Anti-reflux medication use in preterm infants.

BACKGROUND: Current recommendations do not support the use of anti-reflux medications to treat gastro-oesophageal reflux disease (GORD) among preterm infants. OBJECTIVE: To describe the prevalence of GORD and the use of anti-reflux medications amongst very preterm infants (<32 weeks' gestational age (GA)) in neonatal units in England and Wales. DESIGN: Retrospective cohort study using the National Neonatal Research Database. RESULTS: Among 58,108 infants [median GA (IQR) 29 (27-30) weeks], 15.8% (n = 9191) had a diagnosis of GORD and 36.9% (n = 12,446) received anti-reflux medications. Those who received anti-reflux medications were more preterm [GA, median (IQR): medications, 28 (26-30) vs. no medications, 30 (28-31); p < 0.001] and had lower birth weight [mean (SD): medications, 1124 g (354) vs. no medications, 1265 g (384); p < 0.001]. Most (57%, n = 12,224) received Gaviscon, or Histamine-2 Receptor Antagonist (H2RA) (56%, n = 11,959). Over time, prokinetic use has declined substantially, the use of H2RAs and Gaviscon has reduced although they continue to be used frequently, whilst the use of PPIs has increased. CONCLUSIONS: Anti-reflux medications are frequently prescribed in very preterm infants, despite evidence to suggest that they are not effective and may be harmful. Clear guidelines for diagnosing GORD and the use of anti-reflux medications are required to rationalise the pharmacological management of GORD in preterm infants. IMPACT: Anti-reflux medications are frequently prescribed, often without a diagnosis of gastro-oesophageal reflux disease, to very preterm infants while in the neonatal unit and at discharge. Half of the infants born at <28 weeks' gestational age receive anti-reflux medications in hospital and a quarter are discharged home on them. Although the use of prokinetics declined following alerts of adverse events, histamine2-receptor antagonists and alginates such as Gaviscon continue to be used and the use of proton-pump inhibitors has increased more than 2-fold.

Cold Exposure Drives Weight Gain and Adiposity following Chronic Suppression of Brown Adipose Tissue.

Therapeutic activation of thermogenic brown adipose tissue (BAT) may be feasible to prevent, or treat, cardiometabolic disease. However, rodents are commonly housed below thermoneutrality (~20 °C) which can modulate their metabolism and physiology including the hyperactivation of brown (BAT) and beige white adipose tissue. We housed animals at thermoneutrality from weaning to chronically supress BAT, mimic human physiology and explore the efficacy of chronic, mild cold exposure (20 °C) and ß3-adrenoreceptor agonism (YM-178) under these conditions. Using metabolic phenotyping and exploratory proteomics we show that transfer from 28 °C to 20 °C drives weight gain and a 125% increase in subcutaneous fat mass, an effect not seen with YM-178 administration, thus suggesting a direct effect of a cool ambient temperature in promoting weight gain and further adiposity in obese rats. Following chronic suppression of BAT, uncoupling protein 1 mRNA was undetectable in the subcutaneous inguinal white adipose tissue (IWAT) in all groups. Using exploratory adipose tissue proteomics, we reveal novel gene ontology terms associated with cold-induced weight gain in BAT and IWAT whilst Reactome pathway analysis highlights the regulation of mitotic (i.e., G2/M transition) and metabolism of amino acids and derivatives pathways. Conversely, YM-178 had minimal metabolic-related effects but modified pathways involved in proteolysis (i.e., eukaryotic translation initiation) and RNA surveillance across both tissues. Taken together these findings are indicative of a novel mechanism whereby animals increase body weight and fat mass following chronic suppression of adaptive thermogenesis from weaning. In addition, treatment with a B3-adrenoreceptor agonist did not improve metabolic health in obese animals raised at thermoneutrality.

Reduced brown adipose tissue-associated skin temperature following cold stimulation in children and adolescents with type 1 diabetes.

BACKGROUND: Brown adipose tissue (BAT) is essential to maintain body temperature. Its ability to convert chemical energy in glucose and free fatty acids to heat is conferred by a unique protein, UCP-1. BAT activity is greatest in children and adolescents, declining through adulthood. Blood glucose concentrations outside the normal nondiabetic range are common in type 1 diabetes and hyperglycaemia leads to insulin resistance in muscle and white adipose tissue, but whether this applies to BAT, is not known. METHOD: To investigate the effect of type 1 diabetes on BAT activity, we measured the supraclavicular temperature of 20 children with type 1 diabetes and compared them to 20 age-matched controls, using infrared thermography. RESULTS: The diabetes group had lower stimulated supraclavicular temperatures (diabetes group: 35.03 (34.76-35.30)°C; control group: 35.42 (35.16-35.69)°C; p = 0.037) and a reduced response in relative temperature following cold stimulation, after adjusting for BMI (diabetes group: 0.11 (0.03-0.18)°C; control group: 0.22 (0.15-0.29)°C; p = 0.034). In the diabetes group, there was no association between glycaemic measures and supraclavicular temperatures, but the method of insulin delivery may significantly affect the change in supraclavicular temperature with stimulation (injections: 0.01 (-0.07-0.09)°C; pump: 0.15 (0.04-0.26)°C; p = 0.028). CONCLUSIONS: While further work is needed to better understand the glucose-insulin-BAT relationship, one possible explanation for the reduced supraclavicular temperature is that exogenous, unlike endogenous, insulin, is not suppressed by the activity of the sympathetic nervous system, preventing lipolysis-driven activation of BAT.

Sexual Dimorphism of Brown Adipose Tissue Function.

OBJECTIVE: To determine whether brown adipose tissue (BAT) activity in school-age children differs between the sexes and to explore the impact of dietary intake, sedentary behavior, and picky/fussy eating. STUDY DESIGN: Children aged 8.5-11.8 years of age (n = 36) underwent infrared thermography to determine the temperature of the skin overlying the main superficial BAT depot in the supraclavicular region before and after 5 minutes of mild cold exposure (single-hand immersion in cool tap water at about 20°C). The relationships between the supraclavicular region temperature and parental reports of food consumption, eating behavior, and inactivity were explored. RESULTS: The supraclavicular region temperature was higher in boys (n = 16) at baseline, and after cold exposure. Boys displayed a greater thermogenic response to cold. Strong negative correlations were observed between the supraclavicular region temperature and body mass index percentile, and differences in supraclavicular region temperature between girls and boys persisted after adjustment for body mass index percentile. A negative linear relationship was observed between protein and vegetable intake and supraclavicular region temperature in girls only, but did not persist after adjustment for multiple comparisons. There was no difference in the adjusted supraclavicular region temperature between active or inactive children, or picky and nonpicky eaters. CONCLUSIONS: These findings indicate sexual dimorphism in BAT thermogenic activity and a sex-specific impact of diet. Future studies should aim to quantify the contribution of BAT to childhood energy expenditure, energy imbalance, and any role in the origins of childhood obesity.

Infrared Thermography.

Historically, brown adipose tissue has been elusive and not easy to detect, hence its relative obscurity in human physiology until its rediscovery in 2009. At that point, it was proven that the symmetrical artefacts frequently detected on positron emission tomography-computed tomography (PET-CT), which resolved if the environment was kept warm, were brown adipose tissue deposits. PET-CT has remained the stalwart of human brown adipose tissue research and is still considered the gold standard. However, PET-CT exposes the participant to ionising radiation, limiting studies to large, but retrospective, review of clinical imaging or a small-scale, but prospective, design. Within this context, alternative imaging modalities have been sought. Due to the heat-generating properties of brown adipose tissue, infrared thermography is a natural candidate for measuring its activity and the supraclavicular depot is relatively superficial, allowing detection of the heat signature. Infrared thermography is a non-invasive, non-contact technique for measuring temperature remotely. Recent developments in image analysis techniques have facilitated the use of infrared thermography to study brown adipose tissue activation in populations, and in ways, not previously feasible.

Tissue cell stress response to obesity and its interaction with late gestation diet.

Intrauterine growth restriction in late pregnancy can contribute to adverse long-term metabolic health in the offspring. In the present study we used an animal (sheep) model of maternal dietary manipulation in late pregnancy, combined with exposure of the offspring to a low-activity, obesogenic environment after weaning, to characterise the effects on glucose homeostasis. Dizygotic twin-pregnant sheep were either fed to 60% of requirements (nutrient restriction (R)) or fed ad libitum (~140% of requirements (A)) from 110 days gestation until term (~147 days). After weaning (~3 months of age), the offspring were kept in either a standard (in order to remain lean) or low-activity, obesogenic environment. R mothers gained less weight and produced smaller offspring. As adults, obese offspring were heavier and fatter with reduced glucose tolerance, regardless of maternal diet. Molecular markers of stress and autophagy in liver and adipose tissue were increased with obesity, with gene expression of hepatic glucose-related protein 78 (Grp78) and omental activation transcription factor 6 (Atf6), Grp78 and ER stress degradation enhancer molecule 1 (Edem1) only being increased in R offspring. In conclusion, the adverse effect of juvenile-onset obesity on insulin-responsive tissues can be amplified by previous exposure to a suboptimal nutritional environment in utero, thereby contributing to earlier onset of insulin resistance.

The Placenta, Maternal Diet and Adipose Tissue Development in the Newborn.

BACKGROUND: A majority of adipose tissue present in the newborn possess the unique mitochondrial protein, uncoupling protein (UCP1). It is thus highly metabolically active and capable of producing 300 times more heat per unit mass than any other organ in the body. The extent to which maternal obesity and/or an obesogenic diet impacts on placental function thereby resetting the relative distribution of different types of fat in the fetus is unknown. SUMMARY: Developmentally the majority (if not all) fat in the fetus can be considered as classical brown fat, in which UCP1 is highly abundant. In contrast, beige (or recruitable) fat which possess 90% less UCP1 may only appear after birth, as a majority of fat depots undergo a pronounced transformation that is usually accompanied by the loss of UCP1. The extent to which this process can be modulated in a depot-specific manner and/or changes in the maternal metabolic environment remain unknown. Key Messages: An increased understanding of the mechanism by which offspring born to mothers possess excessive adipose tissue could enable sustainable interventions designed to promote the abundance of UCP1 possessing adipocytes. Ultimately, this would increase their energy expenditure and improve glucose homeostasis in these individuals.

The Ontogeny of Brown Adipose Tissue.

There are three different types of adipose tissue (AT)-brown, white, and beige-that differ with stage of development, species, and anatomical location. Of these, brown AT (BAT) is the least abundant but has the greatest potential impact on energy balance. BAT is capable of rapidly producing large amounts of heat through activation of the unique uncoupling protein 1 (UCP1) located within the inner mitochondrial membrane. White AT is an endocrine organ and site of lipid storage, whereas beige AT is primarily white but contains some cells that possess UCP1. BAT first appears in the fetus around mid-gestation and is then gradually lost through childhood, adolescence, and adulthood. We focus on the interrelationships between adipocyte classification, anatomical location, and impact of diet in early life together with the extent to which fat development differs between the major species examined. Ultimately, novel dietary interventions designed to reactivate BAT could be possible.

Brown adipose tissue activation as measured by infrared thermography by mild anticipatory psychological stress in lean healthy females.

NEW FINDINGS: What is the central question of this study? Does psychological stress, which is known to promote cortisol secretion, simultaneously activate brown adipose tissue function in healthy adult females? What is the main finding and its importance? One explanation for the pronounced differences in brown adipose tissue function between individuals lies in their responsiveness to psychological stress and, as such, should be taken into account when examining its in vivo stimulation. Brown adipose tissue (BAT) has been implicated in the pathogenesis of obesity, type 2 diabetes and the metabolic syndrome and is a potential therapeutic target. Brown adipose tissue can have a significant impact on energy balance and glucose homeostasis through the action of uncoupling protein 1, dissipating chemical energy as heat following neuroendocrine stimulation. We hypothesized that psychological stress, which is known to promote cortisol secretion, would simultaneously activate BAT at thermoneutrality. Brown adipose tissue activity was measured using infrared thermography to determine changes in the temperature of the skin overlying supraclavicular BAT (TSCR ). A mild psychological stress was induced in five healthy, lean, female, Caucasian volunteers using a short mental arithmetic (MA) test. The TSCR was compared with a repeated assessment, in which the MA test was replaced with a period of relaxation. Although MA did not elicit an acute stress response, anticipation of MA testing led to an increase in salivary cortisol, indicative of an anticipatory stress response, that was associated with a trend towards higher absolute and relative TSCR . A positive correlation between TSCR and cortisol was found during the anticipatory phase, a relationship that was enhanced by increased cortisol linked to MA. Our findings suggest that subtle changes in the level of psychological stress can stimulate BAT, findings that may account for the high variability and inconsistency in reported BAT prevalence and activity measured by other modalities. Consistent assessment of this uniquely metabolic tissue is fundamental to the discovery of potential therapeutic strategies against metabolic disease.

High fructose consumption in pregnancy alters the perinatal environment without increasing metabolic disease in the offspring.

Maternal carbohydrate intake is one important determinant of fetal body composition, but whether increased exposure to individual sugars has long-term adverse effects on the offspring is not well established. Therefore, we examined the effect of fructose feeding on the mother, placenta, fetus and her offspring up to 6 months of life when they had been weaned onto a standard rodent diet and not exposed to additional fructose. Dams fed fructose were fatter, had raised plasma insulin and triglycerides from mid-gestation and higher glucose near term. Maternal resistance arteries showed changes in function that could negatively affect regulation of blood pressure and tissue perfusion in the mother and development of the fetus. Fructose feeding had no effect on placental weight or fetal metabolic profiles, but placental gene expression for the glucose transporter GLUT1 was reduced, whereas the abundance of sodium-dependent neutral amino acid transporter-2 was raised. Offspring born to fructose-fed and control dams were similar at birth and had similar post-weaning growth rates, and neither fat mass nor metabolic profiles were affected. In conclusion, raised fructose consumption during reproduction results in pronounced maternal metabolic and vascular effects, but no major detrimental metabolic effects were observed in offspring up to 6 months of age.

Suboptimal maternal nutrition during early-to-mid gestation in the sheep enhances pericardial adiposity in the near-term fetus.

Manipulation of the maternal diet at defined stages of gestation influences long-term health by inducing changes in fetal adipose tissue development, characterised as possessing brown and white adipocytes. We determined whether suboptimal maternal nutrition in early-to-mid gestation, followed by ad libitum feeding until term, increases adiposity in the pericardial depot of the sheep fetus. Pericardial adipose tissue was sampled from near-term (140 days) fetuses delivered to mothers fed either 100% (C) or 60% (i.e. nutrient restricted (NR)) of their total metabolisable requirements from 28 to 80 days gestation and then fed ad libitum. Adipose tissue mass, uncoupling protein (UCP) 1 and gene expression of brown and white adipogenic genes was measured. Total visceral and pericardial adiposity was increased in offspring born to NR mothers. The abundance of UCP1 was increased, together with those genes involved in brown (e.g. BMP7 and C/EBPß) and white (e.g. BMP4 and C/EBPα) adipogenesis, whereas insulin receptor gene expression was downregulated. In conclusion, suboptimal maternal nutrition between early-to-mid gestation followed by ad libitum feeding enhances pericardial adiposity near to term. A combination of raised UCP1 and adipose tissue mass could improve survival following cold exposure at birth. In the longer term, this enhanced adipogenic potential could predispose to greater pericardial adiposity.

A healthy nation: strengthening child health research in the UK.

Despite a general acknowledgment that research in children is necessary and ethical, the evidence base for child-specific treatments is still sparse. We investigated children's biomedical and health services research in the UK in relation to training, infrastructure and activity, research evidence, and visibility. We show that excellent opportunities for career researchers exist through a competitive, national integrated academic training programme, but that the number of academic paediatricians has decreased by 18% between 2000 and 2011, falling from 11·3% to 5·9% of the consultant workforce. The potential for rapid delivery of studies in children through the National Health Service (NHS) is not being realised: clinical trainees are poorly equipped with core research skills; most newly appointed consultant paediatricians have little or no research experience; less than 5% of contracted consultant time supports research; less than 2·5% of the 2 million children seen in the NHS every year are recruited to studies; and ten of the 20 UK children's hospitals do not have a clinical research facility. Support through National Institute for Health Research networks is good for studies into drugs, but inconsistent for non-drug research; less than 5% of registered studies involve children and only one children's biomedical research centre has been allocated funding from 2012. Of the UK annual public and charitable biomedical research expenditure of roughly £2·2 billion, about 5% is directed at child health research. The scant evidence base is impeding the development of clinical guidance and policy-less than 20% of the outputs of the National Institute for Health and Clinical Excellence are applicable to children. Paediatric representation on major research boards is weak. Parent and young people's advocacy is fragmented, and their views are insufficiently heeded by regulatory bodies. The strong UK Government commitment to biomedical research has not been translated fully to research for children. The power of research in children to turn the tide of the growing burden of non-communicable, chronic, adult diseases that have their origins in early life, to benefit the health of an ageing population and future generations, and to reduce health-care costs is inadequately recognised. On the basis of our findings, we make several recommendations to improve early-years research, including the formation of multidisciplinary, cross-institutional groups of clinical and non-clinical child health researchers and their access to diagnostic and laboratory facilities suitable for children; a unified Children's Research Network for drug studies and non-drug studies; regulatory assessment of research that is proportionate and based on consistent national criteria; an expansion of research posts; support for parents' and young people's advocacy; collaboration between children's research charities; improved research training for paediatric trainees; and closer integration of child health research with core NHS activities.

Body mass index as a determinant of brown adipose tissue function in healthy children.

OBJECTIVE: To determine whether body mass index (BMI) percentile and ethnicity influence skin temperature overlying brown adipose tissue (BAT) depots in the supraclavicular region in healthy children. STUDY DESIGN: Infrared thermography measured supraclavicular region temperature (T(SCR)) at baseline and after exposure to a mild cool stimulus (single hand immersion in water at 20.1 °C) for 5 minutes in children aged 6-11 years (n = 55). The studies were undertaken in a normal school environment. RESULTS: BMI percentile and ethnicity were significant predictors of baseline T(SCR), with an inverse relationship between BMI percentile persisting after adjustment for ethnicity. Twenty-four children demonstrated a significant rise in T(SCR) after exposure to the cool stimulus. BMI percentile was a significant predictor of T(SCR) response, although there was no effect of ethnicity on T(SCR) change after exposure to the cool stimulus. CONCLUSION: We have demonstrated a negative relationship between BMI percentile and both baseline T(SCR), colocating with the primary region of BAT, and the change in T(SCR) in response to the cool stimulus. Future studies aimed at determining the primary factors regulating BAT function in healthy children should be targeted at the goal of maintaining a healthy BMI trajectory during childhood.

Epigenetics and obesity: a relationship waiting to be explained.

Obesity can have multifactorial causes that may change with development and are not simply attributable to one's genetic constitution. To date, expensive and laborious genome-wide association studies have only ascribed a small contribution of genetic variants to obesity. The emergence of the field of epigenetics now offers a new paradigm with which to study excess fat mass. Currently, however, there are no compelling epigenetic studies to explain the role of epigenetics in obesity, especially from a developmental perspective. It is clear that until there are advances in the understanding of the main mechanisms by which different fat types, i.e. brown, beige, and white, are established and how these differ between depots and species, population-based studies designed to determine specific aspects of epigenetics will be potentially limited. Obesity is a slowly evolving condition that is not simply explained by changes in the intake of one macronutrient. The latest advances in epigenetics, coupled with the establishment of relevant longitudinal models of obesity, which incorporate functionally relevant end points, may now permit the precise contribution of epigenetic modifications to excess fat mass to be effectively studied.

Effects of implementation of a care bundle on rates of necrotising enterocolitis and own mother's milk feeding in the East Midlands: protocol for a mixed methods impact and process evaluation study.

INTRODUCTION: Prevention of necrotising enterocolitis (NEC) is vital for improving neonatal outcomes. Feeding own mother's milk helps prevent NEC. Rates of own mother's milk feeding in the East Midlands are lower than the national average and the incidence of NEC is higher. The East Midlands Neonatal Operational Delivery Network (EMNODN) has created a care bundle to improve these in babies born at <32 weeks' gestation, the group at the highest risk of NEC. The bundle was introduced in September 2022 and embedded by December 2022. We will evaluate its effectiveness and conduct a process evaluation to understand barriers and facilitators to implementation. METHODS AND ANALYSIS: We will conduct a retrospective cohort study (workstream 1) using data from the National Neonatal Research Database (NNRD). We will identify infants receiving any own mother's milk on day 14 and at discharge, and cases of severe NEC. We will aggregate outcomes by birth month and use interrupted time series analysis to estimate an incidence rate ratio for changes after the care bundle was embedded, relative to pre-implementation. We will model data from all other NNRD units and assess whether there are any concurrent changes to exclude confounding due to other events.We will apply the RE-AIM framework (workstream 2), supplemented by the Consolidated Framework for Implementation Research and Framework for Implementation Fidelity, to conduct a mixed methods evaluation in EMNODN units. We will triangulate data from several sources, including questionnaires and semistructured interviews with parents and healthcare professionals, and data from patient records. ETHICS AND DISSEMINATION: The study has approval from the South East Scotland Research Ethics Committee 01 and the Health Research Authority and Health and Care Research Wales (IRAS 323099). Results will be disseminated via scientific journals and conferences, to neonatal service commissioners and through public-facing infographics. TRIAL REGISTRATION NUMBER: NCT05934123.

Brown adipose tissue genes in pericardial adipose tissue of newborn sheep are downregulated by maternal nutrient restriction in late gestation.

BACKGROUND: Brown adipose tissue (BAT) thermogenesis is essential for newborn survival. Pericardial adipose tissue is a visceral depot that promotes metabolic and cardiovascular adaptations. We determined whether BAT is present in pericardial adipose tissue in newborns and whether maternal nutrition during late gestation compromises BAT in the postnatal period. METHODS: We measured uncoupling protein 1 (UCP1) and other BAT-specific genes (e.g., ß3-adrenergic receptor (ß3ADR) and deiodinase type 2 (DIO2)), together with markers of white adipose tissue (WAT) in sheep on either the first or 30th day after birth. These were twin offspring born to mothers fed with either 100% or nutrient restricted (NR) to 60% of their total metabolizable requirements from 110 d gestation to term. RESULTS: Gene expression of UCP1 and other BAT-related genes decreased significantly with age. In newborns, maternal nutrient restriction downregulated gene expression of DIO2 and the ß3-adrenergic receptor with reduced UCP1 but had no effect on genes predominantly expressed in WAT. CONCLUSION: BAT is present around the heart in newborns. Exposure to a suboptimal maternal diet in late gestation specifically compromises BAT development and has the potential to place these offspring at increased risk of hypothermia after birth without effects on the subsequent appearance of WAT.

Excess nutrient supply in early life and its later metabolic consequences.

Suboptimal nutrition in early life, both in utero and during infancy, is linked to increased risk of adult obesity and its associated adverse metabolic health problems. Excess nutrient supply during early life can lead to metabolic programming in the offspring. Such overnutrition can occur in the offspring of obese mothers, the offspring of mothers who gain excess weight during gestation, infants of diabetic mothers and infants who undergo rapid growth, particularly weight gain, during early infancy. Postnatal overnutrition is particularly detrimental for infants who are born small for gestational age, who are overfed to attain 'catch-up growth'. Potential mechanisms underlying metabolic programming that results from excess nutrition during early life include resetting of hypothalamic energy sensing and appetite regulation, altered adipose tissue insulin sensitivity and impaired brown adipose tissue function. More detailed understanding of the mechanisms involved in metabolic programming could enable the development of therapeutic strategies for ameliorating its ill effects. Research in this field could potentially identify optimal and appropriate preventative interventions for a burgeoning population at risk of increased mortality and morbidity from obesity and its concomitant metabolic conditions.

Association between opioid use during mechanical ventilation in preterm infants and evidence of brain injury: a propensity score-matched cohort study.

Background: Preterm infants often require mechanical ventilation (MV), which can be a painful experience. Opioids (such as morphine) are used to provide analgesia, despite conflicting evidence about their impact on the developing brain. We aimed to quantify the use of opioids during MV in infants born at <32 weeks' gestational age and to investigate the association between opioid use and evidence of brain injury. Methods: In this retrospective propensity score-matched cohort study, we used routinely recorded data from the National Neonatal Research Database to study infants born at 22-31 weeks gestational age who were admitted to neonatal units in England and Wales (between Jan 1, 2012, and Dec 31, 2020) and who were mechanically ventilated on one or more days during their hospital stay. We used propensity score matching to identify pairs of infants (one who received opioids during MV and one who did not) with similar demographic and clinical characteristics. The pre-specified primary outcome was preterm brain injury assessed in all infants who received MV for more than two days and had evidence of preterm brain injury at or before discharge from neonatal care. Adjusted analyses accounted for differences in infants' characteristics, including illness severity and painful/surgical conditions. Findings: Of 67,206 infants included, 45,193 (67%) were mechanically ventilated for one or more days and 26,201 (58% of 45,193) received an opioid whilst ventilated. Opioids were given for a median of 67% of ventilated days (IQR 43-92%) and the median exposure was 4 days (2-11). The percentage of mechanically ventilated infants who received opioids while ventilated increased from 52% in 2012 to 60% in 2020 (morphine, 51%-56%; fentanyl, 6%-18%). In the propensity score-matched cohort of 3608 pairs who were ventilated for >2 consecutive days, the odds of any preterm brain injury (adjusted odds ratio 1.22, 95% CI 1.10-1.35) were higher in those who received opioids compared with those who did not (received opioids, 990/3608 (27.4%) vs. did not receive opioids, 855/3608 (23.7%). The adjusted odds of these adverse outcomes increased with increasing number of days of opioid exposure. Interpretation: Use of opioids during mechanical ventilation of preterm infants increased during the study period (2012-2020). Although causation cannot be determined, among those ventilated for >2 consecutive days, these data suggest that opioid use is associated with an increased risk of preterm brain injury and the risk increases with longer durations of exposure. Funding: University of Nottingham Impact Fund.

Observational cohort study of use of caffeine in preterm infants and association between early caffeine use and neonatal outcomes.

OBJECTIVE: To quantify trends in caffeine use in infants born at <32 weeks' gestational age (GA), and to investigate the effects of early vs late caffeine on neonatal outcomes. STUDY DESIGN: Retrospective propensity score matched cohort study using routinely recorded data from the National Neonatal Research Database of infants born at <32 weeks' GA admitted to neonatal units in England and Wales (2012-2020). RESULTS: 89% (58 913/66 081) of infants received caffeine. In 70%, caffeine was started early (on the day of birth or the day after), increasing from 55% in 2012 to 83% in 2020. Caffeine was given for a median (IQR) of 28 (17-43) days starting on day 2 (1-3) and continued up to 34 (33-34) weeks postmenstrual age.In the propensity score matched cohort of 13 045 pairs of infants, the odds of preterm brain injury (early caffeine, 2306/13 045 (17.7%) vs late caffeine, 2528/13 045 (19.4%), OR=0.89 (95% CI 0.84 to 0.95)) and bronchopulmonary dysplasia (BPD) (early caffeine, 4020/13 045 (32.8%) vs late caffeine, 4694/13 045 (37.7%), OR=0.81 (95% CI 0.76 to 0.85)) were lower in the group that received early caffeine compared with those who received it later. CONCLUSIONS: Early use of caffeine has increased in England and Wales. This is associated with reduced risks of BPD and preterm brain injury. Randomised trials are needed to find the optimal timing of caffeine use and the groups of infants who will benefit most from early administration of caffeine.

Thermal imaging to assess age-related changes of skin temperature within the supraclavicular region co-locating with brown adipose tissue in healthy children.

OBJECTIVE: To establish the feasibility of infrared thermal imaging as a reproducible, noninvasive method for assessing changes in skin temperature within the supraclavicular region in vivo. STUDY DESIGN: Thermal imaging was used to assess the effect of a standard cool challenge (by placement of the participant's feet or hand in water at 20°C) on the temperature of the supraclavicular region in healthy volunteer participants of normal body mass index in 3 age groups, 3-8, 13-18, and 35-58 years of age. RESULTS: We demonstrated a highly localized increase in temperature within the supraclavicular region together with a significant age-related decline under both baseline and stimulated conditions. CONCLUSION: Thermogenesis within the supraclavicular region can be readily quantified by thermal imaging. This noninvasive imaging technique now has the potential to be used to assess brown adipose tissue function alone, or in combination with other techniques, in order to determine the roles of thermogenesis in energy balance and, therefore, obesity prevention.