Assessing whether early attention of very preterm infants can be improved by an omega-3 long-chain polyunsaturated fatty acid intervention: a follow-up of a randomised controlled tria

Introduction Docosahexaenoic acid (DHA) accumulates in the frontal lobes (responsible for higher-order cognitive skills) of the fetal brain during the last trimester of pregnancy. Infants born preterm miss some of this in utero provision of DHA, and have an increased risk of suboptimal neurodevelopment. It is thought that supplementing infants born preterm with DHA may improve developmental outcomes. The aim of this follow-up is to determine whether DHA supplementation in infants born preterm can improve areas of the brain associated with frontal lobe function, namely attention and distractibility. Methods and analysis We will assess a subset of children from the N-3 (omega-3) Fatty Acids for Improvement in Respiratory Outcomes (N3RO) multicentre double-blind randomised controlled trial of DHA supplementation. Infants born <29 weeks’ completed gestation were randomised to receive an enteral emulsion containing 60 mg/kg/day of DHA or a control emulsion from within the first 3 days of enteral feeding until 36 weeks’ postmenstrual age. Children will undergo multiple measures of attention at 18 months’ corrected age. The primary outcome is the average time to be distracted when attention is focused on a toy. Secondary outcomes are other aspects of attention, and (where possible) an assessment of cognition, language and motor development with the Bayley Scales of Infant and Toddler Development, Third Edition. A minimum of 72 children will be assessed to ensure 85% power to detect an effect on the primary outcome. Families, and research personnel are blinded to group assignment. All analyses will be conducted according to the intentionto-treat principal. Ethics and dissemination All procedures were approved by the relevant institutional ethics committees prior to commencement of the study. Results will be disseminated in peer-reviewed journal publications and academic presentations. Trial registration number ACTRN12612000503820; Preresults

Neurodevelopmental outcomes at 7 years’ corrected age in preterm infants who were fed high-dose docosahexaenoic acid to term equivalent: a follow-up of a randomised controlled trial

This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work noncommercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http:// creativecommons.org/licenses/by-nc/4.0/OBJECTIVE: To determine if improvements in cognitive outcome detected at 18 months' corrected age (CA) in infants born <33 weeks' gestation receiving a high-docosahexaenoic acid (DHA) compared with standard-DHA diet were sustained in early childhood. DESIGN: Follow-up of a multicentre randomised controlled trial. Randomisation was stratified for sex, birth weight (<1250 vs ≥1250 g) and hospital. SETTING: Five Australian tertiary hospitals from 2008 to 2013. PARTICIPANTS: 626 of the 657 participants randomised between 2001 and 2005 were eligible to participate. INTERVENTIONS: High-DHA (≈1% total fatty acids) enteral feeds compared with standard-DHA (≈0.3% total fatty acids) from age 2-4 days until term CA. PRIMARY OUTCOME: Full Scale IQ of the Wechsler Abbreviated Scale of Intelligence (WASI) at 7 years CA. Prespecified subgroup analyses based on the randomisation strata (sex, birth weight) were conducted. RESULTS: 604 (92% of the 657 originally randomised) consented to participate (291 high-DHA, 313 standard-DHA). To address missing data in the 604 consenting participants (22 for primary outcome), multiple imputation was performed. The Full Scale IQ was not significantly different between groups (high-DHA 98.3, SD 14.0, standard-DHA 98.5, SD 14.9; mean difference adjusted for sex, birthweight strata and hospital -0.3, 95% CI -2.9 to 2.2; p=0.79). There were no significant differences in any secondary outcomes. In prespecified subgroup analyses, there was a significant sex by treatment interaction on measures of parent-reported executive function and behaviour. Scores were within the normal range but girls receiving the high-DHA diet scored significantly higher (poorer outcome) compared with girls receiving the standard-DHA diet. CONCLUSIONS: Supplementing the diets of preterm infants with a DHA dose of approximately 1% total fatty acids from days 2-4 until term CA showed no evidence of benefit at 7 years' CA. TRIAL REGISTRATION NUMBER: Australian New Zealand Clinical Trials Registry: ACTRN12606000327583

Plasmacytoid Dendritic Cells Sequester High Prion Titres at Early Stages of Prion Infection

In most transmissible spongiform encephalopathies prions accumulate in the lymphoreticular system (LRS) long before they are detectable in the central nervous system. While a considerable body of evidence showed that B lymphocytes and follicular dendritic cells play a major role in prion colonization of lymphoid organs, the contribution of various other cell types, including antigen-presenting cells, to the accumulation and the spread of prions in the LRS are not well understood. A comprehensive study to compare prion titers of candidate cell types has not been performed to date, mainly due to limitations in the scope of animal bioassays where prohibitively large numbers of mice would be required to obtain sufficiently accurate data. By taking advantage of quantitative in vitro prion determination and magnetic-activated cell sorting, we studied the kinetics of prion accumulation in various splenic cell types at early stages of prion infection. Robust estimates for infectious titers were obtained by statistical modelling using a generalized linear model. Whilst prions were detectable in B and T lymphocytes and in antigen-presenting cells like dendritic cells and macrophages, highest infectious titers were determined in two cell types that have previously not been associated with prion pathogenesis, plasmacytoid dendritic (pDC) and natural killer (NK) cells. At 30 days after infection, NK cells were more than twice, and pDCs about seven-fold, as infectious as lymphocytes respectively. This result was unexpected since, in accordance to previous reports prion protein, an obligate requirement for prion replication, was undetectable in pDCs. This underscores the importance of prion sequestration and dissemination by antigen-presenting cells which are among the first cells of the immune system to encounter pathogens. We furthermore report the first evidence for a release of prions from lymphocytes and DCs of scrapie-infected mice ex vivo, a process that is associated with a release of exosome-like membrane vesicles

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

A randomised controlled trial of DHA-rich fish oil supplementation during pregnancy and subsequent development of attention, working memory and inhibitory control in early childhood.

The last trimester of pregnancy is the period during which the fetal brain is growing at its greatest velocity, particularly the frontal lobes and hippocampus. This is also the peak period for the accumulation of omega-3 long chain polyunsaturated fatty acid (LCPUFA) docosahexaenoic acid (DHA) in neural tissues. The amount of DHA required by the fetus is thought to exceed the DHA intake of women of child-bearing age who consume a Western-style diet. This has led to the belief that maternal DHA supplementation during pregnancy will enhance child cognitive development in these populations. Cohort studies have supported this belief by linking intake of foods rich in DHA (primarily seafood) during pregnancy to enhanced child cognitive development. However, only randomised controlled trials (RCTs) can establish causality. In this thesis I report a comprehensive systematic review of the current RCTs of DHA supplementation during pregnancy (Chapter 1) using procedures described by the Cochrane collaboration and the PRISMA statement. Results of globalised standard assessments in the reviewed RCTs were compared in meta analyses. No effect of DHA supplementation was found in any age group, except in the 2-5 year-olds where the LCPUFA group was advantaged. A risk of bias assessment revealed that the majority of the trials were of poor quality, particularly those in which there was a finding of significance. Furthermore the majority of trials used standardised tests of global development or cognition. Fetal DHA availability is thought to primarily effect the frontal lobes and hippocampus, which are responsible for higher order cognitive skills known as Executive Functions (EFs). The global assessments used in the RCTs capture performance across multiple neural systems simultaneously and lack the sensitivity to detect development in specific areas of cognition. Thus, global tests may not be suitable for detecting subtle effects of DHA supplementation on neurodevelopment. There has been a call for nutrition researchers to use specialised measures of cognitive functions that are appropriate for assessing the specific neural systems thought to be effected by an intervention, rather than global measures. I addressed the need for a specialised measure of frontal lobe and hippocampus development in a RCT of DHA supplementation during pregnancy. The systematic review identified the DOMInO Trial as being a high-quality trial with a lower risk of bias compared with the other published RCTs. No one task can represent overall executive functioning abilities so I applied a range of specialised, age-appropriate assessments of EFs in two-year-old children. Attention, working memory (WM) and inhibitory control (IC) were the EFs selected for assessment in a subgroup of healthy, term-born toddlers (aged 27-months) from the DOMInO Trial. Two tests, the Attention Assessment involving three measures of attention, and the Working Memory and Inhibitory Control (WMIC) Assessment were identified from the developmental psychology literature. The Attention Assessment involved providing the child with toys to play with and measuring their attention (looking) to the toy(s) in three different scenarios; 1. the child had one toy to play with and their attention to the toy was measured in the absence of any competition for attention or distractions, 2. The child had five toys to play with and the number of times their attention switched between the toys competing for attention was measured, 3. The child had one toy to play with while a television in the periphery offered a distraction, and the time the child took to be distracted, from the toy, by the television was measured. The WMIC Assessment involved training a child to search for a hidden figurine in a specific location in a large box of lentils, and then hiding the figurine in an alternate location and delaying them from retrieving the figurine. Accuracy of searching for the figurine hidden in the alternate location was measured. There was no effect of supplementation on the primary outcomes; latency to be distracted during Focused attention (Attention Assessment), and accuracy of searching for a hidden figurine during Test Trials (WMIC Assessment). The majority of the secondary outcomes supported the findings of null effect in the primary outcomes. There was one outcome in which there was a possible benefit of supplementation, but the effect was small and is likely to be due to chance. I conducted a large number of comparisons (n=18 pre-specified) on a relatively small sample (n=~152 per task) which increases the risk of a Type I error (finding a difference that is the result of chance). Furthermore, no other benefit was shown in any other outcomes, primary, secondary or exploratory. Associations between cord plasma DHA and outcomes of the Attention and WMIC assessments were inconsistent, indicating no true association. Overall, the results of the two assessments I used suggest no effect of DHA supplementation during pregnancy on the cognitive development of healthy, otherwise well-nourished term-born children. The findings of the specialised attention and WMIC assessments used in my study support the findings of global tests used in other RCTs of DHA supplementation during pregnancy. Increasing fetal exposure to DHA may not enhance cognitive development because growth of the brain is protected during in-utero development. Maternal stores of DHA, up-regulation of DHA synthesis and preferential transfer of DHA across the placenta during pregnancy may protect neurological structures from suboptimal development so that greater fetal exposure to DHA does not enhance child cognitive development. Future research will be needed to determine whether specific at-risk sub-groups, such as children from pregnancies with placental insufficiency or who are growth restricted in utero, benefit from DHA supplementation during pregnancy.Thesis (Ph.D.) -- University of Adelaide, School of Paediatrics and Reproductive Health, 201

The Influence of Omega-3 Long-Chain Polyunsaturated Fatty Acid, Docosahexaenoic Acid, on Child Behavioral Functioning: A Review of Randomized Controlled Trials of DHA Supplementation in Pregnancy, the Neonatal Period and Infancy

This is a review of randomized controlled trials using docosahexaenoic acid (DHA) interventions in the first 1000 days of life with assessments of behavioral functioning in childhood. Electronic databases were searched for trials with a DHA intervention (compared with a placebo group that received no or less DHA) at any time to either women or infants during the first 1000 days, with a subsequent assessment of child behavior. There were 25 trials involving 10,320 mother&ndash;child pairs, and 71 assessments of behavior in 6867 of the children (66.5% of those originally enrolled). From the 71 assessments administered, there were 401 comparisons between a DHA group and a control group, with most reporting a null effect. There were no findings of a positive effect of DHA, and 23 instances where the DHA group had worse scores compared with the control group. There was limited evidence that DHA supplementation had any effect on behavioral development, although two of the largest trials with behavioral measures detected adverse effects. Future trials, and future follow-ups of existing trials, should make an effort to evaluate the effect of DHA intervention on behavioral functioning

New Methodologies for Conducting Maternal, Infant, and Child Nutrition Research in the Era of COVID-19

The severe acute respiratory syndrome coronavirus disease 2019 (COVID-19) outbreak rapidly became a worldwide pandemic in early 2020. In Australia, government-mandated restrictions on non-essential face-to-face contact in the healthcare setting have been crucial for limiting opportunities for COVID-19 transmission, but they have severely limited, and even halted, many research activities. Our institute’s research practices in the vulnerable populations of pregnant women and young infants needed to adapt in order to continue without exposing participants, or staff, to an increased risk of exposure to COVID-19. Here, we discuss our pre-and-post COVID-19 methods for conducting research regarding nutrition during pregnancy, infancy, and early childhood. We discuss modifications to study methods implemented to avoid face-to-face contact when identifying and recruiting potential participants, gaining informed consent, conducting appointments, and collecting outcome data, and the implications of these changes. The COVID-19 pandemic has required numerous changes to the conduct of research activities, but many of those modifications will be useful in post-COVID-19 research settings

Estimated Choline Intakes and Dietary Sources of Choline in Pregnant Australian Women

(1) Background: Despite the postulated importance of choline during pregnancy, little is known about the choline intake of Australians during pregnancy. In this study, we estimated dietary intakes of choline in early and late pregnancy, compared those intakes to recommendations, and investigated food sources of choline in a group of pregnant women in Australia. (2) Methods: 103 pregnant women enrolled in a randomized controlled trial. In early pregnancy (12–16 weeks gestation) and late pregnancy (36 weeks gestation), women completed a food frequency questionnaire designed to assess dietary intake over the previous month. (3) Results: Choline intakes and sources were similar in early and late pregnancy. Median choline intake in early pregnancy was 362 mg/day. Of the women, 39% and 25% had choline intakes above the Australian National Health and Medical Research Council (NHMRC) adequate intake (AI) of \u3e440 mg/day and the European Food Safety Authority (EFSA) AI of \u3e480 mg/day for choline in pregnancy, respectively. Eggs, red meat, nuts, legumes, and dairy accounted for 50% of choline intake, with eggs being the most significant contributor at 17%. (4) Conclusions: Few pregnant women in our study met the AI recommended by the NHMRC and EFSA. In Australia, choline intake in pregnancy may need to be improved, but further work to define choline requirements in pregnancy is required

Effect of Docosahexaenoic Acid (DHA) Supplementation of Preterm Infants on Growth, Body Composition, and Blood Pressure at 7-Years Corrected Age: Follow-Up of a Randomized Controlled Trial

Aim: To determine if supplementation of infants born Methods: Seven-year follow-up of an Australian multicenter randomized controlled trial in which 657 infants were fed high-DHA (≈1% total fatty acids) enteral feeds or standard-DHA (≈0.3% total fatty acids) from age 2–4 d until term CA. Seven-year CA outcomes were growth (weight, height), body composition (lean body mass, fat mass, waist, and hip circumference), and blood pressure. Results: There was no effect of high-DHA enteral feeds compared with standard-DHA on growth, body composition, and blood pressure at 7-year CA either overall or in subgroup analysis by sex. There was a significant interaction between high-DHA and birthweight strata on height at 7-y CA (p = 0.03). However, the post-hoc analyses by birthweight strata did not reach significance (p > 0.1). High-DHA group infants were more likely to be classified as obese (relative risk 1.6 (95% CI 1.0, 2.6); p = 0.05). Conclusions: DHA supplementation of premature infants did not affect growth, body composition, or blood pressure at 7-year CA overall by sex and birthweight strata. The finding of a higher risk of obesity in children who receive high-DHA needs to be interpreted with caution due to the small number of children classified as obese