Higher Docosahexaenoic acid, lower Arachidonic acid and reduced lipid tolerance with high doses of a lipid emulsion containing 15% fish oil: A randomized clinical trial

Comparative effectiveness of two lipid emulsions in preventing retinopathy of prematurity in preterm infants requiring parenteral nutrition

OBJECTIVES

The main aim was to compare the effects of 2 parenteral lipid emulsions on retinopathy of prematurity (ROP) incidence, severity, and need for treatment. Secondary aim was to compare the effect on weight gain in the first 6 weeks of life.

METHODS

Single-center, observational, retrospective study analyzing preterm infants with a gestational age (GA) <31 weeks and a birth weight <1251 g born between April 2015 and December 2018. The infants' medical records were reviewed to collect clinical data. Parenteral nutrition (PN) details were obtained from the hospital pharmacy database.

RESULTS

In total, 180 patients were included: 90 received ClinOleic® and 90 received SMOFlipid®. No significant differences were observed for the incidence of ROP (40% in ClinOleic® group and 41% in SMOFlipid® group, p=.88) or ROP requiring treatment (4% and 10%, respectively, p=.152). Weekly weight gain was similar in the 2 groups.

CONCLUSIONS

This study showed no difference between the 2 groups regarding ROP, ROP requiring treatment, or weekly weight gain in the first 6 weeks of life.

Comparative effectiveness of two lipid emulsions in preventing retinopathy of prematurity in preterm infants requiring parenteral nutrition

OBJECTIVES

The main aim was to compare the effects of two parenteral lipid emulsions on retinopathy of prematurity (ROP) incidence, severity, and need for treatment. Secondary aim was to compare the effect on weight gain in the first 6 weeks of life.

METHODS

Single-center, observational, retrospective study analyzing preterm infants with a gestational age < 31 weeks and a birth weight < 1,251 g, born between April 2015 and December 2018. The infants' medical records were reviewed to collect clinical data. Parenteral nutrition details were obtained from the hospital pharmacy database.

RESULTS

In total, 180 patients were included: 90 received ClinOleic® and 90 received SMOFlipid®. No significant differences were observed for the incidence of ROP (40% in ClinOleic® group and 41% in SMOFlipid® group, p=0.88) or ROP requiring treatment (4% and 10% respectively, p=0.152). Weekly weight gain was similar in the two groups.

CONCLUSIONS

This study showed no difference between the two groups regarding ROP, ROP requiring treatment or weekly weight gain in the first 6 weeks of life.

ROP: 80 Years after Its Detection - Where Do We Stand and How Long Will We Continue to Laser?

BACKGROUND

Retinopathy of prematurity (ROP), a potentially blinding disease, is increasing worldwide because of the increased survival of extremely preterm and preterm infants born where oxygen monitoring and ROP screening programs are insufficient. Repeated retinal examinations are stressful for infants, and laser photocoagulation treatment for sight-threatening ROP is destructive. The use of anti-VEGF agents instead of lasers is widespread but requires a long-term follow-up because of late recurrence of the disease. In addition, the optimal anti-VEGF agent dosage and long-term systemic effects require further study.

SUMMARY

Interventions preventing ROP would be far preferable, and systemic interventions might promote better development of the brain and other organs. Interventions such as improved oxygen control, provision of fresh maternal milk, supplementation with arachidonic acid and docosahexaenoic acid, and fetal hemoglobin preservation by reducing blood sample volumes may help prevent ROP and reduce the need for treatment. Free readily available online tools to predict severe ROP may reduce unnecessary eye examinations and select, for screening, those at a high risk of needing treatment.

KEY MESSAGES

Treatment warranting ROP is a sign of impaired neurovascular development in the central nervous system. Preventative measures to improve the outcomes are available. Screening can be refined using tools that can predict severe ROP. Laser treatment and anti-VEGF agents are valuable treatment modalities that may complement each other in recurrent ROP.

Therapeutic Effects of Anti-Inflammatory and Anti-Oxidant Nutritional Supplementation in Retinal Ischemic Diseases

Appropriate nutrients are essential for cellular function. Dietary components can alter the risk of systemic metabolic diseases, including cardiovascular diseases, cancer, diabetes, and obesity, and can also affect retinal diseases, including age-related macular degeneration, diabetic retinopathy, and glaucoma. Dietary nutrients have been assessed for the prevention or treatment of retinal ischemic diseases and the diseases of aging. In this article, we review clinical and experimental evidence concerning the potential of some nutritional supplements to prevent or treat retinal ischemic diseases and provide further insights into the therapeutic effects of nutritional supplementation on retinopathies. We will review the roles of nutrients in preventing or protecting against retinal ischemic diseases.

Nutritional interventions to prevent retinopathy of prematurity

Very preterm infants are at high risk of growth failure. Poor weight gain is a prominent risk factor for retinopathy of prematurity (ROP) and optimizing nutrition could potentially promote growth and reduce ROP. Most infants at risk of ROP need parenteral nutrition initially and studies of enhanced parenteral provision of lipids and amino acids have suggested a beneficial effect on ROP. Higher amino acid intake was associated with lower incidence of hyperglycemia, a risk factor for ROP. For very preterm infants, providing unpasteurized fortified raw maternal breast milk appears to have a dose-dependent preventive effect on ROP. These infants become deficient in arachidonic acid (ArA) and docosahexaenoic acid (DHA) after birth when the maternal supply is lost. Earlier studies have investigated the impact of omega-3 fatty acids on ROP with mixed results. In a recent study, early enteral supplementation of ArA 100 mg/kg/d and DHA 50 mg/kg/d until term equivalent age reduced the incidence of severe ROP by 50%. IMPACT: Previous reviews of nutritional interventions to prevent morbidities in preterm infants have mainly addressed bronchopulmonary dysplasia, brain lesions and neurodevelopmental outcome. This review focusses on ROP. Neonatal enteral supplementation with arachidonic acid and docosahexaenoic acid, at levels similar to the fetal accretion rate, has been found to reduce severe ROP by 50% in randomized controlled trials.

The effects of parenteral fish oil on neurodevelopment in preterm infants: A narrative review

OBJECTIVE

This narrative review aimed to summarize studies assessing the effects of parenteral fish oil on neurodevelopment in preterm infants.

METHODS

PubMed was searched (July 1985 to October 2023). We reviewed randomized controlled trials, and observational studies assessing intravenous lipid emulsion with fish oil in preterm infants (born less than 37 weeks' gestation), that reported long-term neurodevelopmental outcomes.

RESULTS

We identified four publications relating to three randomized controlled trials in addition to four cohort studies. Study designs and outcomes were heterogenous and precluded meta-analyses. Results of trials were null for a selection of neurodevelopmental outcomes, however possible benefits of parenteral fish oil supplementation for neurodevelopment was reported in three cohort studies. Certainty of the evidence is hindered by methodological limitations of available trials and observational studies.

CONCLUSIONS

Further research is required to firmly establish the effects of parenteral fish oil on preterm neurodevelopment.

Effect of SMOF lipid emulsion on physical growth and extrauterine growth retardation in very preterm infants: Insights from a multicenter retrospective cohort study

OBJECTIVE

The aim of this study was to investigate the effects of soybean, medium-chain triacylglycerols (MCTs), olive oil, and fish oil (SMOF) on short-term clinical outcomes, physical growth, and extrauterine growth retardation (EUGR) in very preterm infants.

METHODS

This was a multicenter retrospective cohort study of very preterm infants hospitalized in neonatal intensive care units at five tertiary hospitals in China between January 2021 and December 2021. According to the type of fat emulsion used in parenteral nutrition (PN), eligible very preterm infants were divided into the MCTs/long-chain triacylglycerol (MCT/LCT) group and SMOF group. Change in weight z-score (weight Δz) between measurements at birth and at 36 wk of postmenstrual age or at discharge, the incidence of EUGR, and short-term clinical outcomes between the two groups were compared and analyzed.

RESULTS

We enrolled 409 very preterm infants, including 205 in the MCT/LCT group and 204 in the SMOF group. Univariate analysis showed that infants in the SMOF group had significantly longer duration of invasive mechanical ventilation and PN, longer days to reach total enteral nutrition, and a higher proportion of maximum weight loss than those in MCT/LCT group (all P < 0.05). After adjusting for the confounding variables, multifactorial logistic regression analysis of short-term clinical outcomes showed that SMOF had protective effects on PN-associated cholestasis (odds ratio [OR], 0.470; 95% confidence interval [CI], 0.266-0.831) and metabolic bone disease of prematurity (OR, 0.263; 95% CI, 0.078-0.880). Additionally, SMOF was an independent risk factor for lower weight growth velocity (β = -0.733; 95% CI, -1.452 to -0.015) but had no effect on the incidence of EUGR (OR, 1.567; 95% CI, 0.912 to -2.693).

CONCLUSION

Compared with MCT/LCT, SMOF can reduce the risk for PN-associated cholestasis and metabolic bone disease of prematurity in very preterm infants and has a negative effect on growth velocity but has no effect on the incidence of EUGR.

In parenteral nutrition-fed piglets, fatty acids vary by lipid emulsion and tissue sampled

BACKGROUND

Children with intestinal failure without liver disease may be given soy-based lipid emulsion (SLE) or mixed lipid emulsion (MLE; containing soy, medium-chain triglyceride, olive, and/or fish oils). Both differ in essential fatty acid content: MLE has added arachidonic acid (AA) and docosahexaenoic acid (DHA). The aim of this study, in neonatal piglets, was to compare serum and tissue fatty acid composition when the emulsions were given at unrestricted doses.

METHODS

We compared SLE (n = 15) and MLE (n = 15) at doses of 10-15 g/kg/day in parenteral nutrition (PN). On day 14 we collected serum and tissues. Using gas-liquid chromatography, percentage fatty acids were measured in serum, brain, and liver phospholipid. Comparisons were made to reference values from litter-matched controls (n = 8).

RESULTS

Comparing median values, linoleic acid (LA) was lower for MLE vs SLE in serum (-27%), liver (-45%), and brain (-33%) (P < 0.001). AA was lower for MLE in serum (-25%), liver (-40%), and brain (-10%). DHA was higher for MLE in serum (+50%), liver (+200%), and brain (+10%). AA levels were lower for MLE vs control piglets in serum (-81%), liver (-63%), and brain (-9%). DHA levels were higher in serum (+41%), liver (+38%), and brain (+19%).

CONCLUSION

This study in piglets has shown that, at unrestricted doses, MLE treatment is associated with low serum and tissue AA compared with SLE and healthy litter-matched controls. Although not yet proven, low tissue AA levels may have functional consequences, and these data support current practice avoiding MLE dose restriction.

Monitoring and management of hypertriglyceridemia in extremely low birth weight neonates receiving intravenous lipid emulsions: A national survey

AIM

To assess the practice variation of defining, monitoring and managing hypertriglyceridemia (HTG) in extremely low birth weight neonates receiving intravenous lipid emulsions (IVLE).

METHODS

An 8-question survey created via the web survey site Qualtrics was distributed to neonatologists, neonatal nurse practitioners and fellows within the Section of Neonatal-Perinatal Medicine email directory list in the United States and Canada. Survey results were obtained between August and September 2022.

RESULTS

There were 249 respondents from approximately 4000 members within the Section of Neonatal-Perinatal Medicine. Responses were documented as a frequency (percentage) with a margin of error of plus or minus 6.2 %. Most respondents were neonatologists, individuals practicing for >10 years and reported a unit-based policy for IVLE initiation and advancement. The definitions of HTG varied among respondents, with the majority (42.7 %) reporting a defining threshold of >200 mg/dL. Nineteen percent of respondents reported not routinely monitoring serum triglyceride concentrations with variable triglyceride monitoring intervals reported by other survey respondents. Regarding elevated triglyceride concentrations, 19.0 % reported decreasing the IVLE rate and checking triglyceride concentrations until normalization; 14.6 % reported IVLE discontinuation and monitoring triglyceride concentrations until normalization; 61.9 % reported using a combination of the above practices; and 4.4 % reported individualized practices for IVLE management with elevated triglyceride concentrations.

CONCLUSION

This survey demonstrates a high variation in defining, monitoring and managing HTG in extremely low birth weight neonates and emphasizes the need for studies to better guide this practice.

Parenteral Nutrition in the Neonatal Intensive Care Unit: Intravenous Lipid Emulsions

Intravenous lipid emulsions (ILEs) are a source of nonprotein calories and fatty acids and help promote growth in preterm infants and infants with intestinal failure. An ILE dose and oil source determines its fatty acid, phytosterol, and vitamin E delivery. These factors play a role in the infant's risk for essential fatty acid deficiency and cholestasis, and help modulate inflammation, immunity, and organ development. This article reviews different ILEs and their constituents and their relationship with neonatal health.

Guidelines for parenteral nutrition in preterm infants: The American Society for Parenteral and Enteral Nutrition

BACKGROUND

Parenteral nutrition (PN) is prescribed for preterm infants until nutrition needs are met via the enteral route, but unanswered questions remain regarding PN best practices in this population.

METHODS

An interdisciplinary committee was assembled to answer 12 questions concerning the provision of PN to preterm infants. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) process was used. Questions addressed parenteral macronutrient doses, lipid injectable emulsion (ILE) composition, and clinically relevant outcomes, including PNALD, early childhood growth, and neurodevelopment. Preterm infants with congenital gastrointestinal disorders or infants already diagnosed with necrotizing enterocolitis or PN-associated liver disease (PNALD) at study entry were excluded.

RESULTS

The committee reviewed 2460 citations published between 2001 and 2023 and evaluated 57 clinical trials. For most questions, quality of evidence was very low. Most analyses yielded no significant differences between comparison groups. A multicomponent oil ILE was associated with a reduction in stage 3 or higher retinopathy of prematurity (ROP) compared to an ILE containing 100% soybean oil. For all other questions, expert opinion was provided.

CONCLUSION

Most clinical outcomes were not significantly different between comparison groups when evaluating timing of PN initiation, amino acid dose, and ILE composition. Future clinical trials should standardize outcome definitions to permit statistical conflation of data, thereby permitting more evidence based recommendations in future guidelines. This guideline has been approved by the ASPEN 2022-2023 Board of Directors.

Modification of serum fatty acids in preterm infants by parenteral lipids and enteral docosahexaenoic acid/arachidonic acid: A secondary analysis of the Mega Donna Mega trial

BACKGROUND & AIM

Preterm infants risk deficits of long-chain polyunsaturated fatty acids (LCPUFAs) that may contribute to morbidities and hamper neurodevelopment. We aimed to determine longitudinal serum fatty acid profiles in preterm infants and how the profiles are affected by enteral and parenteral lipid sources.

METHODS

Cohort study analyzing fatty acid data from the Mega Donna Mega study, a randomized control trial with infants born <28 weeks of gestation (n = 204) receiving standard nutrition or daily enteral lipid supplementation with arachidonic acid (AA):docosahexaenoic acid (DHA) (100:50 mg/kg/day). Infants received an intravenous lipid emulsion containing olive oil:soybean oil (4:1). Infants were followed from birth to postmenstrual age 40 weeks. Levels of 31 different fatty acids from serum phospholipids were determined by GC-MS and reported in relative (mol%) and absolute concentration (μmol l-1) units.

RESULTS

Higher parenteral lipid administration resulted in lower serum proportion of AA and DHA relative to other fatty acids during the first 13 weeks of life (p < 0.001 for the 25th vs the 75th percentile). The enteral AA:DHA supplement increased the target fatty acids with little impact on other fatty acids. The absolute concentration of total phospholipid fatty acids changed rapidly in the first weeks of life, peaking at day 3, median (Q1-Q3) 4452 (3645-5466) μmol l-1, and was positively correlated to the intake of parenteral lipids. Overall, infants displayed common fatty acid trajectories over the study period. However, remarkable differences in fatty acid patterns were observed depending on whether levels were expressed in relative or absolute units. For example, the relative levels of many LCPUFAs, including DHA and AA, declined rapidly after birth while their absolute concentrations increased in the first week of life. For DHA, absolute levels were significantly higher compared to cord blood from day 1 until postnatal week 16 (p < 0.001). For AA, absolute postnatal levels were lower compared to cord blood from week 4 throughout the study period (p < 0.05).

CONCLUSIONS

Our data show that parenteral lipids aggravate the postnatal loss of LCPUFAs seen in preterm infants and that serum AA available for accretion is below that in utero. Further research is needed to establish optimal postnatal fatty acid supplementation and profiles in extremely preterm infants to promote development and long-term health.

CLINICAL TRIAL REGISTRY

ClinicalTrials.gov, identifier: NCT03201588.

Intestinal Failure-Associated Liver Disease and Growth Pre- and Post-Transition to a Composite Lipid Emulsion

OBJECTIVES

Infants with intestinal failure have an increased risk of intestinal failure-associated liver disease (IFALD). Composite intravenous lipid emulsion (ILE) may reduce the risk of cholestasis. The primary outcome was to compare IFALD rates in infants with intestinal failure, between those receiving a composite ILE versus soybean oil ILE. The secondary outcome compared growth between these 2 groups.

METHODS

At our 2 tertiary neonatal/pediatric hospitals, we identified all patients (≤1 year old) who received ≥6 weeks parenteral nutrition (PN) from 2010 to 2018. Data included liver and growth parameters. IFALD was defined as serum conjugated bilirubin (CB) >33 µmol/L (≥2 mg/dL). Nonparametric tests were used for all comparisons.

RESULTS

Fifty infants (35 composite ILE, 15 soybean oil ILE) were included. Those on composite ILE received PN for longer (10.1 vs 7.6 weeks; P = 0.001) and had higher baseline CB (29 vs 6.5 μmol/L; P = 0.001). No differences were found by 6 weeks (14.5 vs 5 μmol/L; P = 0.54) and by PN cessation (4 vs 4 μmol/L; P = 0.33). The proportion of patients with IFALD decreased from 54% to 20% for composite ILE, while stable given soybean oil ILE (7%). There were no differences in weight, length, or head circumference z scores ( P > 0.05).

CONCLUSIONS

In our institutions, over 8 years, chronic intestinal failure was rare. Composite ILE was the predominant lipid choice for infants who needed longer courses of PN or had developed cholestasis. Despite longer PN duration, and higher baseline CB, overall rates of IFALD decreased with composite ILE. Regardless of parenteral lipid used, there were no differences in growth.

Effects of mixed oil emulsion on short-term clinical outcomes in premature infants: A prospective, multicenter, randomized controlled trial

OBJECTIVE

This study compared the clinical effects of two different lipid emulsions in premature infants with gestational age < 32 weeks (VPI) or birth weight < 1500 g (VLBWI) to provide an evidence-based medicine basis for optimizing intravenous lipid emulsion.

METHODS

This was a prospective multicenter randomized controlled study. A total of 465 VPIs or VLBWIs, admitted to the neonatal intensive care unit of five tertiary hospitals in China from March 1, 2021 to December 31, 2021, were recruited. All subjects were randomly allocated into two groups, namely, medium-chain triglycerides/long-chain triglycerides (MCT/LCT) group (n = 231) and soybean oil, medium-chain triglycerides, olive oil, and fish oil (SMOF) group (n = 234). Clinical features, biochemical indexes, nutrition support therapy, and complications were analyzed and compared between the two groups.

RESULTS

No significant differences were found in perinatal data, hospitalization, parenteral and enteral nutrition support between the two groups (P > 0.05). Compared with the MCT/LCT group, the incidence of neonates with a peak value of total bilirubin (TB) > 5 mg/dL (84/231 [36.4% vs. 60/234 [25.6%]), a peak value of direct bilirubin (DB) ≥ 2 mg/dL (26/231 [11.3% vs. 14/234 [6.0%]), a peak value of alkaline phosphatase (ALP) > 900 IU/L (17/231 [7.4% vs. 7/234 [3.0%]), and a peak value of triglycerides (TG) > 3.4 mmol/L (13/231 [5.6% vs. 4/234[1.7%]]) were lower in the SMOF group (P < 0.05). Univariate analysis showed that in the subgroup analysis of < 28 weeks, the incidence of parenteral nutrition-associated cholestasis (PNAC) and metabolic bone disease of prematurity (MBDP) were lower in the SMOF group (P = 0.043 and 0.029, respectively), whereas no significant differences were present in the incidence of PNAC and MBDP between the two groups at > 28 weeks group (P = 0.177 and 0.991, respectively). Multivariate logistic regression analysis revealed that the incidence of PNAC (aRR: 0.38, 95% confidence interval [CI]: 0.20-0.70, P = 0.002) and MBDP (aRR: 0.12, 95% CI: 0.19-0.81, P = 0.029) in the SMOF group were lower than that in the MCT/LCT group. In addition, no significant differences were recorded in the incidence of patent ductus arteriosus, feeding intolerance, necrotizing enterocolitis (Bell's stage ≥ 2), late-onset sepsis, bronchopulmonary dysplasia, intraventricular hemorrhage, periventricular leukomalacia, retinopathy of prematurity and extrauterine growth retardation between the two groups (P > 0.05).

CONCLUSIONS

The application of mixed oil emulsion in VPI or VLBWI can reduce the risk of plasma TB > 5 mg/dL, DB ≥ 2 mg/dL, ALP > 900 IU/L, and TG > 3.4 mmol/L during hospitalization. SMOF has better lipid tolerance, reduces the incidence of PNAC and MBDP, and exerts more benefits in preterm infants with gestational age < 28 weeks.

Retinopathy of prematurity: A review of pathophysiology and signaling pathways

Retinopathy of prematurity (ROP) is a vasoproliferative disorder of the retina and a leading cause of visual impairment and childhood blindness worldwide. The disease is characterized by an early stage of retinal microvascular degeneration, followed by neovascularization that can lead to subsequent retinal detachment and permanent visual loss. Several factors play a key role during the different pathological stages of the disease. Oxidative and nitrosative stress and inflammatory processes are important contributors to the early stage of ROP. Nitric oxide synthase and arginase play important roles in ischemia/reperfusion-induced neurovascular degeneration. Destructive neovascularization is driven by mediators of the hypoxia-inducible factor pathway, such as vascular endothelial growth factor and metabolic factors (succinate). The extracellular matrix is involved in hypoxia-induced retinal neovascularization. Vasorepulsive molecules (semaphorin 3A) intervene preventing the revascularization of the avascular zone. This review focuses on current concepts about signaling pathways and their mediators, involved in the pathogenesis of ROP, highlighting new potentially preventive and therapeutic modalities. A better understanding of the intricate molecular mechanisms underlying the pathogenesis of ROP should allow the development of more effective and targeted therapeutic agents to reduce aberrant vasoproliferation and facilitate physiological retinal vascular development.

Lipid strategies to prevent intestinal failure-associated liver disease in neonates: A pilot trial

BACKGROUND

Intestinal failure-associated liver disease (IFALD) occurs in up to 50% of neonates treated with prolonged parenteral nutrition. Preventative strategies for IFALD include soybean oil lipid emulsion (SOLE) minimization and use of mixed-oil intravenous lipid emulsions (ILE). We conducted a pilot study prospectively comparing these two ILE strategies in the prevention of IFALD in neonates who required abdominal surgery.

METHODS

We randomized eligible neonates to SOLE at 1 g/kg/day (SOLE Min) or mixed-oil ILE containing fish oil (MOLE) at 3 g/kg/day. These treatment groups were also compared with historic controls who received SOLE at 2-3 g/kg/day (SOLE Historic). We defined IFALD as a direct bilirubin >2 mg/dl on two measurements. Secondary outcomes included laboratory, growth, clinical, and nutrition outcomes.

RESULTS

A total of 24 prospective and 24 historic patients were included. There was no difference in the rate of IFALD. However, there was a difference in the weekly change of direct bilirubin levels (SOLE Historic +0.293 mg/dl/week vs MOLE, P < 0.001; SOLE Min +0.242 mg/dl/week vs MOLE, P < 0.001). The MOLE group also had a lower direct bilirubin at study completion (SOLE Historic, 1.7 ± 1.7 mg/dl; SOLE Min, 1.6 ± 1.4 mg/dl; MOLE, 0.4 ± 0.4 mg/dl; P = 0.002) and received greater total calories (P = 0.008).

CONCLUSION

The rate of IFALD did not differ when comparing ILE strategies in neonates requiring abdominal surgery. However, the MOLE group maintained significantly lower direct bilirubin levels over time while receiving increased calories. This pilot study highlights the need for further randomized controlled trials comparing these ILE strategies.

Erythrocyte Membrane Docosahexaenoic Acid (DHA) and Lipid Profile in Preterm Infants at Birth and Over the First Month of Life: A Comparative Study with Infants at Term

An observational comparative study was designed to assess the fatty acids profile in erythrocyte membrane phospholipids of 30 preterm neonates (<32 weeks gestation) at birth and after 1 month of life versus a convenience sample of 10 infants born at term. The panel of fatty acids included the families and components of saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), and n-6 and n-3 polyunsaturated fatty acids (PUFAs) as well as enzyme activity indexes and fatty acids ratios. At birth, the comparison of fatty acid families between preterm and term neonates showed a significantly higher content of SFAs and n-6 PUFAs, and a significantly lower content of MUFAs and n-3 PUFAs in the preterm group. After 30 days of life, significantly higher levels of n-6 PUFAs and significantly lower levels of n-3 PUFAs among preterm neonates persisted. At 30 days of birth, n-6 PUFA/n-3 PUFA and arachidonic acid (ARA) ARA/DHA remained significantly elevated, and DHA sufficiency index significantly decreased in the preterm group. The pattern of n-3 PUFA deficiency at birth and sustained for the first month of life would support the need of milk banking fortified with DHA and the use of DHA supplementation in breastfeeding mothers.

Dysfunctional peroxisomal lipid metabolisms and their ocular manifestations

Retina is rich in lipids and dyslipidemia causes retinal dysfunction and eye diseases. In retina, lipids are not only important membrane component in cells and organelles but also fuel substrates for energy production. However, our current knowledge of lipid processing in the retina are very limited. Peroxisomes play a critical role in lipid homeostasis and genetic disorders with peroxisomal dysfunction have different types of ocular complications. In this review, we focus on the role of peroxisomes in lipid metabolism, including degradation and detoxification of very-long-chain fatty acids, branched-chain fatty acids, dicarboxylic acids, reactive oxygen/nitrogen species, glyoxylate, and amino acids, as well as biosynthesis of docosahexaenoic acid, plasmalogen and bile acids. We also discuss the potential contributions of peroxisomal pathways to eye health and summarize the reported cases of ocular symptoms in patients with peroxisomal disorders, corresponding to each disrupted peroxisomal pathway. We also review the cross-talk between peroxisomes and other organelles such as lysosomes, endoplasmic reticulum and mitochondria.

Omega-3/Omega-6 Long-Chain Fatty Acid Imbalance in Phase I Retinopathy of Prematurity

There is a gap in understanding the effect of the essential ω-3 and ω-6 long-chain polyunsaturated fatty acids (LCPUFA) on Phase I retinopathy of prematurity (ROP), which precipitates proliferative ROP. Postnatal hyperglycemia contributes to Phase I ROP by delaying retinal vascularization. In mouse neonates with hyperglycemia-associated Phase I retinopathy, dietary ω-3 (vs. ω-6 LCPUFA) supplementation promoted retinal vessel development. However, ω-6 (vs. ω-3 LCPUFA) was also developmentally essential, promoting neuronal growth and metabolism as suggested by a strong metabolic shift in almost all types of retinal neuronal and glial cells identified with single-cell transcriptomics. Loss of adiponectin (APN) in mice (mimicking the low APN levels in Phase I ROP) decreased LCPUFA levels (including ω-3 and ω-6) in retinas under normoglycemic and hyperglycemic conditions. ω-3 (vs. ω-6) LCPUFA activated the APN pathway by increasing the circulating APN levels and inducing expression of the retinal APN receptor. Our findings suggested that both ω-3 and ω-6 LCPUFA are crucial in protecting against retinal neurovascular dysfunction in a Phase I ROP model; adequate ω-6 LCPUFA levels must be maintained in addition to ω-3 supplementation to prevent retinopathy. Activation of the APN pathway may further enhance the ω-3 and ω-6 LCPUFA's protection against ROP.

Fish oil-containing lipid emulsions prevention on parenteral nutrition-associated cholestasis in very low birth weight infants: a meta-analysis

BACKGROUND

The effect of fish oil-containing lipid emulsions on preventing parenteral nutrition-associated cholestasis (PNAC) in very low birth weight (VLBW) infants is not known. Thus, we conducted a meta-analysis to identify any prevention effect.

METHODS

PubMed, EMBASE, and CENTRAL were searched up to 26 January 2021 for studies related to the preventive effect of fish oil-containing lipid emulsions and fish oil-free lipid emulsions on cholestasis in VLBW infants. Revman 5.3 was used to synthesize the results. A fixed-effect model was used to summarize the data when the heterogeneity was non-significant (I² < 50%), and a random-effects model was used when the heterogeneity was significant (I² > 50%).

RESULTS

Of 728 articles, 11 randomized controlled trials met the inclusion criteria. The meta-analysis indicated that fish oil-containing lipid emulsion reduced the occurrence of PNAC significantly with risk ratio (RR) = 0.53, 95% confidence interval (CI) 0.36-0.80, P = 0.002. The heterogeneity was non-significant with I² = 23%. Subgroup analysis based on parenteral nutrition duration and median birth weight was performed. The synthesis results for patients with parenteral nutrition duration exceeding 14 days revealed I² = 35% (P = 0.15) and pooled RR = 0.47, 95% CI 0.30-0.73, P = 0.0008; and for patients with duration less than 14 days revealed I² = 0% (P = 0.72) and pooled RR = 1.14, 95% CI 0.39-3.35, P = 0.81. The synthesis for patients with birth weight more than 1000 g revealed I² = 0% (P = 0.41) and pooled RR = 0.55, 95% CI 0.26-1.18, P = 0.12; and for patients with birth weight below 1000 g revealed I² = 44% (P = 0.11) and pooled RR = 0.53, 95% CI 0.33-0.85, P = 0.009.

CONCLUSIONS

The fish oil-containing lipid emulsion can reduce the occurrence of PNAC in VLBW infants based on the available original randomized controlled trial studies, especially for patients with parenteral nutrition duration exceeding 14 days and extremely low birth weight infants. Future studies should be performed before a definitive conclusion can be established.

A Mixed-Lipid Emulsion Containing Fish Oil for the Parenteral Nutrition of Preterm Infants: No Impact on Visual Neuronal Conduction

Fish oil is rich in omega-3 fatty acids and essential for neuronal myelination and maturation. The aim of this study was to investigate whether the use of a mixed-lipid emulsion composed of soybean oil, medium-chain triglycerides, olive oil, and fish oil (SMOF-LE) compared to a pure soybean oil-based lipid emulsion (S-LE) for parenteral nutrition had an impact on neuronal conduction in preterm infants. This study is a retrospective matched cohort study comparing preterm infants <1000 g who received SMOF-LE in comparison to S-LE for parenteral nutrition. Visual evoked potentials (VEPs) were assessed longitudinally from birth until discharge. The latencies of the evoked peaks N2 and P2 were analyzed. The analysis included 76 infants (SMOF-LE: n = 41 and S-LE: n = 35) with 344 VEP measurements (SMOF-LE: n= 191 and S-LE n = 153). Values of N2 and P2 were not significantly different between the SMOF-LE and S-LE groups. A possible better treatment effect in the SMOF-LE group was seen as a trend toward a shorter latency, indicating faster neural conduction at around term-equivalent age. Prospective trials and follow-up studies are necessary in order to evaluate the potential positive effect of SMOF-LE on neuronal conduction and visual pathway maturation.

Biochemical Parameters in Extremely Preterm Infants Receiving Mixed Lipid Emulsions

OBJECTIVE

A mixture of soybean, medium-chain triglycerides, olive, and fish oils (SMOF) contains higher α-tocopherol and n-3 polyunsaturated fatty acids and lower phytosterol content compared with conventional soybean oil lipid emulsions (SOLE). We sought to characterize plasma total fatty acid profiles (FAPs) and assess the tolerability of long-term SMOF therapy in extremely preterm infants.

METHODS

We retrospectively evaluated infants born <28 weeks gestational age who received at least 30 consecutive days of SMOF between July 2016 and June 2019. We evaluated monthly FAPs and biochemical tolerance to SMOF using direct bilirubin (DB) and triglyceride (TG) levels. Growth parameters were evaluated longitudinally until discharge.

RESULTS

Sixteen patients with median gestational age 24 weeks (IQR, 23-25 weeks) received SMOF for median 76 days (IQR, 52-130 days). Fourteen patients had necrotizing enterocolitis (NEC) requiring surgical intervention and 15 patients received SOLE for median 19 days (IQR, 14-26 days) prior to switching to SMOF. Median docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) levels were elevated, whereas the remaining fatty acid levels fell within reported reference ranges. There were no incidents of essential fatty acid deficiency (triene to tetraene ratio >0.2) or hypertriglyceridemia (TG >200 mg/dL) with a general downtrend in DB after the first month on SMOF. All growth Z-scores declined throughout hospital stay.

CONCLUSIONS

Infants who received SMOF had a more pronounced elevation in DHA than EPA, of which the clinical significance remains unknown. Growth Z-scores declined with SMOF but were confounded by a high prevalence of surgically treated NEC.

Parenteral lipid emulsions in the preterm infant: current issues and controversies

Parenteral lipid emulsions are a necessary component of nutrition for extremely low gestational age newborns until adequate levels of enteral intake are established. Historically, Intralipid, a 100% soybean oil emulsion, has filled this role. Newer multicomponent lipid emulsions containing a mixture of other oils, including olive oil and fish oil, are now available as options, although the regulatory approval for use in neonates varies worldwide. When dosed at currently published recommendations, each of these lipid emulsions meets total fat and energy requirements without a risk of essential fatty acid deficiency. Thus, when choosing which lipid emulsion to provide, the answer must be based on the metabolic differences induced as a result of these fatty acid-rich emulsions and whether the emulsions provide a health advantage or pose a health risk. The questions of induced fatty acid profiles, health benefit and health risk are discussed sequentially for multicomponent lipid emulsions. Despite the growing acceptance of multicomponent lipid emulsions, there is concern regarding changes in blood fatty acid levels and potential health risk without strong evidence of benefit. There remains no ideal parenteral lipid emulsion option for the preterm infant. Standardising future animal and human studies in lipid delivery with the inclusion of lipid metabolism data will iteratively provide answers to inform the optimal lipid emulsion for the preterm infant.

Metabolism in Retinopathy of Prematurity

Retinopathy of prematurity is defined as retinal abnormalities that occur during development as a consequence of disturbed oxygen conditions and nutrient supply after preterm birth. Both neuronal maturation and retinal vascularization are impaired, leading to the compensatory but uncontrolled retinal neovessel growth. Current therapeutic interventions target the hypoxia-induced neovessels but negatively impact retinal neurons and normal vessels. Emerging evidence suggests that metabolic disturbance is a significant and underexplored risk factor in the disease pathogenesis. Hyperglycemia and dyslipidemia correlate with the retinal neurovascular dysfunction in infants born prematurely. Nutritional and hormonal supplementation relieve metabolic stress and improve retinal maturation. Here we focus on the mechanisms through which metabolism is involved in preterm-birth-related retinal disorder from clinical and experimental investigations. We will review and discuss potential therapeutic targets through the restoration of metabolic responses to prevent disease development and progression.

Association of Docosahexaenoic Acid and Arachidonic Acid Serum Levels With Retinopathy of Prematurity in Preterm Infants

IMPORTANCE

Supplementing preterm infants with long-chain polyunsaturated fatty acids (LC-PUFA) has been inconsistent in reducing the severity and incidence of retinopathy of prematurity (ROP). Furthermore, few studies have measured the long-term serum lipid levels after supplementation.

OBJECTIVE

To assess whether ROP severity is associated with serum levels of LC-PUFA, especially docosahexaenoic acid (DHA) and arachidonic acid (AA), during the first 28 postnatal days.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study analyzed the Mega Donna Mega study, a randomized clinical trial that provided enteral fatty acid supplementation at 3 neonatal intensive care units in Sweden. Infants included in this cohort study were born at a gestational age of less than 28 weeks between December 20, 2016, and August 6, 2019.

MAIN OUTCOMES AND MEASURES

Severity of ROP was classified as no ROP, mild or moderate ROP (stage 1-2), or severe ROP (stage 3 and type 1). Serum phospholipid fatty acids were measured through gas chromatography-mass spectrometry. Ordinal logistic regression, with a description of unadjusted odds ratio (OR) as well as gestational age- and birth weight-adjusted ORs and 95% CIs, was used. Areas under the curve were used to calculate mean daily levels of fatty acids during postnatal days 1 to 28. Blood samples were obtained at the postnatal ages of 1, 3, 7, 14, and 28 days.

RESULTS

A total of 175 infants were included in analysis. Of these infants, 99 were boys (56.6%); the median (IQR) gestational age was 25 weeks 5 days (24 weeks 3 days to 26 weeks 6 days), and the median (IQR) birth weight was 785 (650-945) grams. A higher DHA proportion was seen in infants with no ROP compared with those with mild or moderate ROP or severe ROP (OR per 0.5-molar percentage increase, 0.49 [95% CI, 0.36-0.68]; gestational age- and birth weight-adjusted OR, 0.66 [95% CI, 0.46-0.93]). The corresponding adjusted OR for AA levels per 1-molar percentage increase was 0.83 (95% CI, 0.66-1.05). The association between DHA levels and ROP severity appeared only in infants with sufficient AA levels, suggesting that a mean daily minimum level of 7.8 to 8.3 molar percentage of AA was necessary for a detectable association between DHA level and less severe ROP.

CONCLUSIONS AND RELEVANCE

This cohort study found that higher mean daily serum levels of DHA during the first 28 postnatal days were associated with less severe ROP even after adjustment for known risk factors, but only in infants with sufficiently high AA levels. Further studies are needed to identify LC-PUFA supplementation strategies that may prevent ROP and other morbidities.

Mfsd2a overexpression alleviates vascular dysfunction in diabetic retinopathy

Diabetic retinopathy (DR) is one of the common complications in diabetic patients. Nowadays, VEGF pathway is subject to extensive research. However, about 27% of the patients have a poor visual outcome, with 50% still having edema after two years' treatment of diabetic macular edema (DME) with ranibizumab. Docosahexaenoic acid (DHA), the primary ω-3 long-chain polyunsaturated fatty acid (LC-PUFA), reduces abnormal neovascularization and alleviates neovascular eye diseases. A study reported that fish oil reduced the incidence of retinopathy of prematurity (ROP) by about 27.5% in preterm infants. Although ω-3 LC-PUFAs protects against pathological retinal neovascularization, the treatment effectiveness is low. It is interesting to investigate why DHA therapy fails in some patients. In human vitreous humor samples, we found that the ratio of DHA and DHA-derived metabolites to total fatty acids was higher in vitreous humor from DR patients than that from macular hole patients; however, the ratio of DHA metabolites to DHA and DHA-derived metabolites was lower in the diabetic vitreous humor. The expression of Mfsd2a, the LPC-DHA transporter, was reduced in the oxygen-induced retinopathy (OIR) model and streptozotocin (STZ) model. In vitro, Mfsd2a overexpression inhibited endothelial cell proliferation, migration and vesicular transcytosis. Moreover, Mfsd2a overexpression in combination with the DHA diet obviously reduced abnormal retinal neovascularization and vascular leakage, which is more effective than Mfsd2a overexpression alone. These results suggest that DHA therapy failure in some DR patients is linked to low expression of Mfsd2a, and the combination of Mfsd2a overexpression and DHA therapy may be an effective treatment.

Morbidity Outcomes of Very Low Birth Weight Neonates Receiving Parenteral Nutrition with Fish Oil Enriched Lipid Emulsion or Lipid Emulsion with Soybean Oil: An Observational Study

Intralipid (Fresenius Kabi) was the most commonly used lipid emulsion in parenteral nutrition (PN), with a 100% soybean oil composition, a low vitamin E content, and a ω-6: ω-3 ratio of 7:1. A recent alternative formulation is SMOFlipid (Fresenius Kabi), with a ω-6: ω-3 ratio of 5:2 and higher vitamin E content. A retrospective observational study was conducted to determine neonatal morbidity in very low birth weight (VLBW) premature infants during two periods: P1, when PN was based exclusively on Intralipid, and P2, when only SMOFlipid was supplied. In total, 170 VLBW neonates were analyzed, of whom 103 received PN for more than 6 days, 56 during P1, and 47 during P2. In both periods, the antenatal and neonatal characteristics of the cohort were comparable. In this analysis, the prevalence of associated comorbidities was determined. During P2, there were fewer cases of moderate to severe bronchopulmonary dysplasia (BPD) and of cholestasis, but more cases of late sepsis, mainly Staphylococcus epidermidis. No changes in the prevalence of other neonatal comorbidities were observed. We believe that the SMOFlipid used in PN could discreetly improve the prevalence of cholestasis or BPD.

Is intravenous fish oil associated with the neurodevelopment of extremely low birth weight preterm infants on parenteral nutrition?

BACKGROUND & AIMS

Preterm infants are at increased risk of long-term neurodevelopmental disabilities (NDD). Long chain n-3 fatty acids play a key role during the development of the central nervous system and some studies in preterm infants showed benefits of docosahexaenoic acid and arachidonic acid supplementation for visual and cognitive development. In recent years fish oil has been added to the fat blend of intravenous (IV) lipid emulsions (LE) but to date scanty data are available on neurodevelopmental outcome of preterm infants that received fish oil containing LE. We studied the effect of fish oil containing IV LE vs standard IV LE on neurodevelopment in a large cohort of preterm infants who received routine parenteral nutrition (PN) from birth.

METHODS

We retrospectively reviewed the neurodevelopmental outcome of 477 preterm infants (birth weight (BW): 400-1249 g and gestational age (GA) at birth: 24⁺⁰ - 35⁺⁶ weeks (W)) admitted to our NICU between Oct-2008 and June-2017, who received routine PN with different LE, with and without fish oil (IV-FO vs CNTR). We compared neurodevelopment at 2 years corrected age by the Bayley III development scale and the incidence of NDD.

RESULTS

Demographics, birth data and the incidence of the main clinical short-term outcomes of prematurity were similar in the two groups (IV-FO: n = 178, GA 197 ± 14 days, BW 931 ± 182 g; CNTR: n = 192, GA 198 ± 15 days, BW 944 ± 194 g). No differences were found in maternal demographics nor in parental education between the two groups. Cognitive score was not significantly different between IV-FO and CNTR (92 ± 15 vs 93 ± 13, p = 0.5). No differences were found in motor and language scores, and in the incidence of NDD in the two groups.

CONCLUSIONS

Contrary to our hypothesis, the use of fish oil containing LE in a large cohort of preterm infants on routine PN did not result in better neurodevelopment. Large randomized controlled trials powered for neurodevelopment are needed to clarify the impact of the widely used fish oil containing LE on neurodevelopment of preterm infants.

Impact of Parenteral Lipid Emulsion Components on Cholestatic Liver Disease in Neonates

Total parenteral nutrition (TPN) is a life-saving intervention for infants that are unable to feed by mouth. Infants that remain on TPN for extended periods of time are at risk for the development of liver injury in the form of parenteral nutrition associated cholestasis (PNAC). Current research suggests the lipid component of TPN is a factor in the development of PNAC. Most notably, the fatty acid composition, vitamin E concentration, and presence of phytosterols are believed key mediators of lipid emulsion driven PNAC development. New emulsions comprised of fish oil and medium chain triglycerides show promise for reducing the incidence of PNAC in infants. In this review we will cover the current clinical studies on the benefit of fish oil and medium chain triglyceride containing lipid emulsions on the development of PNAC, the current constituents of lipid emulsions that may modulate the prevalence of PNAC, and potential new supplements to TPN to further reduce the incidence of PNAC.

Lipid intensive drug therapy for sepsis pilot: A Bayesian phase I clinical trial

OBJECTIVES

Cholesterol may be protective in sepsis. Patients with early sepsis may have critically low cholesterol levels that are associated with poor outcomes. The study objective was to test the safety of a fish oil-containing lipid injectable emulsion for stabilizing early cholesterol levels in sepsis.

METHODS

Phase I Bayesian optimal interval design trial of adult patients with septic shock (Sequential Organ Failure Assessment score ≥4 or vasopressor dependence). Using sequential dose escalation, participants received 2 doses of 1.0 to 1.6 g/kg of lipid emulsion (Smoflipid 20% lipid emulsion) within 48 hours of enrollment. Cholesterol levels, function, and organ failure were assessed serially during the first 7 days of hospital admission.

MEASUREMENTS AND MAIN RESULTS

A total of 10 patients with septic shock were enrolled. One patient withdrew for social reasons. Another patient had an unrelated medical complication and received 1 drug dose. Of 9 patients, mean age was 58 years (SD 16), median Sequential Organ Failure Assessment was 8, and 28-day mortality was 30%. No serious adverse events related to lipid infusion occurred. The six occurrences of non-serious adverse events possibly related to lipid infusion included hyperglycemia (1), elevated triglycerides (3), anemia (1), and vascular access redness/pain (1) for all doses. The mean change in total cholesterol levels from enrollment was -7 (SD 16.6) at 48 hours and 14 (SD 25.2) at 7 days.

CONCLUSIONS

Fish oil-containing lipid emulsion administration during early septic shock was safe. Further studies are needed to assess effects on cholesterol levels, function, and organ failure.

CLINICAL TRIAL REGISTRATION

NCT03405870.

Administration of an Intravenous Fat Emulsion Enriched with Medium-Chain Triglyceride/ω-3 Fatty Acids is Beneficial Towards Anti-Inflammatory Related Fatty Acid Profile in Preterm Neonates: A Randomized, Double-Blind Clinical Trial

Intravenous administration of pure soybean oil emulsions high in linoleic acid may lead to inflammation and lipid peroxidation in preterm neonates. We aimed to investigate the effects of a medium-chain triglyceride (MCT)/ω-3 polyunsaturated fatty acid (PUFA)-enriched intravenous fat emulsion (IVFE) on plasma fatty acid (FA) profile and serum interleukin-6 (IL-6) in preterm neonates. In this double-blind randomized study, 92 preterm neonates (gestational age < 32 weeks, birth weight < 1500 g) were assigned to receive either MCT/ω-3 PUFA-enriched IVFE (Intervention Group) or soybean oil-based IVFE (Control Group). Levels of FAs were measured at baseline (day 0) and day 15 of parenteral nutrition with gas-chromatography mass-spectrometry. Serum IL-6 was measured with sandwich ELISA in 59 neonates. Plasma FAs changed significantly over time; the MCT/ω-3 PUFA-IVFE group showed higher ω-3 PUFAs (p = 0.031), eicosapentaenoic acid (p = 0.000), and oleic acid (p = 0.003), and lower ω-6/ω-3 PUFAs ratio (p = 0.001) and ω-6 PUFAs (p = 0.023) compared to control group. Linoleic acid was higher in the soybean oil (SO)-based IVFE arm compared to the MCT/ω-3 PUFAs-IVFE arm (p = 0.006). Both fat emulsion types decreased IL-6 compared to baseline, but changes were insignificant between groups. Administration of MCT/ω-3 PUFA-enriched IVFE in preterm neonates is beneficial in changing the FA profile consistent with attenuated inflammatory response.

A Randomized Trial of Parenteral Nutrition Using a Mixed Lipid Emulsion Containing Fish Oil in Infants of Extremely Low Birth Weight: Neurodevelopmental Outcome at 12 and 24 Months Corrected Age, A Secondary Outcome Analysis

OBJECTIVE

To examine whether parenteral nutrition using a mixed lipid emulsion containing fish oil improves the neurodevelopmental outcomes of extremely low birth weight infants.

STUDY DESIGN

The study is a secondary outcome analysis of a double-blind randomized trial of 230 extremely low birth weight infants performed at a single level IV neonatal care unit (Medical University Vienna; June 2012 to June 2015). Participants received either a mixed lipid emulsion composed of soybean oil, medium chain triglycerides, olive oil, and fish oil, or a soybean oil-based lipid emulsion for parenteral nutrition. Neurodevelopment of study participants was assessed at 12 and 24 months corrected age (August 2013 to October 2017) using the Bayley Scales of Infant-Toddler Development, third edition.

RESULTS

At discharge, 206 of the 230 study participants were eligible. At 12 and 24 months corrected age, 174 of 206 (85%) and 164 of 206 (80%) infants were evaluated. At 12 months, there was no significant difference in cognitive (mixed lipid: median, 95 [IQR, 85-101]; soybean oil: median, 95 [IQR, 85-100]; P = .71), language (mixed lipid: median, 86 [IQR, 77-94], soybean oil: median, 89 [IQR, 79-94]; P = .48), or motor scores (mixed lipid: median, 88 [IQR, 76-94], soybean oil: median, 88 [IQR, 79-94]; P = .69). At 24 months, there was again no significant difference in cognitive (mixed lipid: median, 95 [IQR, 80-105], soybean oil: median, 95 [IQR, 90-105]; P = .17), language (mixed lipid: median, 89 [IQR, 75-97], soybean oil 89 [IQR, 77-100]; P = .54), and motor scores (mixed lipid: median, 94 [IQR, 82-103], soybean oil: median, 94 [IQR, 85-103]; P = .53).

CONCLUSIONS

Parenteral nutrition using a mixed lipid emulsion containing fish oil did not improve neurodevelopment of extremely low birth weight infants at 12 and 24 months corrected age.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01585935.

New-generation intravenous fat emulsions and bronchopulmonary dysplasia in preterm infants: a systematic review and meta-analysis

BACKGROUND

Fat emulsion is an important component of parenteral nutrition in premature infants. However, intravenous fat emulsions (IVFE) was reported to be associated with some serious complications, such as bronchopulmonary dysplasia (BPD). Compared to conventional soybean oil-based IVFE, new-generation IVFE may protect against BPD but the results are conflicting.

METHODS

Relevant literatures search was conducted and the summary effect estimates of odds ratio (OR) and 95% confidence interval (CI) were calculated with fixed-effects models.

RESULTS

Of 22 studies involving 3781 infants were selected in this study and BPD was reported as part of the included studies. The pooled estimate for 13 studies, comparing administration of new-generation IVFE with conventional IVFE, indicated that new-generation IVFE was not associated with a reduced risk of BPD in preterm infants, compared with conventional IVFE (OR 0.96; 95% CI 0.80-1.14); the pooled estimate for 18 studies, comparing administration of fish oil-containing IVFE with non-fish oil IVFE, indicated that fish oil-containing IVFE has no protective effect against the occurrence of BPD in preterm infants (OR 0.88; 95% CI 0.71-1.08).

CONCLUSIONS

There is no evidence to support that the new-generation IVFEs could prevent the incidence of BPD or fish oil-containing IVFEs could show a beneficial effect to BPD in premature infants.

Intravenous lipid emulsions and liver function in adult chronic intestinal failure patients: Results after 5 y of home parenteral nutrition

OBJECTIVES

Intravenous lipid emulsions (ILE) are an essential component of parenteral nutrition (PN); however, pure soybean oil emulsion is considered a risk factor for intestinal failure-associated liver disease (IFALD). Limited data are available on the effect of different ILEs on the liver during long-term PN, and to our knowledge, no study has evaluated outcomes beyond 12 mo. Therefore, the aim of the present study was to assess the influence of mixed ILEs on liver function during long-term PN.

METHODS

A randomized, open-label clinical trial was performed at the Intestinal Failure Center in Skawina, Poland. Sixty-seven patients (35 F, 32 M; mean age, 53.2 years) receiving home parenteral nutrition (HPN) due to stable chronic intestinal failure (CIF) were randomized to receive one of the following three ILEs: medium/long-chain triacylglycerides (MCT/LCT), olive oil/soybean oil (OO/SO), or a combination of SO/MCT/OO/fish oil (FO) (SMOFlipid). Patients were followed for 5 y. Liver function was assessed clinically and with biochemical parameters (total bilirubin, serum glutamyl oxalate transaminase, serum glutamyl pyruvate transaminase, γ-glutamyl transpeptidase, and alkaline phosphatase) at baseline and after 24 and 60 mo.

RESULTS

The most common etiology for CIF was vascular, followed by Crohn's disease, surgical complications, and radiation enteritis. HPN was effective in improving nutritional status and was associated with low rates of catheter infections and clinical complications. No significant differences were observed between groups in median concentrations serum glutamyl oxalate transaminase, serum glutamyl pyruvate transaminase, γ-glutamyl transpeptidase, or alkaline phosphatase at 24 or 60 mo. A significant reduction in median bilirubin concentration was observed in the SMOFlipid group at 60 mo compared with baseline (6.8 umol/L; interquartile range, 5.2-8.5 versus 7.7 umol/L; interquartile range, 4.9-12.4; P = 0.0138).

CONCLUSIONS

Mixed ILEs are safe and effective for use in patients on long-term HPN. A multicomponent ILE with FO can provide additional benefits in terms of liver function during long-term HPN.

Incidence of Complications Associated with Parenteral Nutrition in Preterm Infants < 32 Weeks with a Mixed Oil Lipid Emulsion vs a Soybean Oil Lipid Emulsion in a Level IV Neonatal Intensive Care Unit

BACKGROUND

Parenteral nutrition (PN) is crucial for the improvement of long-term outcomes in very low birth weight (VLBW) neonates. Lipid injectable emulsions are a key component of PN, as they contain essential fatty acids and provide energy critical for brain growth. Prolonged administration increases risk of intestinal failure-associated liver disease, including cholestasis, and other complications.

METHODS

This is a retrospective, quasi-experimental cohort study of 215 VLBW neonates. The primary outcome was a change in direct bilirubin concentration. Secondary outcomes included change in total bilirubin concentration and incidences of cholestasis and other disease states associated with PN and prematurity. Cholestasis was defined as direct bilirubin ≥ 1.0 mg/dL with total bilirubin < 5.0 mg/dL or direct bilirubin > 20% of total bilirubin with total bilirubin > 5.0 mg/dL.

RESULTS

Change in direct bilirubin concentration was not different between groups. Incidence of cholestasis was not different between groups per charted diagnosis or per study definition. Non-stage-0 retinopathy of prematurity, bronchopulmonary dysplasia, sepsis, and necrotizing enterocolitis were all lower in the mixed oil lipid emulsion group, which remained significant after adjustment for differences in gestational age, birth weight, and PN duration.

CONCLUSIONS

Although mixed oil lipid emulsion was not found to be associated with a lower risk of cholestasis, it may decrease risks of other disease states associated with PN therapy.

Composite Lipid Emulsion for the Infant at Risk of Intestinal Failure-associated Liver Disease: The Canadian Perspective

Currently, in North America we are fortunate to have a number of available options for lipid emulsions to be used in the parenteral nutrition regimens for infants and children, including for long-term parenteral nutrition given intestinal failure. Neonates and infants in particular are at risk for intestinal failure-associated liver disease (IFALD). The choice of parenteral lipid emulsion will influence the risk and severity of IFALD. The purpose of this review is to discuss the rationale for the composite lipid emulsion SMOFlipid that includes soybean, medium-chain triglycerides, olive and fish oils for IFALD, with focus on the Canadian practice and experience.

Growth and Clinical Outcome in Very Low-Birth-Weight Infants After the Introduction of a Multicomponent Intravenous Lipid Emulsion

BACKGROUND

Very low-birth-weight (VLBW; birth weight < 1500 g) infants are often dependent on intravenous nutrition after birth. Conventional soy-based intravenous lipid emulsions (Soy LE) are associated with inflammatory and metabolic complications that may be harmful to preterm infants. Evidence to support any clinical benefit associated with newer multicomponent emulsions (Mixed LE), remains inconsistent and unsubstantiated in appropriate studies. This retrospective study aimed to determine whether growth and clinical outcomes differed between VLBW infants given Mixed LE vs Soy LE at Auckland City Hospital.

METHODS

Data were collected on nutrition, growth, and neonatal morbidities for the first 4 weeks after birth. Outcomes were compared between 2 lipid cohorts, Soy LE (February 2013 - August 2014) and Mixed LE (August 2014 - December 2015), using univariate and multivariate analysis.

RESULTS

207 infants (Soy LE, 105 vs Mixed LE, 102) were included in the study. Significantly fewer infants in the Mixed LE cohort developed any stage retinopathy of prematurity (Soy LE 59% vs Mixed LE 39%, P = .005) or intraventricular hemorrhage (Soy LE 27% vs Mixed LE 15%, P = .03) during their admission. Mixed LE was also associated with significantly lower mean (P = .01), minimum (P = .03), and maximum (P = .04) total bilirubin concentrations across the first 4 weeks after birth. There was no difference in growth velocity or weight, length, and head circumference z-score change.

CONCLUSION

SMOFlipid may represent a favorable alternative to conventional lipid emulsions in neonatal parenteral nutrition regimens; however, long-term effects should be further evaluated.

Oxygen saturation to fraction of inspired oxygen ratio in preterm infants on routine parenteral nutrition with conventional or fish oil containing lipid emulsions

INTRODUCTION

The benefits of intravenous (IV) fish oil (FO), as a source of n-3 long-chain polyunsaturated fatty acids, on lung growth in preterm infants, remain controversial.

AIM

To evaluate if IV FO improves lung growth in small preterm infants on routine parenteral nutrition (PN).

MATERIALS AND METHODS

We retrospectively reviewed prospectively collected data of preterm infants with a birth weight <1250 g who received routine PN from birth. We compared patients who received FO containing IV lipid emulsions with infants who received conventional emulsions (CNTR). The oxygen saturation (SpO₂ ) to a fraction of inspired oxygen (FiO₂ ) ratio (SFR) at 36 weeks (W) of gestation was chosen as the primary outcome variable to assess lung growth.

RESULTS

Four hundred and seventy-seven infants were studied: 240 received IV FO and 237 CNTR. While exposure to antenatal glucocorticoids was higher in IV FO group than in CNTR (95 vs 90%, P = .04), there were no differences in birth data, enteral and parenteral nutrition intakes, ventilator supports and drug therapies. The incidence of the most common complications of prematurity at 36 W was not different (bronchopulmonary dysplasia was 27 vs 21% in IV FO vs CNTR infants, P = .1). Weight gain from birth to 36 W was marginally, but significantly, higher (+0.5 g/kg/d, P = .03) in IV FO group vs CNTR. SFR increased from 32 W to 36 W in all study patients (P < .001). IV FO infants had significantly lower SpO₂ from 33 W to 35 W (P < .001) and lower (worse) SFR at 36 W (432 ± 57 vs 444 ± 51, P = .026) compared to CNTR.

CONCLUSION

Contrary to our hypothesis, the use of FO containing IV lipid emulsions for the routine PN of the preterm infant did not improve lung growth compared to the infants who received conventional IV lipid emulsions.

Combination Antioxidant/NSAID Therapies and Oral/Topical Ocular Delivery Modes for Prevention of Oxygen-Induced Retinopathy in a Rat Model

Given the complexity of oxygen-induced retinopathy (OIR), we tested the hypothesis that combination therapies and modes of administration would synergistically optimize efficacy for prevention of OIR. Newborn rats were exposed to neonatal intermittent hypoxia (IH) from the first day of life (P0) until P14 during which they received: (1) oral glutathione nanoparticles (nGSH) with topical ocular phosphate buffered saline (PBS); (2) nGSH with topical ocular Acuvail (ACV); (3) oral coenzyme Q10 (CoQ10) + ACV; (4) oral omega 3 polyunsaturated fatty acids (n-3 PUFAs) + ACV; (5) CoQ10 + n-3 PUFAs + PBS; or (6) CoQ10 + n-3 PUFAs + ACV. Treated groups raised in room air (RA) served as controls. At P14, pups were placed in RA with no treatment until P21. Retinal vascular pathology, ocular angiogenesis biomarkers, histopathology, and morphometry were determined. All combination treatments in IH resulted in the most beneficial retinal outcomes consistent with suppression of angiogenesis growth factors during reoxygenation/reperfusion and no significant adverse effects on somatic growth. nGSH + PBS also reversed IH-induced retinopathy, but had negative effects on growth. Simultaneously targeting oxidants, inflammation, and poor growth mitigates the damaging effects of neonatal IH on the developing retina. Therapeutic synergy with combination delivery methods enhance individual attributes and simultaneously target multiple pathways involved in complex diseases such as OIR.

Pediatric Smoflipid Therapy: Patient Response and Safety Concerns

BACKGROUND

Intestinal failure-associated liver disease (IFALD) occurs in ≤85% of neonates receiving prolonged parenteral nutrition. Strategies for treatment of IFALD include alternative lipid therapies, such as Smoflipid (Fresenius Kabi). In this study, we reviewed our institutional Smoflipid use, including predictors of patient response and safety concerns.

METHODS

This is a retrospective chart review of all pediatric patients who received Smoflipid therapy over a 2-year period at Riley Hospital for Children. Forty-two patients (89%) had cholestasis at the start of Smoflipid therapy and were included in group analysis. We compared patients based on response to Smoflipid therapy, identifying associations and predictors of patient response. We also documented patient safety concerns, including essential fatty acid deficiency (EFAD), rapid infusion, and compatibility/access issues.

RESULTS

Sixteen patients (38%) with cholestasis had resolution with Smoflipid. Those patients with resolution were older at initiation (58 vs 33.5 days; P = .010), treated with Smoflipid for longer (85.5 vs 41 days; P = .001), and had lower direct bilirubin at the start of Smoflipid therapy (3.7 vs 5.2 mg/dL; P = .035). We identified multiple safety concerns, including EFAD (54%), rapid infusion (17%), and missed doses (51%). No patient characteristics were found to correlate with Smofllpid therapy and diagnosis of EFAD.

CONCLUSION

In our patient population, Smoflipid therapy led to cholestasis resolution in patients with lower direct bilirubin or less-severe IFALD. Use of Smoflipid is also associated with significant safety concerns, and its use should be coupled with close monitoring in pediatric patients, particularly in neonates.

Parenteral Fish-Oil Lipid Emulsions in Retinopathy of Prematurity: A Retrospective Comparative Study

Purpose

To evaluate the effects of a fish oil-containing regimen on the severity of retinopathy of prematurity (ROP) in preterm infants.

Methods

In this retrospective, observational study, 82 preterm infants with documented retinal examinations were evaluated. Patients' demographic data, associated morbidities, the worst ROP zone, stage, and the presence of plus disease during the follow-up examinations, and the need for ROP treatment in the two groups were recorded and analyzed.

Results

Forty-three infants were treated with INTRAlipid®, and 39 infants were treated with 20% SMOFlipid. There were no differences in gestational age, birth weight, and associated morbidities between the two groups. No differences were observed among the two groups in their need for treatment (P = 0.51), ROP zones (P = 0.62), and plus disease (P = 0.38). Although no difference was seen in ROP stages between the groups (P = 0.41), in subgroup analysis, Stage 3 (severe ROP) occurred significantly lower in the SMOFlipid group (P = 0.04) and Stage 0 occurred significantly higher in the SMOFlipid-treated infants (P = 0.05).

Conclusions

This study showed no difference between the two groups regarding the need for the treatment. The lower prevalence of severe ROP in preterm infants receiving SMOFlipid emulsion was observed comparing to the INTRAlipid-treated infants.

New generation lipid emulsions increase brain DHA and improve body composition, but not short-term neurodevelopment in parenterally-fed preterm piglets

New generation, multicomponent parenteral lipid emulsions provide key fatty acids for brain growth and development, such as docosahexaenoic acid (DHA) and arachidonic acid (AA), yet the content may be suboptimal for preterm infants. Our aim was to test whether DHA and AA-enriched lipid emulsions would increase activity, growth, and neurodevelopment in preterm piglets and limit brain inflammation. Cesarean-delivered preterm pigs were given three weeks of either enteral preterm infant formula (ENT) or TPN with one of three parenteral lipid emulsions: Intralipid (IL), SMOFlipid (SMOF) or an experimental emulsion (EXP). Activity was continuously monitored and weekly blood sampling and behavioral field testing performed. At termination of the study, whole body and tissue metrics were collected. Neuronal density was assessed in sections of hippocampus (HC), thalamus, and cortex. Frontal cortex (FC) and HC tissue were assayed for fatty acid profiles and expression of genes of neuronal growth and inflammation. After 3 weeks of treatment, brain DHA content in SMOF, EXP and ENT pigs was higher (P < 0.01) in FC but not HC vs. IL pigs. There were no differences in brain weight or neuron density among treatment groups. Inflammatory cytokine TNFα and IL-1β expression in brain regions were increased in IL pigs (P < 0.05) compared to other groups. Overall growth velocity was similar among groups, but IL pigs had higher percent body fat and increased insulin resistance compared to other treatments (P < 0.05). ENT pigs spent more time in higher physical activity levels compared to all TPN groups, but there were no differences in exploratory behavior among groups. We conclude that a soybean oil emulsion increased select brain inflammatory cytokines and multicomponent lipid emulsions enriched with DHA and AA in parenteral lipids results in increased cortical DHA and improved body composition without affecting short term neurodevelopmental outcomes.

The evolving use of intravenous lipid emulsions in the neonatal intensive care unit

Parenteral nutrition and intravenous lipid emulsions are essential for promoting optimal nutrition in the neonatal intensive care unit. However, long-term use of a pure soybean lipid emulsion is associated with a liver disease known as intestinal failure associated liver disease. Over the past several years, the science of lipid emulsions has evolved with a focus on nutritional optimization and disease prevention. This review's purpose is to provide a general overview of the three main components of lipid emulsions, phytosterols, the antioxidant Vitamin E, and polyunsaturated fatty acids, and their contribution to health.

Hypertriglyceridemia and Intravenous Lipid Titration During Routine Parenteral Nutrition in Small Preterm Infants

OBJECTIVES

In case of hypertriglyceridemia (HiTG) during parenteral nutrition (PN), the 2018 European Society of Paediatric Gastroenterology, Hepatology and Nutrition guidelines recommend an intravenous (IV) lipid titration, but its consequences in small preterm infants are largely unknown. We compared macronutrient and energy intakes, growth, diseases associated with prematurity, and neurodevelopment in small preterm infants on PN who developed (cases) or did not develop HiTG (controls, CNTR).

METHODS

We retrospectively reviewed data of preterm infants with a birth weight (BW) <1250 g consecutively admitted to our neonatal intensive care unit (2004-2016) who received routine PN. HiTG infants were defined by at least 1 triglyceride (TG) measurement >250 mg/dL during the first 10 days of life. Patients with and without HiTG were match-paired for BW and gestational age.

RESULTS

A total of 658 infants were analyzed and 196 (30%) had HiTG. One hundred thirty-six HiTG patients were matched with 136 CNTR. In the first 10 days of life, IV lipid, non-protein energy and total energy intakes, but not IV amino acids and carbohydrates, were significantly lower in HiTG infants. We found no differences between groups in diseases associated with prematurity. Anthropometry at 36 weeks (W), anthropometry at 2-year (Y) corrected age (CA), and neurodevelopment at 2Y CA were not different.

CONCLUSIONS

Growth, diseases associated with prematurity, and neurodevelopment at 2Y CA in HiTG infants were similar to CNTR. This occurred despite a statistically significant albeit small reduction in IV lipid and non-protein energy intakes due to a strict TG monitoring and IV lipid titration at TG levels >250 mg/dL.

Association of Retinopathy of Prematurity With Low Levels of Arachidonic Acid: A Secondary Analysis of a Randomized Clinical Trial

Importance

Mice with oxygen-induced retinopathy fed matched diets except for ω-3 long-chain polyunsaturated fatty acids (LC-PUFAs) vs ω-6 LC-PUFAs demonstrate relative antiangiogenic and neuroprotective associations of ω-3 LC-PUFAs. However, supplementing preterm infants with LC-PUFAs has been inconsistent in reducing major preterm morbidities. However, few studies measured serum lipid levels after supplementation.

Objective

To examine the associated risk of retinopathy of prematurity (ROP) from the levels of circulating ω-3 and ω-6 LC-PUFAs.

Design, Setting, and Participants

This longitudinal clinical study was a further analysis of serum lipid levels from a randomized controlled trial cohort of 90 infants born at gestational age (GA) less than 28 weeks. From April 4, 2013, to September 22, 2015, cord blood samples, followed by venous blood samples, were obtained at birth and at 1, 7, 14, and 28 days after birth and then at postmenstrual age (PMA) 32, 36, and 40 weeks at the neonatal intensive care unit at Sahlgrenska University Hospital in Göteborg, Sweden.

Main Outcomes and Measures

Serum phospholipid fatty acids were transmethylated and measured by gas chromatography-mass spectrometry. Mann-Whitney test, logistic regression Spearman rank correlation, and receiver operating characteristic curve analysis were used to compare differences between infants with no ROP and infants who developed ROP.

Results

Serum levels from 78 infants (43 male [55%]; mean [SD] GA, 25.5 [1.4] weeks) with a known ROP outcome were evaluated. Lower area under the curve (AUC) of arachidonic acid (AA) (20:4 ω-6) was seen in infants with a later diagnosis of ROP compared with infants with no ROP in the first month of life (mean, 34.05 [95% CI, 32.10-36.00] vs 37.15 [95% CI, 34.85-39.46]; P < .05). In addition, lower levels of AA at 32 weeks' PMA were seen in infants with later severe ROP compared with in those without ROP (mean, 7.06 [95% CI, 6.60-7.52] vs 8.74 [95% CI, 7.80-9.67]; P < .001). In logistic modeling, low postnatal serum levels of AA and GA at birth identified with a sensitivity greater than 90% of infants who developed ROP.

Conclusions and Relevance

Low postnatal levels of the ω-6 LC-PUFAs (AA) are strongly associated with ROP development. Evaluating postnatal AA fraction after birth in addition to GA may be useful for ROP prediction.

Trial Registration

clinicaltrials.gov Identifier: NCT02760472.

Early Enteral Administration of a Complex Lipid Emulsion Supplement Prevents Postnatal Deficits in Docosahexaenoic and Arachidonic Acids and Increases Tissue Accretion of Lipophilic Nutrients in Preterm Piglets

BACKGROUND

Preterm delivery and current nutrition strategies result in deficiencies of critical long-chain fatty acids (FAs) and lipophilic nutrients, increasing the risk of preterm morbidities. We sought to determine the efficacy of preventing postnatal deficits in FAs and lipophilic nutrients using an enteral concentrated lipid supplement in preterm piglets.

METHODS

Preterm piglets were fed a baseline diet devoid of arachidonic acid (AA) and docosahexaenoic acid (DHA) and randomized to enteral supplementation as follows: (1) Intralipid (IL), (2) complex lipid supplement 1 (CLS1) with an AA:DHA ratio of 0.25, or (3) CLS2 with an AA:DHA ratio of 1.2. On day 8, plasma and tissue levels of FAs and lipophilic nutrients were measured and ileum histology performed.

RESULTS

Plasma DHA levels decreased in the IL group by day 2. In contrast, DHA increased by day 2 compared with birth levels in both CLS1 and CLS2 groups. The IL and CLS1 groups demonstrated a continued decline in AA levels during the 8-day protocol, whereas AA levels in the CLS2 group on day 8 were comparable to birth levels. Preserving AA levels in the CLS2 group was associated with greater ileal villus height and muscular layer thickness. Lipophilic nutrients were effectively absorbed in plasma and tissues.

CONCLUSIONS

Enteral administration of CLS1 and CLS2 demonstrated similar increases in DHA levels compared with birth levels. Only CLS2 maintained AA birth levels. Providing a concentrated complex lipid emulsion with an AA:DHA ratio > 1 is important in preventing postnatal AA deficits.

Effects of two different lipid emulsions on antioxidant status, lipid peroxidation and parenteral nutrition- related cholestasis in premature babies, a randomized-controlled study

BACKGROUND

Olive oil-soybean oil (OO/SO) based lipid emulsions (LE) lack ω-3 PUFAs eicosapentaenoic acid -EPA and docosahexaenoic acid- DHA, which have clinical benefits on inflammatory processes. Fish oil based LEs are good sources of DHA and EPA. Fish oil, MCT, Olive oil and Soya oil (FMOS) lipid is one of the fish oil containing LEs supplemented with high levels of α-tocopherol and lower levels of phytosterol compared to OO/SO lipid emulsions. We investigated the effects of OO/SO and FMOS lipid preparations on cholestasis, levels of antioxidant enzymes and lipid peroxidation.

METHODS

Preterm neonates ≤32 gestational weeks age and/or ≤1500 g were randomly assigned to receive either FMOS or OO/SO in the first day of life. Catalase, superoxide dismutase (SOD), glutathione peroxidase (GPx) and thiobarbituric acid reactive substances (TBARS) levels in the first day of life, 7th day of lipid use and 28th day of life were measured and cholestasis during parenteral nutrition was recorded.

RESULTS

34 and 33 patients were in FMOS and OO/SO lipid groups respectively. Although the TBARS levels were higher in the first day of life and 7^th day of LEs in OO/SO lipid group (p=0.014 and p=0.022), on the 28^th day of life TBARS level was similar and SOD level was higher (p=0.014) in OO/SO group. Cholestasis was significantly lower in FMOS lipid group (0% vs. 18.2%), (p=0.011) and neonates regained birth weight earlier (p=0.006). There was no significant difference in other morbidities.

CONCLUSIONS

FMOS and OO/SO lipid emulsions have similar effects on lipid peroxidation on 28th day of life and on morbidities in short term period except for cholestasis.

Lipid emulsions for parenterally fed preterm infants

BACKGROUND

Conventionally used soybean oil-based lipid emulsion (S-LE) have high polyunsaturated fatty acid (PUFA) content and phytosterols that may contribute to adverse effects in preterm infants. The newer lipid emulsions (LE) from different lipid sources are currently available for use in preterm infants.

OBJECTIVES

To compare the safety and efficacy of all LE for parenteral nutrition (PN) in preterm infants (less than 37 weeks' gestation) including preterm infants with surgical conditions or parenteral nutrition-associated liver disease (PNALD)/cholestasis using direct comparisons and pair-wise meta-analyses.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2018, Issue 5), MEDLINE (1946 to 18 June 2018), Embase (1974 to 18 July 2018), CINAHL (1982 to 18 June 2018), MIDRIS (1971 to 31 May 2018), conference proceedings, trial registries (ClinicalTrials.gov and WHO's Trials Registry and Platform), and reference lists of retrieved articles.

SELECTION CRITERIA

Randomised or quasi-randomised controlled studies in preterm infants with or without surgical conditions or PNALD within the first six months of life.

DATA COLLECTION AND ANALYSIS

Data collection and analysis conformed to the methods of Cochrane Neonatal. We used the GRADE approach to assess the quality of evidence for important outcomes in addition to reporting statistical significance of results.

MAIN RESULTS

We included 29 studies (n = 2037) in this review. LE were classified in three broad groups: 1. all fish oil-containing LE including pure fish oil-LE (F-LE) and multisource LE (e.g. medium-chain triglycerides (MCT)-olive-fish-soybean oil-LE (MOFS-LE), MCT-fish-soybean oil-LE (MFS-LE) and olive-fish-soybean oil-LE (OFS-LE); 2. conventional S-LE; 3. alternative-LE (e.g. MCT-soybean oil-LE (MS-LE), olive-soybean oil-LE and borage oil-based LE).We considered the following broad comparisons: fish oil LE versus non-fish oil LE; fish oil LE versus another fish oil LE; alternative-LE versus S-LE; alternative-LE versus another alternative-LE in preterm infants less than 37 weeks' gestation, preterm infants with surgical conditions and preterm infants with PNALD/cholestasis. Separate subgroup comparisons of each LE preparation were included within these broader groups.Most studies in preterm infants used PN for mean duration of four weeks or less and for longer duration in infants with cholestasis or surgical conditions.We defined the primary outcome of PNALD/cholestasis as conjugated bilirubin (Cbil) 2 mg/dL or greater and resolution of PNALD/cholestasis as Cbil less than 2 mg/dL. There was heterogeneity in definitions used by the included studies with Cbil cut-offs ranging from 17.1 μmol/L (1 mg/dL) up to 50 μmol/L (about 3 mg/dL).In preterm infants, meta-analysis found no evidence of a difference in the incidence of PNALD/cholestasis (Cbil cut-off: 2 mg/dl) between fish oil-LEs and all non-fish oil LEs (typical risk ratio (RR) 0.61, 95% confidence interval (CI) 0.24 to 1.56; typical risk difference (RD) -0.03, 95% CI -0.08 to 0.02; 4 studies; n = 328; low-quality evidence).We also considered an outcome allowing for any definition of PNALD (different Cbil cutoffs). In the meta-analysis for PNALD/cholestasis, using any definition and restricted to low or unclear risk of bias studies, there was no evidence of a difference between fish oil LE and all non-fish oil LE for incidence of cholestasis (typical RR 0.80, 95% CI 0.53 to 1.21; typical RD -0.02, 95% CI -0.05 to 0.02; 10 studies; n = 1024; low-quality evidence). There was no evidence of difference in subgroup meta-analyses of individual LE types in any comparison.In preterm infants with surgical conditions or cholestasis, there was only one small study each reporting no evidence of a difference in incidence or resolution of cholestasis respectively with use of a pure F-LE versus S-LE (using a Cbil cut-off of 2 mg/dL).In preterm infants with PNALD/cholestasis (using any definition), the meta-analysis showed significantly less cholestasis with the use of fish oil-LE compared to S-LE (typical RR 0.54, 95% CI 0.32 to 0.91; typical RD -0.39, 95% CI -0.65 to -0.12; number needed to treat for an additional beneficial outcome (NNTB) 3, 95% CI 2 to 9; 2 studies; n = 40; very low-quality evidence). However, this outcome had a very low number of participants from two small studies with methodological differences, one of which was terminated early, increasing the uncertainty about effect estimates.There were no differences between LE types in pair-wise meta-analyses for growth in preterm infants. There was paucity of studies in preterm infants with surgical conditions or cholestasis to perform meta-analyses for growth and most other outcomes.In the secondary outcomes for preterm infants, there was no difference between fish-oil LE and non-fish oil LE in meta-analysis for severe retinopathy of prematurity (ROP) (stage 3 or greater, or requiring surgery: typical RR 0.80, 95% CI 0.55 to 1.16; typical RD -0.03, 95% CI -0.07 to 0.02; 7 studies; n = 731; very low-quality evidence). There were no differences in the LE types in pair-wise meta-analyses for death, bronchopulmonary dysplasia (BPD), ventilation duration, patent ductus arteriosus, sepsis, necrotising enterocolitis, intraventricular haemorrhage, periventricular leukomalacia, jaundice, hyperglycaemia, hypertriglyceridaemia, intrahepatocellular lipid content and conjugated bilirubin levels in any comparison.In surgical infants, one study (n = 19) reported no differences in death, sepsis rates, Cbil and neurodevelopmental outcomes with pure F-LE versus S-LE.In infants with cholestasis, there were no evidence of differences in death or sepsis in meta-analyses between fish oil-LE and S-LE; (2 studies; n = 40; very low-quality evidence).

AUTHORS' CONCLUSIONS

In the current review, we did not find any particular LE with or without fish oil to be better than another LE in preterm infants for prevention of PNALD/cholestasis, growth, mortality, ROP, BPD and other neonatal outcomes.In preterm infants with surgical conditions or cholestasis, there is currently insufficient evidence from randomised studies to determine with any certainty if fish oil LEs offer advantage in prevention or resolution of cholestasis or in any other clinical outcome.Further research, with larger well-designed trials, is warranted to evaluate the ideal composition of LE in preterm infants and the role of fish oil-containing and other LEs in the prevention and resolution of PNALD, ROP and other clinical outcomes.