Long duration of hyperglycemia in the first 96 hours of life is associated with severe intraventricular hemorrhage in preterm infants

Insulin resistance prior to term age in very low birthweight infants: a prospective study

OBJECTIVE

To explore the glucose-related hormone profile of very low birthweight (VLBW) infants and assess the association between neonatal hyperglycaemia and insulin resistance during the admission period.

DESIGN

A prospective observational study-the Very Low Birth Weight Infants, Glucose and Hormonal Profiles over Time study.

SETTING

A tertiary neonatal intensive care unit and four neonatal units in county hospitals in Sweden.

PATIENTS

48 infants born <1500 g (VLBW) during 2016-2019.

OUTCOME MEASURES

Plasma concentrations of glucose-related hormones and proteins (C-peptide, insulin, ghrelin, glucagon-like peptide 1 (GLP-1), glucagon, leptin, resistin and proinsulin), insulin:C-peptide and proinsulin:insulin ratios, Homoeostatic Model Assessment 2 (HOMA2) and Quantitative Insulin Sensitivity Check (QUICKI) indices, measured on day of life (DOL) 7 and at postmenstrual age 36 weeks.

RESULTS

Lower gestational age was significantly associated with higher glucose, C-peptide, insulin, proinsulin, leptin, ghrelin, resistin and GLP-1 concentrations, increased HOMA2 index, and decreased QUICKI index and proinsulin:insulin ratio. Hyperglycaemic infants had significantly higher glucose, C-peptide, insulin, leptin and proinsulin concentrations, and lower QUICKI index, than normoglycaemic infants. Higher glucose and proinsulin concentrations and insulin:C-peptide ratio, and lower QUICKI index on DOL 7 were significantly associated with longer duration of hyperglycaemia during the admission period.

CONCLUSIONS

VLBW infants seem to have a hormone profile consistent with insulin resistance. Lower gestational age and hyperglycaemia are associated with higher concentrations of insulin resistance markers.

A Higher Amount of Nutritional Intake as a Possible Cause of Hyperglycemia in Extremely Premature Infants in Parenteral and Enteral Nutrition at the Tertiary Neonatal Intensive Care Unit

BACKGROUND

This study aimed to find an association between infants who had hyperglycemia and those who did not, those treated with insulin or not and several prenatal and postnatal variables or the suboptimal prescription of parenteral nutrition.

METHODS

We conducted a retrospective study, which included extremely premature infants (<28 weeks of gestation) admitted to the tertiary NICU, University Medical Centre Ljubljana, between 1 January 2021 and 31 December 2021. Blood glucose measurements, insulin treatment, general characteristics, nutritional data and complications of prematurity were obtained retrospectively from hospital data.

RESULTS

There were 21 infants included in the study who did not receive insulin and 17 who were treated with insulin. Infants receiving insulin were younger and lighter compared to the non-insulin treatment group (mean gestational age 178 vs. 188 days; median birth weight 680 g vs. 990 g). The younger insulin group of infants received the same daily number of total macronutrients per kg per day compared to the older non-insulin group, i.e., glucose, lipids and amino acids, as recommended for the gestational age and birth weight. After adjusting for gestational age, no significant association with complications of prematurity was found.

CONCLUSIONS

The postulated explanation (with the prescription of a higher amount of macronutrients during the first seven days) for hyperglycemia and treatment with insulin in the less mature and lighter infants cannot be supported by the data given.

Hyperglycemia and prematurity: a narrative review

Hyperglycemia is commonly encountered in extremely preterm newborns and physiologically can be attributed to immaturity in several biochemical pathways related to glucose metabolism. Although hyperglycemia is associated with a variety of adverse outcomes frequently described in this population, evidence for causality is lacking. Variations in definitions and treatment approaches have further complicated the understanding and implications of hyperglycemia on the immediate and long-term effects in preterm newborns. In this review, we describe the relationship between hyperglycemia and organ development, outcomes, treatment options, and potential gaps in knowledge that need further research. IMPACT: Hyperglycemia is common and less well described than hypoglycemia in extremely preterm newborns. Hyperglycemia can be attributed to immaturity in several cellular pathways involved in glucose metabolism in this age group. Hyperglycemia has been shown to be associated with a variety of adverse outcomes frequently described in this population; however, evidence for causality is lacking. Variations in definitions and treatment approaches have complicated the understanding and the implications of hyperglycemia on the immediate and long-term effects outcomes. This review describes the relationship between hyperglycemia and organ development, outcomes, treatment options, and potential gaps in knowledge that need further research.

The incidence of and risk factors for hyperglycemia and hypoglycemia in preterm infants receiving early-aggressive parenteral nutrition

Introduction

Optimizing nutritional support helps prevent extra uterine growth restriction and adverse long-term outcomes in preterm infants.

Objectives

This study aimed to analyze the incidence of and risk factors for hyperglycemia and hypoglycemia in preterm infants receiving early-aggressive parenteral nutrition (PN).

Methods

This prospective observational study included preterm infants receiving PN at the Neonatal Intensive Care Unit of Dr. Soetomo General Hospital between April 2018 and May 2019. Potential risk factors analyzed included asphyxia, sepsis, respiratory distress syndrome, multiple congenital anomalies, mortality, necrotizing enterocolitis, retinopathy of prematurity, the postoperative period, inotropic administration, glucose infusion rate (GIR) > 10-12 mg/kg/min, GIR 4-<5.5 mg/kg/min, and increase in GIR <1 mg/kg/min.

Results

Of the 105 preterm infants included, hyperglycemia and hypoglycemia were found in 14 (13.3%) and 26 (24.8%) infants, respectively, with most incidents occurring in the first week (hyperglycemia: 85.7%; hypoglycemia: 88.5%). Sepsis was an independent risk factor for hyperglycemia (odds ratio [OR]: 8.743, 95% confidence interval [CI]: 2.392-31.959; P = 0.001). Hypoglycemia independent risk factors included the postoperative period (OR: 4.425, 95% CI: 1.218-16.073; P = 0.024) and use of GIR 4-<5.5 mg/kg/min (OR: 2.950, 95% CI: 1.035-8.405; P = 0.043).

Conclusion

Hyperglycemia and hypoglycemia can occur in preterm infants receiving early-aggressive PN; most cases occur within the first week of life. Hypoglycemia correlated with low glucose intake, and hyperglycemia correlated with sepsis. Monitoring blood glucose levels in preterm infants receiving PN, especially in the first weeks of life, may decrease morbidity associated with hyperglycemia or hypoglycemia.

Severity and duration of dysglycemia and brain injury among patients with neonatal encephalopathy

Background

Evidence is needed to inform thresholds for glycemic management in neonatal encephalopathy (NE). We investigated how severity and duration of dysglycemia relate to brain injury after NE.

Methods

A prospective cohort of 108 neonates ≥36 weeks gestational age with NE were enrolled between August 2014 and November 2019 at the Hospital for Sick Children, in Toronto, Canada. Participants underwent continuous glucose monitoring for 72 h, MRI at day 4 of life, and follow-up at 18 months. Receiver operating characteristic curves were used to assess the predictive value of glucose measures (minimum and maximum glucose, sequential 1 mmol/L glucose thresholds) during the first 72 h of life (HOL) for each brain injury pattern (basal ganglia, watershed, focal infarct, posterior-predominant). Linear and logistic regression analyses were used to assess the relationship between abnormal glycemia and 18-month outcomes (Bayley-III composite scores, Child Behavior Checklist [CBCL] T-scores, neuromotor score, cerebral palsy [CP], death), adjusting for brain injury severity.

Findings

Of 108 neonates enrolled, 102 (94%) had an MRI. Maximum glucose during the first 48 HOL best predicted basal ganglia (AUC = 0.811) and watershed (AUC = 0.858) injury. Minimum glucose was not predictive of brain injury (AUC <0.509). Ninety-one (89%) infants underwent follow-up assessments at 19.0 ± 1.7 months. A glucose threshold of >10.1 mmol/L during the first 48 HOL was associated with 5.8-point higher CBCL Internalizing Composite T-score (P = 0.029), 0.3-point worse neuromotor score (P = 0.035), 8.6-fold higher odds for CP diagnosis (P = 0.014). While the glucose threshold of >10.1 mmol/L during the first 48 HOL was associated with higher odds of the composite outcome of severe disability or death (OR 3.0, 95% CI 1.0-8.4, P = 0.042), it was not associated with the composite outcome of moderate-to-severe disability or death (OR 0.9, 95% CI 0.4-2.2, P = 0.801). All associations with outcome lost significance after adjusting for brain injury severity.

Interpretation

Maximum glucose concentration in the first 48 HOL is predictive of brain injury after NE. Further trials are needed to assess if protocols to control maximum glucose concentrations improve outcomes after NE.

Funding

Canadian Institutes for Health Research, National Institutes of Health, and SickKids Foundation.

Glucose variability increases during minimally invasive procedures in very preterm infants

The objective of this study is to assess the effect of neonatal procedures on glucose variability in very preterm infants. Preterm infants (≤ 32 weeks gestation and/or birthweight ≤ 1500 g) were started on continuous glucose monitoring (CGM) on day 2 of birth and monitored for 5 days. Minimally invasive (heel stick, venipunctures) and non-invasive (nappy change, parental presence) procedures were recorded. CGM data were analyzed 30 min before and after each procedure. The primary outcome was the coefficient of glucose variation (CV = SD/mean) before and after the procedure; SD and median glucose were also evaluated. We analyzed 496 procedures in 22 neonates (GA 30.5 weeks [29-31]; birthweight 1300 g [950-1476]). Median glucose did not change before and after each procedure, while CV and SD increased after heel prick (p = 0.017 and 0.030), venipuncture (p = 0.010 and 0.030), and nappy change (p < 0.001 and < 0.001), in the absence of a difference during parental presence.

CONCLUSIONS

Non-invasive and minimally invasive procedures increase glucose variability in the absence of changes of mean glucose.

WHAT IS KNOWN

• Minimally invasive procedures - including nappy change - may increase neonatal stress in preterm infants.

WHAT IS NEW

• Continuous glucose monitoring provides a quantitative measure of neonatal stress during neonatal care procedures demonstrating an increase of glucose variability.

Pathogenesis and prevention of intraventricular hemorrhage

Despite improvements in the mortality rates of preterm infants, rates of germinal matrix intraventricular hemorrhage (IVH) have remained static with an overall incidence of 25% in infants less than 32 weeks. The importance of the lesion relates primarily to the underlying injury to the developing brain and the associated long-term neurodevelopmental consequences. This clinical-orientated review focuses on the pathogenesis of IVH and discusses the evidence behind proposed prevention strategies.

Outcomes of very preterm infants with neonatal hyperglycaemia: a systematic review and meta-analysis

OBJECTIVE

To explore the association between hyperglycaemia and adverse outcomes in very preterm infants.

DESIGN

Systematic review and meta-analysis. Data were pooled separately for adjusted and unadjusted odds ratios (ORs) using random-effects model. Subgroup analysis was conducted based on study design (cohort and case control).

MAIN OUTCOME MEASURES

Association between hyperglycaemia in preterm neonates (<32 weeks or <1500 g) and mortality and morbidities.

FINDINGS

Forty-six studies (30 cohort and 16 case control) with data from 34 527 infants were included. Meta-analysis of unadjusted ORs from cohort studies found hyperglycaemia to be significantly associated with mortality, any-grade intraventricular haemorrhage (IVH), severe IVH, any-stage retinopathy of prematurity (ROP), severe ROP, sepsis, chronic lung disease and disability. However, pooling of adjusted ORs found significant associations only for mortality (adjusted OR (CI): 2.37 (1.40 to 4.01); I²: 36%; 6 studies), 'Any grade IVH' (adjusted OR (CI): 2.60 (1.09 to 6.20); I²: 0%; 2 studies) and 'Any stage ROP' (adjusted OR (CI): 3.70 (1.55 to 8.84); I²: 0%; 2 studies). Meta-regression analysis found glucose levels >10 mmol/L to be associated with increased odds of mortality compared with <10 mmol/L. Pooled analysis from case-control studies were similar to cohort studies for most outcomes but limited by small sample size. Longer duration of hyperglycaemia was associated with adverse outcomes. GRADE of evidence was 'Low' or 'Very low'.

CONCLUSION

Hyperglycaemia in very preterm infants is associated with higher odds of mortality, any-grade IVH and any-stage ROP. A limitation was lack of availability of adjusted ORs from many of the included studies.

PROSPERO REGISTRATION NUMBER

CRD42020193016.

Strict glycaemic control in very low birthweight infants using a continuous glucose monitoring system: a randomised controlled trial

OBJECTIVE

To evaluate the efficacy of a strict glycaemic control protocol using a continuous glucose monitoring (CGM) in infants at high risk of dysglycaemia with the aim of reducing the number of dysglycaemic episodes.

DESIGN

Randomised controlled trial.

SETTING

Neonatal intensive care unit, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome.

PATIENTS

All infants <1500 g fed on parental nutrition (PN) since birth were eligible. A total of 63 infants were eligible and 48 were randomised.

INTERVENTION

All participants wore a CGM sensor and were randomised in two arms with alarms set at different cut-off values (2.61-10 mmol/L (47-180 mg/dL) vs 3.44-7.78 mmol/L (62-140 mg/dL)), representing the operative threshold requiring modulation of glucose infusion rate according to an innovative protocol.

MAIN OUTCOME MEASURES

The primary outcome was the number of severe dysglycaemic episodes (<2.61 mmol/L (47 mg/dL) or >10 mmol/L (180 mg/dL)) in the intervention group versus the control group, during the monitoring time.

RESULTS

We enrolled 47 infants, with similar characteristics between the two arms. The number of dysglycaemic episodes and of infants with at least one episode of dysglycaemia was significantly lower in the intervention group (strict group): respectively, 1 (IQR 0-2) vs 3 (IQR 1-7); (p=0.005) and 12 (52%) vs 20 (83%); p=0.047. Infants managed using the strict protocol had a higher probability of having normal glycaemic values: relative risk 2.87 (95% CI 1.1 to 7.3). They spent more time in euglycaemia: 100% (IQR 97-100) vs 98% (IQR 94-99), p=0.036. The number needed to treat to avoid dysglycaemia episodes is 3.2 (95% CI 1.8 to 16.6).

CONCLUSION

We provide evidence that CGM, combined with a protocol for adjusting glucose infusion, can effectively reduce the episodes of dysglycaemia and increase the percentage of time spent in euglycaemia in very low birthweight infants receiving PN in the first week of life.

Neurodevelopment of preterm infants with glucose and sodium abnormalities

BACKGROUND

Blood glucose and serum sodium abnormalities in very low birth weight infants may cause increased morbidity and mortality, but data regarding the long-term outcomes are limited. This study aimed to investigate the association between the peak and nadir blood glucose and serum sodium levels and neurodevelopmental outcomes in very low birth weight infants.

METHODS

A single-center retrospective medical record of 284 infants with birth weight<1500 g born between February 1, 2011 and January 31, 2015 was reviewed. We analyzed the correlation between peak and nadir blood glucose and serum sodium levels during hospitalization and Bayley Scales of Infant and Toddler Development, third edition at 6, 12, and 24 months of corrected age.

RESULTS

A total of 284 very low birth weight premature infants were eligible, and 223, 208, and 188 patients were assessed at 6, 12, and 24 months of corrected age, respectively. Multiple linear regression analysis with generalized estimating equations showed that the BSID-III cognitive scores were significantly lower in the peak serum sodium group when sodium was ≧150 mmol/L (95% confidence interval -11.681 to -0.822) than when sodium did not exceed 150 mmol/L.

CONCLUSION

A peak serum sodium of ≧150 mmol/L is associated with poor cognitive outcomes in very low birth weight infants. Further studies are necessary to determine if this association is causal or an expression of disease severity.

Hyperglycemia associated with acute brain injury in neonatal encephalopathy

OBJECTIVE

To identify how alterations in glucose levels are associated with regional brain injury in neonatal encephalopathy.

METHODS

This was a prospective cohort study of 102 newborns with neonatal encephalopathy, with continuous glucose monitoring for 72 h. 97 (95%) completed 72 h of therapeutic hypothermia. Brain imaging around day 5 of life included diffusion tensor imaging and MR spectroscopy. Regions of interest were placed for both DTI and MR spectroscopy, and tractography of the optic radiation and corticospinal tract were evaluated. Linear regression models related each MR metric with minimum and maximum glucose values during each day of life, adjusting for 5-minute Apgar scores and umbilical artery pH.

RESULTS

Higher maximum glucose levels on the first day of life were associated with widespread changes in mean diffusivity in the anterior and posterior white matter, splenium of the corpus callosum, lentiform nucleus, pulvinar nucleus of the thalamus, posterior limb of the internal capsule, and optic radiations, thus including regions traditionally associated with hypoxia-ischemia or hypoglycemia. No associations were found between lower minimum glucose levels and DTI changes in any regions tested, or between glucose levels and MR spectroscopy.

CONCLUSIONS

In this cohort of neonatal encephalopathy with therapeutic hypothermia, higher maximal glucose on the first day of life was associated with widespread microstructural changes, but lower minimum glucose levels were not associated with changes in any of the regions tested. Long-term follow-up will determine if imaging findings translate to long-term outcomes.

Influence of innate immune activation on endocrine and metabolic pathways in infancy

Prematurity is the leading cause of neonatal morbidity and mortality worldwide. Premature infants often require extended hospital stays, with increased risk of developing infection compared with term infants. A picture is emerging of wide-ranging deleterious consequences resulting from innate immune system activation in the newborn infant. Those who survive infection have been exposed to a stimulus that can impose long-lasting alterations into later life. In this review, we discuss sepsis-driven alterations in integrated neuroendocrine and metabolic pathways and highlight current knowledge gaps in respect of neonatal sepsis. We review established biomarkers for sepsis and extend the discussion to examine emerging findings from human and animal models of neonatal sepsis that propose novel biomarkers for early identification of sepsis. Future research in this area is required to establish a greater understanding of the distinct neonatal signature of early and late-stage infection, to improve diagnosis, curtail inappropriate antibiotic use, and promote precision medicine through a biomarker-guided empirical and adjunctive treatment approach for neonatal sepsis. There is an unmet clinical need to decrease sepsis-induced morbidity in neonates, to limit and prevent adverse consequences in later life and decrease mortality.

Neonatal Hypoglycemia and Brain Vulnerability

Neonatal hypoglycemia is a common condition. A transient reduction in blood glucose values is part of a transitional metabolic adaptation following birth, which resolves within the first 48 to 72 h of life. In addition, several factors may interfere with glucose homeostasis, especially in case of limited metabolic stores or increased energy expenditure. Although the effect of mild transient asymptomatic hypoglycemia on brain development remains unclear, a correlation between severe and prolonged hypoglycemia and cerebral damage has been proven. A selective vulnerability of some brain regions to hypoglycemia including the second and the third superficial layers of the cerebral cortex, the dentate gyrus, the subiculum, the CA1 regions in the hippocampus, and the caudate-putamen nuclei has been observed. Several mechanisms contribute to neuronal damage during hypoglycemia. Neuronal depolarization induced by hypoglycemia leads to an elevated release of glutamate and aspartate, thus promoting excitotoxicity, and to an increased release of zinc to the extracellular space, causing the extensive activation of poly ADP-ribose polymerase-1 which promotes neuronal death. In this review we discuss the cerebral glucose homeostasis, the mechanisms of brain injury following neonatal hypoglycemia and the possible treatment strategies to reduce its occurrence.

Hyperglycemia in Extremely Preterm Infants

Hyperglycemia after birth is common in extremely preterm infants (<28 weeks of gestation). Lower gestational age, lower birthweight, presence of severe illness, and higher parenteral glucose intake increase the risk for hyperglycemia, while provision of higher amounts of amino acids and lipids in parenteral nutrition and early initiation and faster achievement of full enteral feeding decrease the risk. Hyperglycemia is associated with increased mortality and morbidity in the neonatal period. Limited data show an association with long-term adverse effects on growth, neurodevelopment, and cardiovascular and metabolic health. Lowering the glucose infusion rate and administration of insulin are the 2 treatment options. Lowering the glucose infusion could lead to calorie deficits and long-term adverse effects on growth and neurodevelopment. Conversely, insulin use increases the risk for hypoglycemia and requires close blood glucose monitoring and frequent adjustments to glucose infusion and insulin dosage. Randomized trials of varying strategies of nutrient provision and/or insulin therapy and long-term follow-up are needed to improve clinical care and overall health of extremely preterm infants with hyperglycemia.

Hyperglycaemia in the Newborn Infant. Physiology Verses Pathology

Hyperglycemia is common in newborns requiring intensive care, particularly in preterm infants, in sepsis and following perinatal hypoxia. The clinical significance, and optimal intervention strategy varies with context, but hyperglycaemia is associated with increased mortality and morbidity. The limited evidence for optimal clinical targets mean controversy remains regarding thresholds for intervention, and management strategies. The first consideration in the management of hyperglycaemia must be to ascertain potentially treatable causes. Calculation of the glucose infusion rate (GIR) to insure this is not excessive, is critical but the use of insulin is often helpful in the extremely preterm infant, but is associated with an increased risk of hypoglycaemia. The use of continuous glucose monitoring (CGM) has recently been demonstrated to be helpful in targeting glucose control, and reducing the risk from hypoglycaemia in the preterm infant. Its use in other at risk infants remains to be explored, and further studies are needed to provide a better understanding of the optimal glucose targets for different clinical conditions. In the future the combination of CGM and advances in computer algorithms, to provide intelligent closed loop systems, could allow a safer and more personalized approached to management.

Relationships between Early Nutrition, Illness, and Later Outcomes among Infants Born Preterm with Hyperglycemia

OBJECTIVE

To evaluate the effects of hyperglycemia on body composition and neurodevelopment, and how early nutrition and illness modify these relationships in infants born preterm.

STUDY DESIGN

Prospective data were collected from infants born <32 weeks of gestational age (N = 97), including inpatient days of hyperglycemia (blood glucose >150 mg/dL) and nutrient intake. Body composition was measured at discharge and 4 months' postmenstrual age (PMA). Bayley Scales of Infant Development III (BSID-III) were administered at 12 months' PMA. Linear regression analysis was performed, adjusting for birth gestational age. Associations between hyperglycemia, body composition, and BSID-III were analyzed in models accounting for first-week nutrition and early illness severity via Score for Neonatal Acute Physiology-II.

RESULTS

Mean birth gestational age was 27.8 (SD 2.4) weeks. Hyperglycemia occurred in 48.5% of infants. Hyperglycemia for ≥5 days was negatively associated with fat mass and fat free mass z scores at discharge, and fat free mass z score at 4 months' PMA (P < .05 all). Hyperglycemia for ≥5 days was negatively associated with cognition, language, and motor scores on the BSDI at 12 months (P ≤ .01 all). Associations with body composition and BSID-III were diminished when models included first week nutrition yet remained unchanged when illness severity was included.

CONCLUSIONS

In infants <32 weeks, ≥5 days of hyperglycemia is associated with decreased lean mass at 4 months' PMA and poorer neurodevelopmental outcome at 12 months' PMA. These associations may be mediated by decreased first week nutrition, potentially related to reduced glucose infusion rate for management of hyperglycemia.

Effects of Neonatal Hyperglycemia on Retinopathy of Prematurity and Visual Outcomes at 7 Years of Age: A Matched Cohort Study

OBJECTIVE

To determine whether neonatal hyperglycemia is associated with retinopathy of prematurity (ROP), visual outcomes, and ocular growth at 7 years of age.

STUDY DESIGN

Children born preterm (<30 weeks of gestational age) at a tertiary hospital in Auckland, New Zealand, who developed neonatal hyperglycemia (2 blood glucose concentrations ≥153 mg/dL [8.5 mmol/L] 4 hours apart) were matched with children who were not hyperglycemic (matching criteria: sex, gestational age, birth weight, age, socioeconomic status, and multiple birth) and assessed at 7 years of corrected age. The primary outcome, favorable overall visual outcome (visual acuity ≤0.3 logarithm of the minimum angle of resolution, no strabismus, stereoacuity ≤240 arcsec, not requiring spectacles) was compared between groups using generalized matching criteria-adjusted linear regression models.

RESULTS

Assessments were performed on 57 children with neonatal hyperglycemia (hyperglycemia group) and 54 matched children without hyperglycemia (control group). There were no differences in overall favorable visual outcome (OR 0.95, 95% CI 0.42-2.13, P = .90) or severe ROP incidence (OR 2.20, 95% CI 0.63-7.63, P = .21) between groups. Children with hyperglycemia had poorer binocular distance visual acuity (mean difference 0.08, 95% CI 0.03-0.14 logarithm of the minimum angle of resolution, P < .01), more strabismus (OR 6.22, 95% CI 1.31-29.45, P = .02), and thicker crystalline lens (mean difference 0.14, 95% CI 0.04-0.24 mm, P < .01). Maximum blood glucose concentration was greater in the ROP-treated group compared with the ROP-not treated and no ROP groups after adjusting for sex, gestational age, and birth weight z score (P = .02).

CONCLUSIONS

Neonatal hyperglycemia was not associated with overall visual outcomes at 7 years of age. However, there were between-group differences for specific outcome measures relating to interocular lens growth and binocular vision. Further follow-up is required to determine implications on long-term visual outcome.

Monitoring the incidence, duration and distribution of hyperglycaemia in very-low-birth-weight newborns and identifying associated factors

Objectives Hyperglycaemia is a common metabolic disorder in very-low-birth-weight (VLBW) infants and is associated with increased morbidity and mortality. The objective is to describe the incidence, duration, episodes and distribution of hyperglycaemia during the first 7 days of life of VLBW infants. Methods This is a prospective cohort study of 60 newborns weighing <1,500 g. Blood glucose levels were monitored with a continuous glucose monitoring system (CGMS) during the first 7 days of life. Hyperglycaemia was defined as glucose ≥180 mg/dL (≥10 mmol/L). Results Incidence of hyperglycaemia recorded with the CGMS was 36.6% (95%CI: 24.6-50.1). In almost 74.6±5.48% of these cases the duration of the episode exceeded 30 min and in 45.25% (95%CI: 2.26-57.82) it exceeded 2 h. The condition occurred most frequently during the first 72 h of life. One-fifth of cases were not detected with scheduled capillary tests and 84.6% of these had hyperglycaemic episode durations of 30 min or more. Agreement between the two techniques was very good (r=0.90, p<0.001) and the CGMS proved to be reliable, accurate and safe. Hyperglycaemia detected by a CGMS is associated with lower gestational age (OR: 0.66, p=0.002), lower birth weight (OR: 0.99, p=0.003), the use of ionotropic drugs (OR: 11.07, p=0.005) and death (OR: 10.59, p=0.03), and is more frequent in preterm infants with sepsis (OR: 2.73, p=0.1). No other association was observed. Conclusions A CGMS could be useful during the first week of life in VLBW infants due to the high incidence and significant duration of hyperglycaemia and the high proportion of cases that remain undetected. The advantage of the CGMS is that it is able to detect hyperglycaemic episodes that the capillary test does not.

Continuous Glucose Monitoring Linked to an Artificial Intelligence Risk Index: Early Footprints of Intraventricular Hemorrhage in Preterm Neonates

OBJECTIVE

To develop and validate a new risk score for intraventricular hemorrhage (IVH) in preterm neonates based on continuous glucose monitoring (CGM).

STUDY DESIGN

We retrospectively analyzed CGM traces obtained from 50 very preterm neonates, grouped into two sub-cohorts started on CGM within 12 and 48 h of birth, respectively. A CGM linked to an Artificial Intelligence Risk (CLAIR) index was developed to quantify glucose variability during the first 72 h of life in neonates with and without IVH. Brain-US was performed at least twice a day for the first 5 days of birth. An integrated remote monitoring platform was developed to capture major clinical events in real time and gather data for the risk index. The new score performance was further compared with other measures of glucose variability (coefficient of variation [CV] and standard deviation [SD]) and with a clinical risk index for babies II (CRIB-II) as a predictor of IVH event. The two cohorts were analyzed separately for internal validation of the method.

RESULTS

The primary cohort consisted of 26 neonates (gestational age 30 [28, 31] weeks; BW1275 g[1090, 1750]). Controls (n = 23) exhibited higher CLAIR index than cases (P = 0.004). A cut-off of 0.69 for the new CLAIR index allowed a 100% sensitivity and an 83% specificity for IVH prediction. The CLAIR index was the sole significant predictor for IVH (P = 0.003) when compared with clinical variables, CV, SD, and CRIB-II. In a subgroup analysis in very low-birth-weight infants, the CLAIR index was the sole variable significantly associated with IVH (P = 0.009). Analysis on the secondary cohort (five cases and 16 controls) confirmed a higher CLAIR index in the controls (P = 0.008), in the absence of a difference for CV, SD, and CRIB-II between the two groups.

CONCLUSION

CGM, combined with the AI-algorithm, provides a high-sensitivity index for risk detection of IVH that reflects the glycemic impairment preceding IVH.

Targeted urine metabolomics in preterm neonates with intraventricular hemorrhage

Intraventricular hemorrhage (IVH) is a major cause of morbidity and mortality in preterm neonates. Elucidation of the mechanisms underlying IVH and/or development of disease biomarkers is essential. The aim of the study was to investigate the urine metabolic profile of preterm neonates (gestational age < 32 weeks) IVH and explore the role of metabolomics in understanding pathophysiological mechanisms of the disease from which novel biomarkers could be derived. In this single-center, prospective, case-control study, urine samples were collected from seven preterm infants with early IVH (IVH group) and from 11 preterm ones without IVH (control group) on days 1, 3 and 9 of life. Urine metabolites were evaluated using targeted liquid chromatography-tandem mass spectrometry. Demographic and perinatal-clinical characteristics were recorded. Univariate and multivariate statistical analyses were performed. Orthogonal Partial Least Squares-Discriminant Analysis showed that the study groups differed significantly due to alternation in 20 out of the 40 metabolites detected in the urine. Elevated differentiated metabolites included energy intermediates and other important compounds, whereas reduced ones various amino acids, hypoxanthine and nicotinamide. A set of metabolites showed high performance as indicators of IVH, especially during day 1. As evidenced by metabolomics, preterm neonates with IVH demonstrate significant metabolism perturbations. Potentially, a selected panel of metabolites could be used as urine biomarkers of IVH development and/or progression in high-risk preterm infants.

Hyperglycemia in Extremely Preterm Infants-Insulin Treatment, Mortality and Nutrient Intakes

OBJECTIVE

To explore the prevalence of hyperglycemia and the associations between nutritional intakes, hyperglycemia, insulin treatment, and mortality in extremely preterm infants.

STUDY DESIGN

Prospectively collected data from the Extremely Preterm Infants in Sweden Study (EXPRESS) was used in this study and included 580 infants born <27 gestational weeks during 2004-2007. Available glucose measurements (n = 9850) as well as insulin treatment and nutritional data were obtained retrospectively from hospital records for the first 28 postnatal days as well as 28- and 70-day mortality data.

RESULTS

Daily prevalence of hyperglycemia >180 mg/dL (10 mmol/L) of up to 30% was observed during the first 2 postnatal weeks, followed by a slow decrease in its occurrence thereafter. Generalized additive model analysis showed that increasing parenteral carbohydrate supply with 1 g/kg/day was associated with a 1.6% increase in glucose concentration (P < .001). Hyperglycemia was associated with more than double the 28-day mortality risk (P < .01). In a logistic regression model, insulin treatment was associated with lower 28- and 70-day mortality when given to infants with hyperglycemia irrespective of the duration of the hyperglycemic episode (P < .05).

CONCLUSIONS

Hyperglycemia is common in extremely preterm infants throughout the first postnatal month. Glucose infusions seem to have only a minimal impact on glucose concentrations. In the EXPRESS cohort, insulin treatment was associated with lower mortality in infants with hyperglycemia. Current practices of hyperglycemia treatment in extremely preterm infants should be reevaluated and assessed in randomized controlled clinical trials.

Blood Glucose and Cerebral Tissue Oxygenation Immediately after Birth-An Observational Study

OBJECTIVE

To assess a possible association of blood glucose concentration with cerebral regional oxygen saturation (crSO₂) and cerebral fractional tissue oxygen extraction (cFTOE) in neonates born at term and preterm 15 minutes after birth.

STUDY DESIGN

A post-hoc analysis of secondary outcome measures of 2 prospective observational studies was performed. Neonates born at term and preterm via cesarean delivery were included if cerebral near-infrared spectroscopy measurements were performed during the immediate transition after birth and blood glucose concentrations were measured at 15-20 minutes after birth. Arterial oxygen saturation and heart rate were measured with pulse oximetry. cFTOE was calculated from arterial oxygen saturation and crSO₂ values. crSO₂ and cFTOE 15 minutes after birth were correlated with blood glucose concentrations.

RESULTS

Seventy-five infants were included. In 50 neonates born at term, crSO₂ and cFTOE 15 minutes after birth were 83 ± 7.7% and 0.14 ± 0.08, respectively. In 25 neonates born preterm, crSO₂ and cFTOE 15 minutes after birth were 80.2 ± 12.1%, and 0.15 ± 0.1, respectively. crSO₂ and cFTOE correlated significantly with blood glucose concentrations in neonates born at term and preterm. Increasing blood glucose concentrations were associated with decreasing crSO₂ in neonates born at term (q = -0.35, P = .01) and neonates born preterm (q = -0.69, P = .01) and with increasing cFTOE in neonates born at term (q = 0.31, P = .03) and neonates born preterm (q = 0.67, P = .01).

CONCLUSIONS

Blood glucose concentration was associated with cerebral oxygenation during the immediate transition after birth in neonates born at term and preterm.

Relationships Between Early Nutrition and Blood Glucose Concentrations in Very Preterm Infants

OBJECTIVES

The aim of the study was to determine whether changes to early nutrition are associated with levels of glycemia in very preterm infants.

METHODS

A retrospective, observational study of infants <1500 g or <30 weeks' gestation admitted to Neonatal Intensive Care, National Women's Hospital, New Zealand, before (Old Protocol) and after (New Protocol) a change in nutritional protocol. Nutritional intakes were calculated and averaged by day for postnatal days 1 to 7 (week 1) and 1 to 28 (month 1). Relationships between glycemia measures, macronutrient intakes, and achievement of 10% enteral feeds (≥10% total intake) were explored using logistic regression.

RESULTS

Old Protocol (n = 190) and New Protocol (n = 267) groups had similar baseline characteristics. In week 1, New Protocol infants received more protein, less fat, and carbohydrate, had lower mean blood glucose concentrations (BGCs) (mean ± SD 4.9 ± 1.2 vs 5.6 ± 1.4 mmoll/L, P < 0.0001), less hyperglycemia (BGC > 8.5 mmol/L, 71 [27%] vs 80 [42%], P = 0.0005), but similar hypoglycemia (BGC < 2.6). In month 1, New Protocol infants also had less hyperglycemia (105 [39%] vs 96 [51%], P = 0.02) and lower mean BGC (5.0 ± 1.1 vs 5.5 ± 1.1 mmol/L, P < 0.0001), but insulin usage was similar. After adjustment for birth weight z score and gestational age, hyperglycemia was significantly associated with week 1 intakes (g · kg · day) of protein (odds ratio [95% confidence intervals] 0.47 [0.23-0.79], P = 0.004), fat (0.54 [0.40-0.74], P < 0.0001), and carbohydrate (1.25 [1.09-1.44], P < 0.0001). These relationships were similar for month 1. Each additional day to achieve 10% enteral feeds was associated with increased odds of hypoglycemia (1.09 [1.00-1.18], P = 0.04) and hyperglycemia (1.16 [1.06-1.28], P = 0.002).

CONCLUSIONS

In very preterm infants, macronutrient balance and small, early enteral feeds may assist glycemic control.

Prematurity disrupts glomeruli development, whereas prematurity and hyperglycemia lead to altered nephron maturation and increased oxidative stress in newborn baboons

BackgroundPremature birth occurs when nephrogenesis is incomplete and has been linked to increased renal pathologies in the adult. Metabolic factors complicating preterm birth may have additional consequences for kidney development. Here, we evaluated the effects of prematurity and hyperglycemia on nephrogenesis in premature baboons when compared with those in term animals.MethodsBaboons were delivered prematurely (67% gestation; n=9) or at term (n=7) and survived for 2-4 weeks. Preterm animals were classified by glucose control during the first 5 days of life: normoglycemic (PtN; serum glucose 50-100 mg/dl, n=6) and hyperglycemic (PtH; serum glucose 150-250 mg/dl, n=3). Kidneys were assessed histologically for glomeruli relative area, maturity, size, and overall morphology. Kidney lysates were evaluated for oxidative damage with 4-hydroxynonenal (4-HNE) antibody.ResultsHistological examination revealed decreased glomeruli relative area (P<0.05), fewer glomerular generations (P<0.01), and increased renal corpuscle area (P<0.001) in preterm compared with those in term animals. Numbers of apoptotic glomeruli were similar between groups. PtH kidneys exhibited reduced nephrogenic zone width (P<0.0001), increased numbers of mature glomeruli (P<0.05), and increased 4-HNE staining compared with those in PtN kidneys.ConclusionPrematurity interrupts normal kidney development, independent of glomerular cell apoptosis. When prematurity is complicated by hyperglycemia; kidney development shifts toward accelerated maturation and increased oxidative stress.

Long-Term Outcomes of Hyperglycemic Preterm Infants Randomized to Tight Glycemic Control

OBJECTIVE

To determine whether tight glycemic control of neonatal hyperglycemia changes neurodevelopment, growth, and metabolism at school age.

STUDY DESIGN

Children born very low birth weight and randomized as hyperglycemic neonates to a trial of tight vs standard glycemic control were assessed at 7 years corrected age, including Wechsler Intelligence Scale for Children Fourth Edition, Movement Assessment Battery for Children 2, visual and neurologic examinations, growth measures, dual X-ray absorptiometry, and frequently sampled intravenous glucose tolerance test. The primary outcome was survival without neurodevelopmental impairment at age 7 years. Outcomes were compared using linear regression, adjusted for sex, small for gestational age, birth plurality, and the clustering of twins. Data are reported as number (%) or mean (SD).

RESULTS

Of the 88 infants randomized, 11 (13%) had died and 57 (74% of eligible children) were assessed at corrected age 7 years. Survival without neurodevelopmental impairment occurred in 25 of 68 children (37%), with no significant difference between tight (14 of 35; 40%) and standard (11 of 33; 33%) glycemic control groups (P = .60). Children in the tight group were shorter than those in the standard group (121.3 [6.3] cm vs 125.1 [5.4] cm; P < .05), but had similar weight and head circumference. Children in the tight group had greater height-adjusted lean mass (18.7 [0.3] vs 17.6 [0.2] kg; P < .01) and lower fasting glucose concentrations (84.6 [6.30] vs 90.0 [5.6] mg⋅dL^-1; P < .05), but no other differences in measures of body composition or insulin-glucose metabolism.

CONCLUSION

Tight glycemic control for neonatal hyperglycemia does not change survival without neurodevelopmental impairment, but reduces height, increases height-adjusted lean mass, and reduces fasting blood glucose concentrations at school age.

TRIAL REGISTRATION

ACTRN: 12606000270516.

Hepatic Insulin Resistance and Altered Gluconeogenic Pathway in Premature Baboons

Premature infants have altered glucose regulation early in life and increased risk for diabetes in adulthood. Although prematurity leads to an increased risk of diabetes and metabolic syndrome in adult life, the role of hepatic glucose regulation and adaptation to an early extrauterine environment in preterm infants remain unknown. The purpose of this study was to investigate developmental differences in glucose metabolism, hepatic protein content, and gene expression of key insulin-signaling/gluconeogenic molecules. Fetal baboons were delivered at 67%, 75%, and term gestational age and euthanized at birth. Neonatal baboons were delivered prematurely (67% gestation), survived for two weeks, and compared with similar postnatal term animals and underwent serial hyperinsulinemic-euglycemic clamp studies. Premature baboons had decreased endogenous glucose production (EGP) compared with term animals. Consistent with these results, the gluconeogenic molecule, phosphoenolpyruvate carboxykinase messenger RNA, was decreased in preterm baboons compared with terms. Hepatic insulin signaling was altered by preterm birth as evidenced by decreased insulin receptor-β, p85 subunit of phosphoinositide 3-kinase, phosphorylated insulin receptor substrate 1, and Akt-1 under insulin-stimulated conditions. Furthermore, preterm baboons failed to have the normal increase in glycogen synthase kinase-α from fetal to postnatal life. The blunted responses in hepatic insulin signaling may contribute to the hyperglycemia of prematurity, while impaired EGP leads to hypoglycemia of prematurity.

Does hyperglycemia in hypernatremic preterm infants increase the risk of intraventricular hemorrhage?

OBJECTIVE

Hypernatremia and hyperglycemia are highly prevalent in preterm infants during the first week after birth, and both can lead to hyperosmolarity and osmotic shifts. The objective is to determine whether hyperglycemia increases the risk of intraventricular hemorrhage (IVH) in hypernatremic preterm infants.

STUDY DESIGN

Single-center retrospective medical record review of 216 infants <1000 g birth weight and <29 weeks gestational age (admitted over a 9-year period) who had serum sodium levels and blood glucose levels monitored at least every 24 h and more frequently if indicated during the first 10 days after birth. Hyperglycemia was defined as persistently high blood glucose (usually >200 mg dl(-1)) treated with an insulin infusion. Hypernatremia was defined as a serum sodium level of ⩾150 mmol l(-1) on repeated measurements.

RESULTS

Of the 216 infants studied, 76 (35%) developed hyperglycemia and 126 (58%) developed hypernatremia. IVH developed more frequently in infants with hyperglycemia (P=0.006, odds ratio (OR) 2.3, 95% confidence interval (CI) 1.3 to 4.1), in infants with hypernatremia (P=0.018, OR 2.0, 95% CI 1.2 to 3.5) and in infants with hypernatremia plus hyperglycemia (P=0.001, OR 3.2, 95% CI 1.6 to 6.4). Multivariate regression analysis confirmed the independent association of higher risk of IVH with the presence of hypernatremia plus hyperglycemia (P=0.015, OR 2.6, 95% CI 1.2 to 5.5) but not with hypernatremia or hyperglycemia alone.

CONCLUSION

Hyperglycemia increases the risk of IVH in hypernatremic preterm infants.

Diminished growth and lower adiposity in hyperglycemic very low birth weight neonates at 4 months corrected age

OBJECTIVE

Characterize the relationship between neonatal hyperglycemia and growth and body composition at 4 months corrected age (CA) in very low birth weight (VLBW) preterm infants.

STUDY DESIGN

A prospective study of VLBW appropriate-for-gestation infants (N=53). All blood glucose measurements in the first 14 days and nutritional intake and illness markers until discharge were recorded. Standard anthropometrics and body composition via air displacement plethysmography were measured near term CA and 4 months CA. Relationships between hyperglycemia and anthropometrics and body composition were examined using multivariate linear regression.

RESULTS

Infants with >5 days of hyperglycemia were lighter (5345 vs 6455 g, P⩽0.001), shorter (57.9 vs 60.9 cm, P⩽0.01), had smaller occipital-frontal head circumference (39.4 vs 42.0 cm, P⩽0.05) and were leaner (percent body fat 15.0 vs 23.8, P⩽0.01) at 4 months CA than those who did not have hyperglycemia, including after correcting for nutritional and illness factors.

CONCLUSIONS

Neonatal hyperglycemia in VLBW infants is associated with decreased body size and lower adiposity at 4 months CA independent of nutritional deficit, insulin use and illness. Downregulation of the growth hormone axis may be responsible. These changes may influence long-term growth and cognitive development.

Congenital hyperinsulinemia with grade 4 intraventricular hemorrhage: a case report with a 2-year follow-up

Massive intraventricular hemorrhage associated with hypoglycemia has rarely been reported. We present a late preterm baby girl with severe hypoglycemia after birth. Despite high glucose infusion rates, her glucose levels remained in the 30s to 50s (mg/dL) during the first week of life with a brief period of normoglycemia. On day 2, her computed tomography scan of head showed extensive intraventricular hemorrhage with intraparenchymal extension, which was reported as unexpected for an infant born close to term. She was diagnosed with congenital hyperinsulinemia. Her glucose levels normalized on diazoxide therapy started on day 6. In the absence of any other clear cause, the massive brain hemorrhage was thought to be secondary to prolonged severe hypoglycemia the infant suffered. She remains in global developmental delay at her age at 26 months. This case highlights the importance of early referral of neonatal hypoglycemia for prompt diagnosis and management to avoid the consequences of prolonged low blood glucose.