Management of familial heterozygous hypercholesterolemia: Position Paper of the Polish Lipid Expert Forum

PoLA/CFPiP/PCS/PSLD/PSD/PSH guidelines on diagnosis and therapy of lipid disorders in Poland 2021

In Poland there are still nearly 20 million individuals with hypercholesterolaemia, most of them are unaware of their condition; that is also why only ca. 5% of patients with familial hypercholesterolaemia have been diagnosed; that is why other rare cholesterol metabolism disorders are so rarely diagnosed in Poland. Let us hope that these guidelines, being an effect of work of experts representing 6 main scientific societies, as well as the network of PoLA lipid centers being a part of the EAS lipid centers, certification of lipidologists by PoLA, or the growing number of centers for rare diseases, with a network planned by the Ministry of Health, improvements in coordinated care for patients after myocardial infarction (KOS-Zawał), reimbursement of innovative agents, as well as introduction in Poland of an effective primary prevention program, will make improvement in relation to these unmet needs in diagnostics and treatment of lipid disorders possible.

Pulse wave velocity as a measure of arterial stiffness in patients with familial hypercholesterolemia: a systematic review and meta-analysis

INTRODUCTION

The aim of this meta-analysis was to establish whether vascular pulse wave velocity (PWV) as a measure of arterial stiffness is changed in patients with familial hypercholesterolemia (FH).

MATERIAL AND METHODS

Studies comparing PWV between patients with FH and controls were searched in PubMed-Medline, SCOPUS, Web of Science and Google Scholar databases (up to November 26, 2017). A meta-analysis was conducted using Comprehensive Meta-Analysis V2 software. A random-effects model (using the DerSimonian-Laird method) and the generic inverse variance method were used to compensate for the heterogeneity of studies concerning demographic characteristics and differences in the studies' design.

RESULTS

This meta-analysis of 8 studies involving 317 patients with FH and 244 non-FH individuals did not suggest a significantly altered PWV in FH patients versus controls (weighted mean difference (WMD): 0.17 m/s, 95% confidence interval (CI): -0.31, 0.65, p = 0.489; I ² = 80.15%). The result was robust in the sensitivity analysis and its significance was not influenced after omitting each of the included studies from the meta-analysis. Subanalysis of 6 of these studies which had data on intima-media thickness (IMT) indicated an increased IMT in FH patients when compared with controls (WMD = 0.03 mm, 95% CI: 0.003, 0.06, p = 0.034; I ² = 48.95%). However, the effect size was sensitive to some of the included studies.

CONCLUSIONS

This meta-analysis suggests that FH patients do not have significantly altered PWV when compared with normocholesterolemic individuals. However, a subanalysis of studies in which IMT was measured indicated that IMT is increased in FH patients compared with controls.

The prevalence and management of familial hypercholesterolemia in patients with acute coronary syndrome in the Polish tertiary centre: Results from the TERCET registry with 19,781 individuals

BACKGROUND AND AIMS

The prevalence of familial hypercholesterolemia (FH) is high among patients with stable coronary artery disease (CAD). However, data on FH on admission among patients with acute coronary syndrome (ACS) are still relatively scarce. Therefore, we aimed to assess the prevalence, lipid-lowering therapy and short- and long-term outcomes in patients with FH among ACS patients.

METHODS AND RESULTS

The investigation was performed in a cohort of 19,781 consecutive patients from the TERCET Registry. There were 7319 patients admitted with ACS: 3085 due to STEMI, 2256 due to NSTEMI, and 1978 due to UA. The stable CAD group (n = 12,462) was considered the reference group. Based on the personal and familial history of premature cardiovascular disease and LDL cholesterol concentration, the Dutch Lipid Clinic Network (DLCN) algorithm was used for FH diagnosis. The overall occurrence of probable/definite FH and possible FH was 1.2% and 13.5% respectively. Among patients with ACS, 1.6% had probable/definite FH and 17.0% possible FH. The highest occurrence of FH was observed in the STEMI subgroup (20.6%). Patients with definite and probable FH had higher 30-day mortality than patients without FH (8.2% and 3.8% vs. 2.0%, respectively; p = 0.0052). No significant differences were observed between the FH groups in the 12-, 36- and 60-month follow-up. Propensity-score matching analysis showed that definite/probable FH patients had significantly higher all-cause mortality at 36- and 60-month follow-up in comparison to non-FH subjects (11.4% vs. 4.8% and 19.2% vs. 7.2%, respectively; p ≤ 0.021 for both).

CONCLUSIONS

The prevalence of FH according to the DLCN criteria in the Polish very high-risk population is significantly higher in patients with ACS than in patients with sCAD. FH is a cause of increased all-cause mortality in the long-term follow-up.

Association between phenotypic familial hypercholesterolaemia and telomere length in US adults: results from a multi-ethnic survey

Aims

Familial hypercholesterolaemia (FH) accelerates atherosclerotic cardiovascular disease (ASCVD) and accordingly is the most potent hereditary cause of premature coronary heart disease. The association between telomere length (TL), a biological index of ageing, and FH has not been hitherto investigated. We addressed this question using data from the US National Health and Education National Surveys (NHANES, 1999-2002).

Methods and results

We included individuals, who had TL measurements (with quantitative polymerase chain reaction method) and a phenotypic diagnosis of FH based on the Dutch Lipid Clinic Network (DLCN) criteria. Sample weights were applied for unequal probabilities of selection, non-response bias, and oversampling by complex sample analysis. The adult prevalence of FH in NHANES was 0.43% [95% confidence interval (95% CI) 0.33-0.57]. The frequencies of probable FH (mean DLCN score: 6.2) and definite FH (mean DLCN score: 8.9) were 0.42% (95% CI 0.32-0.48) and 0.03% (95% CI 0.02-0.06), respectively. Subjects with FH had a higher prevalence of non-communicable diseases (hypertension, diabetes 2 type, and obesity) and early atherosclerosis (2.9% in overall population vs. 42.2% in FH). Overall, the mean TL in the non-FH population was 1.09 (95% CI 1.06-1.12) (T/S ratio) and 1.09 (95% CI 1.03-1.12) [(T/S ratio) for total FH]. Telomere length adjusted for age, sex, race, and body mass index was shorter in FH compared with healthy subjects (FH 0.89, 95% CI 0.84-0.93 vs. healthy: 1.05, 95% CI 0.97-1.11 T/S ratio; P < 0.001). Subjects with longer TL (highest quartile) had 12% less chance of having FH compared with those with TL in the lowest quartile (Q1, 95% CI 0.78-0.93).

Conclusions

These preliminary data suggest an association between TL, an index of biological age, and the presence of FH, the most common inherited cause of premature ASCVD. Given our relatively low sample size, the findings need confirmation in larger studies.

Clinical management of heterozygous familial hypercholesterolemia in a Polish outpatient metabolic clinic: a retrospective observational study

INTRODUCTION

There are currently no reports available from a Polish clinical practice on heterozygous familial hypercholesterolemia (HeFH) management. The aim of this study was to test the efficacy of HeFH hypolipidemic treatment in a Polish outpatient metabolic clinic according to treatment targets outlined in the European Atherosclerosis Society (EAS) and European Society of Cardiology (ESC) guidelines.

MATERIAL AND METHODS

This retrospective, observational study was performed on HeFH patients who attended their routine follow-up visits in the metabolic outpatient clinic in the period between April and September 2016. According to EAS/ESC guidelines, the goal and intensity of therapy were assigned individually for every patient based on cardiovascular (CV) risk (high or very high). The treatment target was achievement of low-density lipoprotein cholesterol (LDL-C) levels < 1.8 mmol/l for very high CV risk patients and < 2.6 mmol/l for high CV risk patients. A ≥ 50% decrease in LDL-C over the observation period was an additional outcome measure.

RESULTS

In the overall group of 222 HeFH patients (mean age: 55.2 ±16.2 years, 72% women), LDL-C levels decreased on average by 52.6% (p < 0.001). More than half of the patients were treated with the maximum tolerated dose of statins. A total of 25.2% of patients attained target levels of LDL-C and 55.9% attained a ≥ 50% reduction in its concentration. Despite therapy, significantly elevated post-follow-up levels of LDL-C (> 4.1 mmol/l) remained in 14% of all patients.

CONCLUSIONS

Hypolipidemic therapy according to EAS/ESC guidelines was suboptimal for a significant number of HeFH patients. Additional clinical management should be considered.

The cost-effectiveness of screening strategies for familial hypercholesterolaemia in Poland

BACKGROUND AND AIMS

Familial hypercholesterolaemia (FH) elevates the cholesterol level and increases the risk of coronary events and death. Early detection and treatment reduce this risk. We aimed to determine the cost-effectiveness of FH screening in Poland in children, first job takers, and after an acute coronary syndrome (ACS) event, each followed by a cascade screening in the relatives of the positively-diagnosed subjects.

METHODS

A decision tree was constructed to model the diagnosis process. We considered scenarios with and without genetic testing. A life-time Markov was built to investigate the effectiveness (life years gained, LYG; and quality-adjusted life years, QALY) and cost (public payer perspective) of treatment in FH-affected subjects. The clinical benefits result from early treatment reducing the risk of coronary heart disease (and death, in result). Model parameters were based on published data and experts' opinions. The costs (patients visits, tests, drugs) were estimated from the National Health Fund data and other publicly-available sources.

RESULTS

Screening ACS patients below 55/65 years of age in men/women is the most cost-effective strategy: the cost of one LYG (QALY) amounts to 100 EUR (110 EUR). Removing the age limit or using genetic tests reduced cost-effectiveness; nonetheless, all strategies remained cost effective: the cost of one LYG or QALY was <5040 EUR, much lower than the official threshold of ca. 29,800 EUR/QALY.

CONCLUSIONS

Screening for FH is highly cost-effective in Poland. The strategies are complementary, and using a combination thereof is recommended.

2D-STI combined with gated 99Tcm-MIBI MPI for the diagnosis of myocardial ischemia in hypercholesterolemia patients

This study aimed to investigate the reliability of ultrasound two-dimensional speckle tracking imaging (2D-STI) for the evaluation of myocardial ischemia in familial hypercholesterolemia (FH) patients. We recruited 28 patients clinically diagnosed with homozygous familial hypercholesterolemia (HoFH) and subjected them to 2D-STI, gated transthoracic Doppler echocardiography (TTDE), and ⁹⁹Tc^m-methoxyisobutylisonitrile myocardial perfusion imaging (⁹⁹Tc^m-MIBI MPI). The sensitivity, specificity and diagnostic accordance rate of TTDE and 2D-STI for myocardial ischemia in HoFH patients were compared with the ⁹⁹Tc^m-MIBI scores. According to the diagnosis of ischemia in the three main coronary arteries (LAD, LCX, and RCA) by MPI, patients were further divided into different groups for comparing segmental strain by 2D-STI. The total correlation between TTDE and ⁹⁹Tc^m-MIBI MPI for evaluation of myocardial ischemia was r=0.483 and between 2D-STI and ⁹⁹Tc^m-MIBI MPI was 0.786. The total correlation index for ejection fraction (EF) between TTDE and ⁹⁹Tc^m-MIBI MPI was r=0.606 and for 2D-STI and ⁹⁹Tc^m-MIBI MPI was r=0.919. TTDE indicated that differences among LVDd, LVDs, IVS, LVPW, AO Vmax, PG, E/e', and DT were statistically significant. STI indicated that the total strain of the ischemia group was lower than that of the non-ischemia group. The total systolic strain and total early diastolic strain of the ischemia group were lower than that of the non-ischemia group. TTDE can be used for primary observation and evaluation of ventricular wall ischemia for HoFH patients. Ultrasound 2D-STI is better than TTDE in the evaluation of myocardial ischemia in HoFH patients. Ultrasound 2D-STI shows the same effectiveness as ⁹⁹Tc^m-MIBI MPI for the detection of myocardial ischemia, serving as good tool for prognosis and treatment evaluation in HoFH patients.

PCSK9 inhibitors - from discovery of a single mutation to a groundbreaking therapy of lipid disorders in one decade

Hypercholesterolemia is one of the main risk factors for coronary heart disease and significantly contributes to the high mortality associated with cardiovascular diseases. Statin therapy represents the gold standard in the reduction of low-density lipoprotein cholesterol concentration. Nevertheless, many patients still cannot achieve the recommended target levels, due to either inadequate effectiveness or intolerance of these drugs. Monoclonal antibodies that inhibit proprotein convertase subtilisin/kexin type 9 (PCSK9) have emerged as a promising option in lipid-lowering treatment. After confirmation of their efficacy and safety in clinical trials, evolocumab and alirocumab received approval from the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) for introduction into clinical practice. In this review, we present a history of the development and mechanisms of action, as well as the results of the most important studies concerning PCSK9 inhibitors.

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.

Prevalence of familial hypercholesterolemia: a meta-analysis of six large, observational, population-based studies in Poland

INTRODUCTION

Familial hypercholesterolemia (FH) is a severely underdiagnosed and undertreated genetic disorder. Little is known about regional variation in the prevalence of FH, and information for Central and Eastern Europe (CEE) is scarce. This paper assesses the prevalence of FH and related cardiovascular disease (CVD) risk factors in Poland.

MATERIAL AND METHODS

We performed a meta-analysis of six population-based studies in Poland. The FH was assessed using the Dutch Lipids Clinics Network (DLCN) criteria. The categories "definite" (> 8 points) and "probable" (6-8 points) were combined into "potential FH". Combined estimates of proportions across studies were pooled by meta-analysis with a random effects model.

RESULTS

A total of 37,889 persons aged 20-79 years were included in the analysis. The distribution of DLCN scores was skewed, and there were only 7 cases of definite FH. Prevalence of potential FH was 404/100,000 people (95% CI = 277-531/100,000). Familial hypercholesterolemia was more prevalent in women than in men, and the prevalence was the highest in the age group 45-54 years in men and 55-64 years in women. After adjustment for age and sex, compared to participants with normal cholesterol, persons with potential FH had twice the prevalence of hypertension (p < 0.01); smoking was more prevalent by about 80% (p < 0.01) and hypertriglyceridemia was nine times more frequent (p < 0.001). There was no difference in the prevalence of low high-density lipoprotein (HDL)-cholesterol or diabetes.

CONCLUSIONS

We believe that our study might facilitate the planning of a strategy to manage the disease at a population level, i.e. to develop a national strategy for the detection, diagnosis, and treatment of FH.

The genetic spectrum of familial hypercholesterolemia in south-eastern Poland

BACKGROUND

Familial hypercholesterolemia (FH) is a common autosomal dominant disorder with a frequency of 1 in 200 to 500 in most European populations. Mutations in LDLR, APOB and PCSK9 genes are known to cause FH. In this study, we analyzed the genetic spectrum of the disease in the understudied Polish population.

MATERIALS AND METHODS

161 unrelated subjects with a clinical diagnosis of FH from the south-eastern region of Poland were recruited. High resolution melt and direct sequencing of PCR products were used to screen 18 exons of LDLR, a region of exon 26 in the APOB gene and exon 7 of PCSK9. Multiplex ligation-dependent probe amplification (MLPA) was performed to detect gross deletions and insertions in LDLR. Genotypes of six LDL-C raising SNPs were used for a polygenic gene score calculation.

RESULTS

We found 39 different pathogenic mutations in the LDLR gene with 10 of them being novel. 13 (8%) individuals carried the p.Arg3527Gln mutation in APOB, and overall the detection rate was 43.4%. Of the patients where no mutation could be found, 53 (84.1%) had a gene score in the top three quartiles of the healthy comparison group suggesting that they have a polygenic cause for their high cholesterol.

CONCLUSIONS

These results confirm the genetic heterogeneity of FH in Poland, which should be considered when designing a diagnostic strategy in the country. As in the UK, in the majority of patients where no mutation can be found, there is likely to be a polygenic cause of their high cholesterol level.

Proprotein convertase subtilisin/kexin 9 inhibitors: an emerging lipid-lowering therapy?

Proprotein convertase subtilisin/kexin 9 (PCSK9) is part of the proteinase K subfamily of subtilases and plays a key role in lipid metabolism. It increases degradation of the low-density lipoprotein receptor (LDL-R), modulates cholesterol metabolism and transport, and contributes to the production of apolipoprotein B (apoB) in intestinal cells. Exogenous PCSK9 modifies the activity of 3-hydroxy-3-methylglutaryl-coenzyme A reductase and acyl coenzyme A:cholesterol acyltransferase and enhances secretion of chylomicrons by modulating production of lipids and apoB-48. Statins increase PCSK9 messenger RNA expression and attenuate the capacity to increase LDL-R levels. Therefore, the inhibition of PCSK9 in combination with statins provides a promising approach for lowering low-density lipoprotein cholesterol (LDL-C) concentrations. This review will address new therapeutic strategies targeting PCSK9, including monoclonal antibodies, antisense oligonucleotides, small interfering RNAs, and other small molecule inhibitors. Further studies are still needed to determine the efficacy and safety of the PCSK9 inhibitors not only to decrease LDL-C but also to investigate the potential underlying mechanisms involved and to test whether these compounds actually reduce cardiovascular end points and mortality.

Influence of metabolic syndrome superposition on familial combined hyperlipoproteinemia cardiovascular complication rate

INTRODUCTION

Familial combined hyperlipoproteinemia (FCHL) is a very common and aggressive genetic mixed hyperlipoproteinemia, with many features similar to that of the metabolic syndrome (MS). We aimed to evaluate whether the presence of the MS per se could account for a significant part of the elevated cardiovascular disease (CVD) risk associated with FCHL.

MATERIAL AND METHODS

A retrospective cross-sectional evaluation of MS features' influence on CVD prevalence in a large sample of adult Italian FCHL affected patients (64 familial clusters; 867 subjects) was carried out.

RESULTS

Age is associated with early cardiovascular complications, both in men (OR 1.08, 95% CI: 1.05-1.11, p < 0.0001) and in women (OR 1.09, 95% CI: 1.04-1.13, p = 0.0001). No MS component appears to be related to cardiovascular complications in men, whilst only low plasma high-density lipoprotein cholesterol (HDL-C) shows such a relation in women. Among non-MS parameters, only low-density lipoprotein cholesterol (LDL-C) and lipoprotein(a) (Lp(a)) plasma levels are significantly associated with early cardiovascular complications in male FCHL patients (LDL-C: OR 2.24, 95% CI: 1.02-4.91, p = 0.04; Lp(a): OR 4.64, 95% CI: 1.85-11.62, p = 0.001), but not in women (LDL-C: OR 1.83, 95% CI 0.53-6.34, p = 0.34; Lp(a): OR 3.65, 95% CI: 0.89-14.97, p = 0.07).

CONCLUSIONS

Our data support the hypothesis that MS is not associated with a higher prevalence of cardiovascular complications in FCHL affected subjects, probably because of the strongest risk increase associated with the FCHL itself.