2018-19 TOW #23: Lipid screening

The topic of lipid screening and dyslipidemia treatment remains a controversial one in pediatrics! It depends on whether you are in the camp of not missing anyone who meets potential criteria for intervention vs emphasizing the potential harms of overtesting and overtreating: the age-old epidemiologic debate, not to mention a value-based care question. Nationally, variation in recommendations reflects this debate: the AAP has sided with universal screening, while others, including the US Preventive Services Task Force and the AAFP find insufficient evidence to recommend screening before age 20. Dr. Perri Klass summarized the debate in her NYT blog, quoting Dr. Fred Rivara, MD MPH about his statement against universal screening. The goal this week is to be familiar with some of the recs and the evidence to inform your understanding and decision-making.

Materials for this week:

Take-home points:

  1. Who should be recommended for lipid testing? It depends on if you follow targeted screening vs universal screening, or if you believe in no benefit of screening in childhood. The 2011 NHLBI guidelines recommend targeted screening for children 2-8 years old and adolescents 12-16 years old and universal screening for children 9-11 years old and adolescents 17-21 years old. The repeat is done at age 17-21 to assess after puberty which can alter levels. These same recommendations are endorsed by the AAP. In the targeted approach, screening is indicated in children or adolescents with a positive family history of dyslipidemia or premature cardiovascular disease (CVD) (including parent or 2nd degree relative <55 male, <65 female), an unknown family history, or children with other risk factors for CVD, like obesity, hypertension and diabetes.
  2. If you are screening, what tests would you do? In the NHLBI guidelines, the recommendation for universal screening was to use non-fasting lipids and calculate the non-HDL-C as follows: Non-HDL-C = total cholesterol (TC) – HDL-C. If the non-HDL-C was >=145, then do follow-up with fasting lipid panel. For targeted screening, the rec was getting an average of 2 sets of fasting lipid profiles (FLP) separated by 2 weeks to 3 months (as the individual levels can vary by up to 30mg/dl). Triglycerides (TG) are much more likely to be overestimated with non-fasting draw, but total and non-HDL levels are considered more reliable when non-fasting. All of this seems much more complicated, and in practice, most pediatricians may only obtain one measurement.
  3. What is the first-line treatment for elevated lipids? Initially, we recommend lifestyle intervention, including more fruits, vegetables, fish, wholegrains and low-fat dairy products, with reduced intake of fruit-juice, sugar-sweetened beverages and foods, and decreasing salt. We also recommend physical activity and losing weight, if appropriate. The fact that we essentially recommend this diet for all children is partly why many advocate not testing lipids because it does not change recs unless you have serious disease, which is rare. To treat overall elevated cholesterol or LDL, we focus more on dietary fat intake, but to treat elevated TG, we focus more on sugar and carbohydrate intake.
  4. If children have higher lipid levels that don’t respond to diet or have familiar hypercholesterolemia (FH), what is the treatment? There is more controversy here as well! The NHLBI guidelines do not recommend medication for children under 10 unless they have severe primary hyperlipidemia or a high-risk condition associated with serious morbidity. For children with FH, statin treatment in childhood is associated with improved carotid thickness. For children ≥10 years, starting a statin is recommended for those who have persistent elevated LDL (range from 130-190 based on family history and risk factors) after 6 months of lifestyle changes, with the goal of lowering LDL to below the 95th percentile (≤130 mg/dl). The safety of statins for long-term use has not been adequately studied for children, so we usually consult a specialist before starting statins. Routine monitoring for muscle and hepatic toxicity with CPK and transaminase levels would be done for patients on statins.
  5. When do we refer to a specialist and which one? Referral to a specialist has been recommended for those with LDL ≥250 mg/dl and TG ≥500 mg/dl even before a trial of lifestyle management, or when more than one lipid-lowering medication may be needed (such as a bile acid sequestrant or cholesterol absorption inhibitor). Around the country, different specialists manage lipids; in our region, the Endocrine Division runs the lipid clinic so patients would be referred to them when needed.

2018-19 TOW #4: Sports Participation

Summer is primetime for pre-participation sports physicals. There has been much debate as to what should be included in routine testing and screening. Generally, we follow the AAP guidance for screening, and encourage use of the standardized tool adopted by multiple medical organizations, as below. We have a guideline developed for our UW General Peds division as well. Remember to refer to our wonderful local sports meds experts (like our esteemed APD, Dr. Celeste Quitiquit!) if you have questions.

Teaching materials for this week:

Take-home points for sports physicals:

  1. What are the key history questions we should include in sports physicals? Specific questions about key areas should include personal and family history, especially cardiac, bone and joint, asthma (and inhaler use), concussion or seizures, sickle cell, and infectious histories. Review weight and diet including attempted weight loss or gain, supplements to gain weight/muscle, and hydration and eating patterns. With females, review menstrual history.
  2. What are the components of cardiovascular screening? The American Heart Association recommends a 12-element screening tool that encompasses personal history, family history, and physical exam. This tool is incorporated into the Preparticipation Physical Evaluation, Fourth Edition (PPE-4) recommended by the AAP. A positive response or exam finding on any item should prompt referral to cardiology. A goal is to identify risk for and prevent sudden cardiac death, which happens in about 100 young athletes annually in the US. Unlike in other countries, we have not adopted routine ECG due to cost and number needed to screen.
  3. What are the critical parts of the exam? Vision, BP, thorough cardiac exam (murmurs-do valsalva, pulses, Marfan stigmata), musculoskeletal exam (strength, ROM, functional/sport-specific movements), neurologic exam (especially if previous concussion), and skin exam to look for infectious lesions.
  4. What are contraindications to full participation? These include
  • some cardiac diseases (discuss with cardiology)
  • Atlanto-axial instability (especially in Down syndrome or JIA)
  • Infectious diarrhea, conjunctivitis, or actively contagious skin lesions (e.g., HSV, MRSA)
  • Fever–increased risk of heat related illness and hypotension
  • Acute splenic enlargement-increased risk of rupture
  • Poorly controlled seizure disorder-especially for swimming, weight-lifting, sports involving heights
  • Hypertension–if> 5mm Hg above 99th percentile for age, avoid heavy lifting & high-static component sports

TOW #32: Heart murmurs

February is Heart Month. In honor of Valentine’s Day this week, we will do a heart-related topic and review one of the biggies in evaluating pediatric hearts: assessing heart murmurs!

Materials for this week:

Take-home points for heart murmurs:

  1. What do typical innocent murmurs sound like? These are typically vibratory (or musical), of low intensity, and best audible at the left-sternal border (LSB). They are usually midsystolic—never purely diastolic—and nonradiating. Their intensity varies with position-typically loudest lying down and decreased while sitting up. Innocent murmurs (like pathologic ones) are louder with fever, anemia, or any increased cardiac output. The two most common innocent murmurs are Still’s murmur (typically early systole vibratory “twangy” murmur at LLSB most common in ages 2-6) and pulmonary outflow murmurs (mid-systolic crescendo-decrescendo murmur at LUSB).
  2. What murmurs are loudest at LLSB and LUSB? At the left lower sternal border (LLSB), we are usually dealing with Still’s murmur but the most common pathologic murmur to consider is VSD – typically holosystolic and may radiate more than Still’s. Murmurs loudest at the LUSB: usually pulmonary outflow murmurs, but also consider supraclavicular murmur (also innocent) or ASD or pulmonary stenosis.
  3. What are two continuous murmurs? Common continuous murmurs in childhood are venous hum and PDA. Venous hum is an innocent murmur heard on the low anterior part of the neck lateral to the sternocleidomastoid muscle, but can extend below the clavicle (usually on the right). It is usually louder during diastole and while the patient is upright. PDA is the classic “machinery” like murmur heard most often during S2 over the second left intercostal space, or in the left infra- or supraclavicular region.
  4. What clinical features are suggestive of pathologic murmurs? Murmurs with long duration (pansystolic/holosystolic), greater intensity (grade≥3), and harsh quality are more suggestive of cardiac lesion/defect. Be concerned about murmurs in the setting of decreased exercise/activity tolerance, palpitations, chest pain, syncope, or a family history of congenital heart disease, arrhythmias, or sudden cardiac death. A systolic murmur that gets louder with Valsalva is consistent with hypertrophic cardiomyopathy (due to reduction of venous return to the heart and resultant narrowing of the left ventricular outflow).
  5. What further evaluation of murmurs should we consider? To avoid unnecessary costs, most often it is helpful to directly refer a suspected pathologic murmur to a pediatric cardiologist for further workup. If you are going to a study first, an EKG has the lowest cost and may help identify some patients at risk.