It is Time to Screen for Homozygous Familial Hypercholesterolemia in the United States.

Homozygous familial hypercholesterolemia (HoFH) is an ultra-rare inherited condition that affects approximately one in 300,000 people. The disorder is characterized by extremely high, life-threatening levels of low-density lipoprotein (LDL) cholesterol from birth, leading to significant premature cardiovascular morbidity and mortality, if left untreated. Homozygous familial hypercholesterolemia is severely underdiagnosed and undertreated in the United States (US), despite guidelines recommendations for universal pediatric lipid screening in children aged 9-11. Early diagnosis and adequate treatment are critical in averting premature cardiovascular disease in individuals affected by HoFH. Yet, an unacceptably high number of people living with HoFH remain undiagnosed, misdiagnosed, and/or receive a late diagnosis, often after a major cardiovascular event. The emergence of novel lipid-lowering therapies, along with the realization that diagnosis is too often delayed, have highlighted an urgency to implement policies that ensure timely detection of HoFH in the US. Evidence from around the world suggests that a combination of universal pediatric screening and cascade screening strategies constitutes an effective approach to identifying heterozygous familial hypercholesterolemia (HeFH). Nevertheless, HoFH and its complications manifest much earlier in life compared to HeFH. To date, little focus has been placed on the detection of HoFH in very young children and/or infants. The 2023 Updated European Atherosclerosis Society Consensus Statement on HoFH has recommended, for the first time, broadening pediatric guidelines to include lipid screening of newborn infants. Some unique aspects of HoFH need to be considered before implementing newborn screening. As such, insights from pilot studies conducted in Europe may provide some preliminary guidance. Our paper proposes a set of actionable measures that states can implement to reduce the burden of HoFH. It also outlines key research and policy gaps that need to be addressed in order to pave the way for universal newborn screening of HoFH in the US.

Newborn screening for lipid disorders.

PURPOSE OF REVIEW: Newborn screening is one of the most successful public health programs of the last century and offers unparalleled access to universal screening for a variety of metabolic and other disorders. Interest in development of newborn screening for lipid disorders has intensified in recent years. Screening newborns for lipid disorders has important implications for the health of the newborn as well as their relatives, and in the case of more common lipid disorders like familial hypercholesterolemia, could have important public health implications. RECENT FINDINGS: Recent studies have demonstrated feasibility of measuring biomarkers for heterozygous familial hypercholesterolemia from newborn screening dried blood spot specimens. Another lipid disorder, cerebrotendinous xanthomatosis, is currently amenable to newborn screening utilizing currently available assays. New research in next-generation sequencing as a primary screen in newborns will also identify both common and rare lipid disorders in newborns. SUMMARY: Historically, newborn screening for lipid disorders was not done for many reasons, but new research has developed testing methods that may successfully identify common and rare lipid disorders. This will impact the health of the newborn but could also impact family members and public health.

Toward a Roadmap for Best Practices in Pediatric Preventive Cardiology: A Science Advisory From the American Heart Association.

Cardiovascular disease risk factors are highly prevalent among youth in the United States and Canada. Pediatric preventive cardiology programs have independently developed and proliferated to address cardiovascular risk factors in youth, but there is a general lack of clarity on best practices to optimize and sustain desired outcomes. We conducted surveys of pediatric cardiology division directors and pediatric preventive cardiology clinicians across the United States and Canada to describe the current landscape and perspectives on future directions for the field. We summarize the data and conclude with a call to action for various audiences who seek to improve cardiovascular health in youth, reduce the burden of premature cardiovascular disease, and increase healthy longevity. We call on heart centers, hospitals, payers, and policymakers to invest resources in the important work of pediatric preventive cardiology programs. We urge professional societies to advocate for pediatric preventive cardiology and provide opportunities for training and cross-pollination across programs. We encourage researchers to close evidence gaps. Last, we invite pediatric preventive cardiology clinicians to collaborate and innovate to advance the practice of pediatric preventive cardiology.

Familial Hypercholesterolemia Biomarker Distribution in Dried Blood Spots.

OBJECTIVE: To evaluate distribution profiles of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and apolipoprotein B (apoB) as candidate markers of familial hypercholesterolemia in newborns, taking into consideration potential confounding factors, such as gestational age, birth weight, sex, and race. STUDY DESIGN: TC, LDL-C, and apoB were measured from 10 000 residual deidentified newborn dried blood spot cards. Concentrations for each biomarker were reported as multiples of the median, with emphasis on describing the 99th percentile values based on birth weight, gestational age, sex, and race. Seasonal variation of biomarkers was also explored. RESULTS: LDL-C and apoB had distribution curves with tails showing extreme elevation, whereas the distribution of TC was less elevated and had the smallest range. Neonates born at early gestational age and low birth weight had significantly greater 99th percentile of multiples of the median values for apoB but not TC or LDL-C. Differences in biomarker concentration based on sex and race were minimal. All biomarkers showed greatest concentrations in the winter as compared with summer months. CONCLUSIONS: LDL-C and apoB had distribution curves supporting candidacy for neonatal familial hypercholesterolemia screening. Future studies are needed to correlate newborn screening results with molecular testing to validate these 2 biomarkers, along with measured cholesterol levels later in childhood.

Evolution of vertebral numbers in primates, with a focus on hominoids and the last common ancestor of hominins and panins.

The primate vertebral column has been extensively studied, with a particular focus on hominoid primates and the last common ancestor of humans and chimpanzees. The number of vertebrae in hominoids-up to and including the last common ancestor of humans and chimpanzees-is subject to considerable debate. However, few formal ancestral state reconstructions exist, and none include a broad sample of primates or account for the correlated evolution of the vertebral column. Here, we conduct an ancestral state reconstruction using a model of evolution that accounts for both homeotic (changes of one type of vertebra to another) and meristic (addition or loss of a vertebra) changes. Our results suggest that ancestral primates were characterized by 29 precaudal vertebrae, with the most common formula being seven cervical, 13 thoracic, six lumbar, and three sacral vertebrae. Extant hominoids evolved tail loss and a reduced lumbar column via sacralization (homeotic transition at the last lumbar vertebra). Our results also indicate that the ancestral hylobatid had seven cervical, 13 thoracic, five lumbar, and four sacral vertebrae, and the ancestral hominid had seven cervical, 13 thoracic, four lumbar, and five sacral vertebrae. The last common ancestor of humans and chimpanzees likely either retained this ancestral hominid formula or was characterized by an additional sacral vertebra, possibly acquired through a homeotic shift at the sacrococcygeal border. Our results support the 'short-back' model of hominin vertebral evolution, which postulates that hominins evolved from an ancestor with an African ape-like numerical composition of the vertebral column.

Parental Attitudes and Ideas Regarding Newborn Screening for Familial Hypercholesterolemia.

BACKGROUND: Familial hypercholesterolemia (FH) is an inherited disease which causes premature atherosclerotic cardiovascular disease. However, less than 10% of individuals with FH have been identified. OBJECTIVE: To assess parental perspectives for inclusion of FH on routine newborn screening (NBS) and to highlight potential benefits, harms, and ethical concerns. METHODS: Telephone interviews of two groups were conducted: 1) parents of children diagnosed with FH, and 2) parents of children diagnosed with a genetic condition through NBS. Stratified purposive sampling was used to ensure adequate representation. The 11 telephone interviews were conducted in 30-min sessions guided by a semi-structured interview script. At the beginning of the interview, participants were educated on the NBS process and FH. The interviews were transcribed verbatim, and a thematic analysis was performed in multiple steps. RESULTS: All interviewees indicated that they would be interested in having their child be screened for FH on the newborn screen. Reasons supporting screening during the newborn period included knowing their child's diagnosis, the ability to screen family members for FH, incorporation of lifestyle changes, and access to preventive care. Negatives surrounding screening during the newborn period included increased stress or anxiety, knowledge, stigma, and the delay from diagnosis to initiation of pharmacotherapy for FH. CONCLUSION: While these interviewees were in favor of NBS for FH, further education of parents and clinicians is needed to ensure proper implementation. The results of this study may be useful to formulate family notification and care protocols for newborns diagnosed with FH and other diseases.

What is already known on this subject? Familial hypercholesterolemia is a common inherited disorder that predisposes to early cardiovascular disease, but most affected individuals are not diagnosed. Childhood cholesterol screening is an effective but underutilized diagnostic tool. Previous studies report parents find childhood cholesterol screening acceptable, but it is not known if screening newborns would also be acceptable.What does this study add? Interviewees found screening newborns for familial hypercholesterolemia acceptable and would agree to screen their own newborn. The ability to screen other family members and access to early treatment were important factors in their decision to screen. Education of clinicians about familial hypercholesterolemia was an important concern raised by interviewees.

A Multidisciplinary Approach to Pediatric Obesity Shows Improvement Postintervention.

OBJECTIVE: Outpatient management of pediatric obesity can be difficult, requiring a significant time commitment from both provider and patient. Multidisciplinary clinic-based programs have shown promising effects in reducing BMI during intervention, but whether these changes are sustained over time is not well studied. The purpose of this study was to determine the post-treatment outcomes of children seen in a multidisciplinary pediatric obesity clinic (MPOC). METHODS: A retrospective chart review was performed using the MPOC database, which included all clinic patients from January 2008 to August 2016 who attended a minimum of 2 visits (n = 472). The primary outcome was the absolute change in BMI Z-score (BMIZ) from the final intervention visit compared to 1- and 2-years post-intervention. Multivariate regression analysis was performed to characterize predictors of change in BMIZ. RESULTS: MPOC patients ranged in age from 3 to 18 years. Mean BMIZ decreased significantly during intervention (-0.13 ± 1.47, P < .001) and was maintained at 1- and 2-years post-intervention. In participants ages 3 to 5, BMIZ further decreased at 1 year post intervention (-0.27 ± 0.26, P < .001). Age at time of referral was the only significant predictor of change in BMIZ. CONCLUSIONS: Outpatient, multidisciplinary intervention for pediatric obesity was effective in reducing or stabilizing BMIZ during and beyond the intervention, particularly when patients were referred at an early age. Although primary prevention is the ideal management, multidisciplinary clinic intervention can be effective in the sustained treatment of pediatric obesity.

Preventive Medicine in Pediatric Cardiology Practice.

OBJECTIVES: The objective of the study was to assess contemporary practice patterns of pediatric cardiologists with respect to cholesterol disorders and smoking-related illness. STUDY DESIGN: We sent 2 anonymous surveys to the members of the American Academy of Pediatrics Section on Cardiology and Cardiac Surgery and the Pediheart online community. The surveys addressed training in and management of cholesterol disorders and smoking-related illness. RESULTS: There were 97 responses to the cholesterol disorders survey. A total of 51.6% reported little or no formal training on cholesterol disorders. A total of 56.4% underestimated the prevalence of familial hypercholesterolemia by at least twofold. A total of 54.7% were at least somewhat comfortable prescribing statins. In 5 clinical vignettes, respondents frequently gave clinical recommendations in line with the 2019 American Heart Association guidelines although both undertreatment and overtreatment were recommended. There were 90 responses to the survey on smoking-related illness. Little or no formal training in nicotine addiction (52.3%) or smoking cessation (60.5%) was reported by respondents. Respondents screened for tobacco use in less than a one-third of hospitalizations and less than two-thirds of outpatient clinic visits. Screening for exposure to secondhand smoke was even less common. Twenty-seven percent of respondents never recommend a household smoking ban for their patients. A total of 83.3% were uncomfortable prescribing medications for their patients for smoking cessation, and 65.5% rarely or never refer patients for smoking cessation assistance. CONCLUSION: Although positioned to address the childhood origins of adult heart disease, those cardiologists surveyed placed a limited emphasis on cholesterol disorders and smoking-related disease in their clinical practice.

Screening and Management of Dyslipidemia in Children and Adolescents.

This review provides an overview of pediatric dyslipidemia emphasizing screening and treatment recommendations. The presence of risk factors for cardiovascular disease in childhood poses significant risk for the development of atherosclerotic cardiovascular disease and cardiovascular events in adulthood. While atherogenic dyslipidemia is the most common dyslipidemia seen in children and can be suspected based on the presence of risk factors (such as obesity), familial hypercholesterolemia can be found in children with no risk factors. As such, universal cholesterol screening is recommended to identify children with these disorders in order to initiate treatment and reduce the risk of future cardiovascular disease. Treatment of pediatric dyslipidemia begins with lifestyle modifications, but primary genetic dyslipidemias may require medications such as statins. As pediatric lipid disorders often have genetic or familial components, it is important that all physicians are aware that cardiovascular risk begins in childhood, and can both identify these disorders in pediatric patients and counsel their adult patients with dyslipidemia to have their children screened.

Nutrition interventions for youth with dyslipidemia: a National Lipid Association clinical perspective.

A heart-healthy lifestyle, beginning at an early age and sustained throughout life, may reduce risk for cardiovascular disease in youth. Among youth with moderate to severe dyslipidemia and/or those with familial hypercholesterolemia, lipid-lowering medications are often needed for primary prevention of cardiovascular disease. However, lifestyle interventions are a foundation for youth with dyslipidemia, as well as those without dyslipidemia. There are limited data supporting the use of dietary supplements in youth with dyslipidemia at this time. A family-centered approach and the support of a multi-disciplinary healthcare team, which includes a registered dietitian nutritionist to provide nutrition counseling, provides the best opportunity for primary prevention and improved outcomes. While there are numerous guidelines that address the general nutritional needs of youth, few address the unique needs of those with dyslipidemia. The goal of this National Lipid Association Clinical Perspective is to provide guidance for healthcare professionals caring for youth with disorders of lipid and lipoprotein metabolism, including nutritional guidance that complements the use of lipid lowering medications.

Impact of the COVID-19 pandemic on cardiometabolic health parameters in children with preexisting dyslipidemia.

BACKGROUND: The COVID-19 pandemic has raised concerns for worsening cardiometabolic health in children. OBJECTIVE: This study evaluates the impact of the COVID-19 pandemic and subsequent social restrictions on pediatric cardiometabolic health factors. METHODS: Retrospective review of patients in a pediatric lipid clinic in the year prior to (3/18/2019-3/17/2020) and during (3/18/2020-3/17/2021) the COVID-19 pandemic was performed. Physical findings (body mass index [BMI], waist circumference [WC], and blood pressure), laboratory markers of cardiometabolic health (lipid panel, insulin resistance, and liver transaminases), self-reported exercise time, and lipid-lowering medications (metformin, statin, omega-3 fatty acids, fenofibrate) were compared. RESULTS: 297 subjects met inclusion criteria. Among subjects prescribed no medications or on stable medication doses (n=241), there were few changes in lipid panels. Among subjects with new or increased medication doses between pre-pandemic and pandemic intervals (n=62), there were increases in triglycerides (p= 0.019) and HgbA1c (p=0.046). There was no change in z-scores for both BMI and WC for either group. CONCLUSION: We observed concerning trends in markers of cardiovascular disease health (dyslipidemia, insulin resistance, and diabetes), independent of changes in weight, in at-risk children during the recent COVID pandemic. Our findings suggest that this vulnerable population may benefit from more frequent monitoring and intense management during such events.

Low HDL-C is a non-fasting marker of insulin resistance in children.

OBJECTIVES: Childhood obesity and associated comorbidities, including insulin resistance, are increasing in the United States. Our objectives were to (1) determine the prevalence of insulin resistance in children seen in dyslipidemia clinic and (2) evaluate which aspects of the lipid profile correlate with insulin resistance. METHODS: Children and adolescents seen in a specialized pediatric dyslipidemia clinic without secondary diagnoses known to alter the lipid panel were included. Simultaneous fasting lipid panel, insulin, and glucose levels were available in 572 children (50.5% male). RESULTS: Mean patient age was 15.0 ± 3.6 years with the majority being over 10 years of age (92.5%). Mean BMI was 29.8 ± 8.1 kg/m2 and BMI standard deviation score was 1.80 ± 0.9. Mean HOMA-IR was 6.2 ± 5.7 with a range of 0.4-49.3, and interquartile range of 2.7-7.6. Triglyceride level had a positive correlation with HOMA-IR (p<0.001). HDL-C negatively correlated with HOMA-IR even controlling for triglyceride level by multivariate analysis (p=0.001) and HDL-C <30 mg/dL predicted IR with 41.5% PPV. CONCLUSIONS: In children and adolescents with dyslipidemia, insulin resistance is common and significantly correlates with reduced HDL-C levels. Non-fasting samples are easier to obtain in children and low HDL-C, which is minimally affected on non-fasting samples, could be an easily obtained indicator of IR. Increasing detection of insulin resistance in children with dyslipidemia may provide greater opportunities for lifestyle interventions and possible pharmacotherapy to modify cardiovascular risk.

Rationale and design of two trials assessing the efficacy, safety, and tolerability of inclisiran in adolescents with homozygous and heterozygous familial hypercholesterolaemia.

BACKGROUND: Inclisiran is a small interfering RNA molecule that reduces low-density lipoprotein cholesterol (LDL-C) by inhibition of proprotein convertase subtilisin/kexin type 9. This subcutaneous, twice-yearly administered agent has been shown to effectively and safely lower LDL-C in adult patients with established atherosclerotic cardiovascular disease, adults at high risk for atherosclerotic cardiovascular disease, as well as in adults with heterozygous familial hypercholesterolaemia. With the current, limited treatment options available to reach treatment goals in children with severe heterozygous familial hypercholesterolaemia, homozygous familial hypercholesterolaemia, or statin intolerance, inclisiran could be a valuable new therapeutic option. OBJECTIVES: The objective of these ongoing studies is to investigate the efficacy, safety, and tolerability of inclisiran in adolescents diagnosed with homozygous familial hypercholesterolaemia (ORION-13) or heterozygous familial hypercholesterolaemia (ORION-16). STUDY DESIGN: ORION-13 and ORION-16 are both two-part (1-year double-blind inclisiran vs. placebo/1 year open-label inclisiran) multicentre trials including adolescents aged 12 to <18 years diagnosed with familial hypercholesterolaemia. ORION-13 will include ∼12 participants diagnosed with homozygous familial hypercholesterolaemia and ORION-16 will include ∼150 participants diagnosed with heterozygous familial hypercholesteroleamia. The primary endpoint is the percentage change in LDL-C from baseline to Day 330. Secondary efficacy and safety endpoints include changes in other lipid parameters and treatment-emergent adverse events as well as laboratory parameters and vital signs. Exploratory endpoints include individual responsiveness of the participants and change in LDL-C according to the type of underlying causal mutation. CLINICAL TRIAL REGISTRATION: https://www.clinicaltrials.gov/. Unique identifier: NCT04659863 (ORION-13) and NCT04652726 (ORION-16).

Prevention of Atherosclerotic Cardiovascular Disease in Children with Familial Hypercholesterolemia.

PURPOSE OF REVIEW: Familial hypercholesterolemia (FH), a common inherited disorder of LDL-C metabolism that predisposes to premature cardiovascular disease, is underdiagnosed. Despite recommendations for screening all children and initiation of lipid-lowering medication beginning at 8-10 years of age, adherence to guidelines is low. Most individuals with FH are inadequately treated, especially women and children. The purpose of this review is to discuss current literature and recommendations for the diagnosis and treatment of heterozygous FH (HeFH) in the pediatric population. RECENT FINDINGS: Twenty-year outcome data demonstrate lower rates of atherosclerotic cardiovascular disease (ASCVD) related events and death in individuals with FH who were treated with statins from childhood, compared to those who initiated statins in adulthood. While diagnosis rates of FH are slowly improving, most clinicians do not adhere to recommendations for cholesterol screening in youth. Identifying youth with FH offers the opportunity for early intervention to prevent ASCVD and identify affected relatives through reverse cascade screening.

Differences in pediatric cholesterol screening rates between family physicians and pediatricians correlate with conflicting guidelines.

Conflicting guidelines regarding universal pediatric cholesterol screening were released between 2011 and 2019, but the impact on screening rates remains understudied. The purpose of this study was to examine trends in pediatric cholesterol screening rates within a single institution in the United States and their association with release of national guidelines, local educational tools, and electronic health record (EHR) modifications. Order placement was defined as ordering a high-density lipoprotein cholesterol level in a patient aged 9-21 years with ≥1 well visit in prior 3 years. Order placement rate (OPR) was calculated per month using 3 months' moving average smoothing and analyzed based on date, patient age, and specialty of ordering clinician. Timing of educational tools, EHR modifications, and national guideline release were analyzed for changes in OPR. Prior to release of 2011 guidelines recommending universal pediatric cholesterol screening, pediatrician OPR was 35% (95% CI: 29-43%) compared to 8% (7-11%) for family physicians. For both specialties, OPR increased after 2011 guidelines, educational initiatives, and EHR changes, but decreased after 2016, with a larger decrease for family physicians (p < 0.001 for all). OPR was consistently higher for pediatricians than for family physicians during the study period, with largest OPR changes correlating with release of guidelines. The findings from the study suggest that conflicting guidelines may contribute to lower overall OPR, and to different screening rates for children cared for by pediatricians compared to family physicians.

Cascade Screening and Treatment Initiation in Young Adults with Heterozygous Familial Hypercholesterolemia.

Heterozygous familial hypercholesterolemia (HeFH) creates elevated low-density lipoprotein cholesterol (LDL-C), causing premature atherosclerotic cardiovascular disease (ASCVD). Guidelines recommend cascade screening relatives and starting statin therapy at 8-10 years old, but adherence to these recommendations is low. Our purpose was to measure self-reported physician practices for cascade screening and treatment initiation for HeFH using a survey of 500 primary care physicians and 500 cardiologists: 54% "always" cascade screen relatives of an individual with FH, but 68% would screen individuals with "strong family history of high cholesterol or premature ASCVD", and 74% would screen a child of a patient with HeFH. The most likely age respondents would start statins was 18-29 years, with few willing to prescribe to a pediatric male (17%) or female (14%). Physicians who reported previously diagnosing a patient with HeFH were more likely to prescribe to a pediatric patient with HeFH, either male (OR = 1.34, 95% CI = 0.99-1.81) or female (OR = 1.31, 95% CI = 0.99-1.72). Many physicians do not cascade screen and are less likely to screen individuals with family history of known HeFH compared to "high cholesterol or premature ASCVD". Most expressed willingness to screen pediatric patients, but few would start treatment at recommended ages. Further education is needed to improve diagnosis and treatment of HeFH.

Perceptions and Barriers on the Use of Proprotein Subtilisin/Kexin Type 9 Inhibitors in Heterozygous Familial Hypercholesterolemia (From a Survey of Primary Care Physicians and Cardiologists).

Heterozygous familial hypercholesterolemia (HeFH) results in significant elevations in LDL-C and premature atherosclerotic cardiovascular disease (ASCVD). Current guidelines recommend add-on proprotein subtilisin/kexin type 9 inhibitor (PCSK9i) therapy for additional LDL-C lowering beyond statins. Data are sparse, however, regarding treatment patterns and barriers relating to PCSK9i in HeFH patients. We examined physician attitudes, use, and barriers for treatment in patients with HeFH. We surveyed 1,000 physicians (500 primary care providers [PCPs] and 500 cardiologists in the US regarding their preferred treatments, experience and barriers associated with using PCSK9is. Cardiologists compared to PCPs were more likely to rank a PCSK9i as most important for an HeFH patient needing additional LDL-C lowering (68.6% vs. 64.8%; p <0.05), as well as prescribing and having a patient on a PCSK9i. PCPs vs. cardiologists were less likely (odds ratio [OR] [95% confidence interval] = 0.46 [0.34-0.63]), private vs. academic practice more likely (OR = 1.53 [1.02-2.28]), and those who would prescribe a PCSK9i in an HeFH patient with (OR = 3.86 [2.57-5.78]) or without (OR = 1.96 [1.40-2.72]) ASCVD needing additional LDL-C reduction beyond a statin were more likely to actually prescribe a PCSK9i. Those practicing in an urban vs. rural setting were less likely (OR = 0.56 [0.34-0.93]), and those indicating they would prescribe a PCKS9i in an HeFH patient with (OR = 2.80 [1.74-4.49]) or without (OR = 1.43 [1.02-2.02]) ASCVD needing additional LDL-C lowering beyond a statin were more likely to face difficulty prescribing a PCSK9i (all p <0.05 to p <0.01). Greater physician education and assistance among both cardiologists and PCPs are needed to address the gaps in understanding and treatment regarding PCSK9is.

Children with Heterozygous Familial Hypercholesterolemia in the United States: Data from the Cascade Screening for Awareness and Detection-FH Registry.

OBJECTIVE: To describe enrollment characteristics of youth in the Cascade Screening for Awareness and Detection of FH Registry. STUDY DESIGN: This is a cross-sectional analysis of 493 participants aged <18 years with heterozygous familial hypercholesterolemia recruited from US lipid clinics (n = 20) between April 1, 2014, and January 12, 2018. At enrollment, some were new patients and some were already in care. Clinical characteristics are described, including lipid levels and lipid-lowering treatments. RESULTS: Mean age at diagnosis was 9.4 (4.0) years; 47% female, 68% white and 12% Hispanic. Average (SD) highest Low-density lipoprotein cholesterol (LDL-C) was 238 (61) mg/dL before treatment. Lipid-lowering therapy was used by 64% of participants; 56% were treated with statin. LDL-C declined 84 mg/dL (33%) among those treated with lipid-lowering therapy; statins produced the greatest decline, 100 mg/dL (39% reduction). At enrollment, 39% had reached an LDL-C goal, either <130 mg/dL or ≥50% decrease from pre-treatment; 20% of those on lipid-lowering therapy reached both goals. CONCLUSIONS: Among youth enrolled in the Cascade Screening for Awareness and Detection of FH Registry, diagnosis occurred relatively late, only 77% of children eligible for lipid-lowering therapy were receiving treatment, and only 39% of those treated met their LDL-C goal. Opportunities exist for earlier diagnosis, broader use of lipid-lowering therapy, and greater reduction of LDL-C levels.

Phenotypic Variability in Atherosclerosis Burden in an Old-Order Amish Family With Homozygous Sitosterolemia.

Sitosterolemia is a rare atherogenic sterol storage disease with variability in its presentation requiring a high degree of clinical suspicion. We present 8 cases of sitosterolemia from an Amish kindred that, despite a background of decreased genetic and lifestyle variability, still had markedly variable presentations. (Level of Difficulty: Advanced.).