Low LDL-C: Is It all Good News?

PURPOSE OF REVIEW: This review presents the risks and benefits of very low LDL cholesterol and the safety of using lipid-lowering therapy to achieve these levels. RECENT FINDINGS: A growing body of literature suggests that lower LDL cholesterol levels are associated with a reduced risk of cardiovascular disease. Further, achieving these levels with pharmaceuticals is remarkably safe. Although statins may slightly increase the risk of diabetes mellitus and hemorrhagic stroke, the benefits outweigh the risks. While recommendations from professional societies are increasingly aggressive, additional risk reduction could be achieved by setting more even ambitious LDL cholesterol goals.

Clinical practice recommendations on lipoprotein apheresis for children with homozygous familial hypercholesterolaemia: An expert consensus statement from ERKNet and ESPN.

Homozygous familial hypercholesterolaemia is a life-threatening genetic condition, which causes extremely elevated LDL-C levels and atherosclerotic cardiovascular disease very early in life. It is vital to start effective lipid-lowering treatment from diagnosis onwards. Even with dietary and current multimodal pharmaceutical lipid-lowering therapies, LDL-C treatment goals cannot be achieved in many children. Lipoprotein apheresis is an extracorporeal lipid-lowering treatment, which is used for decades, lowering serum LDL-C levels by more than 70% directly after the treatment. Data on the use of lipoprotein apheresis in children with homozygous familial hypercholesterolaemia mainly consists of case-reports and case-series, precluding strong evidence-based guidelines. We present a consensus statement on lipoprotein apheresis in children based on the current available evidence and opinions from experts in lipoprotein apheresis from over the world. It comprises practical statements regarding the indication, methods, treatment goals and follow-up of lipoprotein apheresis in children with homozygous familial hypercholesterolaemia and on the role of lipoprotein(a) and liver transplantation.

Evinacumab for Pediatric Patients With Homozygous Familial Hypercholesterolemia.

BACKGROUND: Homozygous familial hypercholesterolemia (HoFH) is a rare genetic disorder characterized by severely elevated low-density lipoprotein cholesterol (LDL-C) levels due to profoundly defective LDL receptor (LDLR) function. Given that severely elevated LDL-C starts in utero, atherosclerosis often presents during childhood or adolescence, creating a largely unmet need for aggressive LDLR-independent lipid-lowering therapies in young patients with HoFH. Here we present the first evaluation of the efficacy and safety of evinacumab, a novel LDLR-independent lipid-lowering therapy, in pediatric patients with HoFH from parts A and B of a 3-part study. METHODS: The phase 3, part B, open-label study treated 14 patients 5 to 11 years of age with genetically proven HoFH (true homozygotes and compound heterozygotes) with LDL-C >130 mg/dL, despite optimized lipid-lowering therapy (including LDLR-independent apheresis and lomitapide), with intravenous evinacumab 15 mg/kg every 4 weeks. RESULTS: Evinacumab treatment rapidly and durably (through week 24) decreased LDL-C with profound reduction in the first week, with a mean (SE) LDL-C reduction of -48.3% (10.4%) from baseline to week 24. ApoB (mean [SE], -41.3% [9.0%]), non-high-density lipoprotein cholesterol (-48.9% [9.8%]), and total cholesterol (-49.1% [8.1%]) were similarly decreased. Treatment-emergent adverse events were reported in 10 (71.4%) patients; however, only 2 (14.3%) reported events that were considered to be treatment-related (nausea and abdominal pain). One serious treatment-emergent adverse event of tonsillitis occurred (n=1), but this was not considered treatment-related. CONCLUSIONS: Evinacumab constitutes a new treatment for pediatric patients with HoFH and inadequately controlled LDL-C despite optimized lipid-lowering therapy, lowering LDL-C levels by nearly half in these extremely high-risk and difficult-to-treat individuals. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04233918.

Clinical practice recommendations on lipoprotein apheresis for children with homozygous familial hypercholesterolemia: an expert consensus statement from ERKNet and ESPN.

Homozygous familial hypercholesterolaemia is a life-threatening genetic condition, which causes extremely elevated LDL-C levels and atherosclerotic cardiovascular disease very early in life. It is vital to start effective lipid-lowering treatment from diagnosis onwards. Even with dietary and current multimodal pharmaceutical lipid-lowering therapies, LDL-C treatment goals cannot be achieved in many children. Lipoprotein apheresis is an extracorporeal lipid-lowering treatment, which is well established since three decades, lowering serum LDL-C levels by more than 70% per session. Data on the use of lipoprotein apheresis in children with homozygous familial hypercholesterolaemia mainly consists of case-reports and case-series, precluding strong evidence-based guidelines. We present a consensus statement on lipoprotein apheresis in children based on the current available evidence and opinions from experts in lipoprotein apheresis from over the world. It comprises practical statements regarding the indication, methods, treatment targets and follow-up of lipoprotein apheresis in children with homozygous familial hypercholesterolaemia and on the role of lipoprotein(a) and liver transplantation.

Decreasing Sedentary Behaviors in Youth to Prevent and Manage Childhood Obesity: Is It Realistic?

PURPOSE OF REVIEW: Decreasing sedentary behaviors has been proposed as one approach to reduce the rate of obesity in youth. This review summarizes the contemporary literature examining the efficacy of these interventions in the school and community along with an additional focus on the role of socioeconomic status in these interventions. RECENT FINDINGS: Studies that focus on decreasing sedentary behavior have utilized a wide variety of strategies in a number of settings. The effects of these interventions are often hindered by non-standard outcome measures, study infidelity, and subjective measures of sedentary time. However, interventions that incorporate engaged stakeholders and include younger subjects appear to be the most likely to succeed. Promising interventions to decrease sedentary behaviors have been shown in recent clinical trials; however, replicating and sustaining these results is challenging. From the available literature, school-based interventions have the potential of reaching the largest group of children. In contrast, interventions in younger children, particularly those with invested parents, seem to be the most effective.

The association of objectively measured sedentary time with asthma in US youth: A glimpse into the connection between obesity and asthma.

BACKGROUND: Evidence suggests that asthma and obesity may share a common pathway, possibly through an increase in inflammation. Sedentary time is thought to promote both inflammation and obesity and previous studies have found a relationship between self-reported sedentary and asthma. However, the relationship between objectively measured sedentary time and asthma is not well described. We hypothesized that the association between asthma and sedentary time would not be present when physical activity was measured objectively, nor would objectively-measured sedentary time play an important role in the relationship between asthma and obesity. OBJECTIVE: To determine if there is an association between asthma and objectively measured sedentary time in a large, nationally representative sample of the United States youth. METHODS: Using the National Health and Nutrition Examination Survey 2003-2006, we assessed the relationship between asthma and sedentary time using objectively measured and self-reported measures of sedentary time, in 6-19 years-old subjects with available accelerometry data. We used multivariate logistic regression analysis to determine associations between the risk of asthma and sedentary time controlling for accelerometer wear time, gender, age, race/ethnicity, body mass index percentile, and moderate-to-vigorous physical activity (MVPA). RESULTS: In this cohort, youth with asthma self-reported more time in sedentary behavior, specifically computer time, than those without asthma (p = 0.01). However, when sedentary time was measured objectively by accelerometry, sedentary time did not differ between youth with and without asthma (421 min [standard deviation 4.2] versus. 414 min [standard deviation 7.8] [p = 0.38]). Controlling for measures of activity, such as MVPA, or time spent in long versus short bouts of sedentary time did not modify our results. CONCLUSIONS: Differences in sedentary time by self-report between those with and without asthma were not born out by examining sedentary time using objective measures. Further work is necessary to examine the complex interaction among inactivity, obesity, and asthma over time, specifically focusing on whether the type of sedentary activity (e.g., computer vs. television time) is important.

Adherence to lipid-lowering therapy and reaching treatment goals in youth seen in a preventive cardiology clinic.

INTRODUCTION: The efficacy of lipid-lowering therapy in reducing cardiovascular disease in adults is well-established. Unfortunately, it is also well-established that adults have inadequate adherence to lipid-lowering therapy, which is associated with increased costs and mortality. However, the adherence patterns of youth prescribed lipid-lowering therapy is not well-described. METHODS: We analyzed data that was prospectively collected from patients <27 years-old who were referred to a large regional preventive cardiology clinic from 2010 to 2017. Adherence to lipid-lowering therapy was self-reported at the patient's most recent clinic visit and categorized as either adequate adherence (≥80%) or inadequate adherence (<80%). We compared adherence rates by demographic factors, class of lipid-lowering therapy, length of time on lipid-lowering therapy, family history, lipid parameters, and laboratory measures of adverse effects. RESULTS: In our cohort, we had 318 patients prescribed a lipid-lowering medication over a seven-year period. Of those, 235 (75%) had adequate adherence. Those with adequate adherence had an improved LDL-C (123 mg/dL [standard deviation (SD) 32.3] vs. 167 mg/dL [SD 50.4], p < 0.05), total cholesterol (198 mg/dL [49.5] vs. 239 mg/dL [SD 53.2]), and non-HDL-C (148 mg/dL [SD 38.7] vs. 193 mg/dL [SD 43.9]). In addition, patients with adequate adherence were more likely to reach goal LDL-C of <130 mg/dL than those with inadequate adherence (130 vs. 25, p < 0.01). The relationship between LDL-C and adherence remained statistically significant after controlling for age, gender, and the length of time on therapy (ß = -0.66, p < 0.01). Adherence level did not differ by gender, class of lipid-lowering therapy, length of time on lipid-lowering therapy, or presence of a family history of an atherosclerotic event. The findings were similar when we only analyzed those prescribed a statin. CONCLUSIONS: Self-reported adherence to lipid-lowering therapy in youth is excellent and was associated with achieving goal LDL-C goals. Obtaining adherence data from patients may help more patients reach LDL-C goals.

Clinical response to lifestyle counseling for dyslipidemia and elevated blood pressure in childhood cancer survivors.

BACKGROUND: Childhood cancer survivors (CCS) have increased risk of premature cardiovascular disease. Whether they respond similarly to lifestyle changes for elevated blood pressure (BP), body mass index (BMI), and dyslipidemia to those without history of childhood cancer is unknown. PROCEDURE: This retrospective cohort study included CCS and 3:1 age- and sex-matched controls treated at Boston Children's Hospital Preventive Cardiology (2010-2019) using lifestyle management based on National Heart, Lung, and Blood Institute (NHLBI) guidelines. Change in BMI, BP, and lipids were analyzed. RESULTS: We included 52 CCS and 162 controls with a median age of approximately 16 years. More CCS (84.3%) had elevated baseline fasting triglycerides (TG) than controls (49.4%) (p < .001). More CCS (62.5%) also had abnormal baseline high-density lipoprotein cholesterol (HDL-C) compared to controls (35.2%) (p = .001). Baseline BMI, BP, total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) were similar between groups. Over 15 weeks [IQR: 10.5-26], CCS had greater decrease in TG than controls (72.5 vs. 17 mg/dl decrease, p = .095). BP improved in 5% of CCS versus 38% of controls (p = .008). For both, BMI, TC, LDL-C, and HDL-C remained stable. CCS with stem cell transplantation (SCT) had a TC increase of 5% (6 mg/dl) compared to a decrease of 9% (19 mg/dl) among CCS without SCT (p = .02). CONCLUSIONS: CCS demonstrated similar improvement in lipids, but impaired BP lowering in response to lifestyle management compared to controls. Further prospective studies are needed to determine if earlier pharmaceutical treatment is warranted in this higher risk population and for the long-term risk reductions of these approaches.

Isometric Exercise Increases the Diameter of the Ascending Aorta in Youth with Bicuspid Aortic Valves.

Central arterial pressure rises to much higher levels during heavy isometric exercise compared to other forms of exercise. For this reason, patients with bicuspid aortic valves (BAV) are often restricted from heavy isometric exercise. Although this approach may be theoretically appealing, no data exist regarding the efficacy of this activity restriction.Patients between 12 and 21 years old with isolated BAV were enrolled if they had a previous echocardiogram at least 2 years prior to the current clinic visit. Patients were excluded if they had additional congenital heart disease, a diagnosed syndrome, or had undergone a procedure involving the aortic valve or ascending aorta. Patients completed a questionnaire regarding frequency and intensity of isometric exercise during the 3-month period prior to the visit. We compared aortic dimensions (Z-score), aortic stenosis, and aortic insufficiency between an echocardiogram performed as part of the current visit and one obtained 2-5 years previously using paired t tests and multivariable regression controlling for age, gender, degree of aortic stenosis, and the presence of isometric exercise. In this sample of 50 adolescents with isolated bicuspid aortic valve, 30 (60%) subjects did not participate in any isometric exercise. Over an average of 2.9 years (SD 0.9 years), we did not find a significant difference between changes in the Z-score diameters of the aortic root (0.9 vs 0.9, p = 0.913) and ascending aorta Z-score (2.9 vs 2.9, p = 0.757), between subjects engaging and not engaging in isometric exercise. Further, we did not find that changes in valve function (i.e., aortic stenosis and aortic insufficiency) differed between the two groups.In this sample of adolescents with isolated bicuspid aortic valve, there was no medium-term increase in aortic dilation or worsening valve function in those who engaged in isometric exercise versus those who refrained from isometric exercise.

Surgical Repair of Congenital Atresia of the Left Coronary Ostium.

Congenital left main coronary artery atresia is an exceedingly rare condition with potentially fatal consequences if not diagnosed in a timely fashion. We present a case series in children and adolescents, including surgical repair and outcomes. We describe the presenting symptoms and subsequent management of each patient, including surgical repair and outcomes. (Level of Difficulty: Advanced.).

Improving Cardiovascular Health in a Pediatric Preventive Cardiology Practice.

Poor childhood cardiovascular health translates into poor adult cardiovascular health. We hypothesized care in a preventive cardiology clinic would improve cardiovascular health after lifestyle counseling. Over a median of 3.9 months, mean cardiovascular health score (range 0-11) improved from 5.8 ± 2.2 to 6.3 ± 2.1 (P < .001) in 767 children.

Cardiorespiratory Fitness in Youth: An Important Marker of Health: A Scientific Statement From the American Heart Association.

Cardiorespiratory fitness (CRF) refers to the capacity of the circulatory and respiratory systems to supply oxygen to skeletal muscle mitochondria for energy production needed during physical activity. CRF is an important marker of physical and mental health and academic achievement in youth. However, only 40% of US youth are currently believed to have healthy CRF. In this statement, we review the physiological principles that determine CRF, the tools that are available to assess CRF, the modifiable and nonmodifiable factors influencing CRF, the association of CRF with markers of health in otherwise healthy youth, and the temporal trends in CRF both in the United States and internationally. Development of a cost-effective CRF measurement process that could readily be incorporated into office visits and in field settings to screen all youth periodically could help identify those at increased risk.

Lipoprotein Particle Predictors of Arterial Stiffness after 17 Years of Follow Up: The Malmö Diet and Cancer Study.

BACKGROUND: Central arterial stiffness is a surrogate of cardiovascular risk and predicts cardiovascular mortality. Apolipoprotein B lipoproteins are also established cardiovascular risk factors. It is not known whether specific lipoprotein subclasses measured in the Malmö Diet and Cancer Study and previously shown to be associated with coronary heart disease also predict arterial stiffening after a mean period of 17 years. METHODS: Lipoprotein particle analysis was performed on 2,505 men and women from Malmö, Sweden, from 1991 to 1994, and arterial stiffness was assessed by carotid-femoral pulse wave velocity (c-fPWV) on this same cohort from 2007 to 2012. Associations between c-fPWV and lipoprotein particles were determined with multiple linear regression, controlling for sex, presence of diabetes, waist-to-hip circumference, and smoking status at baseline, as well as heart rate (measured at the carotid artery), mean arterial pressure, antihypertensive and lipid-lowering medications, C-reactive protein (CRP), and age at the time of c-fPWV measurement. RESULTS: The results confirm that triglycerides (TG) and high-density lipoprotein cholesterol (HDL-c) but not low-density lipoprotein cholesterol (LDL-c) predict c-fPWV. We identify a positive predictive association for very small, small, and medium (high risk), but not large LDL particles. There was a negative association for large HDL particles. The relationships between c-fPWV and high-risk LDL particles were unaffected by adjusting for LDL-c or CRP and were only mildly attenuated by adjusting for the homeostatic model for insulin resistance (HOMA-IR). Due to the collinearity of very small, small, and medium LDL particles and dyslipidemia (elevated TG and decreased HDL-c), the observed relationship between c-fPWV and high-risk LDL particles became insignificant after controlling for the concentration of HDL-c, large cholesterol-rich HDL particles, and TG. CONCLUSIONS: The development of central arterial stiffness previously associated with combined dyslipidemia may be mediated in part by LDL particles, particularly the very small-, small-, and medium-sized LDL particles.

The relationship between payer type and lipid outcomes in response to clinical lifestyle interventions in youth with dyslipidemia.

BACKGROUND: Payer-type (government-sponsored health coverage versus private health insurance) has been shown to influence a variety of cardiovascular disease outcomes in adults. However, it is unclear if the payer-type impacts the response to a lifestyle intervention in children with dyslipidemia. METHODS: We analyzed data prospectively collected from patients under the age of 25 years who were referred to a large regional preventive cardiology clinic from 2010 to 2016 in Massachusetts. We compared baseline high density lipoprotein cholesterol (HDL-C), triglycerides (TG), non-HDL-C, and low density lipoprotein cholesterol (LDL-C) by payer-type. Further, we analyzed the change in lipid values in response to a clinic-based multidisciplinary intervention over a nearly six-year period by payer-type with multi-variable adjusted linear regression models. We also tested for effect modifications by age, sex, race, and body mass index (BMI) category. RESULTS: Of the 1739 eligible patients (mean age 13 years, 52% female, 60% overweight and obese, 59% White), we found that patients with government-sponsored coverage (n = 354, 20%) presented to referral lipid clinic with lower HDL-C (- 3.5 mg/dL [1.0], p < 0.001) and higher natural log-transformed TG (+ 0.14 [0.04], p < 0.001) as compared to those with private insurance; however, the association was attenuated to the null after additionally adjusting for BMI category (- 1.1 [0.9], p = 0.13, and + 0.05 [0.04], p = 0.2 for HDL-C and natural log-transformed TG, respectively). We found no difference in baseline LDL-C between payer-types (+ 3.4 mg/dL [3.0], p = 0.3). However, longitudinally, we found patients with private insurance and a self-reported race of White to have a clinically meaningful additional improvement in LDL-C, decreasing 12.8 (5.5) mg/dL (p = 0.02) between baseline and first follow-up, as compared to White patients with government-sponsored health coverage, after adjusting for age, sex, time between visits, and baseline LDL-C. CONCLUSIONS: Our results suggest that youth with government-sponsored coverage are referred with poorer lipid profiles than those with private insurance, although this is largely explained by higher rates of overweight and obesity in the government-sponsored health coverage group. White patients with private insurance had substantially better improvement in LDL-C longitudinally, suggesting that higher socioeconomic status facilitates improvement in LDL-C, but is less beneficial for HDL-C and triglyceride levels.

Hypertriglyceridemia in Diabetes Mellitus: Implications for Pediatric Care.

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). It is estimated that the risk of CVD in diabetes mellitus (DM) is 2 to 10 times higher than in the general population. Much of this increased risk is thought to be related to the development of an atherogenic lipid profile, in which hypertriglyceridemia is an essential component. Recent studies suggest that dyslipidemia may be present in children and adolescents with DM, particularly in T2DM and in association with poor control in T1DM. However, the role of hypertriglyceridemia in the development of future CVD in youth with DM is unclear, as data are scarce. In this review, we will evaluate the pathophysiology of atherogenic hypertriglyceridemia in DM, the evidence regarding an independent role of triglycerides in the development of CVD, and the treatment of hypertriglyceridemia in patients with DM, highlighting the potential relevance to children and the need for more data in children and adolescents to guide clinical practice.

Clustering of Health Behaviors and Cardiorespiratory Fitness Among U.S. Adolescents.

PURPOSE: Decreased cardiorespiratory fitness (CRF) is associated with an increased risk of cardiovascular disease. However, little is known how the interaction of diet, physical activity (PA), and sedentary time (ST) affects CRF among adolescents. By using a nationally representative sample of U.S. adolescents, we used cluster analysis to investigate the interactions of these behaviors with CRF. We hypothesized that distinct clustering patterns exist and that less healthy clusters are associated with lower CRF. METHODS: We used 2003-2004 National Health and Nutrition Examination Survey data for persons aged 12-19 years (N = 1,225). PA and ST were measured objectively by an accelerometer, and the American Heart Association Healthy Diet Score quantified diet quality. Maximal oxygen consumption (V˙O2​max) was measured by submaximal treadmill exercise test. We performed cluster analysis to identify sex-specific clustering of diet, PA, and ST. Adjusting for accelerometer wear time, age, body mass index, race/ethnicity, and the poverty-to-income ratio, we performed sex-stratified linear regression analysis to evaluate the association of cluster with V˙O2​max. RESULTS: Three clusters were identified for girls and boys. For girls, there was no difference across clusters for age (p = .1), weight (p = .3), and BMI (p = .5), and no relationship between clusters and V˙O2​max. For boys, the youngest cluster (p < .01) had three healthy behaviors, weighed less, and was associated with a higher V˙O2​max compared with the two older clusters. CONCLUSIONS: We observed clustering of diet, PA, and ST in U.S. adolescents. Specific patterns were associated with lower V˙O2​max for boys, suggesting that our clusters may help identify adolescent boys most in need of interventions.