Validation of the continuous glucose monitoring sensor in preterm infants

Neonatal dysglycemia: a review of dysglycemia in relation to brain health and neurodevelopmental outcomes

Neonatal dysglycemia has been a longstanding interest of research in neonatology. Adverse outcomes from hypoglycemia were recognized early but are still being characterized. Premature infants additionally introduced and led the reflection on the importance of neonatal hyperglycemia. Cohorts of infants following neonatal encephalopathy provided further information about the impacts of hypoglycemia and, more recently, highlighted hyperglycemia as a central concern for this population. Innovative studies exposed the challenges of management of neonatal glycemic levels with a "u-shape" relationship between dysglycemia and adverse neurological outcomes. Lately, glycemic lability has been recognized as a key factor in adverse neurodevelopmental outcomes. Research and new technologies, such as MRI and continuous glucose monitoring, offered novel insight into neonatal dysglycemia. Combining clinical, physiological, and epidemiological data allowed the foundation of safe operational definitions, including initiation of treatment, to delineate neonatal hypoglycemia as ≤47 mg/dL, and >150-180 mg/dL for neonatal hyperglycemia. However, questions remain about the appropriate management of neonatal dysglycemia to optimize neurodevelopmental outcomes. Research collaborations and clinical trials with long-term follow-up and advanced use of evolving technologies will be necessary to continue to progress the fascinating world of neonatal dysglycemia and neurodevelopment outcomes. IMPACT STATEMENT: Safe operational definitions guide the initiation of treatment of neonatal hypoglycemia and hyperglycemia. Innovative studies exposed the challenges of neonatal glycemia management with a "u-shaped" relationship between dysglycemia and adverse neurological outcomes. The importance of glycemic lability is also being recognized. However, questions remain about the optimal management of neonatal dysglycemia to optimize neurodevelopmental outcomes. Research collaborations and clinical trials with long-term follow-up and advanced use of evolving technologies will be necessary to progress the fascinating world of neonatal dysglycemia and neurodevelopment outcomes.

Impact of macronutrients intake on glycemic homeostasis of preterm infants: evidence from continuous glucose monitoring

Nutritional intake could influence the blood glucose profile during early life of preterm infants. We investigated the impact of macronutrient intake on glycemic homeostasis using continuous glucose monitoring (CGM). We analyzed macronutrient intake in infants born ≤ 32 weeks gestational age (GA) and/or with birth weight ≤ 1500 g. CGM was started within 48 h of birth and maintained for 5 days. Mild and severe hypoglycemia were defined as sensor glucose (SG) < 72 mg/dL and <47 mg/dL, respectively, while mild and severe hyperglycemia were SG > 144 mg/dL and >180 mg/dL. Data from 30 participants were included (age 29.9 weeks (29.1; 31.2), birthweight 1230.5 g (1040.0; 1458.6)). A reduced time in mild hypoglycemia was associated to higher amino acids intake (p = 0.011) while increased exposure to hyperglycemia was observed in the presence of higher lipids intake (p = 0.031). The birthweight was the strongest predictor of neonatal glucose profile with an inverse relationship between the time spent in hyperglycemia and birthweight (p = 0.007).  Conclusions: Macronutrient intakes influence neonatal glucose profile as described by continuous glucose monitoring. CGM might contribute to adjust nutritional intakes in preterm infants. What is Known: • Parenteral nutrition may affect glucose profile during the first days of life of preterm infants. What is New: • Continuous glucose monitoring describes the relationship between daily parenteral nutrient intakes and time spent in hypo and hyperglycemic ranges.

Hypoglycaemia in adrenal insufficiency

Adrenal insufficiency encompasses a group of congenital and acquired disorders that lead to inadequate steroid production by the adrenal glands, mainly glucocorticoids, mineralocorticoids and androgens. These may be associated with other hormone deficiencies. Adrenal insufficiency may be primary, affecting the adrenal gland's ability to produce cortisol directly; secondary, affecting the pituitary gland's ability to produce adrenocorticotrophic hormone (ACTH); or tertiary, affecting corticotrophin-releasing hormone (CRH) production at the level of the hypothalamus. Congenital causes of adrenal insufficiency include the subtypes of Congenital Adrenal Hyperplasia, Adrenal Hypoplasia, genetic causes of Isolated ACTH deficiency or Combined Pituitary Hormone Deficiencies, usually caused by mutations in essential transcription factors. The most commonly inherited primary cause of adrenal insufficiency is Congenital Adrenal Hyperplasia due to 21-hydroxylase deficiency; with the classical form affecting 1 in 10,000 to 15,000 cases per year. Acquired causes of adrenal insufficiency can be subtyped into autoimmune (Addison's Disease), traumatic (including haemorrhage or infarction), infective (e.g. Tuberculosis), infiltrative (e.g. neuroblastoma) and iatrogenic. Iatrogenic acquired causes include the use of prolonged exogenous steroids and post-surgical causes, such as the excision of a hypothalamic-pituitary tumour or adrenalectomy. Clinical features of adrenal insufficiency vary with age and with aetiology. They are often non-specific and may sometimes become apparent only in times of illness. Features range from those related to hypoglycaemia such as drowsiness, collapse, jitteriness, hypothermia and seizures. Features may also include signs of hypotension such as significant electrolyte imbalances and shock. Recognition of hypoglycaemia as a symptom of adrenal insufficiency is important to prevent treatable causes of sudden deaths. Cortisol has a key role in glucose homeostasis, particularly in the counter-regulatory mechanisms to prevent hypoglycaemia in times of biological stress. Affected neonates particularly appear susceptible to the compromise of these counter-regulatory mechanisms but it is recognised that affected older children and adults remain at risk of hypoglycaemia. In this review, we summarise the pathogenesis of hypoglycaemia in the context of adrenal insufficiency. We further explore the clinical features of hypoglycaemia based on different age groups and the burden of the disease, focusing on hypoglycaemic-related events in the various aetiologies of adrenal insufficiency. Finally, we sum up strategies from published literature for improved recognition and early prevention of hypoglycaemia in adrenal insufficiency, such as the use of continuous glucose monitoring or modifying glucocorticoid replacement.

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.

Continuous Glucose Monitoring in Transient Neonatal Diabetes Mellitus-2 Case Reports and Literature Review

Neonatal diabetes mellitus is a rare genetic disease that affects 1 in 90,000 live births. The start of the disease is often before the baby is 6 months old, with rare cases of onset between 6 months and 1 year. It is characterized by low or absent insulin levels in the blood, leading to severe hyperglycemia in the patient, which requires temporary insulin therapy in around 50% of cases or permanent insulin therapy in other cases. Two major processes involved in diabetes mellitus are a deformed pancreas with altered insulin-secreting cell development and/or survival or faulty functioning of the existing pancreatic beta cell. We will discuss the cases of two preterm girls with neonatal diabetes mellitus in this research. In addition to reviewing the literature on the topic, we examined the different mutations, patient care, and clinical outcomes both before and after insulin treatment.

Continuous glucose monitoring for children with hypoglycaemia: Evidence in 2023

In 2023, childhood hypoglycaemia remains a major public health problem and significant risk factor for consequent adverse neurodevelopment. Irrespective of the underlying cause, key elements of clinical management include the detection, prediction and prevention of episodes of hypoglycaemia. These tasks are increasingly served by Continuous Glucose Monitoring (CGM) devices that measure subcutaneous glucose at near-continuous frequency. While the use of CGM in type 1 diabetes is well established, the evidence for widespread use in rare hypoglycaemia disorders is less than convincing. However, in the few years since our last review there have been multiple developments and increased user feedback, requiring a review of clinical application. Despite advances in device technology, point accuracy of CGM remains low for children with non-diabetes hypoglycaemia. Simple provision of CGM devices has not replicated the efficacy seen in those with diabetes and is yet to show benefit. Machine learning techniques for hypoglycaemia prevention have so far failed to demonstrate sufficient prediction accuracy for real world use even in those with diabetes. Furthermore, access to CGM globally is restricted by costs kept high by the commercially-driven speed of technical innovation. Nonetheless, the ability of CGM to digitally phenotype disease groups has led to a better understanding of natural history of disease, facilitated diagnoses and informed changes in clinical management. Large CGM datasets have prompted re-evaluation of hypoglycaemia incidence and facilitated improved trial design. Importantly, an individualised approach and focus on the behavioural determinants of hypoglycaemia has led to real world reduction in hypoglycaemia. In this state of the art review, we critically analyse the updated evidence for use of CGM in non-diabetic childhood hypoglycaemia disorders since 2020 and provide suggestions for qualified use.

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.

Continuous Glucose Monitoring in Preterm Infants: The Role of Nutritional Management in Minimizing Glycemic Variability

Glycemic variability (GV) is common in preterm infants. In the premature population, GV is a risk factor for morbidity and mortality. Both hypo- and hyperglycemia can impair neurodevelopment. We investigated the impact of continuous versus intermittent tube enteral feeding on GV. In our prospective observational study, 20 preterm infants with a gestational age ≤ 34 weeks at either continuous or intermittent bolus full enteral feeding. For five days, continuous glucose monitoring (CGM) was utilized, which was achieved through the subcutaneous insertion of a sensor. A total of 27,532 measurements of blood glucose were taken. The mean amplitude of glycemic excursions did not differ between the two cohorts statistically. Continuous feeding resulted in higher positive values, increasing the risk of hypo- and hyperglycemia. Subjects who were small for their gestational age had a higher standard deviation during continuous feeding (p = 0.001). Data suggest that intermittent bolus nutrition is better for glycemic control than continuous nutrition. Nutritional management optimization of preterm infants appears to be critical for long-term health. In the future, CGM may provide a better understanding of the optimal glucose targets for various clinical conditions, allowing for a more personalized approach to management.

Feasibility and Safety of Continuous Glucose Monitoring in Infants at Risk of Hypoglycemia in a Rooming-in Setting

Background:Screening of neonatal hypoglycemia uses currently intermittent blood sampling. Continuous glucose monitoring (CGM) allows for tighter glucose control and better comfort for newborns and parents. CGM has previously been used in intensive care setting or blinded to clinicians. Our pilot study uses CGM in real time in rooming-in setting. Methods: CGM was attached within first two hours of life. Low glucose readings were verified to prevent overtreatment. Pairs of sensor readings and corresponding blood glucose measurements were assessed retrospectively. Neurodevelopmental evaluation was performed at 24 months. Results: 44 infants were enrolled. Three had verified hypoglycemia found due to CGM. No patient was below 2 standard deviations in any components of Bayley scales. Median scores were: Cognitive 100, language 86, motor 94. Conclusion: Use of CGM in a rooming-in environment is safe from clinical and neurodevelopmental point of view. Randomized trials are needed to evaluate superiority in longer term outcomes.

Cerebral Effects of Neonatal Dysglycemia

This article summarizes the available evidence reporting the relationship between perinatal dysglycemia and long-term neurodevelopment. We review the physiology of perinatal glucose metabolism and discuss the controversies surrounding definitions of perinatal dysglycemia. We briefly review the epidemiology of hypoglycemia and hyperglycemia in fetal, preterm, and term infants. We discuss potential pathophysiologic mechanisms contributing to dysglycemia and its effect on neurodevelopment. We highlight current strategies to prevent and treat dysglycemia in the context of neurodevelopmental outcomes. Finally, we discuss areas of future research and the potential role of continuous glucose monitoring.

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.

Continuous glucose monitoring for the prevention of morbidity and mortality in preterm infants

BACKGROUND

Preterm infants are susceptible to hyperglycaemia and hypoglycaemia, which may lead to adverse neurodevelopment. The use of continuous glucose monitoring (CGM) devices might help in keeping glucose levels in the normal range, and reduce the need for blood sampling. However, the use of CGM might be associated with harms in the preterm infant.

OBJECTIVES

To assess the benefits and harms of CGM versus intermittent modalities to measure glycaemia in preterm infants 1. at risk of hypoglycaemia or hyperglycaemia; 2. with proven hypoglycaemia; or 3. with proven hyperglycaemia.

SEARCH METHODS

We searched CENTRAL (2021, Issue 4); PubMed; Embase; and CINAHL in April 2021. We also searched clinical trials databases, conference proceedings, and reference lists of retrieved articles for randomized controlled trials (RCTs) and quasi-RCTs.

SELECTION CRITERIA

We included RCTs and quasi-RCTs comparing the use of CGM versus intermittent modalities to measure glycaemia in preterm infants at risk of hypoglycaemia or hyperglycaemia; with proven hypoglycaemia; or with proven hyperglycaemia.

DATA COLLECTION AND ANALYSIS

We assessed the methodological quality of included trials using Cochrane Effective Practice and Organisation of Care Group (EPOC) criteria (assessing randomization, blinding, loss to follow-up, and handling of outcome data). We evaluated treatment effects using a fixed-effect model with risk ratio (RR) with 95% confidence intervals (CI) for categorical data and mean, standard deviation (SD), and mean difference (MD) for continuous data. We used the GRADE approach to assess the certainty of the evidence.

MAIN RESULTS

We included four trials enrolling 300 infants in our updated review. We included one new study and excluded another previously included study (because the inclusion criteria of the review have been narrowed). We compared the use of CGM to intermittent modalities in preterm infants at risk of hypoglycaemia or hyperglycaemia; however, one of these trials was analyzed separately because CGM was used as a standalone device, without being coupled to a control algorithm as in the other trials. We identified no studies in preterm infants with proven hypoglycaemia or hyperglycaemia.  None of the four included trials reported the neurodevelopmental outcome (i.e. the primary outcome of this review), or seizures. The effect of the use of CGM on mortality during hospitalization is uncertain (RR 0.59, 95% CI 0.16 to 2.13; RD -0.02, 95% CI -0.07 to 0.03; 230 participants; 2 studies; very low-certainty evidence). The certainty of the evidence was very low for all outcomes because of limitations in study design, and imprecision of estimates. One study is ongoing (estimated sample size 60 infants) and planned to be completed in 2022.

AUTHORS' CONCLUSIONS

There is insufficient evidence to determine if CGM affects preterm infant mortality or morbidities.  We are very uncertain of the safety of CGM and the available management algorithms, and many morbidities remain unreported. Preterm infants at risk of hypoglycaemia or hyperglycaemia were enrolled in all four included studies. No studies have been conducted in preterm infants with proven hypoglycaemia or hyperglycaemia. Long-term outcomes were not reported. Events of necrotizing enterocolitis, reported in the study published in 2021, were lower in the CGM group. However, the effect of CGM on this outcome remains very uncertain. Clinical trials are required to determine the most effective CGM and glycaemic management regimens in preterm infants before larger studies can be performed to assess the efficacy of CGM for reducing mortality, morbidity, and long-term neurodevelopmental impairments.

Effect of Prophylactic Dextrose Gel on Continuous Measures of Neonatal Glycemia: Secondary Analysis of the Pre-hPOD Trial

OBJECTIVE

To determine the effects of different doses of prophylactic dextrose gel on glycemic stability assessed using continuous glucose monitoring in the first 48 hours when given to babies at risk of neonatal hypoglycemia.

STUDY DESIGN

Continuous glucose monitoring was undertaken for the first 48 hours in 133 infants at risk of hypoglycemia who participated in the pre-hPOD randomized dosage trial of dextrose gel prophylaxis.

RESULTS

Low glucose concentrations were detected in 41% of infants by blood glucose monitoring and 68% by continuous interstitial glucose monitoring. The mean ± SD duration of low interstitial glucose concentrations was 295 ± 351 minutes in the first 48 hours. Infants who received any dose of dextrose gel seemed to be less likely than those who received placebo gel to experience low glucose concentrations (<47 mg/dL [2.6 mmol/L]; P = .08), particularly if they received a single dose of 200 mg/kg (relative risk, 0.70; 95% CI, 0.50-0.10; P = .049). They also spent a greater proportion of time in the central glucose concentration range of 54-72 mg/dL (3-4 mmol/L) (any dose, mean ± SD, 58.2 ± 20.3%; placebo, 50.0 ± 21.9%; mean difference, 8.20%; 95% CI, 0.43-15.9%; P = .038). Dextrose gel did not increase recurrent or severe episodes of low glucose concentrations and did not increase the peak glucose concentration. These effects were similar for all trial dosages.

CONCLUSIONS

Low glucose concentrations were common in infants at risk of hypoglycemia despite blood glucose monitoring and treatment. Prophylactic dextrose gel reduced the risk of hypoglycemia without adverse effects on glucose stability.

Safety and feasibility of a factory-calibrated continuous glucose monitoring system in term and near-term infants at risk of hypoglycemia

Objective

Hypoglycemia increases the risk of adverse neurological outcomes in neonates. Adequate glucose monitoring requires repetitive and painful blood sampling. We aimed to evaluate the feasibility and accuracy of a continuous glucose monitoring system (CGMS) using factory-calibrated sensors to improve glucose monitoring and decrease the frequency of blood samples in neonates.

Material and Methods

A methodological study was conducted to investigate a correlation of CGMS values with blood glucose measurements.

Results

Factory-calibrated CGMS sensors were placed on 21 infants at risk of hypoglycemia after delivery. CGMS values were compared with blood glucose concentrations. Thirty-seven pairs of CGMS and blood glucose values were obtained. There was a good correlation between CGMS and blood glucose values (R=0.67, p<0.01) with a mean difference (2 standard deviations) of 9.78 (-24.68 to 44.25) mg/dL. The mean differences at <3 hours and ≥3 hours after sensor placement were 17.35 (-4.54 to 39.21) mg/dL and 0.88 (-37.62 to 39.38) mg/dL, respectively. CGMS values were significantly higher than blood glucose concentration at <3 hours after sensor placement (p<0.01), whereas no significant differences in glucose values were observed between the CGMS and blood glucose values at ≥3 hours after sensor placement (p=0.852).

Conclusion

The factory-calibrated CGMS was a safe and feasible modality for glucose monitoring. However, it has a tendency to overestimate the blood glucose concentrations. Therefore, this system should be used cautiously for neonates at risk of hypoglycemia, especially within 3 hours after sensor placement.

GLYCEMIC VARIABILITY IS ASSOCIATED WITH TREATMENT REQUIRING RETINOPATHY OF PREMATURITY: A Case-Control Study

PURPOSE

To assess the association between glycemic variability (GV) and Type 1 retinopathy of prematurity (ROP) in infants with birth weights of less than 1,251 g.

METHODS

A case-control study of infants with birth weights of less than 1,251 g who developed Type 1 ROP (n = 20) was conducted. Controls had a less severe ROP or no eye disease and were individually matched for gestational age and birth weight (n = 40). Odds ratios of ROP were calculated based on multiple factors including oxygen exposure, respiratory support, incidence of hyperglycemia, and GV. For glucose measurements, a continuous glucose monitoring system was used.

RESULTS

There were no significant differences in gender, antenatal steroid administration, severity of illness, and Apgar score. Univariate analyses suggest increased risk for the development of Type 1 ROP based on incidence of intraventricular hemorrhage Grade 3 or 4 (P = 0.048), duration of oxygen exposure (P = 0.003), incidence of hyperglycemia over 150 mg/dL (P = 0.01), and GV according to significantly higher SD (P = 0.002), coefficient of variation (P = 0.001), and mean amplitude of glucose excursion (P = 0.008). Using a multiple regression model, increased risk of Type 1 ROP was only found to be associated with duration of oxygen exposure and higher GV.

CONCLUSION

Our study demonstrates a relationship between GV and the development of severe ROP.

Monitoring the Frequency and Duration of Hypoglycemia in Preterm Infants and Identifying Associated Factors

Hypoglycemia is common in very low birth weight neonates and may have adverse effects. Material and Method: Sixty preterm infants were monitored using continuous glucose monitoring (CGMS) and capillary techniques during the first week of life. Hypoglycemia was defined as glucose ≤47 mg/dL (≤2.6 mmol/L). Results: Hypoglycemic episodes were detected in 41.66% (95% CI: 29.07-55.12). In 69.64% the duration was greater than thirty minutes, in 26.78% (95% CI: 15.83-40.3) hypoglycemia exceeded two hours. Hypoglycemia was observed most frequently during the first 48 hours. In 35.7%, hypoglycemia was not detected with capillary tests. The agreement between the two techniques was good (r = 0.77, p < 0.001), Hypoglycemia was associated with a lower birth weight (OR: 0.99, p = 0.06). Conclusions: Hypoglycemia is frequent with significant duration in very low birth weight neonates. CGMS could be considered for use in these neonates to improve their glycemic control and prevent the associated morbidity.

Real-time continuous glucose monitoring in preterm infants (REACT): an international, open-label, randomised controlled trial

BACKGROUND

Hyperglycaemia and hypoglycaemia are common in preterm infants and have been associated with increased risk of mortality and morbidity. Interventions to reduce risk associated with these exposures are particularly challenging due to the infrequent measurement of blood glucose concentrations, with the potential of causing more harm instead of improving outcomes for these infants. Continuous glucose monitoring (CGM) is widely used in adults and children with diabetes to improve glucose control, but has not been approved for use in neonates. The REACT trial aimed to evaluate the efficacy and safety of CGM in preterm infants requiring intensive care.

METHODS

This international, open-label, randomised controlled trial was done in 13 neonatal intensive care units in the UK, Spain, and the Netherlands. Infants were included if they were within 24 h of birth, had a birthweight of 1200 g or less, had a gestational age up to 33 weeks plus 6 days, and had parental written informed consent. Infants were randomly assigned (1:1) to real-time CGM or standard care (with masked CGM for comparison) using a central web randomisation system, stratified by recruiting centre and gestational age (<26 or ≥26 weeks). The primary efficacy outcome was the proportion of time sensor glucose concentration was 2·6-10 mmol/L for the first week of life. Safety outcomes related to hypoglycaemia (glucose concentrations <2·6 mmol/L) in the first 7 days of life. All outcomes were assessed on the basis of intention to treat in the full analysis set with available data. The study is registered with the International Standard Randomised Control Trials Registry, ISRCTN12793535.

FINDINGS

Between July 4, 2016, and Jan 27, 2019, 182 infants were enrolled, 180 of whom were randomly assigned (85 to real-time CGM, 95 to standard care). 70 infants in the real-time CGM intervention group and 85 in the standard care group had CGM data and were included in the primary analysis. Compared with infants in the standard care group, infants managed using CGM had more time in the 2·6-10 mmol/L glucose concentration target range (mean proportion of time 84% [SD 22] vs 94% [11]; adjusted mean difference 8·9% [95% CI 3·4-14·4]), equivalent to 13 h (95% CI 5-21). More infants in the standard care group were exposed to at least one episode of sensor glucose concentration of less than 2·6 mmol/L for more than 1 h than those in the intervention group (13 [15%] of 85 vs four [6%] of 70). There were no serious adverse events related to the use of the device or episodes of infection.

INTERPRETATION

Real-time CGM can reduce exposure to prolonged or severe hyperglycaemia and hypoglycaemia. Further studies using CGM are required to determine optimal glucose targets, strategies to obtain them, and the potential effect on long-term health outcomes.

FUNDING

National Institute for Health Research Efficacy and Mechanisms Evaluation Programme.

Interventions to minimize blood loss in very preterm infants-A systematic review and meta-analysis

Blood loss in the first days of life has been associated with increased morbidity and mortality in very preterm infants. In this systematic review we included randomized controlled trials comparing the effects of interventions to preserve blood volume in the infant from birth, reduce the need for sampling, or limit the blood sampled. Mortality and major neurodevelopmental disabilities were the primary outcomes. Included studies underwent risk of bias-assessment and data extraction by two review authors independently. We used risk ratio or mean difference to evaluate the treatment effect and meta-analysis for pooled results. The certainty of evidence was assessed using GRADE. We included 31 trials enrolling 3,759 infants. Twenty-five trials were pooled in the comparison delayed cord clamping or cord milking vs. immediate cord clamping or no milking. Increasing placental transfusion resulted in lower mortality during the neonatal period (RR 0.51, 95% CI 0.26 to 1.00; participants = 595; trials = 5; I2 = 0%, moderate certainty of evidence) and during first hospitalization (RR 0.70, 95% CI 0.51, 0.96; 10 RCTs, participants = 2,476, low certainty of evidence). The certainty of evidence was very low for the other primary outcomes of this review. The six remaining trials compared devices to monitor glucose levels (three trials), blood sampling from the umbilical cord or from the placenta vs. blood sampling from the infant (2 trials), and devices to reintroduce the blood after analysis vs. conventional blood sampling (1 trial); the certainty of evidence was rated as very low for all outcomes in these comparisons. Increasing placental transfusion at birth may reduce mortality in very preterm infants; However, extremely limited evidence is available to assess the effects of other interventions to reduce blood loss after birth. In future trials, infants could be randomized following placental transfusion to different blood saving approaches. Trial registration: PROSPERO CRD42020159882.

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.

Accuracy of continuous glucose monitoring in preterm infants: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

Continuous glucose monitoring (CGM) could be a valuable instrument for measurement of glucose concentration in preterm neonate. We undertook a systematic review and meta-analysis to compare the diagnostic accuracy of CGM devices to intermittent blood glucose evaluation methods for the detection of hypoglycaemic or hypoglycaemic events in preterm infants.

DATA SOURCES

A structured electronic database search was performed for studies that assessed the accuracy of CGM against any intermittent blood glucose testing methods in detecting episodes of altered glycaemia in preterm infants. No restrictions were used. Three review authors screened records and included studies.

DATA EXTRACTION

Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. From individual patient data (IPD), sensitivity and specificity were determined using predefined thresholds. The mean absolute relative difference (MARD) of the studied CGM devices was assessed and if those satisfied the accuracy requirements (EN ISO 15197). IPD datasets were meta-analysed using a logistic mixed-effects model. A bivariate model was used to estimate the summary receiver operating characteristic curve (ROC) curve and extract the area under the curve (AUC). The overall level of certainty of the evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation.

RESULTS

Among 4481 records, 11 were included. IPD datasets were obtained for five studies. Only two of the studies showed an MARD lower than 10%, with none of the five CGM devices studied satisfying the European Union (EU) ISO 15197 requirements. Pooled sensitivity and specificity of CGM devices for hypoglycaemia were 0.39 and 0.99, whereas for hyperglycaemia were 0.87 and 0.99, respectively. The AUC was 0.70 and 0.86, respectively. The certainty of the evidence was considered as low to moderate. Limitations primarily related to the lack of representative population, reference standard and CGM device.

CONCLUSIONS

CGM devices demonstrated low sensitivity for detecting hypoglycaemia in preterm infants, however, provided high accuracy for detection of hyperglycaemia.

PROSPERO REGISTRATION NUMBER

CRD42020152248.

Continuous glucose monitoring for the prevention of morbidity and mortality in preterm infants

BACKGROUND

Preterm infants are susceptible to hyperglycemia and hypoglycemia, conditions which may lead to adverse neurodevelopment. The use of continuous glucose monitoring devices (CGM) might help keeping glucose levels in the normal range, and reduce the need for blood sampling. However, the use of CGM might be associated with harms in the preterm infant.

OBJECTIVES

Objective one: to assess the benefits and harms of CGM alone versus standard method of glycemic measure in preterm infants. Objective two: to assess the benefits and harms of CGM with automated algorithm versus standard method of glycemic measure in preterm infants. Objective three: to assess the benefits and harms of CGM with automated algorithm versus CGM without automated algorithm in preterm infants.

SEARCH METHODS

We adopted the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2020, Issue 9), in the Cochrane Library; MEDLINE via PubMed (1966 to 25 September 2020); Embase (1980 to 25 September 2020); and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (1982 to 25 September 2020). We also searched clinical trials databases, conference proceedings, and reference lists of retrieved articles for randomized controlled trials and quasi-randomized trials.

SELECTION CRITERIA

Randomized controlled trials (RCTs) and quasi-RCTs in preterm infants comparing: 1) the use of CGM versus intermittent modalities to measure glycemia (comparison 1); or CGM associated with prespecified interventions to correct hypoglycemia or hyperglycemia versus CGM without such prespecified interventions (comparison 2).

DATA COLLECTION AND ANALYSIS

We assessed the methodological quality of included trials using Cochrane Effective Practice and Organisation of Care Group (EPOC) criteria (assessing randomization, blinding, loss to follow-up, and handling of outcome data). We evaluated treatment effects using a fixed-effect model with risk ratio (RR) for categorical data and mean, standard deviation (SD), and mean difference (MD) for continuous data. We used the GRADE approach to assess the certainty of the evidence.

MAIN RESULTS

Four trials enrolling 138 infants met our inclusion criteria. Investigators in three trials (118 infants) compared the use of CGM to intermittent modalities (comparison one); however one of these trials was analyzed separately because CGM was used as a standalone device, without being coupled to a control algorithm like in the other trials. A fourth trial (20 infants) assessed CGM with an automated algorithm versus CGM with a manual algorithm. None of the four included trials reported the neurodevelopmental outcome, i.e. the primary outcome of this review. Within comparison one, the certainty of the evidence on the use of CGM on mortality during hospitalization is very uncertain (typical RR 3.00, 95% CI 0.13 to 70.30; typical RD 0.04, 95% CI -0.06 to 0.14; 50 participants; 1  study; very low certainty). The number of hypoglycemic episodes was reported in two studies with conflicting data. The number of hyperglycemic episodes was reported in one study (typical MD -1.40, 95% CI -2.84 to 0.04; 50 participants; 1 study). The certainty of the evidence was very low for all outcomes because of limitations in study design, and imprecision of estimates.  Three studies are ongoing.

AUTHORS' CONCLUSIONS

There is insufficient evidence to determine if CGM improves preterm infant mortality or morbidities. Long-term outcomes were not reported. Clinical trials are required to determine the most effective CGM and glycemic management regimens in preterm infants before larger studies can be performed to assess the efficacy of CGM  for reducing mortality, morbidity and long-term neurodevelopmental impairments. The absence of CGM labelled for neonatal use is still a major limit in its use as well as the absence of dedicated neonatal devices.

Risk factors for postoperative hyperglycemia in neonates

OBJECTIVE

Postoperative hyperglycemia has been shown to be associated with higher morbidity and mortality in pediatric patients. Data on risk factors for neonatal patients is limited. The objective of this study was to identify pre- and intraoperative risk factors associated with postoperative glucose in neonates.

METHODS

We conducted a retrospective cohort study of neonates after surgical procedures between January and December 2016 in a quaternary neonatal intensive care unit. The primary outcome was hyperglycemia defined as serum glucose ≥8.3 mmol/L during the first 4 hours postoperatively. Secondary outcomes included death and length of stay. We assessed the association of risk factors with the postoperative glucose.

RESULTS

In total, 206 surgical procedures (171 patients) were evaluated, among which 178 had serum glucose values during the first 4 hours postoperatively available. The incidence of hyperglycemia was 54% (n = 96). The median (IQR) glucose during the first 4 hours in NICU was 8.4 (6.52-10.65) mmol/L. Risk factors for postoperative hyperglycemia were intraoperative glucose infusion rate (GIR) and gestational age. There was a non-linear relationship between gestational age and postoperative hyperglycemia. Mortality occurred in 6 (7%) in the no-hyperglycemia group and 3 (3%) in the hyperglycemia group (p = 0.31).

CONCLUSIONS

Among the risk factors, intraoperative GIR was identified as a modifiable factor that can reduce postoperative hyperglycemia. A non-linear relationship of gestational age with postoperative glucose provides new insights that may help advance our understanding of the complex mechanisms of glucose homeostasis in neonates.

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.

The screening and management of newborns at risk for low blood glucose

Hypoglycemia in the first hours to days after birth remains one of the most common conditions facing practitioners across Canada who care for newborns. Many cases represent normal physiologic transition to extrauterine life, but another group experiences hypoglycemia of longer duration. This statement addresses key issues for providers of neonatal care, including the definition of hypoglycemia, risk factors, screening protocols, blood glucose levels requiring intervention, and managing care for this condition. Screening, monitoring, and intervention protocols have been revised to better identify, manage, and treat infants who are at risk for persistent, recurrent, or severe hypoglycemia. The role of dextrose gels in raising glucose levels or preventing more persistent hypoglycemia, and precautions to reduce risk for recurrence after leaving hospital, are also addressed. This statement differentiates between approaches to care for hypoglycemia during the 'transitional' phase-the first 72 hours post-birth-and persistent hypoglycemia, which occurs or presents for the first time past that point.

Le dépistage et la prise en charge des nouveau-nés à risque d’hypoglycémie

L’hypoglycémie entre les premières heures et les premiers jours suivant la naissance demeure l’une des principales affections qu’observent les praticiens du Canada qui s’occupent de nouveau-nés. Bien des cas vivent une transition physiologique normale à la vie extra-utérine, mais un groupe présente une hypoglycémie pendant une plus longue période. Le présent document de principes expose les principaux enjeux auxquels sont exposés les dispensateurs de soins néonatals, y compris la définition d’hypoglycémie, les facteurs de risque, les protocoles de dépistage, les valeurs de glycémie nécessitant une intervention et la gestion des soins pour cette affection. Les auteurs passent en revue le dépistage, la surveillance et les protocoles d’intervention pour mieux distinguer, prendre en charge et traiter les nouveau-nés à risque d’hypoglycémie persistante, récurrente ou marquée. Ils abordent également le rôle des gels de dextrose pour accroître la glycémie ou prévenir une hypoglycémie plus persistante, de même que les précautions à prendre pour réduire les risques de récurrence après le congé de l’hôpital. Le présent document de principes distingue les approches des soins de l’hypoglycémie pendant la « phase de transition » (les 72 premières heures de vie) de celles de l’hypoglycémie persistante, qui se manifeste ou est constatée pour la première fois après cette période.

Reliability of real-time continuous glucose monitoring in infants

BACKGROUND

Neonatal hypoglycemia is a common and treatable risk factor for neurological impairment. Real-time continuous glucose monitoring (RT-CGM) can show glucose concentration in real time. Using an RT-CGM alarm, physicians can be alerted and intervene in hypoglycemia. No reports, however, have evaluated the reliability of RT-CGM at low glucose levels in infants. This study therefore investigated the difference between blood glucose (BG) and RT-CGM sensor data at low glucose levels and assessed the optimum method of using a hypoglycemic alarm in infants.

METHODS

We enrolled infants whose glycemic management was difficult. We calculated the mean absolute difference (MAD) and mean absolute relative difference (MARD) between BG and RT-CGM sensor data. We compared the MAD and MARD between the low BG fluctuation and high BG fluctuation groups.

RESULTS

We used RT-CGM for 12 patients (29 times) and investigated 448 pairs of BG and RT-CGM sensor data. The MAD between these pairs was 9.3 ± 8.9 mg/dL, and the MARD was 11.5%. The MAD at low glucose was 7.7 ± 6.0 mg/dL, and the MARD was 16.2%. The MAD and MARD were 6.8 ± 5.4 mg/dL and 7.8% in the low fluctuation group and 10.1 ± 9.5 mg/dL and 12.7% in the high fluctuation group, respectively.

CONCLUSIONS

The difference between BG and RT-CGM sensor data changes with the degree of fluctuation in BG. When physicians set the hypoglycemic alarm, consideration of this difference and a change in the alarm setting according to the degree of fluctuation in BG may be useful.

Hyperglycemia and Glucose Variability Are Associated with Worse Brain Function and Seizures in Neonatal Encephalopathy: A Prospective Cohort Study

OBJECTIVES

To investigate how glucose abnormalities correlate with brain function on amplitude-integrated electroencephalography (aEEG) in infants with neonatal encephalopathy.

STUDY DESIGN

Neonates born at full term with encephalopathy were enrolled within 6 hours of birth in a prospective cohort study at a pediatric academic referral hospital. Continuous interstitial glucose monitors and aEEG were placed soon after birth and continued for 3 days. Episodes of hypoglycemia (≤50 mg/dL; ≤2.8 mmol/L) and hyperglycemia (>144 mg/dL; >8.0 mmol/L) were identified. aEEG was classified in 6-hour epochs for 3 domains (background, sleep-wake cycling, electrographic seizures). Generalized estimating equations assessed the relationship of hypo- or hyperglycemia with aEEG findings, adjusting for clinical markers of hypoxia-ischemia (Apgar scores, umbilical artery pH, and base deficit).

RESULTS

Forty-five infants (gestational age 39.5 ± 1.4 weeks) were included (24 males). During aEEG monitoring, 16 episodes of hypoglycemia were detected (9 infants, median duration 77.5, maximum 220 minutes) and 18 episodes of hyperglycemia (13 infants, median duration 237.5, maximum 3125 minutes). Epochs of hypoglycemia were not associated with aEEG changes. Compared with epochs of normoglycemia, epochs of hyperglycemia were associated with worse aEEG background scores (B 1.120, 95% CI 0.501-1.738, P < .001), less sleep-wake cycling (B 0.587, 95% CI 0.417-0.757, P < .001) and more electrographic seizures (B 0.433, 95% CI 0.185-0.681, P = .001), after adjusting for hypoxia-ischemia severity.

CONCLUSIONS

In neonates with encephalopathy, epochs of hyperglycemia were temporally associated with worse global brain function and seizures, even after we adjusted for hypoxia-ischemia severity. Whether hyperglycemia causes neuronal injury or is simply a marker of severe brain injury requires further study.

A Feasibility Study to Detect Neonatal Hypoglycemia in Infants of Diabetic Mothers Using Real-Time Continuous Glucose Monitoring

BACKGROUND

Infants born to mothers with diabetes commonly experience asymptomatic hypoglycemia after birth. Continuous glucose monitors (CGM) can detect asymptomatic hypoglycemia in this population without the need for painful glucose checks.

METHODS

Infants born after 34 weeks of gestation to mothers with diabetes had a CGM placed after birth. One group of infants was remotely monitored in real-time by research staff during the hospitalization, whereas another group wore a blinded CGM. In both groups, hospital standard-of-care (SOC) glucose checks were performed. Clinical staff and families were blinded to CGM data. For CGM readings <45 mg/dL, research staff requested a verification blood glucose (BG) using the point-of-care glucometer.

RESULTS

Sixteen infants were studied; 4 with a blinded CGM and 12 with remote monitoring (RM). When there were confirmatory hospital glucometer readings, the sensitivity of the CGM to detect hypoglycemia was 86% and the specificity was 91%. The positive predictive value was 55% and the negative predictive value was 98%. In the full cohort, hypoglycemia (<45 mg/dL) was confirmed in 12 of 16 infants with 30 events at <12 hours of life (HOL), 3 events between 12 and 24 HOL, and 1 event at >48 HOL. In the RM group, CGM detected hypoglycemia five times when the infant was not due for a BG check based on the SOC. Overall, the CGM detected five false-positive alerts and six true-positive alerts for hypoglycemia. Only one hypoglycemic episode was missed by CGM in the RM group. Barriers to recruitment included fear of pain with glucose checks, concerns with CGM use, satisfaction with the hospital SOC, personal reasons independent of the study, and lack of interest in participating in research.

CONCLUSIONS

Although there were barriers to recruitment and retention in the study, we conclude that CGM can provide added benefit for detecting hypoglycemia when used early after birth.

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.

A Feasibility Study of Paired Continuous Glucose Monitoring Intrapartum and in the Newborn in Pregnancies Complicated by Type 1 Diabetes

AIM

To describe the continuous glucose monitoring (CGM) profiles of type 1 diabetes (T1D) offspring in the early neonatal period and its association with maternal intrapartum glucose control.

METHODS

A prospective observational study of T1D pregnant women and their neonatal offspring. Women had a CGM sensor inserted 2-3 days before delivery. Infants had a masked CGM sensor inserted as soon as possible after delivery. Maternal glycemic outcomes were time-in-target (70-140 mg/dL [3.9-7.8 mmol/L]), hyperglycemia >140 mg/dL (7.8 mmol/L), and mean CGM glucose during the 24 h preceding delivery. Neonatal outcomes included lowest recorded blood glucose concentration, and CGM measures (glucose <47 mg/dL [2.6 mmol/L], time-in-target (47-144 mg/dL [2.6-8.0 mmol/L]), glucose standard deviation [SD]) during the first 72 h of life.

RESULTS

Data were available for 16 mother-infant pairs. Mothers had a mean age (SD) 32.3 (4.3) years, T1D duration 17.6 (6.8) years, first antenatal glycated hemoglobin 7.4 (0.8)% (57 [8.5] mmol/mol). In the 24 h preceding delivery, mothers spent mean (SD) 72 (20)% time-in-target (70-140 mg/dL [3.9-7.8 mmol/L]), 19 (15)% time >140 mg/dL (7.8 mmol/L), and 9 (9)% time <70 mg/dL (3.9 mmol/L) with mean (SD) CGM glucose 113 (9) mg/dL (6.3 [0.7] mmol/L). Fifteen infants (93.8%) had ≥1 blood glucose concentration <47 mg/dL (2.6 mmol/L), and five had ≥1 blood glucose concentration <18 mg/dL (1.0 mmol/L). The mean infant CGM glucose on days 1, 2, and 3 of life was 63 (14), 67 (13), 76 (11) mg/dL (3.5 [0.8], 3.7 [0.7], and 4.2 [0.6] mmol/L). Four infants (25%) spent >50% time with CGM glucose levels <47 mg/dL (2.6 mmol/L) on day 1.

CONCLUSIONS

CGM detected widespread neonatal hypoglycemia, even among mothers with good intrapartum glucose control.

Procedural Pain during Insertion of a Continuous Glucose Monitoring Device in Preterm Infants

Procedural pain was compared between the insertion of a continuous glucose monitoring sensor and heel stick using the Premature Infant Pain Profile in a single-blinded controlled trial in preterm infants (≤32 weeks of gestation or birth weight ≤1500 g) (ClinicalTrials.govNCT02583776). Continuous glucose monitoring insertion was associated with lower pain scores compared with the heel stick.

Continuous glucose monitoring (CGM) in very low birth weight newborns needing parenteral nutrition: validation and glycemic percentiles

Background

Continuous glucose monitoring using subcutaneous sensors is useful in the management of glucose control in neonatal intensive care. We evaluated feasibility and reliability of a continuous glucose monitoring system in a population of very low birth weight neonates needing parenteral nutrition. Moreover, we presented percentiles of glycemia of the studied population.

Methods

Very low birth weight neonates were enrolled within 24 h from birth. An ENLITE sensor connected to a continuous glucose monitoring system was inserted and maintained for at least 72 h. Data obtained with the continuous glucose monitoring system and with a glucometer were compared. Calibration was performed every 12 h.

Results

Twenty-three patients (9 males) were included. Median gestational age was 28 weeks (range 23–30) and median birth weight was 860 g (range 500–1092). A total of 299 paired glucose values were obtained. Modified Clarke Error Grid criteria for clinical significance were met. 74 and 33 episodes of hypoglycemia and hyperglycemia were detected, respectively. 31,329 values of glycemia were analyzed and the percentiles calculated.

Conclusions

This continuous glucose monitoring system is safe and accurate. It allows increasing the detection of hypo- and hyper-glycaemia episodes and it could be routinely used in the management of glucose infusion in very low birth weight neonates under total parenteral nutrition.

Neonatal hypoglycemia: continuous glucose monitoring

PURPOSE OF REVIEW

Continuous glucose monitoring (CGM) is increasingly used in the management of diabetes in children and adults, but there are few data regarding its use in neonates. The purpose of this article is to discuss the potential benefits and limitations of CGM in neonates.

RECENT FINDINGS

Smaller electrodes in new sensors and real-time monitoring have made CGM devices more approachable for neonatal care. CGM is well tolerated in infants including very low birth weight babies, and few if any local complications have been reported. Use of CGM in newborns may reduce the frequency of blood sampling and improve glycemic stability, with more time spent in the euglycemic range. However, CGM may also lead to more intervention, with potential adverse effects on outcomes. More information is also needed about reliability, calibration and interpretation of CGM in the neonate.

SUMMARY

Although the use of CGM in neonates appears to be well tolerated, feasible and has been associated with better glycemic status, there is not yet any evidence of improved clinical outcomes. Clinical utility of CGM should be demonstrated in randomized trials prior to its introduction into regular neonatal care.

Fluctuation of blood glucose levels in an infant with an ileostomy on continuous glucose monitoring: A case report

Infants with an ileostomy can be at high risk of hypoglycemia because of inadequate nutritional intake; however, there are no reports investigating blood glucose (BG) in infants with ileostomy. We experienced a case of an extremely low birth weight infant who was born at 24 wk of gestation and weighted 623 g. He received an ileostomy because of an intestinal perforation. After the ileostomy, he had recurrent hypoglycemia. Continuous glucose monitoring showed fluctuation of BG levels (postprandial BG elevations and subsequent declines) and non-fasting hypoglycemia, which were undetectable with intermittent fasting BG measurement. The fluctuation of BG levels and non-fasting hypoglycemia improved after closure of the ileostomy. Patients with ileostomy may present with hypoglycemia that is undetectable with intermittent fasting BG measurement. In this case, continuous glucose monitoring was very useful for detecting fluctuation of BG levels and hypoglycemic episodes. Therefore, we recommend that continuous glucose monitoring be performed in infants with an ileostomy to confirm whether they have hypoglycemia or a fluctuation in BG levels. Further studies on the postprandial dynamics of various hormones in infants with ileostomy are required.

Preterm Glycosuria - New Data from a Continuous Glucose Monitoring System

BACKGROUND

Careful control of glucose homeostasis is essential for infants with very low birth weight (VLBW). In clinical practice, blood and urine glucose levels are monitored; however, their correlation has not been fully investigated in VLBW infants.

OBJECTIVES

To evaluate the correlation between interstitial fluid glucose concentration (ISFG), glycosuria, and urine output among VLBW infants through continuous glucose monitoring (CGM).

METHODS

A prospective, single-center, open cohort study enrolled 74 VLBW infants with a mean birth weight of 1,066 g. CGM (Guardian Real-Time CGM®; Medtronic, Northridge, CA, USA) was used to measure glucose. The urine output was calculated using 4-hour intervals. Reagent strips were used for semiquantitative measurement of glycosuria.

RESULTS

The CGM delivered 102,334 glucose measurements. 2,684 urine samples were checked for glycosuria, of which 92.06% remained negative. Corresponding glycemia in samples without glycosuria remained normoglycemic (median 103 mg/dL; 10-90th percentile 80-144 mg/dL). The median glucose concentrations for samples in ascending glycosuria categories 1+, 2+, 3+, and 4+ were 152, 181, 214, and 222 mg/dL, respectively. A moderate correlation between ISFG and urine output was found for categories ≥1+ (rs = 0.56; 95% confidence interval 0.42-0.68; p < 0.001). The urine output was significantly lower when glycosuria was absent (p < 0.05). Polyuria was observed only in glycosuria 4+ (median urine output 9.9; interquartile range 7.4-12.2 mL/kg/h).

CONCLUSIONS

The renal glucose threshold in VLBW infants is between 150 and 180 mg/dL. A negative result for glycosuria is a reliable screening test to exclude hyperglycemia. Occurrence of glycosuria ≥1+ is an indication to test blood glucose.

Primum non nocere: earlier cessation of glucose monitoring is possible

Newborns are at relatively high risk for developing hypoglycaemia in the first 24 h after birth. Well-known risk factors are prematurity, small for gestational age (SGA) or large for gestational age (LGA), and maternal pre-existent or gestational diabetes mellitus. Prolonged hypoglycaemia is associated with poor neurodevelopmental outcomes; hence, prevention through proper monitoring and treatment is important. Given the ongoing debate concerning frequency and duration of screening for neonatal hypoglycaemia, therefore, we investigated the frequency and duration of glucose monitoring safe to discover neonatal hypoglycaemia in different risk groups. Data of newborns at risk for hypoglycaemia were retrospectively collected and analysed. Blood glucose concentrations were measured 1, 3, 6, 12, and 24 h after birth. Moderate hypoglycaemia was defined as a blood glucose concentration of < 2.2 mM and severe hypoglycaemia as a concentration of < 1.5 mM. Of 1570 newborns, 762 (48.5%) had at least one episode of hypoglycaemia in the first 24 h after birth; 30.6% of them had severe hypoglycaemia (all in the first 9 h after birth). Only three SGA and two LGA newborns had a first moderate asymptomatic hypoglycaemic episode beyond 12 h after birth. The incidence of hypoglycaemia increased with accumulation of multiple risk factors.

CONCLUSION

Safety of limiting the monitoring to 12 h still has to be carefully evaluated in the presence of SGA or LGA newborns; however, our results suggest that 12 h is enough for late preterm newborns (> 34 weeks) and maternal diabetes. What is Known: • Newborns are at relatively high risk for developing hypoglycaemia and such hypoglycaemia is associated with adverse neurodevelopmental outcomes. • Proper glucose monitoring and prompt treatment in case of neonatal hypoglycaemia are necessary. What is New: • Glucose monitoring 12 h after birth is proficient for most newborns at risk. • Maternal diabetes leads to the highest risk of early neonatal hypoglycaemia and newborns with more than one risk factor are at increased risk of hypoglycaemia.

Hypoglycemia: When to Treat?

Hypoglycemia is the most common metabolic disorder encountered in neonates. The definition of hypoglycemia as well as its clinical significance and management remain controversial. Most cases of neonatal hypoglycemia are transient, respond readily to treatment, and are associated with an excellent prognosis. Persistent hypoglycemia is more likely to be associated with abnormal endocrine conditions, such as hyperinsulinemia, as well as possible neurologic sequelae. Manifestations of hypoglycemia include seizures which can result in noteworthy neuromorbidity in the long haul. Thus, hypoglycemia constitutes a neonatal emergency which requires earnest analytic assessment and prompt treatment. In this review, we have tried to cover the pathophysiology, the screening protocol for high-risk babies, management, long-term neurologic sequelae associated with neonatal hypoglycemia, with evidence-based answers wherever possible, and our own practices.

Continuous glucose monitoring in neonates: a review

Continuous glucose monitoring (CGM) is well established in the management of diabetes mellitus, but its role in neonatal glycaemic control is less clear. CGM has provided important insights about neonatal glucose metabolism, and there is increasing interest in its clinical use, particularly in preterm neonates and in those in whom glucose control is difficult. Neonatal glucose instability, including hypoglycaemia and hyperglycaemia, has been associated with poorer neurodevelopment, and CGM offers the possibility of adjusting treatment in real time to account for individual metabolic requirements while reducing the number of blood tests required, potentially improving long-term outcomes. However, current devices are optimised for use at relatively high glucose concentrations, and several technical issues need to be resolved before real-time CGM can be recommended for routine neonatal care. These include: 1) limited point accuracy, especially at low or rapidly changing glucose concentrations; 2) calibration methods that are designed for higher glucose concentrations of children and adults, and not for neonates; 3) sensor drift, which is under-recognised; and 4) the need for dynamic and integrated metrics that can be related to long-term neurodevelopmental outcomes. CGM remains an important tool for retrospective investigation of neonatal glycaemia and the effect of different treatments on glucose metabolism. However, at present CGM should be limited to research studies, and should only be introduced into routine clinical care once benefit is demonstrated in randomised trials.

Continuous Glucose Monitoring in Very Preterm Infants: A Randomized Controlled Trial

BACKGROUND AND OBJECTIVES

Impaired glucose control in very preterm infants is associated with increased morbidity, mortality, and poor neurologic outcome. Strategies based on insulin titration have been unsuccessful in achieving euglycemia in absence of an increase in hypoglycemia and mortality. We sought to assess whether glucose administration guided by continuous glucose monitoring (CGM) is more effective than standard of care blood glucose monitoring in maintaining euglycemia in very preterm infants.

METHODS

Fifty newborns ≤32 weeks' gestation or with birth weight ≤1500 g were randomly assigned (1:1) within 48-hours from birth to receive computer-guided glucose infusion rate (GIR) with or without CGM. In the unblinded CGM group, the GIR adjustments were driven by CGM and rate of glucose change, whereas in the blinded CGM group the GIR was adjusted by using standard of care glucometer on the basis of blood glucose determinations. Primary outcome was percentage of time spent in euglycemic range (72-144 mg/dL). Secondary outcomes were percentage of time spent in mild (47-71 mg/dL) and severe (<47 mg/dL) hypoglycemia; percentage of time in mild (145-180 mg/dL) and severe (>180 mg/dL) hyperglycemia; and glucose variability.

RESULTS

Neonates in the unblinded CGM group had a greater percentage of time spent in euglycemic range (median, 84% vs 68%, P < .001) and decreased time spent in mild (P = .04) and severe (P = .007) hypoglycemia and in severe hyperglycemia (P = .04) compared with the blinded CGM group. Use of CGM also decreased glycemic variability (SD: 21.6 ± 5.4 mg/dL vs 27 ± 7.2 mg/dL, P = .01; coefficient of variation: 22.8% ± 4.2% vs 27.9% ± 5.0%; P < .001).

CONCLUSIONS

CGM-guided glucose titration can successfully increase the time spent in euglycemic range, reduce hypoglycemia, and minimize glycemic variability in preterm infants during the first week of life.

Hypoglycemia in the preterm neonate: etiopathogenesis, diagnosis, management and long-term outcomes

Glucose, like oxygen, is of fundamental importance for any living being and it is the major energy source for the fetus and the neonate during gestation. The placenta ensures a steady supply of glucose to the fetus, while birth marks a sudden change in substrate delivery and a major change in metabolism. Hypoglycemia is one of the most common pathologies encountered in the neonatal intensive care unit and affects a wide range of neonates. Preterm, small for gestational age (GA) and intra-uterine growth restricted neonates are especially vulnerable due to their lack of metabolic reserves and associated co-morbidities. Nearly 30-60% of these high-risk infants are hypoglycemic and require immediate intervention. Preterm neonates are uniquely predisposed to developing hypoglycemia and its associated complications due to their limited glycogen and fat stores, inability to generate new glucose using gluconeogenesis pathways, have higher metabolic demands due to a relatively larger brain size, and are unable to mount a counter-regulatory response to hypoglycemia. In this review we will discuss the epidemiology; pathophysiology; clinical presentation; management and neurodevelopmental outcomes in affected infants and summarize evidence to develop a rational and scientific approach to this common problem.

Prediabetes in youth - mechanisms and biomarkers

Obesity has been estimated to decrease life expectancy by as little as 0.8 to as much as 7 years being the second leading cause of preventable death in the United States after smoking. Along with the increase in the prevalence of obesity, there has been a dramatic rise of the prevalence of prediabetes and type 2 diabetes among adolescents. Despite that, very little is known about the pathogenesis of these conditions in pediatrics and about how we could detect prediabetes in an early stage in order to prevent full blown diabetes. In this review we summarize the current knowledge on the pathophysiology of prediabetes and type 2 diabetes in adolescents and describe how biomarkers of beta-cell function might help identifying those individuals who are prone to progress from normal glucose tolerance towards prediabetes and overt type 2 diabetes. To better understand and fight this disease, we will need to explore and develop novel therapeutic strategies and individuate more sensitive and specific biomarkers that can allow an earlier detection of the disease.

Continuous determination of blood glucose in children admitted with malaria in a rural hospital in Mozambique

Background

Hypoglycaemia is a frequent complication among admitted children, particularly in malaria-endemic areas. This study aimed to estimate the occurrence of hypoglycaemia not only upon admission but throughout the first 72 h of hospitalization in children admitted with malaria.

Methods

A simple pilot study to continuously monitor glycaemia in children aged 0–10 years, admitted with malaria in a rural hospital was conducted in Southern Mozambique by inserting continuous glucose monitors (CGMs) in subcutaneous tissue of the abdominal area, producing glycaemia readings every 5 min.

Results

Glucose was continuously monitored during a mean of 48 h, in 74 children. Continuous measurements of blood glucose were available for 72/74 children (97.3%). Sixty-five of them were admitted with density-specific malaria diagnosis criteria (17 severe, 48 uncomplicated). Five children (7.7%) had hypoglycaemia (<54 mg/dL) on admission as detected by routine capillary determination. Analysing the data collected by the CGMs, hypoglycaemia episodes (<54 mg/dL) were detected in 10/65 (15.4%) of the children, of which 7 (10.8%) could be classified as severe (≤45 mg/dL). No risk factors were independently associated with the presence of at least one episode of hypoglycaemia (<54 mg/dL) during hospitalization. Only one death occurred among a normoglycaemic child. All episodes of hypoglycaemia detected by CGMs were subclinical episodes or not perceived by caregivers or clinical staff.

Conclusions

Hypoglycaemia beyond admission in children with malaria appears to be much more frequent than what had been previously described. The clinical relevance of these episodes of hypoglycaemia in the medium or long term remains to be determined.

Computer-determined dosage of insulin in the management of neonatal hyperglycaemia (HINT2): protocol of a randomised controlled trial

INTRODUCTION

Neonatal hyperglycaemia is frequently treated with insulin, which may increase the risk of hypoglycaemia. Computer-determined dosage of insulin (CDD) with the STAR-GRYPHON program uses a computer model to predict an effective dose of insulin to treat hyperglycaemia while minimising the risk of hypoglycaemia. However, CDD models can require more frequent blood glucose testing than common clinical protocols. The aim of this trial is to determine if CDD using STAR-GRYPHON reduces hypoglycaemia in hyperglycaemic preterm babies treated with insulin independent of the frequency of blood glucose testing.

METHODS AND ANALYSIS

Design: Multicentre, non-blinded, randomised controlled trial.

SETTING

Neonatal intensive care units in New Zealand and Australia.

PARTICIPANTS

138 preterm babies ≤30 weeks' gestation or ≤1500 g at birth who develop hyperglycaemia (two consecutive blood glucose concentrations ≥10 mmol/L, at least 4 hours apart) will be randomised to one of three groups: (1) CDD using the STAR-GRYPHON model-based decision support system: insulin dose and frequency of blood glucose testing advised by STAR-GRYPHON, with a maximum testing interval of 4 hours; (2) bedside titration: insulin dose determined by medical staff, maximum blood glucose testing interval of 4 hours; (3) standard care: insulin dose and frequency of blood glucose testing determined by medical staff. The target range for blood glucose concentrations is 5-8 mmol/L in all groups. A subset of babies will have masked continuous glucose monitoring.

PRIMARY OUTCOME

is the number of babies with one or more episodes of hypoglycaemia (blood glucose concentration <2.6 mmol/L), during treatment with insulin.

ETHICS AND DISSEMINATION

This protocol has been approved by New Zealand's Health and Disability Ethics Committee: 14/STH/26. A data safety monitoring committee has been appointed to oversee the trial. Findings will be disseminated to participants and carers, peer-reviewed journals, guideline developers and the public.

TRIAL REGISTRATION NUMBER

12614000492651.

Feasibility and acceptability of ambulatory glucose profile in children with Type 1 diabetes mellitus: A pilot study

BACKGROUND

Insulin administration and self-monitoring of blood glucose (SMBG) are pillars in the management of diabetes in children. Introduction of continuous glucose monitoring (CGM) has made it possible to understand the glycemic profiles which are not picked up by SMBG. Recent advent of flash glucose monitoring with inbuilt software to obtain ambulatory glucose profile (AGP) has emerged as a novel method to study glycemic patterns in adults with Type I diabetes. However, the use of AGP in children is yet to be explored.

METHODS

AGP was used in 46 children with Type 1 diabetes mellitus. Feasibility was measured regarding data and sensor failure. Acceptability was measured using a questionnaire.

RESULTS

Forty-six children (22 girls and 24 boys) with a mean age of 10.07 years and mean diabetes duration of 3.4 years were included in the study. In this cohort, for 30 (65.21%) subjects, the sensor remained in situ for a complete duration of 14 days. Except for minor discomfort, AGP was well accepted by most of the children and their parents.

CONCLUSION

AGP is a feasible option for monitoring glycemic status in children with diabetes with a high rate of acceptance.

Continuous glucose monitoring in preterm infants: evaluation by a modified Clarke error grid

Background

Continuous glucose monitoring using subcutaneous sensors has been validated in adults and children with diabetes, and was found to be useful in the management of glucose control. We aimed to assess feasibility and reliability of a new continuous glucose monitoring system (CGMS) in a population of preterm neonates using a Clarke error grid (CEG) specifically modified for preterm infants.

Methods

Preterm infants were recruited within 24 h from delivery. A subcutaneous sensor connected to a CGMS was inserted and maintained for 6 days. Data collected from CGMS were compared with data obtained using a glucometer. Management of the infants followed standard protocols and was not influenced by CGMS readings.

Results

Twenty patients (9 males) were included. Median (range) gestational age was 32 weeks (27–36) and median (range) birth weight was 1350 g (860–3360). Average CGMS recording time was 137 h, for a total of 449 paired glucose levels. CEG and modified CEG criteria for clinical significance were met.

Conclusion

CGMS is a safe and clinically adequate method to estimate glucose levels in preterm infants. As the glucose level can be evaluated in real time, this CGMS could be useful to reduce the number of heel sticks, to observe glycaemic trends and to promptly detect episodes of both hypo- and hyper-glycaemia.