Cascade Screening in Familial Hypercholesterolemia: Advancing Forward

Is Family History for the Management of Cardiovascular Health in Youth Still Relevant in Clinical Practice?

PURPOSE OF REVIEW

Family history of premature cardiovascular disease is a strong predictor of individual cardiovascular risk. However, family history is not always available and not always reliable. Roughly 80% of health outcomes are influenced not by genetic risk but by societal factors, including adverse health behaviors and environment. Furthermore, in the present age of genetic testing, laboratory evaluations, and imaging, a key question remains: What is the contemporary relevance of family history screening in the management of cardiovascular disease in youth?

RECENT FINDINGS

Knowledge of an individual's family history can help clinicians identify not only inherited risk but also familial clustering of unhealthy behaviors and environmental adversity contributing to enhanced cardiovascular disease risk in youth. For those at greatest risk, prevention strategies can be applied sooner and more conservatively. Integrating family history into clinical practice is crucial for cardiovascular risk assessment and for optimizing outcomes, but, in some cases, is more reflective of social factors.

Synthesized economic evidence on the cost-effectiveness of screening familial hypercholesterolemia

BACKGROUND

Familial hypercholesterolemia (FH) is a prevalent genetic disorder with global implications for severe cardiovascular diseases. Motivated by the growing recognition of the need for early diagnosis and treatment of FH to mitigate its severe consequences, alongside the gaps in understanding the economic implications and equity impacts of FH screening, this study aims to synthesize the economic evidence on the cost-effectiveness of FH screening and to analyze the impact of FH screening on health inequality.

METHODS

We conducted a systematic review on the economic evaluations of FH screening and extracted information from the included studies using a pre-determined form for evidence synthesis. We synthesized the cost-effectiveness components involving the calculation of synthesized incremental cost-effectiveness ratios (ICERs) and net health benefit (NHB) of different FH screening strategies. Additionally, we applied an aggregate distributional cost-effectiveness analysis (DCEA) to assess the impact of FH screening on health inequality.

RESULTS

Among the 19 studies included, over half utilized Markov models, and 84% concluded that FH screening was potentially cost-effective. Based on the synthesized evidence, cascade screening was likely to be cost-effective, with an ICER of $49,630 per quality-adjusted life year (QALY). The ICER for universal screening was $20,860 per QALY as per evidence synthesis. The aggregate DCEA for six eligible studies presented that the incremental equally distributed equivalent health (EDEH) exceeded the NHB. The difference between EDEH and NHB across the six studies were 325, 137, 556, 36, 50, and 31 QALYs, respectively, with an average positive difference of 189 QALYs.

CONCLUSIONS

Our research offered valuable insights into the economic evaluations of FH screening strategies, highlighting significant heterogeneity in methods and outcomes across different contexts. Most studies indicated that FH screening is cost-effective and contributes to improving overall population health while potentially reducing health inequality. These findings offer implications that policies should promote the implementation of FH screening programs, particularly among younger population. Optimizing screening strategies based on economic evidence can help identify the most effective measures for improving health outcomes and maximizing cost-effectiveness.

Challenges faced by patients with dyslipidemia and systemic arterial hypertension in Brazil: a design of the patient journey

BACKGROUND AND OBJECTIVE

Non-communicable diseases like systemic arterial hypertension (SAH) and dyslipidemia are poorly studied in terms of patient journey aspects. This semi-systematic review provides evidence synthesis for the management of SAH and dyslipidemia in Brazil and also discusses challenges faced by patients at the local level along with a suggested care approach by local experts.

METHODS

A semi-systematic review using both structured literature databases (Embase and Medline) and unstructured scientific records (WHO, IPD, MOH and Google) on hypertension and dyslipidemia in the English language from 2010 to 2019 was performed by reviewers. After two-level screening based on pre-defined criteria, patient journey touchpoints and prevalence information were extracted from the included articles. Data gaps were bridged through the insights of local experts.

RESULTS

Prevalence of hypertension and dyslipidemia in Brazil were 23% and 40.8%, respectively. Awareness of dyslipidemia was found in a larger proportion (58.1%) than in SAH (22.2%). Similarly, screening for hypertension (97%) and dyslipidemia (55.4%) were found to be effective, while treatment was (62.9%) and (30.0%) for hypertension and dyslipidemia, respectively.

CONCLUSION

There were important gaps on patient awareness and treatment of dyslipidemia and hypertension. Limited patient education, regional disease distribution, and treatment allocation, along with limited resources for diagnosis and treatment are the key challenges.

Cardiovascular Risk Misperception and Low Awareness of Familial Hypercholesterolemia in Individuals with Severe Hypercholesterolemia

Fundamento

Indivíduos com hipercolesterolemia grave apresentam alto risco de desenvolver doença cardiovascular aterosclerótica (DCVA). Muitos deles apresentam hipercolesterolemia familiar (HF).

Objetivos

Avaliar, a partir da perspectiva dos pacientes, o nível de conhecimento sobre a hipercolesterolemia grave, especialmente em relação a HF, DCVA, percepção de risco, desempenho do rastreamento em cascata e tratamento de indivíduos participantes de um programa de avaliação periódica de saúde.

Métodos

De um banco de dados de 70.000 brasileiros avaliados entre 2006 e 2016, 1.987 (2,8%) atenderam aos critérios de inclusão (idade ≥ 18 anos e LDL-C ≥ 190 mg/dL ou ≥ 160 mg/dL se sem uso de estatinas ou em terapia com estatinas, respectivamente). Desses, 200 foram aleatoriamente convidados a preencher um questionário extenso. A HF foi diagnosticada em caso de suspeita pelo médico responsável.

Resultados

Embora 97% da amostra (48±9 anos; 16% do sexo feminino; 95% com ensino superior; 88% em prevenção primária; LDL-C 209±47 mg/dL) tenha apresentado hipercolesterolemia grave, apenas 18% e 29,5% se consideravam de alto risco para desenvolver DCVA e relataram saber sua meta recomendada de LDL-C, respectivamente. Em relação à possibilidade de o colesterol alto ser uma doença hereditária, 58% relataram conhecimento sobre o fato; 24,5% (n = 49) já tinham ouvido falar em HF; e apenas 14% (n = 20) foram previamente identificados com suspeita de HF (idade ao diagnóstico de HF: 35±12 anos; 79% e 31% foram diagnosticados com > 30 e > 40 anos, respectivamente). Apenas 2,5% foram submetidos a testes genéticos; 17%, à rastreamento em cascata; e 17% não faziam uso de tratamento farmacológico.

Conclusões

Identificou-se uma importante lacuna na percepção de risco, no controle do colesterol e em aspectos relacionados à HF em indivíduos com hipercolesterolemia grave. (Arq Bras Cardiol. 2021; [online].ahead print, PP.0-0)

A catalog of the pathogenic mutations of LDL receptor gene in Japanese familial hypercholesterolemia

BACKGROUND

Little data exist on the pathogenic mutations of LDL receptor in Japanese familial hypercholesterolemia (FH).

OBJECTIVE

We aimed to catalog the pathogenic mutations of LDL receptor gene in the 2 major Japanese FH-care centers (Kanazawa University and National Cerebral and Cardiovascular Center Research Institute), where genetic testing of FH has been performed centrally on requests from institutes all over Japan during more than past 2 decades.

METHODS

796 FH subjects from 472 families who had nonsynonymous mutations in LDL receptor gene were included in this study. Genetic mutations were analyzed for mutations by Sanger sequencing as well as by multiplex ligation probe dependent amplification technique for large rearrangements. Pathogenic mutations were defined either as 1) protein truncated variants, 2) registered as pathogenic in ClinVar, or Human Gene Mutation Database (HGMD), or meet the criteria of American College of Medical Genetics and Genomics guideline, or 3) CADD score > 10.

RESULTS

We found 138 different mutations. Among them, 132 mutations were considered as pathogenic, including 19 large rearrangement mutations. However, 6 missense mutations were classified as variants of unknown significance. A single mutation accounted for as much as 41% of the FH subjects recruited from Kanazawa University mainly due to founder gene effect, whereas many singleton mutations were found from National Cerebral and Cardiovascular Center Research Institute located in Osaka.

CONCLUSIONS

We provided the largest catalog of pathogenic mutations of LDL receptor gene in Japanese FH. This could aid to determine the pathogenicity of the LDL receptor genetic mutations not only in Japanese but also in other ethnicities.

Early diagnosis and treatment of familial hypercholesterolemia

If undiagnosed and untreated, familial hypercholesterolemia can lead to serious cardiac complications, such as premature atherosclerotic cardiovascular disease. NPs should be familiar with the clinical presentation of this inherited metabolic disease to diagnose patients as early as possible and promptly begin treatment that may include lifestyle changes, statin therapy, and/or nonstatin therapy.

Health related quality of life in individuals at high risk for familial hypercholesterolemia undergoing genetic cascade screening in Brazil

BACKGROUND AND AIMS

Familial hypercholesterolemia (FH) is a genetic disorder associated with high risk of early major cardiovascular events (MACE) that can impact the health related quality of life (HRQoL), however, this association is unclear. This study evaluated HRQoL in index cases (IC) and first-degree relatives (FDR) of individuals at high risk of FH undergoing genetic cascade screening.

METHODS

Data collection was performed before awareness of molecular diagnosis results. Individuals were divided into four groups according to the molecular diagnosis: IC with (IC+) and without (IC-) identified mutations (n = 93 and n = 175, respectively), and affected (FDR+, n = 231) and non-affected (FDR-, n = 159) FDR of IC+. HRQoL measurements, mental (MCS) and physical component (PCS) scores were carried out with SF-12 questionnaire. Associations were tested by generalized linear models.

RESULTS

The mean age was 49 ± 15 years, 42.2% were men, MACE had occurred in 30.7%. Overall, both PCS and MCS did not differ between FH and non-FH individuals, however, IC trended to have lower PCS independent of FH presence (p=0.003). Lower PCS were associated with female sex (p=0.018), lower education (p<0.001), professional inactivity (p=0.028), previous MACE occurrence (p<0.001), hypertension (p=0.016), depression (p<0.001) and obesity (p<0.001). Lower MCS were associated with female sex (p=0.009), previous MACE occurrence (p=0.034), depression (p<0.001) and smoking (p=0.009). Neither the presence of FH causing mutations nor pharmacological lipid lowering treatment was associated with HRQoL.

CONCLUSIONS

HRQoL is not reduced in both IC and FDR FH individuals in comparison with their non-affected counterparts. Previous MACE and co-morbidities are associated with reduced HRQoL.

[Diagnosis and Treatment of Familial Hypercholesterolemia]

Diagnosis and Treatment of Familial Hypercholesterolemia Abstract. Familial hypercholesterolemia secondary to heterozygous mutations in the LDL receptor, Apolipoprotein B or PCSK9 gene is characterized by 2- to 3-fold elevated LDL cholesterol levels, premature atherosclerosis and extravascular cholesterol deposits (tendon xanthomata, corneal arcus). The same phenotype may occur if a person carries several LDL cholesterol rising polymorphisms (polygenic FH). Primary prevention with statins has been shown to dramatically reduce the cardiovascular burden in patients with the disease. However, it is estimated that less than 10 % of affected subjects in Switzerland have received the diagnosis, and undertreatment is frequent. Thus, clinical cardiovascular events are still the first manifestation of the disease in many cases. A correct diagnosis in index patients and cascade screening of families are mandatory to identify and treat patients before they suffer the sequelae of untreated severe hypercholesterolemia. In patients with clinical cardiovascular disease combination lipid lowering treatment with potent statins, ezetimibe and the newly available PCSK9 inhibitors will successfully lower LDL cholesterol to normal or even target levels.

Risk Communication in Families of Children with Familial Hypercholesterolemia: Identifying Motivators and Barriers to Cascade Screening to Improve Diagnosis at a Single Medical Center

Familial hypercholesterolemia (FH) is severely underdiagnosed in the USA; yet, factors influencing family notification about risk for FH in the US pediatric setting have not been well elucidated. Most previous research on these factors has occurred in adult patient populations in European countries with organized cascade screening programs; therefore, we sought to characterize parent experiences with cascade screening in the US pediatric setting. A quantitative survey measuring family notification of FH risk information was administered to 38 parents of children with FH identified within a pediatric cardiology clinic. Participants were also asked if family notification was impacted by intrapersonal, interpersonal, institutional, community, and public policy factors identified previously in other populations. Notification of at least one of the proband's living grandparents or aunts/uncles was reported by 76% (n = 25/33) and 71% (n = 24/34) of participants, respectively. The most common reason for notification was to protect relatives from heart disease. Two of the most common reasons participants did not notify relatives were a lack of information about FH and concern that the relative would have difficulty understanding the information. Yet, only a minority of participants (39%) accessed institutional resources such as educational materials to share with relatives or assistance drafting a family letter that could address these barriers. Based on the identified barriers and motivators for family communication, we suggest facilitators to improve implementation of cascade screening.

Guidance for Pediatric Familial Hypercholesterolemia 2017

This paper describes consensus statement by Joint Working Group by Japan Pediatric Society and Japan Atherosclerosis Society for Making Guidance of Pediatric Familial Hypercholesterolemia (FH) in order to improve prognosis of FH.FH is a common genetic disease caused by mutations in genes related to low density lipoprotein (LDL) receptor pathway. Because patients with FH have high LDL cholesterol (LDL-C) levels from the birth, atherosclerosis begins and develops during childhood which determines the prognosis. Therefore, in order to reduce their lifetime risk for cardiovascular disease, patients with FH need to be diagnosed as early as possible and appropriate treatment should be started.Diagnosis of pediatric heterozygous FH patients is made by LDL-C ≥140 mg/dL, and family history of FH or premature CAD. When the diagnosis is made, they need to improve their lifestyle including diet and exercise which sometimes are not enough to reduce LDL-C levels. For pediatric FH aged ≥10 years, pharmacotherapy needs to be considered if the LDL-C level is persistently above 180 mg/dL. Statins are the first line drugs starting from the lowest dose and are increased if necessary. The target LDL-C level should ideally be ＜140 mg/dL. Assessment of atherosclerosis is mainly performed by noninvasive methods such as ultrasound.For homozygous FH patients, the diagnosis is made by existence of skin xanthomas or tendon xanthomas from infancy, and untreated LDL-C levels are approximately twice those of heterozygous FH parents. The responsiveness to pharmacotherapy should be ascertained promptly and if the effect of treatment is not enough, LDL apheresis needs to be immediately initiated.

Familial Screening for Left-Sided Congenital Heart Disease: What Is the Evidence? What Is the Cost?

Since the American Heart Association’s recommendation for familial screening of adults with congenital heart disease for bicuspid aortic valve, similar recommendations for other left-sided heart defects, such as hypoplastic left heart syndrome (HLHS), have been proposed. However, defining at-risk populations for these heart defects based on genetics is less straightforward due to the wide variability of inheritance patterns and non-genetic influences such as environmental and lifestyle factors. We discuss whether there is sufficient evidence to standardize echocardiographic screening for first-degree relatives of children diagnosed with HLHS. Due to variations in the inclusion of cardiac anomalies linked to HLHS and the identification of asymptomatic individuals with cardiac malformations, published studies are open to interpretation. We conclude that familial aggregation of obstructive left-sided congenital heart lesions in families with history of HLHS is not supported and recommend that additional screening should adopt a more conservative definition of what truly constitutes this heart defect. More thorough consideration is needed before embracing familial screening recommendations of families of patients with HLHS, since this could inflict serious costs on healthcare infrastructure and further burden affected families both emotionally and financially.

Familial hypercholesterolaemia

Familial hypercholesterolaemia is a common inherited disorder characterized by abnormally elevated serum levels of low-density lipoprotein (LDL) cholesterol from birth, which in time can lead to cardiovascular disease (CVD). Most cases are caused by autosomal dominant mutations in LDLR, which encodes the LDL receptor, although mutations in other genes coding for proteins involved in cholesterol metabolism or LDLR function and processing, such as APOB and PCSK9, can also be causative, although less frequently. Several sets of diagnostic criteria for familial hypercholesterolaemia are available; common diagnostic features are an elevated LDL cholesterol level and a family history of hypercholesterolaemia or (premature) CVD. DNA-based methods to identify the underlying genetic defect are desirable but not essential for diagnosis. Cascade screening can contribute to early diagnosis of the disease in family members of an affected individual, which is crucial because familial hypercholesterolaemia can be asymptomatic for decades. Clinical severity depends on the nature of the gene that harbours the causative mutation, among other factors, and is further modulated by the type of mutation. Lifelong LDL cholesterol-lowering treatment substantially improves CVD-free survival and longevity. Statins are the first-line therapy, but additional drugs, such as ezetimibe, bile acid sequestrants, PCSK9 inhibitors and other emerging therapies, are often required.

Phenotype vs. genotype in severe familial hypercholesterolemia: what matters most for the clinician?

PURPOSE OF REVIEW

Familial hypercholesterolemia is associated with a high lifetime risk of atherosclerotic cardiovascular disease (ASCVD). However, this risk is variable. This review evaluates recent evidence related to ASCVD risk stratification in familial hypercholesterolemia considering aspects of phenotype and genotype.

RECENT FINDINGS

The heterogeneity in clinical, laboratory characteristics, and in ASCVD risk in both homozygous and heterozygous familial hypercholesterolemia individuals in part can be attributed to the type of molecular defect. In most individuals with LDL cholesterol more than 190 mg/dl, a familial hypercholesterolemia-causing variant is not encountered, however, when present, a variant implicates an even higher ASCVD risk for such individuals. Previous ASCVD events, elevated blood lipoprotein(a), cutaneous markers of cholesterol deposit are among other factors that indicate a higher ASCVD risk in familial hypercholesterolemia individuals underlying a more severe form of the phenotype.

SUMMARY

Both clinical and genetic parameters help identify higher ASCVD risk among severe familial hypercholesterolemia individuals.

The panorama of familial hypercholesterolemia in Latin America: a systematic review

The burden caused by familial hypercholesterolemia (FH) varies among countries and ethnic groups. The prevalence and characteristics of FH in Latin American (LA) countries is largely unknown. We present a systematic review (following the PRISMA statement) of FH in LA countries. The epidemiology, genetics, screening, management, and unique challenges encountered in these countries are discussed. Published reports discussing FH in Hispanic or LA groups was considered for analysis. Thirty studies were included representing 10 countries. The bulk of the data was generated in Brazil and Mexico. Few countries have registries and there was little commonality in FH mutations between LA countries. LDL receptor mutations predominate; APOB and PCSK9 mutations are rare. No mutation was found in an FH gene in nearly 50% of cases. In addition, some country-specific mutations have been reported. Scant information exists regarding models of care, cascade screening, cost, treatment effectiveness, morbidity, and mortality. In conclusion, FH is largely underdiagnosed and undertreated in the LA region. The genetic admixture with indigenous populations, producing mestizo's groups, may influence the mutational findings in Latin America. Potential opportunities to close gaps in knowledge and health care are identified.