Neonatal Nutrition, Growth and Neurodevelopment: It's not all about weight gain! Sara Ramel, MD Division of Neonatology University of Minnesota Masonic Children’s Hospital Minneapolis, MN Optimizing Neurodevelopment Infections Gestational Age Socioeconomic Status IVH Nutrition Objectives • Understand the impact of linear growth and FFM gains, as well as weight gain on later neurodevelopment in preterm infants. • Discuss the impact of both caloric and protein intake on later growth and developmental outcomes in preterm infants, as well as available methods of fortification for optimizing outcomes. Brain Development through Term Gestation Brain Development throughout Infancy and Childhood Thompson & Nelson, 2001 Critical Periods • All nutrients are important for brain growth and development • Nutrients that support basic neuronal metabolism and differentiation – Proteins, glucose, specific fats – Iron, Zinc, Copper, Iodine • Rapidly developing systems at the time of preterm birth – Hippocampus learning and memory – Myelin speed of processing – Cerebellum balance, motor integration and cognition Preterm Infants Undergo Postnatal Growth Failure • Growth is a marker of macronutrient status • Postnatal growth failure is common among VLBW infants – Unable to recover prior to discharge – Not restricted to those extremely small infants Ehrenkranz et al. Pediatrics 1999 Growth Failure continues to be a problem! • Growth failure rates are improving. • Growth failure is still a problem. • Growth failure is occurring at a critical time in development Horbar et al. Pediatrics 2015. Greater Postnatal Weight Gain Benefits Neurodevelopment in Premature Infants Any Neurodevelopmental Impairment Bayley Mental Development Index <70 Psychomotor Development Index <70 Cerebral Palsy Percent with Outcome at 18 mos 60 50 40 30 20 10 0 Quartile 1 Quartile 2 Quartile 3 Quartile 4 Ehrenkranz et al., Pediatrics, 2006 Linear Growth in VLBW infants Ramel SE et al. Neonatology. 2012; 102:19-24. Linear Growth Failure Studies • Belfort; birth <33 wks: Mean length z-score (LZ) is 1-SD below reference population at term and 4 months, equal to reference by 18 months CGA • Belfort; birth ≤37 wks: Length remained lower than reference population out to 18 months CGA • Ramel; birth AGA <30 wks: Reduction in LZ from birth to discharge, did not return to baseline by 24 months CGA Belfort et al. J Pediatr 2013;163(6):1564–9.e2 Belfort et al. Pediatrics 2011;128:e899–906. Ramel et al. Neonatology 2012;102:19–24. • 62 AGA VLBW infants (<30 weeks GA) • Improved linear growth throughout the first year of life →Improved neurodevelopment at 24 months • ↑ 1 z-score at discharge = ↑ 8 points (language) • ↑ 1 z-score at 4 and 12 months = ↑ 4.5 points (cognition) Linear Growth and Neurodevelopment • Infants born <33 weeks (mean=30 weeks) • Linear growth from term to 4 months CGA associated with higher motor scores at 18 months • Infants born ≤37 weeks and LBW (mean=33 weeks and 1800 grams) • Increased linear growth from term to 4 months CGA, decreased odds of IQ <85 at 8 and 18 years • <1250g AGA and SGA infants • Linear growth from birth to 2 years of age correlated with PDI and CP Belfort et al. Pediatrics 2011;128:e899–906. Belfort et al. J Pediatr 2013;163(6):1564–9.e2 Latal-Hajnal et al. J Pediatr 2003;143(2):163-7. • Linear growth prior to 1 year of age has the highest impact on long term neurodevelopment in preterm • Critical time period for intervention based on developmental window of brain. Thompson and Nelson. American Psychologist. 2001 Body Composition • Preterm infants have increased adiposity and decreased FFM at term CGA compared to term counterparts • Abnormal distribution – increased intra-abdominal fat at term Ramel et al. JPGN 2011;53(3):333-8. Johnson et al. Pediatrics 2012; 130 (3):E640-9. Uthaya et al. Pediatric Research 2005; 57(2):211-5. FFM Gains and Neurodevelopment • 16 AGA infants, mean birth GA ~30 weeks • Body Composition measurements via ADP at Term and 4 months CA • Visual pathway assessment via pattern reversal Visual Evoked Potentials FFM Gains and Neurodevelopment • Increased FFM at term and 4 months CGA is associated with faster speed of visual processing at 4 months CGA Bold line = Visual Evoked Potential in infant with relatively high FFM Dashed line = Visual Evoked Potential in infant with relatively low FFM From Pfister KM et al. Pediatr Res 2013;74(5):576–83 Birth to Term FFM gains and Neurodevelopment • Increased FFM gains (10gms/wk)= Improved motor (2pts) and cognitive (3pts) scores • Increased FM gains did not improve scores Ramel et al. E-PAS 2015:753028. Manuscript under review. FFM gains and Neurodevelopment • FFM gains in preterm infants (<36 weeks) from 4 months CA to 4 years were positively associated with cognition at 4 years of age • These associations were not seen in term infants or for FM changes Scheurer et al. E-PAS 2015: 752440 Manuscript in preparation Nutrition Matters! Energy and Protein Weight gain, Linear Growth and Fat-Free Mass Gains Improved Neurodevelopment Carbohydrates • Energy intake is the primary determinant of weight gain • Carbohydrates (ie. glucose) are the main fuel source for the brain • Improved caloric intake associated with – Increased FFM accretion prior to discharge – increased FFM accretion at 4 months CGA – increased linear growth out to 24 months CGA • Increases in caloric intake NOT associated with increased FM Ramel et al. Manuscript under review. Ramel et al. Neonatology 2012;102:19–24 Ramel et al. JPGN 2011;53(3):333-8 • Diet A: 3.7 g/kg/d of protein and 129 kcal/kg/d • Diet B: 4.2 g/kg/d and 150 kcal/kg/d • Diet C: 4.7 g/kg/d and 150 kcal/kg/d • Similar gains in FFM to reference fetus Costa-Orvay et al. J Nutr 2011 • Introduction of new strategies: – Higher max amounts of protein and IL – Earlier enteral feeds and faster more frequent adjustment – New prescription ordering system • Findings: – Higher caloric intake – Improved weight gain – Improved HC – Similar % body fat – Lower rates of sepsis Energy has an independent effect on MDI Every 10 kcal/kg/d increase in energy during week 1 4.6point increase in MDI on 18 month Bayley Stephens et al, Pediatrics 2009;123(5):1337-43 • n=76 • Standard nutrient – term formula – Un-supplemented DEBM • • • • High nutrient group Neurologically normal at 8y WISC III or WAIS-R MRI (1.5T) – T1 images – brain volume & segmentation Isaacs et al Ped Res 2008 Fats • Fats are necessary for efficient neural processing – Myelin synthesis, cell membrane fluidity, synaptasome formation • Fear of providing lipids early – Lung disease, increased sepsis, thrombocytopenia, CNS damage, hyperbilirubinemia – Recent evidence that IL (up to 2-3 g/kg/day) on DOL 1 are well-tolerated by preterm infants Viaardingerbroek H et al. AJCN 2012 Salama GS et al. Clin Med Insights Pediatr 2015 • 110 VLBW AGA preterm infants (26-32 weeks) • 0.5 vs 2 g/kg/day IL on first day of TPN • Experimental group: – Increased energy intake – Decreased NEC and ROP – Increased rate of AGA at discharge Drenckpohl D. Pediatrics. 2008 • 48 VLBW preterm infants born <28 weeks • Infants received a mean of 4.2±1.3 grams/kg/day • Increased lipid intake in first 14 days is associated with improved DQ at 1 year of age dit Trolli et al. Early lipid supply and neurological development at one year in VLBW preterm infants. Early Hum Dev 2012. Energy-Summary • Providing adequate calories promotes improved growth in weight, length and fatfree mass gains • Increased calories and lipids provided early are associated with improved neurodevelopment • Increased calories provided prior to term have not been associated with increased gains in fat mass Protein • Protein is necessary for neurogenesis, dendritic arborization, synaptogenesis and myelin production • Protein accretion is indexed by linear growth and FFM • Historically limited due to safety concerns • Parenteral amino acid administration of 3-3.5 g/kg/d on the first day of life is safe and results in increased protein accretion – 4.5-5.5g/kg/day on subsequent days are now thought to be safe and associated with improved linear growth Ibrahim HM. J Pernatology, 2004. Thureen PJ. Pediatr Res, 2003. Olsen IE. JPGN, 2014. • Cumulative hospital protein deficit negatively associated with FFM at term and 4 months CGA • Increased protein provision in first week associated with increased gains in FFM, not FM, throughout hospitalization Ramel et al. JPGN 2011;53(3):333-8 Ramel et al. Manuscript under review Protein and Growth • Biasini, 2012: infants 23-30 weeks – normal vs extra protein supplementation (enteral) – Improved in-hospital and post* discharge head and linear growth – Improved developmental testing at 3 months CGA • Olsen, 2014: randomized trial of new fortifier – High protein group: 4.6-5.5 g/kg/day – Improved length z-scores without increased weight z-scores Biasini et al. J Matern Fetal Neonatal Med, 2012 Olsen et al. JPGN, 2014 Protein intake – independent effect on MDI Every 1 g/kg/d increase in protein during week 1 8.2point increase in MDI on 18 month Bayley Stephens et al, Pediatrics 2009;123(5):1337-43 • Influence of change in TPN solutions on later growth and neurodevelopment • No difference between before and after groups in: clinical outcome growth z-scores at 4 weeks 18 month developmental scores • Levels of protein given were below recommended levels in both groups • Enteral protein intake in the first two weeks of life was positively associated with neurodevelopment (both cognitive and motor) at 18 months Protein-Summary • Protein provided at 4-4.5 (possibly up to 5.5) grams/kg/day is safe • Adequate provision of protein leads to improved gain in weight, length, head circumference and FFM • Increased provision of protein is associated with improved developmental outcomes Enteral Nutrition: Breast Milk Fortification • Breast milk is best… – – – – – Immunoprotective properties Improved developmental outcomes Improved tolerance and lower rates of NEC Nutrient content is variable Nutrient content is insufficient • Standard vs. Adjustable vs Target Fortification – Close growth monitoring – Frequent lab draws – Breast Milk Analyzers Adamkin. Clin Perinatol. 2014 Rochow. Current Opinion. 2015 Breast Milk Fortification Adamkin. Clin Perinatol. 2014 Post-Term Supplementation • Randomized infants to fortification at discharge or solely mom’s milk • Found improved growth in weight, length and head circumference • Improved weight gain and linear growth persisted throughout the 1st year • No differences in body composition Aimone A. JPGN. 2009 Post-Term Supplementation • Few studies have evaluated the influence of post-discharge nutrition on neurodevelopment – Improved visual development at 4 and 6 months – No differences on 18 month Bayley • Multiple Cochrane reviews: – preterm formula and fortified breast milk after discharge from the NICU improve growth, but not enough evidence for neurodevelopment Post-Term Supplementation • Reasons?? • ESPGHAN Committee on Nutrition – Lack of data recommends until 40– Continued inadequate fortification 52 weeks in those with – Inappropriately balanced suboptimal weight strategy (energy vs protein) – Missed the crucial window for intervening Aggett P.J. JPGN. 2006 Groh-Wargo. ICAN. 2014 Monitor closely and optimize early! • Avoid early deficits when able – Optimize TPN • Protein and Lipids begin on DOL 1 – Continue TPN while advancing feeds • Do not stop TPN before fortifying milk • Monitor growth closely – Not only weight gain… monitor length, proportionality and body composition as able • Increase calories and protein when growth is poor – Increased nutrition ≠increased fat in preterm neonates • Consider post-discharge supplementation for at-risk infants