Nutritional Management of Children with Spinal Muscular Atrophy: A Toolkit Nora McCormick RD, CD University of Wisconsin Pediatric Pulmonary Center Trainee June 2015
Table of Contents
Overview of Basic Nutritional Needs………………...Page 3
Nutritional Assessment and Monitoring……………Page 7
Laboratory Monitoring…………………………………….Page 11 Commonly Encountered Issues………………………..Page 12 Amino Acid Diet………………………………………………Page 16
Additional Resources………………………………………Page 18 Works Cited……………………………………………………Page 19 Appendix………………………………………………………..Page 20
Nutritional management is a cornerstone of the treatment of spinal muscular atrophy. Although interventions may vary greatly based on the type of SMA bring treated, experts agree that proper nutrition can greatly improve the clinical outcomes for children with this condition1. Adequate nutrition is crucial to the maintenance of muscle mass and strength. Furthermore, children with this condition face a variety of feeding challenges: dysphagia, problems with fatty acid metabolism, and overnutrition are just a few examples. The management of tube feedings is also a component of care for children with SMA Type I and sometimes SMA Type II. This toolkit is a reference for healthcare providers, particularly dietitians, who wish to gain a basic background knowledge regarding the nutritional management of children with SMA. Ideally, an experienced pediatric dietitian is a part of the interdisciplinary team caring for patients with this disease. However, many dietitians do not receive training in the nutritional care of children with SMA1. A review of current guidelines, recommendations, and clinical experiences was conducted and synthesized, to improve ease of access to crucial information.
Overview of Basic Nutritional Needs
Energy: The energy needs of children with SMA are lower than healthy children of the same age and gender. • Calorie needs are calculated based on the height of the child in centimeters. The range of 7 – 14 calories per centimeter is typically used • Where a particular child with SMA falls within this range will depend on several factors, including type and severity, need for respiratory support, muscle tone, level of activity, and ability to eat orally2,3,4 Protein: The DRI for age can be followed. • Protein needs are generally in the range of 1 – 2 grams protein per kilogram2 Fat: Children with SMA do not metabolize fatty acids normally. • The guidelines for fat intake are based on clinical experience and observation. It is important to remember that the stronger a child is, the better fat is tolerated • For children under 1 year of age, it is important to ensure adequate fat in the diet to aid in brain development (approximately 45% of total energy) • Between the ages of 1 and 2, children often receive 20 – 30% of calories from fat 3
• For children over 2 years of age, total fat typically makes up 10 -‐ 30% of total energy o Those with SMA Type 1 usually tolerate diets that include 10 – 20% of calories from fat o Children with SMA Types II and III often tolerate diets that include up to 30% of calories from fat • Essential fatty acids (omega-‐3 and omega-‐6) should make up 5% of total energy in order to prevent essential fatty acid deficiencies4,5 **For more information regarding the secondary fatty acid oxidation disorder that is common in children with SMA, please refer to the 1999 article in Annals of Neurology by Crawford, et al. titled “Abnormal Fatty Acid Metabolism in Childhood Spinal Muscular Atrophy”10 Fluid: Children with SMA generally require more fluid than a healthy child of the same age due to greater insensible losses. • Type I: Approximately 10 – 35% increased fluid needs than healthy child of same age • Types II and III: Follow the DRI for age or use the Holliday-‐Segar method2,9 Carbohydrates: Depending on the severity of the condition, intake recommendations may be similar to a
child of the same age and gender who does not have SMA. • Since children with SMA Type I have very little muscle mass, they lack the ability to store sufficient glycogen. After age 1, they often need a diet that contains 70 – 80% of calories from carbohydrate to prevent low blood glucose levels • Carbohydrates should make up 45 – 65% of total energy intake in children with SMA Type II and III4 Fiber: As a general rule, the child’s age plus 5 equals the recommended grams of fiber per day. Importantly, fiber intake needs to be modified based on individual tolerance6. Vitamins and Minerals: The DRI for age can be followed. • Even though children with SMA have lower energy needs, their needs for vitamins and minerals is estimated to be similar to children of the same age and gender without SMA • In practice, it has been noted that children with SMA often require additional supplementation of vitamin D to reach appropriate serum levels. Calcium intake should also be assessed and supplemented if necessary3
**For more information regarding the general nutritional requirements of children with SMA, please follow this link: http://swoboda.genetics.utah.edu/?page_id=509 Then click on the Nutrition tab followed by “General Nutrition Guidelines for SMA Children”
Nutritional Assessment and Monitoring
• It is important to establish a baseline weight, length or height, and weight-‐for-‐length or BMI so that trends can be monitored o A nutrition-‐focused physical exam is also especially important for children with SMA, since weight-‐for-‐length and BMI alone cannot reliably predict nutritional status3 o Look at hair, skin, nails, and fat stores when performing a physical exam. Feel the body for any protruding bones o Be sure to determine if child is at risk for developing pressure sores Dietary Assessment: • Specifics will depend on mode of nutrition. In general, it is necessary to obtain a “typical day” diet recall or analyze a three-‐day food record o Macro-‐ and micronutrient intake should be analyzed and assessed o If the child is fed enterally, be sure to inquire about tube feeding volume and rate, in addition to formula and additives4 o If the child eats orally, be sure to inquire about any trouble chewing, swallowing, choking, or 7
gagging. Also ask how long it takes the child to complete a meal or snack. Determine if there are any foods the child avoids or used to be able to eat, but has trouble eating now3 o Inquire about stooling – how often the child stools, and if he or she has any trouble passing stools. When children become constipated, they can get full easily and may not want to eat or may have trouble tolerating tube feedings • It is important to analyze adequacy of intake, and make recommendations accordingly, in order to prevent under-‐ or overnutrition o Children with SMA Type I and severe Type II tend to be prone to undernutrition; children with less severe Type II and Type III may struggle with overnutrition7 o As children with SMA get older, their lean body mass decreases. This may result in over-‐ nutrition if energy intake is not adjusted4 **For more information regarding how to prevent under-‐ or overnutrition, please follow this link: http://muscle.ca/wp-‐ content/uploads/2012/11/fsma_nutrition_brochure_web .pdf. Refer to pages 25 -‐ 26. 8
Rate of Weight Gain: • Weight gain per day should be monitored closely at each visit • Children with SMA should have a slower weight gain velocity than a healthy child of the same age • It is more important to look at weight trends on the growth chart than to focus on specific numbers Weight for Length or BMI: • Due to their lower amounts of lean body mass, children with SMA should ideally fall somewhere within the 3rd to 25th percentile on the growth chart for BMI or weight for length • However, some children with SMA are below the 3rd percentile but look well-‐nourished on exam o Use weight for length until 24 months, and BMI thereafter
Length or Height:
• It is important that length-‐for-‐age or height-‐for-‐age does not fall below the 3rd percentile; falling below this threshold may indicate suboptimal nutritional status • Length or height may be difficult to measure in children with SMA using standard methods. Arm span, arm length, or tibia length may be used to approximate length or height3
Head Circumference: • Should be measured on children up until age 3 • Should fall between the 5th and 95th percentile7 **For more information regarding the monitoring nutrition and growth, please follow this link: http://muscle.ca/wp-‐ content/uploads/2012/11/fsma_nutrition_brochure_web .pdf. Refer to pages 8 – 12.
There is not currently a consensus regarding which particular biochemical labs should be used to assess nutritional status8. However, experienced clinicians recommend that the following labs be assessed on a regular basis, at least once per year and more frequently as needed:3,4 • Serum proteins, including prealbumin • Plasma Quantitative Amino Acid analysis (PQAA) • 25-‐hydroxy vitamin D • Fatty acid panel – Triene:Tetraene ratio as well as individual levels of linoleic and linolenic acid • Carnitine – Total, free, esterified carnitine • Comprehensive iron panel (hemoglobin, hematocrit, MCV, ferritin, iron, iron binding capacity) Additional lab work that may be recommended includes but is not limited to: • Liver function tests • Complete blood count • Comprehensive metabolic panel • Dual X-‐ray Absorptiometry (DXA) scan
Commonly Encountered Issues Gastrointestinal & Feeding Issues: Delayed gastric emptying, constipation, GERD, bloating and abdominal distention, dysphagia. • Constipation: may try prune juice, magnesium supplementation, increased fluid and/or fiber o Children with SMA do not always respond to typical constipation management strategies due to reduced muscle strength. Pharmacotherapy may be indicated • Feeding intolerance: Large volumes of formula are not typically tolerated. Also, children with SMA may display atypical symptoms of intolerance o Continuous feeds (often overnight) combined with bolus feeds of modest volume are commonly used o Symptoms to watch for include increased heart rate, sweating, and changes in respiratory rate • Chewing and swallowing issues: Decreased muscle tone may result in trouble chewing and swallowing and/or concern for aspiration o These issues may need to be assessed by a feeding specialist such as a speech pathologist o Modified textures and/or supplemental tube feeds may be required1,2,3
• Reflux: o Children with SMA who have a g-‐tube receive a Nissen fundoplication to lessen reflux and to prevent aspiration pneumonia o Other management strategies include keeping the volume of bolus feeds modest, avoiding irritating foods, and propping children who are unable to sit up at a 20 – 30 degree incline after feedings1,7 **For more information on commonly encountered feeding issues in children with SMA, please follow this link: http://muscle.ca/wp-‐ content/uploads/2012/11/fsma_nutrition_brochure_web .pdf. Refer to pages 7 and 19 – 24. Fat Malabsorption: • A lower fat diet and small, frequent meals may be better tolerated by children (over age 2) with SMA who eat orally • Carnitine supplementation may be considered to aid in fat metabolism in children with SMA type I and sometimes Type II3 13
Adjusting enteral feeds: • Feeds should be adjusted gradually. Begin by increasing or decreasing calories by approximately 5 -‐10% per day • When using elemental formulas, children may need up to 20% more protein than the DRI1 • The child may need increased protein without extra calories o May use amino acid powder such as Nutricia® Complete Amino Acid mix o May use other elemental formula options (Vivonex® T.E.N., Vivonex® RTF, or Vivonex® Plus) instead of, or in addition to, standard elemental formulas Inability to Fast: Generally, children with SMA Type I, or any infant under 1 year with SMA, should not be allowed to fast for more than 6 hours because of their insufficient glycogen stores. Children with SMA Types II and III should not fast for more than 8-‐12 hours • Enteral and oral feeding schedules should be recommended keeping fasting restrictions in mind • Parenteral nutrition may be required in illness or in surgical situations where oral/enteral intake is not allowed or not possible
**For more information regarding nutrition during illness for children with SMA, please follow this link: http://columbiasma.org/docs/living/General-‐Nutrition-‐ Guidelines-‐in-‐SMA-‐Nutrition-‐Handout.pdf. Letter of Medical Necessity: Refer to the Appendix for a sample letter of medical necessity • May have to be written and faxed to durable medical equipment company for specialty formula, supplemental amino acid powder and other specialized nutritional requirements • Social work, case management, or care coordination services can often assist with writing a letter of medical necessity **For more information regarding the management of commonly encountered nutritional issues in children with SMA, please follow this link: http://jcn.sagepub.com/content/22/8/1027.full.pdf+htm l
Amino Acid Diet
Some families choose to provide an elemental amino acid-‐based diet to their child with SMA Type I and occasionally SMA Type II. This diet does not have a substantial amount of scientific evidence to back its effectiveness, but it is important to be aware of and understand it given its popularity in the SMA community. Many parents believe this diet improves the respiratory health of their children. Here are the basics: • Cow’s milk and soy-‐based formulas are eliminated • Elemental formulas are typically used as the basis for the diet, along with additives such as Pedialyte®, fruit juice, human milk, or dairy-‐free and soy-‐free beverages. Although human milk contains intact proteins, it is often very well tolerated in children of all ages and with all types of SMA • Supplements such as carnitine, coenzyme Q10, antioxidants, probiotics, and B-‐vitamins are often included • Protein remains in the range of 1-‐2 grams per kilogram body weight. Protein sources include elemental formula and amino acid powders • Carbohydrates make up the majority of calories. Sources include elemental formula and additives such as fruit juice, fruit and vegetable purees, and dairy-‐free/soy-‐free beverages
• Fat is variable depending on age and tolerance. Elemental formulas may be low in fat, so alternative sources include safflower oil, evening primrose oil, flax oil, walnut oil, omega 3-‐6-‐9 blends, mashed avocado, and omega-‐3 fatty acid supplements. Be aware that avocado does not contain adequate amounts of omega-‐3 and omega-‐ 6 fatty acids when it is used as the sole source of fat • Commonly used formulas include Tolerex® and Vivonex® Pediatric o Tolerex® contains 1.3% kilocalories from fat – children will require additional sources of omega-‐3 and omega-‐6 fatty acids o Vivonex® Pediatric contains 25% kilocalories from fat – children may not require additional sources of fat5 • If children remain on the amino acid diet long-‐ term, they will need to be monitored for issues related to the high concentration of carbohydrates contained in the diet, such as blood sugar levels, triglycerides, and liver enzymes4 **Please visit http://www.aadietinfo.com for an example of an informational website that families might visit for more information about the amino acid diet.
Additional Resources Cure SMA – http://www.curesma.org Muscular Dystrophy Association -‐ http://www.mda.org SMA Foundation -‐ http://www.smafoundation.org Fight SMA -‐ http://fightsma.org Essential Fatty Acid Panel: Mayo Clinic Interpretive Handbook -‐ http://www.mayomedicallaboratories.com/interpretiv e-‐guide/index.html?alpha=F&unit_code=82426
1. Sproule D. Living with SMA: nutritional care. Columbia University Spinal Muscular Atrophy Clinical Research Center Web site. n.d. Available at: http://columbiasma.org/docs/living/General-‐Nutrition-‐Guidelines-‐in-‐SMA-‐ Nutrition-‐Handout.pdf. Accessed May 6, 2015. 2. Godshall B, Wong B. Spinal muscular atrophy: an overview of disease and nutrition. PNPG Building Blocks for Life. 35:1-‐4. Winter 2012. 3. Seffrood E, Schroth M. Nutrition for orally fed children with spinal muscular atrophy. PNPG Building Blocks for Life. 35:5-‐7. Winter 2012. 4. Davis RH, Swoboda KJ. Nutrition for enterally fed children with spinal muscular atrophy. PNPG Building Blocks for Life. 35:8-‐14. Winter 2012. 5. Marcus M. Overview on the principles, implementation, and management of the SMA amino acid diet and common complementary therapies in SMA nutrition. PNPG Building Blocks for Life. 35:15-‐17. Winter 2012. 6. Swoboda KJ, Wiebke G. General Nutrition Guidelines for SMA Children. University of Utah School of Medicine Pediatric Muscle Disorders Research Program Web site. 2007. Available at: http://swoboda.genetics.utah.edu/?page_id=509. Accessed May 6, 2015. 7. Godshall B, Hurst R, Marcus M, Mason T, Meguiar A, Rioch K, Rizzo C, Schroth M, Seffrood E, Shish J, Swoboda, K, Wolff J, Wong B. Nutrition Basics: Fostering Health and Growth for Spinal Muscular Atrophy. Elk Village, IL: Families of Spinal Muscular Atrophy; 2011. 8. Wang CH, Finkel RS, Bertini ES, Schroth M, Simonds A, Wong B, Aloysius A, Morrison L, Main M, Crawford TO, Trela A. Consensus statement for standard of care in spinal muscular atrophy. J Child Neurol. 2007;22(8):1027-‐49. 9. Holliday MA and Segar WE. The maintenance need for water in parenteral fluid therapy. Pediatrics 1957;19; pg 823-‐832. 10. Crawford TO, Sladky JT, Hurko O, Besner-‐Johnston A, Kelley RI. Ann Neurol. 1999;45(3):337-‐43.
SAMPLE LETTER OF MEDICAL NECESSITY
Date Name: Sex: DOB: Prescriber: Problem List: (EXAMPLES WITH ICD-‐ 9 and 10 CODES) Spinal muscular atrophy (ICD 9 Code 335.0 and ICD 10 Code G12.9) Dysphagia (ICD 9 Code 787.20 and ICD 10 Code R13.10) Gastrostomy Tube (ICD 9 Code V44.1 and ICD 10 Code Z93.1) Fatty acid oxidation disorder (ICD 9 Code 277.85 and ICD 10 Code E71.318) Anthropometric Data (Include 2-‐3 weights and heights) Calorie needs: example 700 kcal/day (include kcals/kg and kcals/cm) Formula: examples include human donor milk, Vivonex Pediatric, Tolerex, Nutricia Complete Amino Acid mix Formula amount goals: 20 ounces per day, 1 packet per day Method for formula administration: g-‐tube with bolus and continuous feedings, j-‐ tube with continuous feedings Additional oral diet: might read 100% of needs via enteral feeding tube OR oral intake supplies % of calorie intake ** Keep in mind, insurance companies will often not cover enteral formula if it doesn’t comprise >50% of calorie needs Rational: For human milk: X ounces of human breast milk is medically necessary for this patient on a daily basis. It provides adequate calories, an easily digestible source of protein and essential fatty acids. Children with SMA have a problem with fatty acid metabolism but are able to tolerate the fat found in breast milk. This patient has been unable to gain weight without the addition of breast milk to diet (show evidence with weights and literature if needed). For an amino acid based formula: X formula is medically necessary for this patient. Children with SMA have a problem with fatty acid metabolism and need to follow a low fat diet. This formula provides less fat than a traditional formula. They also have problems with delayed gastric emptying and need proteins in the form of free amino acids since they are easily absorbed.
For an amino acid supplement: X is medically necessary for this patient. Children with SMA have very low calorie needs but need adequate protein. This provides the needed protein but without the addition of excess calories. If you have any questions, please contact my office at (phone). Sincerely, MD Signature