Hypoglycemia: a complication of diabetes therapy in children

Fear of Hypoglycemia, Parenting Stress, and Metabolic Control for Children with Type 1 Diabetes and Their Parents

This study sets out to extend current knowledge of parenting stress and fear of hypoglycemia (FoH) in parents of children with type 1 diabetes mellitus (T1DM). We examined if the relationship between parental and children's FoH and metabolic control, as reflected by HbA1c, is mediated by parenting stress. A total of 63 parents and children with T1DM were recruited during their routine physician's appointment. Parents completed questionnaires on parenting stress and FoH. Children eight years and older also completed a questionnaire on FoH. HbA1c values were obtained from all children. Mediation analysis revealed an indirect association between parental FoH and HbA1c values through parenting stress (Sobel's z = 2.42, p = .02), but no indirect association between children's FoH and HbA1c. We concluded that parental FOH has an indirect association with the child's metabolic control that is mediated by parenting stress. More simply, fear of hypoglycemia predicts parent stress, which in turn, predicts metabolic control.

Continuous Subcutaneous Insulin Infusion in Children: A Pilot Study Validating a Protocol to Avoid Hypoglycemia at Initiation

BACKGROUND

The occurrence of hypoglycemia and hyperglycemia during the first days after transition to continuous subcutaneous insulin infusion (CSII) in patients with type 1 diabetes has not been systematically studied in children. The aim of this prospective study was to demonstrate that the protocol applied in our diabetes clinic is safe at CSII initiation in children.

METHODS

We assessed 22 pediatric patients with type 1 diabetes, using continuous glucose monitoring (CGM) before and after CSII initiation (±3 days).

RESULTS

After CSII initiation, there was no difference in the rates of hypoglycemic events expressed as relative rates (RRs) per person-reading (RR = 0.85, p = 0.52, 95% CI 0.52-1.39), as well as in the number of prolonged hypoglycemic events (>1 h) per day (RR = 1.12, p = 0.56, 95% CI 0.75-1.68). We observed only a trend toward prolonged episodes of hyperglycemia after pump initiation (RR = 1.52, p = 0.06, 95% CI 0.97-2.35).

CONCLUSION

Our study is the first to assess, through CGM and in a prospective way, the impact of a CSII initiation protocol on glycemic values. Our protocol provides a safe model to avoid hypoglycemia at CSII initiation in children.

CLINICAL TRIAL REGISTRATION

www.ClinicalTrials.gov, identifier NCT01840358.

Non-invasive hypoglycemia monitoring system using extreme learning machine for Type 1 diabetes

Hypoglycemia is a very common in type 1 diabetic persons and can occur at any age. It is always threatening to the well-being of patients with Type 1 diabetes mellitus (T1DM) since hypoglycemia leads to seizures or loss of consciousness and the possible development of permanent brain dysfunction under certain circumstances. Because of that, an accurate continuing hypoglycemia monitoring system is a very important medical device for diabetic patients. In this paper, we proposed a non-invasive hypoglycemia monitoring system using the physiological parameters of electrocardiography (ECG) signal. To enhance the detection accuracy, extreme learning machine (ELM) is developed to recognize the presence of hypoglycemia. A clinical study of 16 children with T1DM is given to illustrate the good performance of ELM.

Association of obesity with chronic disease and musculoskeletal factors

SummaryIntroduction:overweight and obesity in adolescents are major public health problems with particular interest, because of their potential association with risk factors for development of diseases. The study aimed to determine the prevalence of overweight and obesity in adolescents in southern Portugal and investigate the association with risk factors for development of cardiovascular, respiratory and musculoskeletal diseases.Methods:the sample consisted of 966 adolescents aged 10 to 16 years. The calculation of body mass index (BMI), evaluation of blood glucose, total cholesterol and triglycerides, blood pressure, spirometry and application of low back pain (LBP) questionnaire were performed.Results:178 (18.4%) adolescents were overweight and 52 (5.4%) obese. None of the variables revealed a statistically significant association with overweight and obesity. The presence of high blood pressure was observed in 200 (20.7%) individuals and hypertension in 158 (16.4%) adolescents. Overweight and obese adolescents are 2.3 times more likely to develop signs of pre-hypertension and hypertension. 559 (57.9%) students had restrictive respiratory disorders and 23 (2.4%) had obstructive disorders. Those who were overweight and obese had 0.64 probability of having restrictive respiratory disorders.Conclusion:there was a high prevalence of overweight and obesity in Portuguese adolescents and these showed a statistically significant relationship with the development of pre-hypertension and hypertension, and restrictive respiratory disorders.

Evaluation of Pre-Treatment and Post-Treatment S100B, Oxidant and Antioxidant Capacity in Children with Diabetic Ketoacidosis

OBJECTIVE

The study aimed to evaluate the pre-treatment and post-treatment oxidant capacity, antioxidant capacity and S100B protein levels in cases of diabetic ketoacidosis (DKA).

METHODS

The study included 49 pediatric patients diagnosed with DKA and a control group comprising 49 healthy children. Blood samples were obtained after confirmation of the DKA diagnosis and also after treatment. S100B, total oxidant (TOL) and total antioxidant levels (TAL) were measured and the oxidative stress index (OSI) was calculated.

RESULTS

When the pre-treatment and post-treatment values of patients with DKA were compared with those of the healthy control group, the S100B level, TOL, TAL and OSI were found to be significantly higher in the diabetes group (p<0.001). Pre-treatment TOL and TAL were also significantly higher than post-treatment levels (p<0.001), while no statistically significant difference was found in the S100B levels or the OSI (p>0.05).

CONCLUSION

We believe that long-term exposure to high blood glucose concentrations leads to an increase in TOL in patients with DKA and that the neurotransmitter changes that develop in response to this exposure lead to an increase in S100B levels, which is an indicator of neuronal damage.

Severe hypoglycemia in a juvenile diabetic rat model: presence and severity of seizures are associated with mortality

It is well accepted that insulin-induced hypoglycemia can result in seizures. However, the effects of the seizures, as well as possible treatment strategies, have yet to be elucidated, particularly in juvenile or insulin-dependent diabetes mellitus (IDDM). Here we establish a model of diabetes in young rats, to examine the consequences of severe hypoglycemia in this age group; particularly seizures and mortality. Diabetes was induced in post-weaned 22-day-old Sprague-Dawley rats by streptozotocin (STZ) administered intraperitoneally (IP). Insulin IP (15 U/kg), in rats fasted (14-16 hours), induced hypoglycemia, defined as <3.5 mM blood glucose (BG), in 68% of diabetic (STZ) and 86% of control rats (CON). Seizures occurred in 86% of STZ and all CON rats that reached hypoglycemic levels with mortality only occurring post-seizure. The fasting BG levels were significantly higher in STZ (12.4 ± 1.3 mM) than in CON rodents (6.3 ± 0.3 mM), resulting in earlier onset of hypoglycemia and seizures in the CON group. However, the BG at seizure onset was statistically similar between STZ (1.8 ± 0.2 mM) and CON animals (1.6 ± 0.1 mM) as well as between those that survived (S+S) and those that died (S+M) post-seizure. Despite this, the S+M group underwent a significantly greater number of seizure events than the S+S group. 25% glucose administered at seizure onset and repeated with recurrent seizures was not sufficient to mitigate these continued convulsions. Combining glucose with diazepam and phenytoin significantly decreased post-treatment seizures, but not mortality. Intracranial electroencephalograms (EEGs) were recorded in 10 CON and 9 STZ animals. Predictive EEG changes were not observed in these animals that underwent seizures. Fluorojade staining revealed damaged cells in non-seizing STZ animals and in STZ and CON animals post-seizure. In summary, this model of hypoglycemia and seizures in juvenile diabetic rats provides a paradigm for further study of underlying mechanisms. Our data demonstrate that severe hypoglycemia (<2.0 mM) is a necessary precondition for seizures, and the increased frequency of these seizures is associated with mortality.

Neuronal damage and cognitive impairment associated with hypoglycemia: An integrated view

The aim of the present review is to offer a current perspective about the consequences of hypoglycemia and its impact on the diabetic disorder due to the increasing incidence of diabetes around the world. The main consequence of insulin treatment in type 1 diabetic patients is the occurrence of repetitive periods of hypoglycemia and even episodes of severe hypoglycemia leading to coma. In the latter, selective neuronal death is observed in brain vulnerable regions both in humans and animal models, such as the cortex and the hippocampus. Cognitive damage subsequent to hypoglycemic coma has been associated with neuronal death in the hippocampus. The mechanisms implicated in selective damage are not completely understood but many factors have been identified including excitotoxicity, oxidative stress, zinc release, PARP-1 activation and mitochondrial dysfunction. Importantly, the diabetic condition aggravates neuronal damage and cognitive failure induced by hypoglycemia. In the absence of coma prolonged and severe hypoglycemia leads to increased oxidative stress and discrete neuronal death mainly in the cerebral cortex. The mechanisms responsible for cell damage in this condition are still unknown. Recurrent moderate hypoglycemia is far more common in diabetic patients than severe hypoglycemia and currently important efforts are being done in order to elucidate the relationship between cognitive deficits and recurrent hypoglycemia in diabetics. Human studies suggest impaired performance mainly in memory and attention tasks in healthy and diabetic individuals under the hypoglycemic condition. Only scarce neuronal death has been observed under moderate repetitive hypoglycemia but studies suggest that impaired hippocampal synaptic function might be one of the causes of cognitive failure. Recent studies have also implicated altered mitochondrial function and mitochondrial oxidative stress.

NON-INVASIVE NOCTURNAL HYPOGLYCEMIA DETECTION FOR INSULIN-DEPENDENT DIABETES MELLITUS USING GENETIC FUZZY LOGIC METHOD

Hypoglycemia, or low blood glucose, is the most common complication experienced by Type 1 diabetes mellitus (T1DM) patients. It is dangerous and can result in unconsciousness, seizures and even death. The most common physiological parameter to be effected from hypoglycemic reaction are heart rate (HR) and correct QT interval (QTc) of the electrocardiogram (ECG) signal. Based on physiological parameters, a genetic algorithm based fuzzy reasoning model is developed to recognize the presence of hypoglycemia. To optimize the parameters of the fuzzy model in the membership functions and fuzzy rules, a genetic algorithm is used. A validation strategy based adjustable fitness is introduced in order to prevent the phenomenon of overtraining (overfitting). For this study, 15 children with 569 sampling data points with Type 1 diabetes volunteered for an overnight study. The effectiveness of the proposed algorithm is found to be satisfactory by giving better sensitivity and specificity compared with other existing methods for hypoglycemia detection.

Acute hypoglycemia causes depressive-like behaviors in mice

Reports in humans advocate a link between hypoglycemia and altered mood. Such observations, however, have not been mechanistically explored. Here we examined depressive-like behaviors in mice resulting from acute hypoglycemia. Mice were fasted for 12 hours and then administered intraperitoneal insulin to induce a blood glucose nadir of 50 mg/dL at 0.75 hour after injection that by 2 hours postinjection had returned to normal. The behaviors of locomotion, forced swim, saccharin preference, and novel object recognition were subsequently examined. Mice made hypoglycemic showed depressive-like behaviors 24 hours after resolution of hypoglycemia as evidenced by increased immobility in the forced swim test (FST) and reduced saccharin preference. Movement and memory were not impacted by hypoglycemia 24 hours after its resolution. By 48 hours posthypoglycemia, depressive-like behaviors resolved. In contrast, neither peripheral insulin administration without resultant hypoglycemia nor intracerebroventricular insulin administration altered performance in the FST. The antidepressants fluoxetine and desipramine prevented hypoglycemia-induced immobility in the FST, as did the antiadrenergic agents phentolamine, metoprolol, and butoxamine. Epinephrine and norepinephrine administration caused increased immobility in the FST at 24 hours postadministration that subsequently resolved by 48 hours. These data indicate that, in mice, acute hypoglycemia through adrenergic pathways caused depressive-like behaviors that exist well beyond the resolution of hypoglycemia.

Moderate recurrent hypoglycemia during early development leads to persistent changes in affective behavior in the rat

Recurrent hypoglycemia is a common problem among infants and children that is associated with several metabolic disorders and insulin-dependent diabetes mellitus. Although studies have reported a relationship between a history of juvenile hypoglycemia and psychological health problems, the direct effects of recurrent moderate hypoglycemia have not been fully determined. Thus, in this study, we used an animal model to examine the effects of recurrent hypoglycemia during the juvenile period on affective, social, and motor function (assessed under euglycemic conditions) across development. To model recurrent hypoglycemia, rats were administered 5 U/kg of insulin or saline twice per day from postnatal day (P)10 to P19. Body weight gain was retarded in insulin-treated rats during the treatment period, but recovered by the end of treatment. However, insulin-treated rats displayed increases in affective reactivity that emerged early during treatment and persisted after treatment into early adulthood. Specifically, insulin-treated pups showed increased maternal separation-induced vocalizations as infants, and an exaggerated acoustic startle reflex as juveniles and young adults. Moreover, young adult rats with a history of recurrent juvenile hypoglycemia exhibited increased fear-potentiated startle and increases in behavioral and hormonal responses to restraint stress. Some of these effects were sex-dependent. The changes in affective behavior in insulin-exposed pups were accompanied by decreases in adolescent social play behavior. These results provide evidence that recurrent, transient hypoglycemia during juvenile development can lead to increases in fear-related behavior and stress reactivity. Importantly, these phenotypes are not reversed with normalization of blood glucose and may persist into adulthood.

Selective vulnerability of brain regions to oxidative stress in a non-coma model of insulin-induced hypoglycemia

Insulin-induced hypoglycemia causes the death of neurons in particular brain regions including the cerebral cortex, the striatum and the hippocampus, while the cerebellum and the brain stem are more resistant. The mechanisms underlying this selective vulnerability to hypoglycemic damage are unknown. In the present study we have analyzed the presence of lipoperoxidation products and nitrosilated protein residues in different rat brain regions during and after the induction of hypoglycemia. Insulin-injected hypoglycemic rats were sacrificed before the onset of the isoelectric period or infused with glucose to end hypoglycemia, and then sacrificed at different times. Increased lipoperoxidation levels were observed before the onset of the isoelectric period, while 3-nitrotyrosine (NT) residues in proteins and NT-positive cells were only observed after glucose reperfusion. These changes were found only in vulnerable brain regions, while none of them was evident in the cerebellum, suggesting a correlation between oxidative damage and vulnerability to hypoglycemic neuronal death in selective brain regions. Results suggest that a pro-oxidant state is promoted in certain brain regions during hypoglycemia and after the glucose reperfusion phase, which might result from the activation of several oxidative stress pathways and may be related to subsequent cell death.

Use of continuous insulin infusion pumps in young children with type 1 diabetes: a systematic review

INTRODUCTION

Although insulin pump therapy has been successful in adults and adolescents, its use has been limited in young children because of perceived risk of severe or frequent hypoglycemia. The purpose of this review is to evaluate the safety and efficacy of continuous subcutaneous insulin infusion (CSII) in young children with type 1 diabetes.

METHODS

We searched Medline, PubMed, and CINAHL for clinical trials comparing multiple-dose injection therapy to CSII therapy in children 6 years of age or younger who were diagnosed with type 1 diabetes at least 6 months prior to study. Primary outcome measures were glycosylated hemoglobin (HbA1c) and hypoglycemic episodes. Other outcomes of interest were quality of life and parental satisfaction.

RESULTS

Most studies showed significant improvements in HbA1c and trends of decreased hypoglycemia. Quality of life improved in most CSII groups. Parental satisfaction with therapy was evidenced by continuation of CSII after study completion.

DISCUSSION

Current evidence indicates CSII is a safe and effective method of insulin delivery in young children. When parents are highly motivated, CSII should be offered as a mode of insulin delivery for this age group.

[Insulin therapy for type 1 diabetes mellitus: past and present]

The discovery of insulin can be considered the milestone of diabetes mellitus history and a great achievement for its treatment. The first insulin available was the regular. Afterwards, Hagedorn added the protamine to the insulin, thus, creating the NPH insulin. In the 1950s an insulin free of protamine was synthesized: the lente insulin. With the advent of molecular biology, synthetic human insulin was synthesized using recombinant DNA technology. Most recently several types of insulin analogues were available, providing the patients with better metabolic control. Type 1 diabetes mellitus treatment includes plain substitution and individualization for short-acting plus long-acting insulin according to the physician's assistance, besides regular practice of physical activities and diet orientations. In type 1 diabetes mellitus the insulin of low variability is the best choice since basal/bolus insulin therapy or continuous subcutaneous insulin infusion pump can mimetize the physiological release of insulin by beta cells.

Cognitive dysfunction and diabetes: implications for primary care

It is increasingly recognized that diabetes mellitus can lead to long-term complications in the brain. Clinically, these complications are manifested in alterations in cognitive functioning. This paper offers an overview on the impact of diabetes on cognition and provides leads for the evaluation and management of cognitive disturbances in patients with diabetes in a primary care setting. The main message is that while some patient groups appear to be at increased risk of cognitive impairments, in the majority of patients diabetes is not associated with the development cognitive decrements that would be regarded as clinically relevant. Frank impairments of cognition mainly occur in patients above the age of 65, often in association with vascular co-morbidity. Other groups at risk for cognitive decrements are children with an early age at diabetes onset and patients with clinically manifest retinopathy or other microvascular complications. No specific treatment options are available, but for now treatment of vascular risk factors and attention for glycaemic control appears to be a logical approach. Given the recent progress in this field, new treatments to prevent cognitive impairment in patients with diabetes may hopefully become available in the near future.

Feasibility and safety of insulin pump therapy in children aged 2 to 7 years with type 1 diabetes: a retrospective study

BACKGROUND AND OBJECTIVES

Although insulin pump therapy has been successful in adults, adolescents and school children, its use has been limited in young children. The purpose of this study was to evaluate the glycemic control, safety and efficacy of continuous subcutaneous insulin infusion via pump in young children (2-7 years old) with type 1 diabetes who were transitioned from twice-a-day insulin injection (neutral protamine Hagedorn/Lente + Humalog/Novalog) to insulin pump therapy. Hemoglobin A1c, BMI, average fasting blood glucose, episodes of severe hypoglycemia, episodes of diabetic ketoacidosis, episodes of lipohypertrophy, blood glucose variability, and number of sick day calls were compared before and after insulin pump therapy.

METHODS

Data were collected retrospectively by chart review over a 2-year period during quarterly diabetes clinic visits from 33 patients who were managed on neutral protamine Hagedorn/Lente + Humalog/Novolog twice-a-day injections for at least 1 year prior to transitioning to insulin pump therapy.

RESULTS

There was a significant improvement in the average hemoglobin A1c after continuous subcutaneous insulin infusion therapy. The average fasting blood sugar was lower in the continuous subcutaneous insulin infusion group. Severe episodes of hypoglycemia and episodes of lipohypertrophy were significantly higher before insulin pump therapy initiation. There were significantly fewer sick day calls after continuous subcutaneous insulin infusion. Blood sugar variability improved significantly after insulin pump therapy. There was no significant difference in BMI or amount of carbohydrate consumed. None of the patients experienced diabetic ketoacidosis requiring emergency treatment before or after insulin pump therapy.

CONCLUSIONS

Continous subcutaneous insulin infusion therapy in young children with type 1 diabetes is a safe, effective and superior alternative to a twice-a-day insulin regimen.

Use of insulin glargine in children under age 6 with type 1 diabetes

AIM

Children under 6 yr have the highest incidence of severe hypoglycemia (SH) and the greatest likelihood of brain damage from SH. The purpose of this study is to evaluate the use of insulin glargine (Lantus in children under age 6 with type 1 diabetes (T1D).

METHODS

The electronic medical records were reviewed for patients under age 6 during the first 6 months of insulin glargine therapy and compared with age, sex, and duration of diabetes for matched control patients on neutral protamine Hagedorn (NPH) insulin. Data from 128 subjects (32 male pairs and 32 female pairs) were collected relating to the incidence of severe and non-severe hypoglycemic events, hemoglobin A1c (HbA1c) values, body mass index (BMI), and daily insulin dose. Additionally, parents were asked to complete a diabetes Quality of Life (QoL) survey.

RESULTS

In the 6 months before the study period, the glargine group had 16 SH events compared with three in the 6 months post-glargine. The comparison (NPH) group had seven and six SH events in their respective 6-month periods. Nighttime SH events in the glargine group decreased from 12 prestudy events to one during the study period. The average daily insulin dose in the glargine group was higher than that in the NPH group (0.8+/- 0.2 vs. 0.7+/- 0.2 U/kg/day; p=0.03). The HbA1c values, BMI, and QoL responses were not significantly different between the two groups.

CONCLUSIONS

SH was decreased, particularly at night (from 12 episodes to one), after the introduction of glargine in young children with T1D.

Severe hypoglycaemia, metabolic control and diabetes management in children with type 1 diabetes in the decade after the Diabetes Control and Complications Trial -- a large-scale multicentre study

Hypoglycaemia is frequently the limiting factor in achieving optimal glycaemic control. Therefore, insulin therapy, the incidence of hypoglycaemia, and glycaemic control were investigated in 6309 unselected children with type 1 diabetes in a large-scale multicentre study. Using standardised computer-based documentation, the incidence of severe hypoglycaemia, HbA1( c) levels, insulin regimen, diabetes duration, and the number of patients attending a treatment centre were investigated for the age groups 0-<5 years ( n =782), 5-<7 years ( n =1053), and 7-<9 years ( n =4474). The average HbA1( c) level was 7.6% (no significant difference between age groups). Young children had more severe hypoglycaemic events (31.2/100 patient years) as compared to older children (19.7; 21.7/100 patient years, P <0.05) independent of the treatment regimen. Our data suggest that diabetes centres treating less than 50 patients per year have a higher incidence of hypoglycaemia in 0-<5-year-old children (43.0/100 patient years) as compared to larger centres (24.1/100 patient years; P <0.0001). Significant predictors of hypoglycaemia were younger age ( P <0.0001), longer diabetes duration ( P <0.0001), higher insulin dose/kg per day ( P <0.0001), injection regimen ( P <0.0005), and centre experience ( P <0.05).

CONCLUSION

Despite modern treatment, young children have an elevated risk for developing severe hypoglycaemia compared to older children, especially when treated at smaller diabetes centres. The therapeutic goal of carefully regulating metabolic control without developing hypoglycaemia has still not been achieved. Further advances in diabetic treatment may result from giving more attention to hypoglycaemia in young children.

Insulin therapy and hypoglycaemia: the size of the problem

BACKGROUND AND METHODS

Hypoglycaemia is a fact of life for people with diabetes mellitus. Mild, asymptomatic episodes occur once or twice a week in insulin-treated diabetic subjects. Asymptomatic hypoglycaemia, including nocturnal hypoglycaemia, occurs in about 25% of diabetic subjects treated with insulin therapy. Mild hypoglycaemia, if recurrent, induces unawareness of hypoglycaemia and impairs glucose counterregulation, which in turn predisposes to severe hypoglycaemia. Even brief hypoglycaemia can cause profound dysfunction of the brain. Prolonged, severe hypoglycaemia can cause permanent neurological sequels. In addition, it is possible that hypoglycaemia may accelerate the vascular complications of diabetes by increasing platelet aggregation and/or fibrinogen formation. Finally, hypoglycaemia may be fatal. Hypoglycaemia induced by insulin as treatment of type 1 diabetes mellitus (T1 DM) is not the consequence of diabetes, but invariably of the non-physiological replacement of insulin.

RESULTS

A number of studies have demonstrated that by moving from non-physiological to more physiological models of insulin therapy, most of the hypoglycaemia problems may be overcome, the percentage of glycated hemoglobin (A1c) decreased, and the quality of life improved. Interestingly, in T1 DM with hypoglycaemia unawareness, prevention of hypoglycaemia reverses not only unawareness but also improves glucose counterregulation, primarily the responses of adrenaline.

CONCLUSIONS

In order to best prevent hypoglycaemia, insulin should preferably be given as continuous subcutaneous infusion via a minipump (the 'golden standard') or multiple daily insulin administrations with insulin analogues (basal insulin glargine, meal insulin rapid-acting insulin analogues) in T1 DM.

The impact of a decade of changing treatment on rates of severe hypoglycemia in a population-based cohort of children with type 1 diabetes

OBJECTIVE

To determine the impact of changes to treatment on the incidence of severe hypoglycemia and its risk factors in a large population-based cohort of children with type 1 diabetes.

RESEARCH DESIGN AND METHODS

The cohort consisted of 1,335 children (age at entry 9.5 +/- 4.3 years [mean +/- SD], range 0-18), yielding 6,928 patient-years of data. The mean follow-up period was 4.7 +/- 3.1 years (range 0-10.7). Prospective assessment of severe hypoglycemia (an event leading to loss of consciousness or seizure) and associated clinical factors and outcomes was made between 1992 and 2002. Patients were reviewed every 3 months. Data were analyzed using the negative binomial regression model.

RESULTS

A total of 944 severe events were recorded. The incidence of severe hypoglycemia increased significantly by 29% per year for the first 5 years but appeared to plateau over the last 5 years. The overall average HbA1c significantly decreased (by 0.2% per year) over the whole follow-up period. An increased risk of severe hypoglycemia was associated with lower HbA1c, younger age, higher insulin dose, male sex, and lower parental socioeconomic status. Of insulin therapies, only pump treatment was associated with reduced rates of severe hypoglycemia.

CONCLUSIONS

Severe hypoglycemia remains a major problem for children and adolescents with type 1 diabetes. Recent approaches to therapy may be allowing a degree of improved control without the expected increased risk of severe hypoglycemia but further monitoring will be important.

Hypoglycemia in children with type 1 diabetes: current issues and controversies

Hypoglycemia is a common complication of insulin therapy, particularly in the young. For children and adolescents with diabetes, the risk of hypoglycemia may not only prevent optimal glycemic control but can also add significantly to the psychosocial burden of the disease. Recently, surveys employing prospective monitoring techniques have allowed more precise information to be gained about rates of hypoglycemia, its clinical associations, and the impact of new therapies and technologies. A number of reports have estimated rates of hypoglycemic comas and convulsions to be approximately 20 events per 100 patient years in children on current conventional therapy. There is evidence that the introduction of new analog short- and longer-acting insulins and the more widespread use of continuous subcutaneous infusion therapies may allow improvements in glycemic control to occur without the usual increased rate of severe hypoglycemic episodes. The use of glucose sensor technology has brought into focus the widespread occurrence of asymptomatic hypoglycemia. Asymptomatic hypoglycemia has long been recognized, particularly at night, when the combination of excessive insulin action and suppressed counter-regulatory hormone responses put children at special risk of hypoglycemia. Hypoglycemia unawareness is common in the young and is associated with an increased risk of severe hypoglycemia. Whether episodes of severe hypoglycemia have long-term consequences is controversial. Early studies suggesting that the developing brain is sensitive to permanent neurological damage as a result of hypoglycemia have not been confirmed in more recent reports. Many studies have not found convincing evidence of neurological sequelae of the hypoglycemic events that are an inevitable complication of insulin therapy. The question, however, remains under active investigation. Continued prospective monitoring of hypoglycemia rates and consequences has become an essential component of diabetes management.

Comparison of continuous subcutaneous insulin infusion and multiple daily injection regimens in children with type 1 diabetes: a randomized open crossover trial

OBJECTIVE

To compare the efficacy and feasibility of continuous subcutaneous insulin infusion (CSII) with multiple daily insulin injections (MDI) in children with type 1 diabetes.

METHODS

The study sample included 23 children (10 males) aged 9.4 to 13.9 years with type 1 diabetes. An open randomized crossover design was used to compare 3.5 months of CSII to 3.5 months of MDI therapy for the following variables: diabetic control, incidence of adverse events, daily insulin requirement, body mass index standard deviation scores, treatment satisfaction, and quality of life.

RESULTS

The changes in HbA(1c) and fructoseamine values were similar in the 2 arms over time. At the end of the study, mean HbA(1c) level measured 8.05 +/- 0.78%. There were no differences between the treatment modes in frequency of symptomatic hypoglycemic or hyperglycemic events. There was 1 event of severe hypoglycemia during pump therapy and 3 during MDI, yielding a rate of 0.26 events per patient-year. There were no episodes of diabetic ketoacidosis. Body mass index standard deviation scores decreased during CSII and increased during MDI, as did mean insulin dose. Patients expressed a higher treatment satisfaction from CSII than MDI, although there was no difference in quality of life between the 2 modes.

CONCLUSIONS

Intensive insulin therapy by either insulin pump or MDI is safe in children and young adolescents with type 1 diabetes, with similar diabetes control and a very low rate of adverse events. We suggest that both modes be available to the diabetic team to better tailor therapy.

Characteristics of glycemic control in young children with type 1 diabetes

BACKGROUND

The Diabetes Control and Complications Trial (DCCT) demonstrated that the rate-limiting step to the intensification of diabetes management in adolescents and adults was hypoglycemia. Young children were presumed to be at even greater risk for hypoglycemia with severe consequences, particularly if they had HbA1c levels < 8%.

SUBJECTS

A retrospective chart review was performed on 148 patients with type 1 diabetes on insulin injection therapy who were < 8 yr of age (mean age 5.7 +/- 1.5, mean diabetes duration 3.0 +/- 1.4 yr) followed quarterly from July 1999 to June 2001.

METHODS

The subjects were divided into two groups based on their mean HbA1c values (< 8 vs. > or = 8%) averaged over the 2-yr time period. The following variables were analyzed comparing the two groups: age, duration of diabetes, insulin dose, severe hypoglycemic episodes, episodes of diabetic ketoacidosis (DKA), percentage of glucose levels above, within, and below the target range, and number of diabetes home-management competencies obtained.

RESULTS

Patients with HbA1c < 8% spent more time within target range (40.0 vs. 29.5%, p = 0.0001) and less time above their target range (36.9 vs. 51.2%, p = 0.0003). There was no difference in the percentage of glucose levels below target (23.2 vs. 19.4%, p = NS), percentage of severe hypoglycemic episodes (3 vs. 7 episodes per 100 patient-yr, p = NS), or episodes of DKA (1 vs. 3 episodes per 100 patient-yr, p = NS) between the two groups. SUBJECTS with lower HbA1c levels had acquired more home-management competencies (4.0 vs. 3.5, p = 0.01).

CONCLUSIONS

If families are competent in fundamental diabetes management, young children can achieve HbA1c levels < 8.0% without increasing the risk of hypoglycemia.

Insulin pump therapy in toddlers and preschool children with type 1 diabetes mellitus

OBJECTIVE

To test whether glycemic control in young children could be achieved more effectively and safely by using continuous insulin infusions administered by insulin pumps.

STUDY DESIGN

We analyzed the effects of pump therapy in nine toddlers in whom type 1 diabetes developed between the ages of 10 and 40 months. After a mean of 13.7 months of therapy with multiple daily injections, patients were treated with insulin pumps for periods ranging from 7 to 19 months (mean, 12.7 months).

RESULTS

Before initiation of pump therapy, HbA1c levels averaged 9.5% +/- 0.4%, and patients had a mean of 0.52 episodes per month of severe hypoglycemia (uncontrolled shaking, inconsolable crying, disorientation, or seizures). After initiation of pump therapy, HbA1c levels declined to 7.9% +/- 0.3% (P <.001 vs prepump levels), and the incidence of severe hypoglycemia decreased to 0.09 episodes per month (P <.05). Normal linear growth and weight gain were maintained during pump therapy. There were no changes in the frequency of physician or emergency room visits for acute hyperglycemia or ketoacidosis. However, the frequency of parental contacts with health personnel declined by >80%, reflecting increasing parental confidence and independence in diabetic care. Subjective assessments revealed significant improvements in quality of life and high levels of satisfaction with pump therapy.

CONCLUSIONS

Insulin pump therapy may provide an effective alternative for selected preschool children with type 1 diabetes.