemia (FH) is an autosomal dominant disease that has a prevalence of approximately 1/250 inhabitants and is the most frequent cause of early coronary heart disease (CHD). We included 1.343.973 women and 1.210.671 men with at least one LDL-c measurement from the Catalan primary care database. We identified 14.699 subjects with Familial hypercholesterolemia-Phenotype (FH-P) based on LDL-c cut-off points by age (7.033 and 919 women, and 5.088 and 1659 men in primary and secondary prevention, respectively). Lipid lower therapy (LLT), medication possession ratio (MPR) as an indicator of adherence, and number of patients that reached their goal on lipid levels were compared by sex. In primary and secondary prevention, 69% and 54% of women (P = 0.001) and 64% and 51% of men (P = 0.001) were on low-to-moderate-potency LLT. Adherence to LLT was reduced in women older than 55 years, especially in secondary prevention (P = 0.03), where the percentage of women and men with LDL-c > 1.81 mmol/L were 99.9% and 98.9%, respectively (P = 0.001). Women with FH-P are less often treated with high-intensity LLT, less adherent to LLT, and have a lower probability of meeting their LDL-c goals than men, especially in secondary prevention.

Prevalence of Diabetes and Its Association with Atherosclerotic Cardiovascular Disease Risk in Patients with Familial Hypercholesterolemia: An Analysis from the Hellenic Familial Hypercholesterolemia Registry (HELLAS-FH)

Familial hypercholesterolemia (FH) and type 2 diabetes mellitus (T2DM) are both associated with a high risk of atherosclerotic cardiovascular disease (ASCVD). Little is known about the prevalence of T2DM and its association with ASCVD risk in FH patients. This was a cross-sectional analysis from the Hellenic Familial Hypercholesterolemia Registry (HELLAS-FH) including adults with FH (n = 1719, mean age 51.3 ± 14.6 years). Of FH patients, 7.2% had a diagnosis of T2DM. The prevalence of ASCVD, coronary artery disease (CAD), and stroke was higher among subjects with T2DM compared with those without (55.3% vs. 23.3%, 48.8% vs. 20.7%, 8.3% vs. 2.7%, respectively, p < 0.001). When adjusted for age, systolic blood pressure, smoking, body mass index, hypertension, waist circumference, triglyceride levels, high-density lipoprotein cholesterol levels, and gender, T2DM was significantly associated with prevalent ASCVD [OR 2.0 (95% CI 1.2−3.3), p = 0.004]. FH patients with T2DM were more likely to have undergone coronary revascularization than those without (14.2% vs. 4.5% for coronary artery bypass graft, and 23.9% vs. 11.5% for percutaneous coronary intervention, p < 0.001). T2DM is associated with an increased risk for prevalent ASCVD in subjects with FH. This may have implications for risk stratification and treatment intensity in these patients.

Implementation of a biochemical, clinical, and genetic screening programme for familial hypercholesterolemia in 26 centres in Spain: The ARIAN study

Background: Familial hypercholesterolemia (FH) is clearly underdiagnosed and undertreated. The aim of this present study is to assess the benefits of FH screening through a joint national program implemented between clinical laboratories and lipid units.

Methods: All clinical laboratory tests from 1 January 2017 to 31 December 2018 were reviewed, and those with LDL cholesterol (LDL-C) levels &gt;250 mg/dl were identified in subjects &gt;18 years of age of both sexes. Once secondary causes had been ruled out, the treating physician was contacted and advised to refer the patient to an LU to perform the Dutch Lipid Clinic Network score and to request genetic testing if the score was ≥6 points. Next Generation Sequencing was used to analyse the promoter and coding DNA sequences of four genes associated with FH (LDLR, APOB, PCSK9, APOE) and two genes that have a clinical overlap with FH characteristics (LDLRAP1 and LIPA). A polygenic risk score based on 12 variants was also obtained.

Results: Of the 3,827,513 patients analyzed in 26 centers, 6,765 had LDL-C levels &gt;250 mg/dl. Having ruled out secondary causes and known cases of FH, 3,015 subjects were included, although only 1,205 treating physicians could be contacted. 635 patients were referred to an LU and genetic testing was requested for 153 of them. This resulted in a finding of sixty-seven pathogenic variants for FH, 66 in the LDLR gene and one in APOB. The polygenic risk score was found higher in those who had no pathogenic variant compared to those with a pathogenic variant.

Conclusion: Despite its limitations, systematic collaboration between clinical laboratories and lipid units allows for the identification of large numbers of patients with a phenotypic or genetic diagnosis of FH, which will reduce their vascular risk. This activity should be part of the clinical routine.

Leveraging Healthcare System Data to Identify High-Risk Dyslipidemia Patients

PURPOSE OF REVIEW

While randomized controlled trials have historically served as the gold standard for shaping guideline recommendations, real-world data are increasingly being used to inform clinical decision-making. We describe ways in which healthcare systems are generating real-world data related to dyslipidemia and how these data are being leveraged to improve patient care.

RECENT FINDINGS

The electronic medical record has emerged as a major source of clinical data, which alongside claims and pharmacy dispending data is enabling healthcare systems the ability to identify care gaps (underdiagnosis and undertreatment) in patients with dyslipidemia. Availability of this data also allows healthcare systems the ability to test and deliver interventions at the point-of-care. Real-world data possess great potential as a complement to randomized controlled trials. Healthcare systems are uniquely positioned to not only define care gaps and areas of opportunity, but to also to leverage tools (e.g., clinical decision support, case identification) aimed at closing them.

Healthcare worker-based opportunistic screening for familial hypercholesterolemia in a low-resource setting

Background & objective

Heterozygous familial hypercholesterolemia (FHeH) is important risk factor for premature coronary artery disease (CAD). Strategies for its diagnosis and prevalence have not been well studied in India. We performed healthcare worker-based opportunistic screening to assess feasibility for determining its prevalence.

Methods

A healthcare worker was trained in use of Dutch Lipid Clinic Network (DLCN) criteria for diagnosis of FHeH. Successive eligible individuals (n = 3000 of 3450 screened) presenting to biochemistry laboratories of two hospitals for blood lipid measurements were evaluated for FHeH. Cascade screening or genetic studies were not performed. Descriptive statistics are reported.

Results

We included 2549 participants (men 1870, women 679) not on statin therapy. Health worker screened 25–30 individuals/day in 6–10 minutes each. The mean age was 46.2±11y. Variables of DLCN criteria were more in women vs men: family history 51.1 vs 35.6%, past CAD 48.2 vs 20.1%, arcus cornealis 1.1 vs 0.3%, tendon xanthoma 0.3 vs 0.1%, and LDL cholesterol 190–249 mg/dl in 8.5 vs 2.4%, 250–329 mg/dl in 0.7 vs 0% and ≥330 mg/dl in 0.3 vs 0% (p<0.01). Definite FHeH (DLCN score >8) was in 15 (0.59%, frequency 1:170) and probable FHeH (score 6–8) in 87 (3.4%, frequency 1:29). The prevalence was significantly greater in women, age <50y and in those with hypertension, diabetes and known CAD.

Conclusions

Healthcare worker-led opportunistic screening for diagnosis of FHeH using DLCN criteria is feasible in low-resource settings. The results show significant prevalence of clinically detected definite and probable FHeH in the population studied.

Clinical decision support for familial hypercholesterolemia (CDS-FH): Rationale and design of a cluster randomized trial in primary care

BACKGROUND

Familial hypercholesterolemia (FH) is an underdiagnosed and undertreated genetic disorder with high risk of premature atherosclerotic cardiovascular disease and death. Clinical decision support (CDS) systems have the potential to aid in the identification and management of patients with FH. Prior studies using computer-based systems to screen patients for FH have shown promising results, but there has been no randomized controlled trial conducted. The aim of the current cluster randomized study is to evaluate if a CDS can increase the identification of FH.

METHODS

We have developed a CDS integrated in the electronic health records that will be activated in patients with elevated cholesterol levels (total cholesterol >8 mmol/L or low-density lipoprotein-cholesterol >5.5 mmol/L, adjusted for age, ongoing lipid lowering therapy and presence of premature coronary artery disease) at increased risk for FH. When activated, the CDS will urge the physician to send an automatically generated referral to the local lipid clinic for further evaluation. To evaluate the effects of the CDS, all primary care clinics will be cluster randomized 1:1 to either CDS intervention or standard care in a Swedish region with almost 500,000 inhabitants. The primary endpoint will be the number of patients diagnosed with FH at 30 months. Resource use and long-term health consequences will be estimated to assess the cost-effectiveness of the intervention.

CONCLUSION

Despite increasing awareness of FH, the condition remains underdiagnosed and undertreated. The present study will investigate whether a CDS can increase the number of patients being diagnosed with FH.

Twelve Variants Polygenic Score for Low-Density Lipoprotein Cholesterol Distribution in a Large Cohort of Patients With Clinically Diagnosed Familial Hypercholesterolemia With or Without Causative Mutations

Background

A significant proportion of individuals clinically diagnosed with familial hypercholesterolemia (FH), but without any disease‐causing mutation, are likely to have polygenic hypercholesterolemia. We evaluated the distribution of a polygenic risk score, consisting of 12 low‐density lipoprotein cholesterol (LDL‐C)‐raising variants (polygenic LDL‐C risk score), in subjects with a clinical diagnosis of FH.

Methods and Results

Within the Lipid Transport Disorders Italian Genetic Network (LIPIGEN) study, 875 patients who were FH‐mutation positive (women, 54.75%; mean age, 42.47±15.00 years) and 644 patients who were FH‐mutation negative (women, 54.21%; mean age, 49.73±13.54 years) were evaluated. Patients who were FH‐mutation negative had lower mean levels of pretreatment LDL‐C than patients who were FH‐mutation positive (217.14±55.49 versus 270.52±68.59 mg/dL, P<0.0001). The mean value (±SD) of the polygenic LDL‐C risk score was 1.00 (±0.18) in patients who were FH‐mutation negative and 0.94 (±0.20) in patients who were FH‐mutation positive (P<0.0001). In the receiver operating characteristic analysis, the area under the curve for recognizing subjects characterized by polygenic hypercholesterolemia was 0.59 (95% CI, 0.56–0.62), with sensitivity and specificity being 78% and 36%, respectively, at 0.905 as a cutoff value. Higher mean polygenic LDL‐C risk score levels were observed among patients who were FH‐mutation negative having pretreatment LDL‐C levels in the range of 150 to 350 mg/dL (150–249 mg/dL: 1.01 versus 0.91, P<0.0001; 250–349 mg/dL: 1.02 versus 0.95, P=0.0001). A positive correlation between polygenic LDL‐C risk score and pretreatment LDL‐C levels was observed among patients with FH independently of the presence of causative mutations.

Conclusions

This analysis confirms the role of polymorphisms in modulating LDL‐C levels, even in patients with genetically confirmed FH. More data are needed to support the use of the polygenic score in routine clinical practice.

Genetic Determinants of Plasma Low-Density Lipoprotein Cholesterol Levels: Monogenicity, Polygenicity, and "Missing" Heritability

Changes in plasma low-density lipoprotein cholesterol (LDL-c) levels relate to a high risk of developing some common and complex diseases. LDL-c, as a quantitative trait, is multifactorial and depends on both genetic and environmental factors. In the pregenomic age, targeted genes were used to detect genetic factors in both hyper- and hypolipidemias, but this approach only explained extreme cases in the population distribution. Subsequently, the genetic basis of the less severe and most common dyslipidemias remained unknown. In the genomic age, performing whole-exome sequencing in families with extreme plasma LDL-c values identified some new candidate genes, but it is unlikely that such genes can explain the majority of inexplicable cases. Genome-wide association studies (GWASs) have identified several single-nucleotide variants (SNVs) associated with plasma LDL-c, introducing the idea of a polygenic origin. Polygenic risk scores (PRSs), including LDL-c-raising alleles, were developed to measure the contribution of the accumulation of small-effect variants to plasma LDL-c. This paper discusses other possibilities for unexplained dyslipidemias associated with LDL-c, such as mosaicism, maternal effect, and induced epigenetic changes. Future studies should consider gene-gene and gene-environment interactions and the development of integrated information about disease-driving networks, including phenotypes, genotypes, transcription, proteins, metabolites, and epigenetics.

Prevalence of familial hypercholesterolemia phenotype and ten-year risk of cardiovascular events in a working population in primary prevention: The ICARIA study

BACKGROUND AND AIMS

We aimed to assess the prevalence of familial hypercholesterolaemia (FH) and to determine the incidence of cardiovascular events during a 10-year follow up in individuals with FH, compared to unaffected individuals in a working, middle-aged/young population.

METHODS AND RESULTS

576,724 active workers (36 ± 10 years-old, 70% men) without cardiovascular disease were given regular health check-ups and followed for a median of 8.5 years (i.e., 4,123,927 person-years). The FH phenotype was defined according to validated low-density lipoprotein-cholesterol thresholds, adjusted for age and sex. The primary outcome was a first cardiovascular event, whether fatal or non-fatal. We found that 707 workers (0.12% or 1 in 816 individuals) met the criteria for a heterozygous FH phenotype. During the follow-up, cardiovascular events occurred in 23 of 707 (3.25%) subjects with the FH phenotype and in 3297 of 576,017 (0.57%) subjects without the FH phenotype (p<0.001). The hazard ratio (HR, assessed with a Cox regression model) for the primary outcome was 5.7 (99% CI 3.33-9.78), before adjustments, and 4.7 (99% CI 2.62-8.58) after adjusting for sex, age, smoking, blood pressure, and diabetes. The HRs were significant for both men and women, but the magnitude of the effect was greater for men than for women.

CONCLUSIONS

Our findings confirmed the high incidence of cardiovascular disease in individuals with untreated FH. We showed that regular health check-ups in an active, and mostly young, working population could contribute to the early identification of FH. Therefore, this approach may provide an opportunity for early treatment.

Risk Assessment and Clinical Management of Children and Adolescents with Heterozygous Familial Hypercholesterolaemia. A Position Paper of the Associations of Preventive Pediatrics of Serbia, Mighty Medic and International Lipid Expert Panel

Heterozygous familial hypercholesterolaemia (FH) is among the most common genetic metabolic lipid disorders characterised by elevated low-density lipoprotein cholesterol (LDL-C) levels from birth and a significantly higher risk of developing premature atherosclerotic cardiovascular disease. The majority of the current pediatric guidelines for clinical management of children and adolescents with FH does not consider the impact of genetic variations as well as characteristics of vascular phenotype as assessed by recently developed non-invasive imaging techniques. We propose a combined integrated approach of cardiovascular (CV) risk assessment and clinical management of children with FH incorporating current risk assessment profile (LDL-C levels, traditional CV risk factors and familial history) with genetic and non-invasive vascular phenotyping. Based on the existing data on vascular phenotype status, this panel recommends that all children with FH and cIMT ≥0.5 mm should receive lipid lowering therapy irrespective of the presence of CV risk factors, family history and/or LDL-C levels Those children with FH and cIMT ≥0.4 mm should be carefully monitored to initiate lipid lowering management in the most suitable time. Likewise, all genetically confirmed children with FH and LDL-C levels ≥4.1 mmol/L (160 mg/dL), should be treated with lifestyle changes and LLT irrespective of the cIMT, presence of additional RF or family history of CHD.

Strategies for screening for familial hypercholesterolaemia in primary care and other community settings

BACKGROUND

Familial hypercholesterolaemia is a common inherited condition that is associated with premature cardiovascular disease. The increased cardiovascular morbidity and mortality, resulting from high levels of cholesterol since birth, can be prevented by starting lipid-lowering therapy. However, the majority of patients in the UK and worldwide remain undiagnosed. Established diagnostic criteria in current clinical practice are the Simon-Broome and Dutch Lipid Clinical network criteria and patients are classified as having probable, possible or definite familial hypercholesterolaemia.

OBJECTIVES

To assess the effectiveness of healthcare interventions strategies to systematically improve identification of familial hypercholesterolaemia in primary care and other community settings compared to usual care (incidental approaches to identify familial hypercholesterolaemia in primary care and other community settings).

SEARCH METHODS

We searched the Cochrane Inborn Errors of Metabolism Trials Register. Date of last search: 13 September 2021. We also searched databases (Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, PubMed, Embase, CINAHL, Web of Science, and SCOPUS) as well as handsearching relevant conference proceedings, reference lists of included articles, and the grey literature. Date of last searches: 05 March 2020.  SELECTION CRITERIA: As per the Effective Practice and Organisation of Care (EPOC) Group guidelines, we planned to include randomised controlled trials (RCTs), cluster-RCTs and non-randomised studies of interventions (NRSI). Eligible NRSI were non-randomised controlled trials, prospective cohort studies, controlled before-and-after studies, and interrupted-time-series studies. We planned to selected studies with healthcare interventions strategies that aimed to systematically identify people with possible or definite clinical familial hypercholesterolaemia, in primary care and other community settings. These strategies would be compared with usual care or no intervention. We considered participants of any age from the general population who access primary care and other community settings.

DATA COLLECTION AND ANALYSIS

Two authors planned to independently select studies according to the inclusion criteria, to extract data and assess for risk of bias and the certainty of the evidence (according to the GRADE criteria). We contacted corresponding study authors in order to obtain further information for all the studies considered in the review.

MAIN RESULTS

No eligible RCTs or NRSIs were identified for inclusion, however, we excluded 28 studies.

AUTHORS' CONCLUSIONS

Currently, there are no RCTs or controlled NRSI evidence to determine the most appropriate healthcare strategy to systematically identify possible or definite clinical familial hypercholesterolaemia in primary care or other community settings. Uncontrolled before-and-after studies were identified, but were not eligible for inclusion. Further studies assessing healthcare strategies of systematic identification of familial hypercholesterolaemia need to be conducted with diagnosis confirmed by genetic testing or validated through clinical phenotype (or both).

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.

Implantation of a biochemical and genetic screening programme for family hypercholesterolaemia. Collaboration between the clinical laboratory and lipid units: Design of the ARIAN Project

INTRODUCTION AND OBJECTIVE

Familial hypercholesterolaemia (FH) is the most common genetic disorder associated with premature coronary artery disease due to the presence of LDL-C cholesterol increased from birth. It is underdiagnosed and undertreated. The primary objective of the ARIAN project was to determine the number of patients diagnosed with FH after implementing a new screening procedure from the laboratory.

MATERIAL AND METHODS

This project was designed as a retrospective analysis by consulting the computer system. We selected from databases serum samples from patients ≥ 18 years with direct or calculated LDL-C>250mg/dL from 1 January 2017 to 31 December 2018. Once secondary causes had been ruled out, the requesting primary care physician was notified that their patient might have FH and to arrange a priority appointment in the lipid unit. All patients with a score of ≥ 6 points according to the Dutch Lipid Clinic Criteria were proposed for a genetic study RESULTS: By December 30th, 2020, 24 centres out of the initial 55 had submitted results. The number of patients analysed up to that point was 3,266,341, which represents 34% of the population served in those health areas (9,727,434).

CONCLUSIONS

The identification of new subjects with FH through this new strategy from the laboratory and their referral to lipid units should increase the number of patients treated in lipid units and initiate familial cascade screening.

LDL cholesterol and atherosclerosis: The evidence

The lipid theory of atherosclerosis dates back more than a century. Despite this, some authors have questioned the relevance of hypercholesterolaemia in its development. Multiple experimental, epidemiological, and clinical evidence underpins this association. Atherosclerotic cardiovascular disease remains as the major cause of mortality in the world. Recent genetic studies of Mendelian randomisation and randomised clinical trials aimed at LDL cholesterol reduction, are summarised in this article. They, unequivocally ratify the aetiological role of LDL cholesterol in the development of atherosclerosis. Thus, LDL cholesterol lowering is the cornerstone of lipid lowering therapy for the reduction of cardiovascular complications of atherosclerosis.

Systematic Identification of Familial Hypercholesterolaemia in Primary Care-A Systematic Review

Familial hypercholesterolaemia (FH) is a common inherited cause of premature cardiovascular disease, but the majority of patients remain undiagnosed. The aim of this systematic review was to assess the effectiveness of interventions to systematically identify FH in primary care. No randomised, controlled studies were identified; however, three non-randomised intervention studies were eligible for inclusion. All three studies systematically identified FH using reminders (on-screen prompts) in electronic health records. There was insufficient evidence that providing comments on laboratory test results increased the identification of FH using the Dutch Lipid Clinic Network (DLCN) criteria. Similarly, using prompts combined with postal invitation demonstrated no significant increase in definite FH identification using Simon-Broome (SB) criteria; however, the identification of possible FH increased by 25.4% (CI 17.75 to 33.97%). Using on-screen prompts alone demonstrated a small increase of 0.05% (95% CI 0.03 to 0.07%) in identifying definite FH using SB criteria; however, when the intervention was combined with an outreach FH nurse assessment, the result was no significant increase in FH identification using a combination of SB and DLCN criteria. None of the included studies reported adverse effects associated with the interventions. Currently, there is insufficient evidence to determine which is the most effective method of systematically identifying FH in non-specialist settings.

Dietary intake and lipid levels in Norwegian and Spanish children with familial hypercholesterolemia

BACKGROUND AND AIMS

Both the Nordic and Mediterranean diets claim to have a beneficial effect on lipid metabolism and cardiovascular prevention. The objective of this study was to compare diets consumed by children with FH at the time of diagnosis in Norway and Spain and to study their relationship with the lipid profile.

METHODS AND RESULTS

In this cross-sectional study, we appraised the dietary intake in children (4-18 years old) with (n = 114) and without FH (n = 145) from Norway and Spain. We compared Nordic and Mediterranean diet composition differences and determined the association between food groups and lipid profiles.

RESULTS

The Spanish FH group had a higher intake of total fats (mainly monounsaturated fatty acids (MUFAs)), cholesterol and fibre, but a lower intake of polyunsaturated fatty acids (PUFAs) compared to the Norwegian FH group. The Norwegian children consumed more rapeseed oil, low-fat margarine and whole grains and less olive oil, eggs, fatty fish, meat, legumes and nuts. In the Norwegian FH group, fat and MUFAs were directly correlated with total cholesterol, low-density lipoprotein cholesterol and apolipoprotein B and inversely correlated with high-density lipoprotein (HDL-C). In Spanish children with FH, the intake of fats (mainly MUFAs) was directly associated with HDL-C and apolipoprotein A1.

CONCLUSIONS

Despite a similar lipid phenotype, diets consumed by children with FH in Norway and Spain have significant differences at time of diagnosis. Nutrition advice should be more adapted to local intake patterns than on specific nutrient composition.

Massive data screening is a second opportunity to improve the management of patients with familial hypercholesterolemia phenotype

INTRODUCTION

Familial Hypercholesterolemia (FH) is an autosomal dominant disease with an estimated prevalence between 1/200-250. It is under-treated and underdiagnosed. Massive data screening can increase the detection of patients with FH.

METHODS

Study population: Residents in the health coverage area (N: 195.000 inhabitants) and with at least one determination of cholesterol linked to low-density lipoproteins (LDL-C) carried out between January 1, 2010 and December 30, 2019. The highest LDL-C values were selected.

EXCLUSION CRITERIA

nephrotic syndrome, hypothyroidism, Hypothyroid treatment or triglycerides> 400 mg / dL. Seven algorithms suggestive of Familial Hypercholesterolemia Phenotype (HF-P) were analyzed, selecting the most efficient algorithm that could easily be translated into clinical practice.

RESULTS

Based on 6.264.877 assistances and 288.475 patients, after applying the inclusion-exclusion criteria, 504.316 tests were included, corresponding to 106.382 adults and 10.509 <18 years. The selected algorithm presented a prevalence of 0.62%. 840 patients with HF-P were detected, 55.8% being women and 178 <18 years old, 9.3% had a history of cardiovascular disease (CVD) and 16.4% had died. 65% of the patients in primary prevention had LDL-C values> 130 mg / dL and 83% in secondary prevention values> 70mg / dL. A ratio of 7.64 (1-18) patients with HF-P per analytical requesting physician was obtained.

CONCLUSIONS

Massive data screening and patient profiling are effective tools and easily applicable in clinical practice for the detection of patients with FH.

Closing the gap: Identification and management of familial hypercholesterolemia in an integrated healthcare delivery system

BACKGROUND

Familial hypercholesterolemia (FH) is an autosomal dominant genetic disorder that causes markedly elevated risk for early onset coronary artery disease. Despite availability of effective therapy, only 5-10% of affected individuals worldwide are diagnosed.

OBJECTIVE

To develop and evaluate a novel approach for identifying and managing patients with FH in a large integrated health system with a diverse patient population, using inexpensive methods.

METHODS

Using Make Early Diagnosis/Prevent Early Death (MEDPED) criteria, we created a method for identifying patients at high risk for FH within the Kaiser Permanente Northern California electronic medical record. This led to a pragmatic workflow for contacting patients, establishing a diagnosis in a dedicated FH clinic, and initiating management. We prospectively collected data on the first 100 patients to assess implementation effectiveness.

RESULTS

Ninety-three (93.0%, 95%CI: 86.1%-97.1%) of the first 100 evaluated patients were diagnosed with FH (median age = 38 years) of whom only 5% were previously recognized; 48% were taking no lipid-lowering therapy, and 7% had acute coronary symptoms. 82 underwent successful genetic testing of whom 55 (67.1%; 95%CI: 55.8%-77.1%) had a pathogenic mutation. Following clinic evaluation, 83 of 85 (97.6%) medication-eligible patients were prescribed combination lipid-lowering therapy. 20 family members in the healthcare system were diagnosed with FH through cascade testing.

CONCLUSIONS

This novel approach was effective for identifying and managing patients with undiagnosed FH. Care gaps in providing appropriate lipid-lowering therapy were successfully addressed. Further development and dissemination of integrated approaches to FH care are warranted.

Sex differences in cardiovascular morbidity associated with familial hypercholesterolaemia: A retrospective cohort study of the UK Simon Broome register linked to national hospital records

Background and aims

The UK Simon Broome (SB) familial hypercholesterolaemia (FH) register previously reported 3-fold higher standardised mortality ratio for cardiovascular disease (CVD) in women compared to men from 2009 to 2015. Here we examined sex differences in CVD morbidity in FH by national linkage of the SB register with Hospital Episode Statistics (HES).

Methods

Of 3553 FH individuals in the SB register (aged 20–79 years at registration), 2988 (52.5% women) had linked HES records. Standardised Morbidity Ratios (SMbR) compared to an age and sex-matched UK general practice population were calculated [95% confidence intervals] for first CVD hospitalisation in HES (a composite of coronary heart disease (CHD), myocardial infarction (MI), stable or unstable angina, stroke, TIA, peripheral vascular disease (PVD), heart failure, coronary revascularisation interventions).

Results

At registration, men had significantly (p < 0.001) higher prevalence of previous CHD (24.8% vs 17.6%), previous MI (13.2% vs 6.3%), and were commenced on lipid-lowering treatment at a younger age than women (37.5 years vs 42.3 years). The SMbR for composite CVD was 6.83 (6.33–7.37) in men and 7.55 (6.99–8.15) in women. In individuals aged 30–50 years, SMbR in women was 50% higher than in men (15.04 [12.98–17.42] vs 10.03 [9.01–11.17]). In individuals >50 years, SMbR was 33% higher in women than men (6.11 [5.57–6.70] vs 4.59 [4.08–5.15]).

Conclusions

Excess CVD morbidity due to FH remains markedly elevated in women at all ages, but especially those aged 30–50 years. This highlights the need for earlier diagnosis and optimisation of lipid-lowering risk factor management for all FH patients, with particular attention to young women with FH.

•

Males with familial hypercholesterolaemia (FH) had more cardiovascular disease (CVD) risk factors and were commenced on lipid-lowering therapy at a younger age, than females with FH.

•

Individuals with FH had excess rates of hospitalisations for CVD, compared to the general population of non-FH individuals.

•

Excess CVD morbidity due to FH was higher in women than men aged 30 years and over, but especially in those aged 30–50 years.

Polygenic Markers in Patients Diagnosed of Autosomal Dominant Hypercholesterolemia in Catalonia: Distribution of Weighted LDL-c-Raising SNP Scores and Refinement of Variant Selection

Familial hypercholesterolemia (FH) is associated with mutations in the low-density lipoprotein (LDL) receptor (LDLR), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin 9 (PCSK9) genes. A pathological variant has not been identified in 30-70% of clinically diagnosed FH patients, and a burden of LDL cholesterol (LDL-c)-raising alleles has been hypothesized as a potential cause of hypercholesterolemia in these patients. Our aim was to study the distribution of weighted LDL-c-raising single-nucleotide polymorphism (SNP) scores (weighted gene scores or wGS) in a population recruited in a clinical setting in Catalonia. The study included 670 consecutive patients with a clinical diagnosis of FH and a prior genetic study involving 250 mutation-positive (FH/M+) and 420 mutation-negative (FH/M-) patients. Three wGSs based on LDL-c-raising variants were calculated to evaluate their distribution among FH patients and compared with 503 European samples from the 1000 Genomes Project. The FH/M- patients had significantly higher wGSs than the FH/M+ and control populations, with sensitivities ranging from 42% to 47%. A wGS based only on the SNPs significantly associated with FH (wGS8) showed a higher area under the receiver operating characteristic curve, and higher diagnostic specificity and sensitivity, with 46.4% of the subjects in the top quartile. wGS8 would allow for the assignment of a genetic cause to 66.4% of the patients if those with polygenic FH are added to the 37.3% of patients with monogenic FH. Our data indicate that a score based on 8 SNPs and the75th percentile cutoff point may identify patients with polygenic FH in Catalonia, although with limited diagnostic sensitivity and specificity.

Management of Familial Hypercholesterolemia: Current Status and Future Perspectives

Familial hypercholesterolemia (FH) is the most common monogenic disorder associated with premature atherosclerotic cardiovascular disease. Early diagnosis and effective treatment can significantly improve prognosis. Recent advances in the field of lipid metabolism have shed light on the molecular defects in FH and new therapeutic options have emerged. A search of PubMed database up to March 2020 was performed for this review using the following keywords: “familial hypercholesterolemia,” “diagnosis,” “management,” “guideline,” “consensus,” “genetics,” “screening,” “lipid lowering agents.” The prevalence rate of heterozygous FH is approximately 1 in 200 to 250 and FH is underdiagnosed and undertreated in many parts of the world. Diagnostic criteria have been developed to aid the clinical diagnosis of FH. Genetic testing is now available but not widely used. Cascade screening is recommended to identify affected family members, and the benefits of early interventions are clear. Treatment strategy and target is currently based on low-density lipoprotein (LDL) cholesterol levels as the prognosis of FH largely depends on the magnitude of LDL cholesterol-lowering that can be achieved by lipid-lowering therapies. Statins with or without ezetimibe are the mainstay of treatment and are cost-effective. Addition of newer medications like PCSK9 inhibitors is able to further lower LDL cholesterol levels substantially, but the cost is high. Lipoprotein apheresis is indicated in homozygous FH or severe heterozygous FH patients with inadequate response to cholesterol-lowering therapies. In conclusion, FH is a common, treatable genetic disorder, and although our understanding of this disease has improved, many challenges still remain for its optimal management.

Prevalence of Familial Hypercholesterolemia Among the General Population and Patients With Atherosclerotic Cardiovascular Disease

Background:

Contemporary studies suggest that familial hypercholesterolemia (FH) is more frequent than previously reported and increasingly recognized as affecting individuals of all ethnicities and across many regions of the world. Precise estimation of its global prevalence and prevalence across World Health Organization regions is needed to inform policies aiming at early detection and atherosclerotic cardiovascular disease (ASCVD) prevention. The present study aims to provide a comprehensive assessment and more reliable estimation of the prevalence of FH than hitherto possible in the general population (GP) and among patients with ASCVD.

Methods:

We performed a systematic review and meta-analysis including studies reporting on the prevalence of heterozygous FH in the GP or among those with ASCVD. Studies reporting gene founder effects and focused on homozygous FH were excluded. The search was conducted through Medline, Embase, Cochrane, and Global Health, without time or language restrictions. A random-effects model was applied to estimate the overall pooled prevalence of FH in the general and ASCVD populations separately and by World Health Organization regions.

Results:

From 3225 articles, 42 studies from the GP and 20 from populations with ASCVD were eligible, reporting on 7 297 363 individuals/24 636 cases of FH and 48 158 patients/2827 cases of FH, respectively. More than 60% of the studies were from Europe. Use of the Dutch Lipid Clinic Network criteria was the commonest diagnostic method. Within the GP, the overall pooled prevalence of FH was 1:311 (95% CI, 1:250–1:397; similar between children [1:364] and adults [1:303], P =0.60; across World Health Organization regions where data were available, P =0.29; and between population-based and electronic health records–based studies, P =0.82). Studies with ≤10 000 participants reported a higher prevalence (1:200–289) compared with larger cohorts (1:365–407; P <0.001). The pooled prevalence among those with ASCVD was 18-fold higher than in the GP (1:17 [95% CI, 1:12–1:24]), driven mainly by coronary artery disease (1:16; [95% CI, 1:12–1:23]). Between-study heterogeneity was large ( I 2 >95%). Tests assessing bias were nonsignificant ( P >0.3).

Conclusions:

With an overall prevalence of 1:311, FH is among the commonest genetic disorders in the GP, similarly present across different regions of the world, and is more frequent among those with ASCVD. The present results support the advocacy for the institution of public health policies, including screening programs, to identify FH early and to prevent its global burden.

Efficacy of therapeutic lifestyle changes on lipid profiles assessed by NMR in children with familial and non-familial hypercholesterolemia

BACKGROUND AND AIMS

The first line of therapy in children with hypercholesterolaemia is therapeutic lifestyle changes (TLSC). The efficacy of lifestyle intervention in children with familial hypercholesterolaemia (FH), where LDL-C levels are genetically driven, deserves a focused study.

AIMS

To evaluate the impact of a lifestyle education program, focused on food patterns and physical activity, on lipid profiles assessed by nuclear magnetic resonance (NMR) in children with FH vs. non-FH.

METHODS

Phase 1 was a cross-sectional study of baseline characteristics, and phase 2 was a prospective TLSC intervention study. In total, the study included 238 children (4 to 18 years old; 47% girls) attending the lipid unit of our hospital due to high cholesterol levels. Eighty-five were diagnosed with FH (72% genetic positive), and 153 were diagnosed with non-Familial hypercholesterolaemia. A quantitative food frequency questionnaire (FFQ) including 137 items was used. Physical activity (PA) was assessed by the Minnesota questionnaire. The lipid profile was assessed using the 2D-1H-NMR (Liposcale test). A total of 127 children (81 in the FH group) participated in the prospective phase and were re-assessed after 1 year of the TLSC intervention, consisting of education on lifestyle changes delivered by a specialized nutritionist.

RESULTS

The FH and non-FH groups were similar in anthropometry and clinical data, except that those in the FH were slightly younger than those in the non-FH group. Both the FH and non-FH groups showed a similar diet composition characterized by a high absolute calorie intake and a high percentage of fat, mainly saturated fat. The PA was below the recommended level in both groups. After one year of TLSC, the percentage of total and saturated fats was reduced, and the amount of fiber increased significantly in both groups. The percentage of protein increased slightly. The number of children engaged in at least 1 hour/day of PA increased by 56% in the FH group and by 53% in the non-FH group, and both these increases were significant. The total and small-LDL particle numbers were reduced in both groups, although the absolute change was greater in the FH group than in the non-FH group.

CONCLUSIONS

Educational strategies to implement TLSC in children lead to empowerment, increased adherence, and overall metabolic improvement in children with high blood cholesterol, including those with FH.

Derivation and validation of SIDIAP-FHP score: A new risk model predicting cardiovascular disease in familial hypercholesterolemia phenotype

BACKGROUND AND AIMS

Assessment of individual cardiovascular risk, distinguishing primary and secondary prevention, would improve the clinical management of the population with familial hypercholesterolemia. We aimed to develop and validate two risk functions to predict incident and recurrent atherosclerotic cardiovascular disease (ASCVD) in a primary care-based population with familial hypercholesterolemia phenotype (FHP), and to compare their predictive capacity with that of the SpAnish Familial hypErcHolEsterolemiA cohoRT (SAFEHEART) risk equation (SAFEHEART-RE).

METHODS

Data from the Catalan primary care system database (SIDIAP) of patients ≥18 years old with FHP in 2006-2013 were used to develop and validate two risk functions to predict incident and recurrent ASCVD. A validation dataset was also used to compare the model predictive capacity to that of SAFEHEART-RE.

RESULTS

The new model (SIDIAP-FHP) included age, diabetes, smoking, sex (male), hypertension, and baseline low-density lipoprotein cholesterol in the primary prevention cohort and age, diabetes, smoking, and disease characteristics (progressive, recent, polyvascular, or included myocardial infarction) in the secondary prevention cohort. The models demonstrated a fair fit: C-Statistic: 0.71 (95%CI:0.68-0.75) in primary prevention and 0.65 (95%CI:0.60-0.70) in secondary prevention (higher than that of SAFEHEART-RE: 0.64 [95%CI:0.60-0.68] and 0.55 [95%CI:0.51-0.59], respectively; both p < 0.01). The Brier scores obtained with the SIDIAP-FHP score were significantly lower than that obtained with SAFEHEART-RE in both the primary and secondary prevention cohorts.

CONCLUSIONS

The SIDIAP-FHP score provides accurate ASCVD risk estimates for primary and secondary prevention in the FHP population, with better predictive capacity than that of SAFEHEART-RE in this general population, especially in persons with previous ASCVD.

Incidence of Cardiovascular Disease in Patients with Familial Hypercholesterolemia Phenotype: Analysis of 5 Years Follow-Up of Real-World Data from More than 1.5 Million Patients

In the statin era, the incidence of atherosclerotic cardiovascular diseases (ASCVD) in patients with familial hypercholesterolemia (FH) has not been updated. We aimed to determine the incidence of ASCVD in patients with FH-phenotype (FH-P) and to compare it with that of normal low-density lipoprotein cholesterol (LDL-C) patients. We performed a retrospective cohort study using the Database of the Catalan primary care system, including ≥18-year-old patients with an LDL-C measurement. From 1,589,264 patients available before 2009, 12,823 fulfilled FH-P criteria and 514,176 patients were normolipidemic (LDL-C < 115 mg/dL). In primary prevention, patients with FH-P had incidences of ASCVD and coronary heart disease (CHD) of 14.9/1000 and 5.8/1000 person-years, respectively, compared to 7.1/1000 and 2.1/1000 person-years in the normolipidemic group. FH-P showed hazard ratio (HR) of 7.1 and 16.7 for ASCVD and CHD, respectively, in patients younger than 35 years. In secondary prevention, patients with FH-P had incidences of ASCVD and CHD of 89.7/1000 and 34.5/1000 person-years, respectively, compared to 90.9/1000 and 28.2/1000 person-years in the normolipidemic group (HR in patients younger than 35 years: 2.4 and 6.0). In the statin era, FH-P remains associated with high cardiovascular risk, compared with the normolipidemic population. This excess of risk is markedly high in young individuals.

Indications of PCSK9 inhibitors in clinical practice. Recommendations of the Spanish Sociey of Arteriosclerosis (SEA), 2019

A group of experts convened by the Spanish Society of Arteriosclerosis (SEA) has been in charge of updating the SEA document on the indications of PCSK9 inhibitors (PCSK9i) in clinical practice that was published in 2016. This update is justified by the fact that the data from clinical trials carried out on a large scale with PCSK9i have shown that in addition to their high potency to lower atherogenic cholesterol, they reduce the risk of atherosclerotic cardiovascular disease, both in patients with stable disease, and with recent disease, and with a high degree of security. This update provides the recommendations and level of evidence for the prescription of iPCSK9 in patients with homozygous and heterozygous familial hypercholesterolemia, with atherosclerotic cardiovascular disease, and in primary prevention in patients with very high cardiovascular risk. These recommendations have been established taking into account the concentration of LDL-C, the clinical situation of the patient, the additional risk factors and the cost-effectiveness of their use.

Risk of cardiovascular disease outcomes in primary care subjects with familial hypercholesterolaemia: A cohort study

BACKGROUND AND AIMS

Familial hypercholesterolaemia (FH) is a known major cause of premature heart disease. However, the risks of atherosclerotic disease in other vascular regions are less known. We determined the risk of major cardiovascular disease (CVD) outcomes associated with clinical FH.

METHODS

In a retrospective cohort study (1 January, 1999 to 22 July, 2016), we randomly-matched 14,097 UK subjects with clinical FH diagnoses or characteristics (Simon-Broome definite or Dutch Lipid Clinic Score >8) to 42,506 subjects without FH by age, sex, general practice. We excluded those with CVD at baseline. Incident rates for coronary heart disease (CHD), stroke or transient ischaemic attack (TIA) and peripheral vascular disease (PVD) were estimated. Cox proportional hazards regression, stratified on matched-pairs, determined adjusted hazards ratios (HR) for incident CVD.

RESULTS

During follow-up (median 13.8 years), incidence rates (95% CI) of CVD (per 1000 person-years) were 25.6 (24.8-26.3) in FH and 2.9 (2.8-3.1) in non-FH subjects. The risk of CHD, stroke/TIA and PVD was higher in FH compared to non-FH subjects: CHD (HR 10.63, 95% CI 9.82-11.49), stroke/TIA (HR 6.74, 95% CI 5.84-7.77), PVD (HR 7.17, 95% CI 6.08-8.46). The risk of CVD was greater in those with FH characteristics (HR 13.52, 95% CI 12.48-14.65) than those with clinical diagnoses (HR 1.66, 95% CI 1.42-1.93).

CONCLUSIONS

In addition to the recognised increased risk of CHD, subjects with FH have greatly elevated risk of stroke/TIA and PVD. This emphasises need for early diagnosis and preventive interventions beyond CHD, to reduce CVD risk in these individuals.

Prevalence and Treatment of Familial Hypercholesterolemia in France

BACKGROUND

Familial hypercholesterolemia (FH) is known to be underdiagnosed and undertreated. The prevalence of heterozygous FH is estimated to be 1 in 500. Nevertheless, a recent meta-analysis of screening in the general population seems to show that the prevalence of FH is more likely to be 1 in 250.

METHODS

Analysis was based on the third French MONICA and MONALISA population surveys. Participants were randomly recruited in 1995 and 2005 from the general population of 3 regions of France. FH was diagnosed using a modified version of the Dutch Lipid Clinic Network (DLCN) without genetic testing.

RESULTS

The DLCN score was assessed in 7928 participants aged 35 to 74 years; 50% were men. The prevalence of definite or probable FH was 0.85% (95% CI, 0.63-1.06). Among patients with definite or probable FH, 12% had histories of premature cardiovascular disease (vs less than 1% among subjects without FH; P < 0.0001), 70% were treated (13% with high-intensity, 83% with moderate-intensity, and 4% with low-intensity statin therapy), 90% had cholesterol screening within the past 12 months, and 97% were aware of their hypercholesterolemia. None reached the recommended low-density lipoprotein cholesterol (LDL-C) target (< 2.5 or < 1.8 mmol/L for subjects in primary prevention vs in secondary prevention or with diabetes, respectively), with a mean distance to target of 3.0 mmol/L.

CONCLUSIONS

In a sample from the French general population aged 35 to 74 years, the prevalence of FH was close to 1 in 120, and the patients with FH were undertreated.

Autosomal dominant hypercholesterolemia in Catalonia: Correspondence between clinical-biochemical and genetic diagnostics in 967 patients studied in a multicenter clinical setting

BACKGROUND

Autosomal dominant hypercholesterolemia (ADH) is associated with mutations in the low-density lipoprotein (LDL) receptor (LDLR), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin 9 (PCSK9) genes, and it is estimated to be greatly underdiagnosed. The most cost-effective strategy for increasing ADH diagnosis is a cascade screening from mutation-positive probands.

OBJECTIVE

The objective of this study was to evaluate the results from 2008 to 2016 of ADH genetic analysis performed in our clinical laboratory, serving most lipid units of Catalonia, a Spanish region with approximately 7.5 million inhabitants.

METHODS

After the application of the Dutch Lipid Clinic Network (DLCN) clinical diagnostic score for ADH, this information and blood or saliva from 23 different lipid clinic units were investigated in our laboratory. DNA was screened for mutations in LDLR, APOB, and PCSK9, using the DNA-array LIPOchip, the next-generation sequencing SEQPRO LIPO RS platform, and multiplex ligation-dependent probe amplification (MLPA). The Simon Broome Register Group (SBRG) criteria was calculated and analyzed for comparative purposes.

RESULTS

A total of 967 unrelated samples were analyzed. From this, 158 pathogenic variants were detected in 356 patients. The main components of the DLCN criteria associated with the presence of mutation were plasma LDL cholesterol (LDLc), age, and the presence of tendinous xanthomata. The contribution of family history to the diagnosis was lower than in other studies. DLCN and SBRG were similarly useful for predicting the presence of mutation.

CONCLUSION

In a real clinical practice, multicenter setting in Catalonia, the percentage of positive genetic diagnosis in patients potentially affected by ADH was 38.6%. The DLCN showed a relatively low capacity to predict mutation detection but a higher one for ruling out mutation.

Familial hypercholesterolemia: Experience in the Lipid Clinic of Alava

INTRODUCTION

Familial hypercholesterolaemia (FH) is the autosomal dominant genetic disorder most frequently associated with premature cardiovascular disease (CVD).

MATERIAL AND METHODS

A retrospective, observational study was conducted to determine the clinical characteristics, analytical parameters and cardiovascular risk factors of 133 patients with a genetically confirmed diagnosis of FH on follow-up in the Lipid Clinic of Alava.

RESULTS

CVD was observed in 8.30% of the patients (ischaemic heart disease in 100% of the cases). The LDL concentration goal was achieved in 40.6% (45.50% in primary prevention and 27.30% in secondary prevention). The large majority (81.80%) of patients with coronary heart disease (CHD) were male. The odds ratio (OR) of males having CHD compared to females is 4.97 (1.03-23.93, P=.03). The OR of developing CHD in patients with a family history of premature CVD is 6.86 (1.32-35.67, P=.02). A statistically significant association was found between smoking and the risk of CVD (P=.005), and also between having diabetes and the risk of CVD (P=0.0001). If the treatment with statins begins at older than 40 years, the OR of suffering CHD is 6.40 (1.53-26.5) (P=.009). The mean time from diagnosis to the cardiovascular event in the group of ex-smokers is 10.80±5.80 years, and in the non-smoking group it is 17.50±2.50 years (P=.011).

CONCLUSIONS

In our reference population with FH, it was found that there was an increased risk of suffering a cardiovascular event in male patients, with a family history of premature CVD, diabetics, and in those in whom lipid lowering treatment was started after 40 years of age.

Familial Hypercholesterolemia: New Horizons for Diagnosis and Effective Management

Familial hypercholesterolemia (FH) is a common genetic cause of premature cardiovascular disease (CVD). The reported prevalence rates for both heterozygous FH (HeFH) and homozygous FH (HoFH) vary significantly, and this can be attributed, at least in part, to the variable diagnostic criteria used across different populations. Due to lack of consistent data, new global registries and unified guidelines are being formed, which are expected to advance current knowledge and improve the care of FH patients. This review presents a comprehensive overview of the pathophysiology, epidemiology, manifestations, and pharmacological treatment of FH, whilst summarizing the up-to-date relevant recommendations and guidelines. Ongoing research in FH seems promising and novel therapies are expected to be introduced in clinical practice in order to compliment or even substitute current treatment options, aiming for better lipid-lowering effects, fewer side effects, and improved clinical outcomes.

Lipid and lipoprotein parameters for detection of familial hypercholesterolemia in childhood. The DECOPIN Project

BACKGROUND

Familial hypercholesterolaemia (FH) in children is under-detected and is difficult to diagnose in clinical practice. The aim of this study was to evaluate clinical, biochemical and vascular imaging variables in order to detect children and adolescents with FH.

METHODS

A total of 222 children aged 4-18 years old were recruited to participate in a project for the early detection of FH (The DECOPIN Project). They were distributed into 3groups: FH, if genetic study or clinical criteria were positive (n=91); Polygenic hypercholesterolaemia (PH) if LDL-Cholesterol >135mg/dL without FH criteria (n=23), and Control group (CG) if LDL-C <135mg/dL (n=108). Data were collected from family history, anthropometric data, and clinical variables. The usual biochemical parameters, including a complete lipid profile were analysed. The carotid intima-media thickness (cIMT) and thickness of Achilles tendons were determined using ultrasound in all participants.

RESULTS

A total of 91 children had a diagnosis of FH, 23 with PH, and 108 with CG. Children with FH had higher concentrations of total cholesterol, LDL-C, ApoB/ApoA1 ratio, and cholesterol-year score, than the other groups. HDL-C was lower in the FH group than in the CG. Thickness of the Achilles tendon and cIMT did not show any differences between groups, although a greater cIMT trend was observed in the FH group. ApoB/ApoA1 ratio >0.82 was the parameter with the highest sensitivity and specificity to predict the presence of mutation in children with FH.

CONCLUSIONS

Although LDL-C is the main biochemical parameter used to define FH, the ApoB/ApoA1 ratio (>0.82) may be a useful tool to identify children with FH and a positive mutation.

Number of Patients Eligible for PCSK9 Inhibitors Based on Real-world Data From 2.5 Million Patients

INTRODUCTION AND OBJECTIVES

PCSK9 inhibitors (PCSK9i) are safe and effective lipid-lowering drugs. Their main limitation is their high cost. The aim of this study was to estimate the number of patients eligible for treatment with PCSK9i according to distinct published criteria.

METHODS

Data were obtained from the Information System for the Development of Research in Primary Care. Included patients were equal to or older than 18 years and had at least 1 low-density lipoprotein cholesterol measurement recorded between 2006 and 2014 (n = 2 500 907). An indication for treatment with PCSK9i was assigned according to the following guidelines: National Health System, Spanish Society of Arteriosclerosis, Spanish Society of Cardiology, National Institute for Health and Care Excellence, and the European Society of Cardiology/European Atherosclerosis Society Task Force. Lipid-lowering treatment was defined as optimized if it reduced low-density lipoprotein levels by ≥ 50% and adherence was > 80%.

RESULTS

Among the Spanish population aged 18 years or older, the number of possible candidates to receive PCSK9i in an optimal lipid-lowering treatment scenario ranged from 0.1% to 1.7%, depending on the guideline considered. The subgroup of patients with the highest proportion of potential candidates consisted of patients with familial hypercholesterolemia, and the subgroup with the highest absolute number consisted of patients in secondary cardiovascular prevention.

CONCLUSIONS

The number of candidates to receive PCSK9i in conditions of real-world clinical practice is high and varies widely depending on the recommendations of distinct scientific societies.

Lipoprotein profile assessed by 2D-1H-NMR and subclinical atherosclerosis in children with familial hypercholesterolaemia

BACKGROUND AND AIMS

Familial hypercholesterolaemia (FH) is underdiagnosed in children. In addition to lipid concentrations, lipoprotein particle quantity and quality could influence cardiovascular risk. We aimed to perform a comprehensive plasma lipid study, including lipoprotein particle number and size assessment by two-dimensional nuclear magnetic resonance (2D-1H-NMR), in children with FH compared to non-affected children and to evaluate the clinical value of these factors as subclinical atherosclerosis biomarkers.

METHODS

One hundred eighty-three children participating in the broad "Hypercholesterolemia Early Detection Programme" (Decopin Project) were recruited. They were categorized as FH, if they had either a positive genetic test or clinical certainty, or as control children (CCh). Medical history, anthropometry and clinical variables were recorded. Standard biochemical measurements were performed. The lipoprotein profile was studied by 2D-1H-NMR. Carotid intima-media thickness (cIMT) was assessed by sonography in 177 children.

RESULTS

FH children had a significant 36% increase in LDL particles. The small LDL fraction was increased by 33% compared to CCh. The relative relationship between large, medium and small LDL and the mean LDL particle size was similar between FH children and CCh. The total and small LDL particle numbers were directly associated with and contributed to the determination of the mean cIMT according to bivariate and multivariate analyses in FH children.

CONCLUSIONS

The higher cholesterol levels of FH children are due to an overall increased number of all LDL particle subclasses, including a notable 33% increase in small LDL. Total and small LDL particle number shows a good correlation with cIMT in FH children.

Overexpression of tissue-nonspecific alkaline phosphatase (TNAP) in endothelial cells accelerates coronary artery disease in a mouse model of familial hypercholesterolemia

OBJECTIVE

Overexpression of tissue-nonspecific alkaline phosphatase (TNAP) in endothelium leads to arterial calcification in mice. The purpose of this study was to examine the effect of elevated endothelial TNAP on coronary atherosclerosis. In addition, we aimed to examine endogenous TNAP activity in human myocardium.

APPROACH AND RESULTS

A vascular pattern of TNAP activity was observed in human non-failing, ischemic, and idiopathic dilated hearts (5 per group); no differences were noted between groups in this study. Endothelial overexpression of TNAP was achieved in mice harboring a homozygous recessive mutation in the low density lipoprotein receptor (whc allele) utilizing a Tie2-cre recombinase (WHC-eTNAP mice). WHC-eTNAP developed significant coronary artery calcification at baseline compared WHC controls (4312 vs 0μm2 alizarin red area, p<0.001). Eight weeks after induction of atherosclerosis, lipid deposition in the coronary arteries of WHC-eTNAP was increased compared to WHC controls (121633 vs 9330μm2 oil red O area, p<0.05). Coronary lesions in WHC-eTNAP mice exhibited intimal thickening, calcifications, foam cells, and necrotic cores. This was accompanied by the reduction in body weight and left ventricular ejection fraction (19.5 vs. 23.6g, p<0.01; 35% vs. 47%, p<0.05). In a placebo-controlled experiment under atherogenic conditions, pharmacological inhibition of TNAP in WHC-eTNAP mice by a specific inhibitor SBI-425 (30mg*kg-1*d-1, for 5 weeks) reduced coronary calcium (78838 vs.144622μm2) and lipids (30754 vs. 77317μm2); improved body weight (22.4 vs.18.8g) and ejection fraction (59 vs. 47%). The effects of SBI-425 were significant in the direct comparisons with placebo but disappeared after TNAP-negative placebo-treated group was included in the models as healthy controls.

CONCLUSIONS

Endogenous TNAP activity is present in human cardiac tissues. TNAP overexpression in vascular endothelium in mice leads to an unusual course of coronary atherosclerosis, in which calcification precedes lipid deposition. The prevalence and significance of this mechanism in human atherosclerosis requires further investigations.