Reclassifying Risk in Familial Hypercholesterolemia

Retinal Microvascular Changes in Familial Hypercholesterolemia: Analysis with Swept-Source Optical Coherence Tomography Angiography

Familial hypercholesterolemia (FH) is a common but underdiagnosed genetic disorder affecting cholesterol metabolism, leading to atherosclerotic disease. The relationship between retinal microvascular changes and the presence of atheroma in patients with FH (FH group), and in comparison to volunteers without FH (CT group), needs further investigation. This cross-sectional study was conducted in a university hospital between October 1, 2020 and May 31, 2021. Cardiovascular data, including the Coronary Artery Calcium (CAC) score, were recorded for FH patients. Macula angiograms were acquired using swept-source optical coherence tomography angiography (SS OCT-A) to analyze both the superficial capillary plexus (SCP) and deep capillary plexus (DCP). A total of 162 eyes of 83 patients were enrolled in the FH group and 121 eyes of 78 volunteers in the CT group. A statistically significant association was found between the CAC score and both vessel density (β = −0.002 [95% CI, −0.004; −0.0005], p = 0.010) and vessel length (β = −0.00005 [95% CI, −0.00008; −0.00001], p = 0.010) in the DCP. The FH group had a significantly lower foveal avascular zone circularity index than the CT group in multivariate analysis (0.67 ± 0.16 in the FH group vs. 0.72 ± 0.10 in the CT group, β = 0.04 [95% CI, 0.002; 0.07], p = 0.037). Retinal microvascularization is altered in FH and retinal vascular densities are modified according to the CAC score.

Current Approach to the Diagnosis and Treatment of Heterozygote and Homozygous FH Children and Adolescents

Purpose of Review

To elucidate the current approach of care in pediatric patients with familial hypercholesterolemia (FH). We sought an answer to the question whether the advances and major changes in lipid management are relevant and apply to children and adolescents.

Recent Findings

Latest research findings clearly demonstrate that lowering cholesterol levels at a young age prevents vascular atherosclerotic changes and decreases cardiovascular events in adulthood and emphasizes the importance of early detection and intervention in the pediatric FH patients group.

Summary

FH is a common genetic disease caused by mutations in genes associated with the metabolism of low-density lipoproteins (LDL). The hallmark of FH is elevated LDL cholesterol (LDL-C) levels from birth and premature atherosclerotic cardiovascular disease (ASCVD). Often FH is either undiagnosed or diagnosed with a considerable delay, leading to vascular atherosclerotic changes and cardiovascular disease. Prompt identification of FH subjects is essential, to initiate early preventive measures. Safe and efficient pharmacological agents are approved for use in children and adolescents. Statins are the first line of therapy, in combination of ezetimibe. Unfortunately, these drugs do not warrant the achievement of therapeutic target, especially in HoFH patient. In the latter, lipoprotein apheresis (LA), which has been shown to be safe and effective, is strongly recommended. Finally, the new drugs still under study will allow a multimodal customized treatment. Lowering cholesterol levels at a young age hinders vascular atherosclerotic changes decreasing cardiovascular events in adulthood. Therefore, early detection, diagnosis, and intervention in FH patients are priority objectives.

Role of coronary artery calcium score in the primary prevention of cardiovascular disease

First developed in 1990, the Agatston coronary artery calcium (CAC) score is an international guideline-endorsed decision aid for further risk assessment and personalized management in the primary prevention of atherosclerotic cardiovascular disease. This review discusses key international studies that have informed this 30 year journey, from an initial coronary plaque screening paradigm to its current role informing personalized shared decision making. Special attention is paid to the prognostic value of a CAC score of zero (the so called "power of zero"), which, in a context of low estimated risk thresholds for the consideration of preventive therapy with statins in current guidelines, may be used to de-risk individuals and thereby inform the safe delay or avoidance of certain preventive therapies. We also evaluate current recommendations for CAC scoring in clinical practice guidelines around the world, and past and prevailing barriers for its use in routine patient care. Finally, we discuss emerging approaches in this field, with a focus on the potential role of CAC informing not only the personalized allocation of statins and aspirin in the general population, but also of other risk-reduction therapies in special populations, such as individuals with diabetes and people with severe hypercholesterolemia.

The evolving role of coronary artery calcium in preventive cardiology 30 years after the Agatston score

PURPOSE OF REVIEW

On the brink of the 30th anniversary of the Agatston score we summarize the epidemiological data that shaped the recommendations relevant to coronary artery calcium (CAC) included in the 2018/2019 US and European guidelines for the primary prevention of atherosclerotic cardiovascular disease (ASCVD). We also discuss the implications of novel CAC research conducted in asymptomatic populations within the past 2 years.

RECENT FINDINGS

Based on a wealth of observational evidence, CAC has emerged as a mainstay in personalized risk assessment and is now endorsed as a class IIa tool in both US and European guidelines. In the past 2 years, data supporting the prognostic power of CAC has kept mounting, with longer term follow-up data now available. CAC has been evaluated in a variety of patient populations including individuals with severe hypercholesterolemia, diabetes mellitus and younger adults with family history of ASCVD, in all of whom it may be able to inform a more personalized management. Novel CAC scoring approaches are also discussed.

SUMMARY

Despite a strong endorsement in recent guidelines, active research in the last 2 years has provided further insights on the potential utility of CAC in informing a more individualized preventive management in broader populations.

Montreal-FH-SCORE Predicts Coronary Artery Calcium Score in Patients With Familial Hypercholesterolemia

BACKGROUND

Familial hypercholesterolemia (FH) is a monogenic disease characterized by a high concentration of low-density lipoprotein cholesterol. This population is considered to be at high cardiovascular risk; however, disease evolution remains heterogeneous among individuals. The coronary artery calcium (CAC) score is currently the best predictor of incidental major cardiovascular events in primary prevention in the general population. Few studies have described the CAC score in FH populations.

METHODS

The objective of our study was to determine the predictors of the CAC score in FH patients. We retrospectively studied FH patients followed at the Montreal Clinical Research Institute (IRCM) Lipid Clinic who had a cardiac scan for CAC score, using the Agatston method, between 2013 and 2019.

RESULTS

Final analysis included 62 FH patients. Mean age was 48 ± 14 years old, and 48% were men. Overall, 25 patients had a CAC score of 0 (40%), and 37 patients had a nonzero CAC score (60%). Sex, age, Montreal-FH-SCORE (MFHS), waist circumference, and statin exposure in years were significant predictors (P ≤ 0,05) of a nonzero CAC score in a univariate model. MFHS was the only factor that remained significant in a multivariate model (odds ratio 1.34, 95% confidence interval 1.11-1.61, P = 0.002).

CONCLUSIONS

In conclusion, we found that MFHS, which includes traditional cardiovascular risk factors, was a predictor of a nonzero CAC score in FH patients. This finding suggests that MFHS may play a role in determining the cardiovascular risk and therefore the intensity of treatment in FH patients.

Genetic Testing and Risk Scores: Impact on Familial Hypercholesterolemia

Familial Hypercholesterolemia (FH) is an inherited lipid disorder affecting 1 in 220 individuals resulting in highly elevated low-density lipoprotein levels and risk of premature coronary disease. Pathogenic variants causing FH typically involve the LDL receptor (LDLR), apolipoprotein B-100 (APOB), and proprotein convertase subtulisin/kexin type 9 genes (PCSK9) and if identified convey a risk of early onset coronary artery disease (ASCVD) of 3- to 10-fold vs. the general population depending on the severity of the mutation. Identification of monogenic FH within a family has implications for family-based testing (cascade screening), risk stratification, and potentially management, and it has now been recommended that such testing be offered to all potential FH patients. Recently, robust genome wide association studies (GWAS) have led to the recognition that the accumulation of common, small effect alleles affecting many LDL-c raising genes can result in a clinical phenotype largely indistinguishable from monogenic FH (i.e., a risk of early onset ASCVD of ~3-fold) in those at the extreme tail of the distribution for these alleles (i.e., the top 8% of the population for a polygenic risk score). The incorporation of these genetic risk scores into clinical practice for non-FH patients may improve risk stratification but is not yet widely performed due to a less robust evidence base for utility. Here, we review the current status of FH genetic testing, potential future applications as well as challenges and pitfalls.